Dual frame prosthesis with atrialized inner frame

Abstract

Transcatheter heart valve prostheses including a dual frame stent structure are disclosed herein. The dual frame stent structure includes an inner frame and an outer frame, and an outflow end of the inner frame is attached to an outflow end of the outer frame. The inflow end of the transcatheter heart valve prosthesis is disposed within and floats freely within a patient's atrium and the outflow end of the transcatheter heart valve prosthesis does not extend or only minimally extends into the patient's left ventricle of the heart to avoid obstruction of the left ventricular outflow tract (LVOT).

Description

DUAL FRAME PROSTHESIS WITH ATRIALIZED INNER FRAMECross-Reference to Related Applications

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 671832, filed July 16, 2024; U.S. Provisional Patent Application Serial No. 63 / 671829, filed July 16, 2024; U.S. Provisional Patent Application Serial No. 63 / 671828, filed July 16, 2024; and U.S. Provisional Patent Application Serial No. 63 / 514158, filed July 18, 2023, each of which is hereby incorporated by reference in its entirety for all purposes.Field of the Invention

[0002] The present disclosure relates generally to prosthetic valves, and more particularly to embodiments of a dual frame stent structure for a transcatheter heart valve prosthesis.Background

[0003] Diseases associated with heart valves, such as those caused by damage or a defect, can include stenosis and valvular insufficiency or regurgitation. For example, valvular stenosis causes the valve to become narrowed and hardened which can prevent blood flow to a downstream heart chamber from occurring at the proper flow rate and may cause the heart to work harder to pump the blood through the diseased valve. Valvular insufficiency or regurgitation occurs when the valve does not close completely, allowing blood to flow backwards, thereby causing the heart to be less efficient. A diseased or damaged valve, which can be congenital, age-related, drug- induced, or in some instances, caused by infection, can result in an enlarged, thickened heart that loses elasticity and efficiency. Some symptoms of heart valve diseases can include weakness, shortness of breath, dizziness, fainting, palpitations, anemia and edema, and blood clots which can increase the likelihood of stroke or pulmonary embolism. Symptoms can often be severe enough to be debilitating and / or life threatening.

[0004] Transcatheter heart valve prostheses have been developed for repair and replacement of diseased and / or damaged heart valves. Such transcatheter heart valve prostheses can be percutaneously delivered and deployed at the site of the diseased heart valve through catheter-based delivery systems. Such transcatheter heart valve prostheses can be delivered while in a radially compressed configuration so that the valve prosthesis can be advanced through the patient’s vasculature. Once positioned at the treatment site, the transcatheter valve prosthesis canbe expanded to engage tissue at the diseased heart valve region to, for instance, hold the transcatheter heart valve prosthesis in position.

[0005] While these transcatheter heart valve prostheses offer minimally invasive methods for heart valve repair and / or replacement, challenges remain. In particular, when implanted at a native mitral valve prosthesis, left ventricular outflow tract obstruction (LVOTO) is a concern. LVOTO may result in patient eligibility issues and / or risk to the patient for obstruction or restricted blood flow into the aortic valve. Similarly, native tricuspid valves have a relatively short distance between the native tricuspid valve and the wall of the right ventricle. Native mitral valves and native tricuspid valves may also be referred to generally as atrioventricular valves, as they regulate flow between an atrium of the heart and a ventricle of the heart. Thus, for at least the reasons noted above, it is desirable to minimize the distance a transcatheter heart valve prosthesis protrudes into a ventricle of a native atrioventricular valve.

[0006] Additionally, transcatheter heart valve prostheses may migrate and / or tilt following implantation at the treatment site. Transcatheter heart valve prostheses typically employ antimigration mechanisms such as cleats or other protruding elements which extend radially to contact the native heart tissue in order to resist migration following placement in the diseased tissue. Designs of dual frame prostheses must therefore balance efforts to reduce LVOTO while improving migration resistance. Thus, for at least the reasons noted above, it is desirable to develop transcatheter heart valve prosthesis designs which improve migration resistance without negatively affecting LVOTO.Summary

[0007] A transcatheter heart valve prosthesis according to an embodiment hereof includes an inner frame, an outer frame, and a prosthetic valve component. The inner frame includes a cylindrical portion and a flared portion extending distally and radially outward from the cylindrical portion. The cylindrical portion defines an inflow end of the inner frame having a first outer diameter and the flared portion defines an outflow end of the inner frame having a second outer diameter that is greater than the first outer diameter. The cylindrical portion is oriented to extend generally parallel to a longitudinal axis of the transcatheter heart valve prosthesis. The outer frame circumferentially surrounds at least a portion of the inner frame. The outer frame includes a fixation region having a third outer diameter that is constant from a first end of the fixation region to a second end of the fixation region which defines an outflow end of the outer frame. The firstend of the fixation region is radially spaced from the inner frame and the second end of the fixation region is attached to the outflow end of the inner frame. The prosthetic valve component is disposed within and attached to the cylindrical portion of the inner frame.

[0008] In an embodiment, the fixation region has a first height from the first end to the second end thereof and the inner frame has a second height from the inflow end to the outflow end thereof. The second height may be between 0 and 250 % longer than the first height.

[0009] In an embodiment, the fixation region is configured to engage heart tissue at or below a native annulus of a native mitral heart valve.

[0010] In an embodiment, the fixation region is oriented to extend generally parallel to the longitudinal axis of the transcatheter heart valve prosthesis.

[0011] In an embodiment, the inner frame includes a plurality of endmost outflow crowns, the outer frame includes a plurality of endmost outflow crowns, and a ratio of the endmost outflow crowns of the outer frame to the endmost outflow crowns of the inner frame is 2: 1.

[0012] In an embodiment, the flared portion of the inner frame is flared outwardly from a first end to a second end thereof, with the first end of the flared portion having the first outer diameter and the second end of the flared portion, which defines the outflow end of the inner frame, having the second outer diameter.

[0013] In an embodiment, the inner frame includes three rows of openings including a first row of openings within the cylindrical portion, a second row of openings within the cylindrical portion and the flared portion, and a third row of openings within the flared portion.

[0014] In an embodiment, the inner frame includes exactly three rows of openings including a first row of openings within the cylindrical portion, a second row of openings within the cylindrical portion and the flared portion, and a third row of openings within the flared portion.

[0015] In an embodiment, the outflow end of the inner frame includes an outflow ring of struts and crowns, and the outflow ring is oriented to extend generally parallel to the longitudinal axis of the transcatheter heart valve prosthesis.

[0016] In an embodiment, the openings of the first and second rows are formed via a plurality of struts and a plurality of crowns, and the third row of openings is formed via the outflow ring, endmost struts of the second row of openings, and a plurality of radially-extending segments extending between endmost crowns of the second row of openings and endmost crowns of the outflow ring.

[0017] In an embodiment, each opening of the third row of openings is formed by exactly two adjacent struts of the outflow ring, two adjacent endmost struts of the second row of openings, and two adjacent radially extending segments.

[0018] In an embodiment, each opening of the third row of openings is formed by exactly four adjacent struts of an outflow ring, two adjacent endmost struts of the second row of openings, and two adjacent radially extending segments.

[0019] In an embodiment, the openings of the first, second, and third rows are formed via a plurality of struts and a plurality of crowns.

[0020] In an embodiment, openings of the first and second rows have a first shape and openings of the third row have a second shape that is different from the first shape. In an embodiment, the first shape is a hexagonal shape. In an embodiment, the second shape is a chevron or fluke shape. In an embodiment, the second shape is a diamond or spade shape. In an embodiment, the second shape is a palmate webbed-foot shape.

[0021] In an embodiment, the fixation region has exactly two rows of openings formed via a plurality of struts and a plurality of crowns.

[0022] In an embodiment, the fixation region includes at least two rows of cleats, each cleat extending outward from a crown of the fixation region to engage a heart tissue.

[0023] In an embodiment, the fixation region includes exactly three rows of cleats.

[0024] In an embodiment, the transcatheter heart valve prosthesis also includes a brim portion extending radially outward from the first end of the fixation region of the outer frame.

[0025] In an embodiment, the third outer diameter is substantially similar to the second outer diameter.

[0026] According to an embodiment hereof, a transcatheter heart valve prosthesis includes a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from an undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame, in the deployed state, having at least two rows of openings; and a prosthetic valve component disposed within and attached to the inner frame, wherein the outer frame comprises a plurality of connecting struts, wherein each of the pluralityof connecting struts radially extends from an inflow end of the outer frame and is attached to an outflow end of the inner frame.

[0027] In an embodiment, one of the at least two rows of openings of the outer frame is a first row of large openings comprising a first pattern shape; and wherein another of the at least two additional rows of openings is a second row of small openings comprising a second pattern shape, wherein the large openings are larger relative to the small openings.

[0028] In an embodiment, the first pattern shape and the second pattern shape are similar shapes.

[0029] In an embodiment, the first pattern shape is a spade shape.

[0030] In an embodiment, the first pattern shape and the second pattern shape are different shapes.

[0031] In an embodiment, each of the large openings comprises a cleat extending therefrom.

[0032] In an embodiment, each of the small openings comprises a cleat extending therefrom.

[0033] In an embodiment, an area of the large openings is in the range of 300% to 700% larger than an area of the small openings.

[0034] In an embodiment, the plurality of connecting struts are arranged such that the outflow end of the inner frame is disposed proximal of an outflow end of the outer frame when the prosthesis is in the deployed state.

[0035] In an embodiment, the plurality of connecting struts are arranged such that the outflow end of the inner frame is disposed distal to an outflow end of the outer frame when the prosthesis is in the deployed state.

[0036] In an embodiment, each of the connecting struts are predominantly straight.

[0037] In an embodiment, each of the connecting struts are predominantly straight along their entire length.

[0038] In an embodiment, each opening of the at least two rows of openings of the inner frame are formed in a hexagonal shape.

[0039] In an embodiment, exactly two connecting struts are attached to each endmost outflow crown on the inner frame.

[0040] In an embodiment, the outer frame comprises a flared portion, wherein a diameter of the flared portion increases towards the outflow end.

[0041] In an embodiment, the outer frame has a substantially constant diameter along its entire length.

[0042] According to another embodiment hereof, a transcatheter heart valve prosthesis includes a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from undeployed state to a deployed state; the inner frame further comprising a cylindrical portion, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame comprising a cylindrical portion, in the deployed state, having at least two rows of openings; and a prosthetic valve component disposed within and attached to the inner frame, wherein the inner frame further comprises a plurality of first connecting member, each second connecting member extending radially outwards towards the outer frame, wherein the outer frame further comprises a plurality of second connecting members, each first connecting member extending radially inwards towards the inner frame, wherein each of the plurality of first connecting members is attached to a respective second connecting member.

[0043] In an embodiment, the connection of the plurality of first connecting members and the plurality of second connecting members form a plurality of respective attachment points disposed radially in-between the cylindrical portion of the inner frame and the cylindrical portion of the outer frame.

[0044] In an embodiment, the plurality of second connecting members are disposed at an inflow end of the outer frame.

[0045] In an embodiment, the plurality of first connecting members are disposed at a midportion of the inner frame.

[0046] In an embodiment, a portion of the inner frame disposed downstream of the first connecting members comprises an uncovered portion.

[0047] In an embodiment, the plurality of second connecting members are disposed at an outflow end of the outer frame.

[0048] In an embodiment, the plurality of first connecting members are disposed at an outflow end of the inner frame.

[0049] In another embodiment hereof, a transcatheter heart valve prosthesis includes a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, in the deployed state, comprising at least two rows of openings including a first row of openings at an outflow end of the outer frame, and a prosthetic valve component disposed within and attached to the inner frame, wherein at least the first row of openings comprises a first pattern shape for each of its openings, wherein the first pattern shape is partially formed by a pair of axial struts which extend along a longitudinal axis, and a pair of struts forming a chevron, the chevron extending between the pair of axial struts, wherein the chevron is configured to flare radially outward from the outflow end of the outer frame.

[0050] In an embodiment, each chevron comprises a cleat at a tip of the chevron.

[0051] In an embodiment, at least two of the rows of openings comprises the first pattern shape for each of its openings.

[0052] In an embodiment, all of the rows of openings comprise the first pattern shape for each of their openings.

[0053] In an embodiment, the first pattern shape comprises a second pair of struts connected to the pair of struts, forming a double chevron extending between the pair of axial struts.

[0054] In an embodiment, the rest of the several rows of openings comprises a second pattern shape for each of its openings.

[0055] According to an embodiment hereof, a transcatheter heart valve prosthesis includes a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from an undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame, in the deployed state, having at least a first row of openings and a second row of openings, the second row of openings being closer to an outflow end of the outer frame; and a prosthetic valve component disposed within and attached to the inner frame, wherein the outer frame comprises a plurality of connector struts, wherein each of the plurality of connector struts radially extends from a midportion of the outer frame and is attachedto an outflow end of the inner frame, and wherein the second row of openings includes a plurality of hanging fixation cells that are longitudinally aligned and radially outwardly offset from the plurality of connector struts, the hanging fixation cells being disconnected from, and not directly attached to, the outflow end of the inner frame.

[0056] In an embodiment, the inner frame is substantially cylindrical along its length and the outer frame comprises a tapered portion, wherein a diameter of the tapered portion decreases towards the outflow end thereof.

[0057] In an embodiment, a fixation region of the outer frame includes exactly three rows of openings including the first row of openings, the second row of openings, and an intermediate row of openings disposed between the first and second rows of openings, and wherein a cylindrical portion of the outer frame includes the first row of openings and a tapered portion of the outer frame includes the second row of openings, while the intermediate row of openings is within both the cylindrical portion and the tapered portion.

[0058] In an embodiment, all openings of the first row of openings, the second row of openings, and the intermediate row of openings are substantially the same shape.

[0059] In an embodiment, the shape is a diamond or a hexagonal shape.

[0060] In an embodiment, the outer frame further includes an outflow support ring having a plurality of struts and a plurality of crowns, each crown being formed between a pair of struts, and wherein a first set of the plurality of crowns are attached to the connector struts and a second set of the plurality of crowns are attached to the hanging fixation cells.

[0061] In an embodiment, the first set of the plurality of crowns are spaced radially inwards relative to the second set of the plurality of crowns.

[0062] In an embodiment, each hanging fixation cell of the plurality of hanging fixation cells includes a cleat extending radially outwards and / or upstream from an outer surface of the outer frame.

[0063] In an embodiment, the plurality of hanging fixation cells form an uncovered portion of the outer frame that does not receive a sealing component.

[0064] In an embodiment, each connector strut of the plurality of connector struts is substantially straight.

[0065] In an embodiment, the plurality of connector struts are integrally formed with the outer frame.

[0066] In an embodiment, each connector strut of the plurality of connector struts is circumferentially disposed between a pair of adjacent hanging fixation cells of the plurality of hanging fixation cells.

[0067] In an embodiment, the outer frame includes exactly two rows of openings including the first row of openings and the second row of openings, and wherein a cylindrical portion of the outer frame includes the first row of openings and the second row of openings is within the cylindrical portion and a tapered portion of the outer frame.

[0068] In an embodiment, each opening of the first row of openings is formed in a diamond or hexagonal shape, and each opening of the first row of openings is the same size.

[0069] In an embodiment, the second row of openings includes first openings and second openings formed in a diamond or hexagonal shape, with the first openings being relatively larger than the second openings, and wherein the first openings form the hanging fixation cells of the outer frame.

[0070] In an embodiment, each hanging fixation cell of the plurality of hanging fixation cells includes a cleat extending radially outwards and / or upstream from an outer surface of the outer frame.

[0071] In an embodiment, the outer frame includes exactly three hanging fixation cells.

[0072] In an embodiment, the exactly three hanging fixation cells are circumferentially spaced apart around a circumference of the outer frame at approximately equally spaced intervals.

[0073] In an embodiment, the outer frame further includes an outflow support ring having a plurality of struts and a plurality of crowns, each crown being formed between a pair of struts, and wherein the outflow support ring is attached to and extends distally from outflow ends of the connector struts.

[0074] In an embodiment, the outer frame includes at least two rows of cleats that extend upstream and / or radially outward from an outer surface of the outer frame.

[0075] In an embodiment, the outer frame includes exactly one row of barbs that extend upstream and / or radially outward from an outer surface of the outer frame, each barb having a v- shaped configuration with a first leg, a second leg, and an apex formed between the first and second legs, and wherein the apex of each barb is radially spaced apart from the outer surface of the outer frame when deployed.

[0076] In an embodiment, each barb is configured to extend substantially transverse to blood flow when deployed.

[0077] In an embodiment, the outer frame further includes at least one row of cleats that extend upstream and / or radially outward from an outer surface of the outer frame.

[0078] In an embodiment, the outer frame further includes exactly two row of cleats that extend upstream and / or radially outward from an outer surface of the outer frame.

[0079] In an embodiment, the at least one row of cleats is disposed upstream of the one row of barbs.

[0080] In an embodiment, each barb of the one row of barbs is longer than each cleat of the at least one row of cleats.

[0081] In an embodiment, a length of each barb of the one row of barbs is at least twice a length of each cleat of the at least one row of cleats.

[0082] According to an embodiment hereof, a transcatheter heart valve prosthesis includes a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from an undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame, in the deployed state, having at least a first row of openings and a second row of openings, the first row of openings being closer to an inflow end of the outer frame; and a prosthetic valve component disposed within and attached to the inner frame, wherein the first row of openings includes a plurality of flared cells and a plurality of tapered cells, with each flared cell of the plurality of flared cells being disposed between a pair of adjacent tapered cells of the plurality of tapered cells and each tapered opening of the plurality of tapered cells being disposed between a pair of adjacent flared cells of the plurality of flared cells, and wherein the outer frame comprises a plurality of connector struts, each connector strut of the plurality of connector struts radially extending from an inflow end of a tapered cell of the plurality of tapered cells to an inflow end of the inner frame, and wherein the outer frame comprises a plurality of downstream-extending cleats, each downstream-extending cleat extending from an inflow end of a flared cell of the plurality of flared cells towards an outflow end of the outer frame.

[0083] In an embodiment, the inner frame is substantially cylindrical along its length and the outer frame comprises a tapered portion at an inflow end of the outer frame.

[0084] In an embodiment, the inner frame comprises a flared portion at an inflow end of the inner frame and the outer frame comprises a tapered portion at an inflow end of the outer frame.

[0085] In an embodiment, the outer frame further includes an inflow support ring at an inflow end of the outer frame, the inflow support ring having a plurality of struts and a plurality of crowns, each crown being formed between a pair of struts.

[0086] In an embodiment, the outer frame further comprises a plurality of upstreamextending cleats, and each opening of the second row of openings includes an upstream-extending cleat of the plurality of upstream-extending cleats, each upstream-extending cleat extending radially outwards and towards an inflow end of the outer frame.

[0087] In an embodiment, the outer frame further includes a third row of openings disposed between the first row of openings and the second row of openings and each opening of the third row of openings includes an upstream-extending cleat of the plurality of upstream-extending cleats.

[0088] In an embodiment, each flared cell of the plurality of flared cells includes an upstream-extending cleat of the plurality of upstream-extending cleats and each tapered cell of the plurality of tapered cells includes an upstream-extending cleat of the plurality of upstreamextending cleats.

[0089] In an embodiment, each connector strut of the plurality of connector struts is substantially straight.

[0090] In an embodiment, the plurality of connector struts are integrally formed with the outer frame.

[0091] In an embodiment, each flared cell of the plurality of flared cells includes four struts, two adjacent endmost struts of the four struts which are closest to an outflow end of the outer frame being oriented substantially parallel to a longitudinal axis of the transcatheter heart valve prosthesis and two adjacent endmost struts of the four struts which are closest to an inflow end of the outer frame being oriented to extend radially outwards relative to the longitudinal axis of the transcatheter heart valve prosthesis.

[0092] In an embodiment, a downstream half of each flared cell of the plurality of flared cells is oriented substantially parallel to a longitudinal axis of the transcatheter heart valve prosthesis while an upstream half of each flared cell of the plurality of flared cells is oriented to extend radially outwards relative to the longitudinal axis of the transcatheter heart valve prosthesis.

[0093] In an embodiment, each tapered cell of the plurality of tapered cells includes four struts, two adjacent endmost struts of the four struts which are closest to an outflow end of the outer frame being oriented substantially parallel to a longitudinal axis of the transcatheter heart valve prosthesis and two adjacent endmost struts of the four struts which are closest to an inflow end of the outer frame being oriented to extend radially inwards relative to the longitudinal axis of the transcatheter heart valve prosthesis.

[0094] In an embodiment, a downstream half of each tapered cell of the plurality of tapered cells is oriented substantially parallel to a longitudinal axis of the transcatheter heart valve prosthesis while an upstream half of each tapered cell of the plurality of tapered cells is oriented to extend radially inwards relative to the longitudinal axis of the transcatheter heart valve prosthesis.

[0095] In an embodiment, the plurality of connector struts extend at an angle relative to a longitudinal axis of the transcatheter heart valve prosthesis to form a tapered portion of the outer frame, the angle being between 50° and 80° relative to the longitudinal axis.

[0096] In an embodiment, the outer frame includes a total of twelve connector struts, twelve tapered cells and twelve flared cells.

[0097] In an embodiment, the outer frame has a flared portion at an outflow end thereof, and the diameter of the flared portion increases towards the outflow end of the outer frame.

[0098] In an embodiment, the outer frame comprises a tapered portion at an inflow end thereof, and the diameter of the tapered portion decreases towards the inflow end of the outer frame.Brief Description of the Drawings

[0099] The accompanying figures, which are incorporated herein, form part of the specification and illustrate embodiments of a delivery system. Together with the description, the figures further explain the principles of and enable a person skilled in the relevant arts to make, use, and implant the prosthesis described herein. In the drawings, like reference numbers indicate identical or functionally similar elements.

[0100] FIG. 1 depicts a schematic view of a transcatheter heart valve prosthesis according to an aspect of the present disclosure implanted within a native mitral heart valve, the transcatheter heart valve prosthesis having a dual frame stent structure.

[0101] FIG. 2A is a side view of a transcatheter heart valve prosthesis having a dual frame stent structure according to a first embodiment hereof.

[0102] FIG. 2B is a perspective view of the dual frame stent structure of FIG. 2A.

[0103] FIG. 2C is a top view of the dual frame stent structure of FIG. 2A.

[0104] FIG. 2D is a side view of an inner frame of the dual frame stent structure of FIG.2A.

[0105] FIG. 2E is a perspective view of the inner frame of the dual frame stent structure of FIG. 2A.

[0106] FIG. 2F is a top view of the inner frame of the dual frame stent structure of FIG. 2A.

[0107] FIG. 2G is an enlarged side view of a single opening of a first or second row of openings of the inner frame of the dual frame stent structure of FIG. 2 A.

[0108] FIG. 2H is an enlarged side view of a single opening of a third row of openings of the inner frame of the dual frame stent structure of FIG. 2 A.

[0109] FIG. 21 is an enlarged side view of a single opening of a first or second row of openings of an outer frame of the dual frame stent structure of FIG. 2A.

[0110] FIG. 3A is a side view of an embodiment of a dual frame stent structure according to a second embodiment hereof.

[0111] FIG. 3B is a perspective view of the dual frame stent structure of FIG. 3 A.

[0112] FIG. 3C is a top view of the dual frame stent structure of FIG. 3A.

[0113] FIG. 3D is a side view of an inner frame of the dual frame stent structure of FIG. 3A.

[0114] FIG. 3E is a perspective view of the inner frame of the dual frame stent structure of FIG. 3A.

[0115] FIG. 3F is a top view of the inner frame of the dual frame stent structure of FIG. 3A.

[0116] FIG. 3G is an enlarged side view of a single opening of a first or second row of openings of the inner frame of the dual frame stent structure of FIG. 3 A.

[0117] FIG. 3H is an enlarged side view of a single opening of a third row of openings of the inner frame of the dual frame stent structure of FIG. 3 A.

[0118] FIG. 4A is a side view of an embodiment of a dual frame stent structure according to a third embodiment hereof.

[0119] FIG. 4B is a perspective view of the dual frame stent structure of FIG. 4A.

[0120] FIG. 4C is a top view of the dual frame stent structure of FIG. 4A.

[0121] FIG. 4D is a side view of an inner frame of the dual frame stent structure of FIG.4A.

[0122] FIG. 4E is a perspective view of the inner frame of the dual frame stent structure of FIG. 4A.

[0123] FIG. 4F is a top view of the inner frame of the dual frame stent structure of FIG. 4A.

[0124] FIG. 4G is an enlarged side view of a single opening of a first or second row of openings of the inner frame of the dual frame stent structure of FIG. 4 A.

[0125] FIG. 4H is an enlarged side view of a single opening of a third row of openings of the inner frame of the dual frame stent structure of FIG. 4 A.

[0126] FIG. 5A is a side view of a dual frame stent structure according to a fourth embodiment hereof.

[0127] FIG. 5B is a schematic side view of the dual frame stent structure of FIG. 5 A.

[0128] FIG. 6A is a side view of an embodiment of the dual frame stent structure according to a fifth embodiment hereof.

[0129] FIG. 6B is a schematic view of the dual frame stent structure of FIG. 6A.

[0130] FIG. 7 is a side view of the dual frame stent structure of FIG. 2A including a brim radially extending from an inflow end of a fixation region of the outer frame.

[0131] FIG. 8A is a side view of an embodiment of a dual frame stent structure according to a sixth embodiment hereof.

[0132] FIG. 8B is a perspective view of the dual frame stent structure of FIG. 8A.

[0133] FIG. 8C is a top view of the dual frame stent structure of FIG. 8A.

[0134] FIG. 8D is a top view of an outer frame of the dual frame stent structure of FIG.8A, wherein the outer frame is in its as-formed or as-cut configuration and is laid flat for illustrative purposes only.

[0135] FIG. 8E is a perspective view of the outer frame of the dual frame stent structure of FIG. 8A.

[0136] FIG. 8F is a perspective view of an inner frame of the dual frame stent structure of FIG. 8A.

[0137] FIG. 9 is a side view of an embodiment of a dual frame stent structure according to a seventh embodiment hereof.

[0138] FIG. 10 is a side view of an embodiment of a dual frame stent structure according to an eighth embodiment hereof.

[0139] FIG. 11 A is a side view of an embodiment of a dual frame stent structure according to a ninth embodiment hereof.

[0140] FIG. 1 IB is a side sectional view of the dual frame stent structure of FIG. HA.

[0141] FIG. 11C is a top view of the dual frame stent structure of FIG. 11A.

[0142] FIG. 1 ID is a top view of a portion of an outer frame of the dual frame stent structure of FIG. HA, wherein the portion of the outer frame is in its as-formed or as-cut configuration and is laid flat for illustrative purposes only.

[0143] FIG. 1 IE is a top view of a portion of an outer frame of a dual frame stent structure according to another embodiment hereof, wherein the portion of the outer frame is in its as-formed or as-cut configuration and is laid flat for illustrative purposes only.

[0144] FIG. 12A is a side sectional view of an embodiment of a dual frame stent structure according to a tenth embodiment hereof.

[0145] FIG. 12B is a top view of a portion of an outer frame of the dual frame stent structure of FIG. 12A, wherein the portion of the outer frame is in its as-formed or as-cut configuration and is laid flat for illustrative purposes only.

[0146] FIG. 13 A is a side view of an embodiment of an outer frame for use in a dual frame stent structure according to any embodiment hereof, wherein the outer frame includes a migration resistance feature according to a first embodiment hereof.

[0147] FIG. 13B is an enlarged view of the migration resistance feature of FIG. 13A.

[0148] FIG. 14A is a side view of an embodiment of an outer frame for use in a dual frame stent structure according to any embodiment hereof, wherein the outer frame includes a migration resistance feature according to a second embodiment hereof.

[0149] FIG. 14B is an enlarged view of the migration resistance feature of FIG. 14A.

[0150] FIG. 15 is a side view of an embodiment of an outer frame for use in a dual frame stent structure according to any embodiment hereof, wherein the outer frame includes a migration resistance feature according to a third embodiment hereof.

[0151] FIG. 16 is an enlarged view of a migration resistance feature according to a fourth embodiment hereof.

[0152] FIG. 17 is a side view of an embodiment of a dual frame stent structure according to an eleventh embodiment hereof.

[0153] FIG. 18A is a side view of an embodiment of a dual frame stent structure according to an eleventh embodiment hereof, wherein an inner frame of the dual frame stent structure is omitted for sake of illustration only.

[0154] FIG. 18B is a top view of the dual frame stent structure of FIG. 18 A.

[0155] FIG. 18C is a sectional view of the dual frame stent structure of FIG. 18A, taken along line C-C of FIG. 18B.

[0156] FIG. 18D is a sectional view of the dual frame stent structure of FIG. 18A, taken along line D-D of FIG. 18B.

[0157] FIG. 18E is a sectional view of the dual frame stent structure of FIG. 18A, taken along line E-E of FIG. 18B.

[0158] FIG. 18F is a top view of a portion of an outer frame of the dual frame stent structure of FIG. 18A, wherein the portion of the outer frame is in its as-formed or as-cut configuration and is laid flat for illustrative purposes only.

[0159] FIG. 19A is a side view of an embodiment of a dual frame stent structure according to a twelfth embodiment hereof, wherein an inner frame of the dual frame stent structure is omitted for sake of illustration only.

[0160] FIG. 19B is a sectional view of the dual frame stent structure of FIG. 19A, taken along line B-B of FIG. 19A.

[0161] FIG. 19C is a sectional view of the dual frame stent structure of FIG. 19A, taken along line C-C of FIG. 19A.

[0162] FIG. 19D is a top view of a portion of an outer frame of the dual frame stent structure of FIG. 19A, wherein the portion of the outer frame is in its as-formed or as-cut configuration and is laid flat for illustrative purposes only.

[0163] FIG. 20 A is a side view of an embodiment of a dual frame stent structure according to a thirteenth embodiment hereof, wherein an inner frame of the dual frame stent structure is omitted for sake of illustration only.

[0164] FIG. 20B is a sectional view of the dual frame stent structure of FIG. 20A, taken along line B-B of FIG. 20A.

[0165] FIG. 20C is a sectional view of the dual frame stent structure of FIG. 20A, taken along line C-C of FIG. 20A.

[0166] FIG. 20D is a top view of a portion of an outer frame of the dual frame stent structure of FIG. 20A, wherein the portion of the outer frame is in its as-formed or as-cut configuration and is laid flat for illustrative purposes only.

[0167] FIG. 21A is a perspective view of an embodiment of an outer frame for use in any of the dual frame stent structures of FIGS. 18A-20D.

[0168] FIG. 2 IB is a top view of a portion of an outer frame of the outer frame of FIG. 21 A, wherein the portion of the outer frame is in its as-formed or as-cut configuration and is laid flat for illustrative purposes only.

[0169] FIG. 22A is a side sectional view of an embodiment of transcatheter heart valve prosthesis having a barb for use in any of the dual frame stent structures of FIGS. 18A-21B.

[0170] FIG. 22B is a top view of a portion of an outer frame of the outer frame of FIG. 22A, wherein the portion of the outer frame is in its as-formed or as-cut configuration and is laid flat for illustrative purposes only.

[0171] FIG. 23A is a side view of an embodiment of a dual frame stent structure according to a fourteenth embodiment hereof, the dual frame stent structure including an outer frame and an inner frame.

[0172] FIG. 23B is a top view of the dual frame stent structure of FIG. 23 A.

[0173] FIG. 23C is a perspective view of the inner frame of the dual frame stent structure of FIG. 23 A.

[0174] FIG. 23D is a side view of the outer frame of the dual frame stent structure of FIG. 23 A.

[0175] FIG. 23E is a top view of the outer frame of FIG. 23 A, wherein the outer frame is in its as-formed or as-cut configuration and is laid flat for illustrative purposes only.

[0176] FIG. 23F is an enlarged view of a portion of FIG. 23E.

[0177] FIG. 24 A is a side view of an embodiment of a dual frame stent structure according to a fifteenth embodiment hereof, the dual frame stent structure including an outer frame and an inner frame.

[0178] FIG. 24B is a side view of the inner frame of the dual frame stent structure of FIG. 24A.Detailed Description of the Invention

[0179] Specific embodiments of the present invention are now described with reference to the figures, wherein like reference numbers indicate identical or functionally similar elements. Unless otherwise indicated, the terms “distal” and “proximal”, when used in the following description to refer to a shaft, a sheath, or a delivery device, are with respect to a position or direction relative to the treating clinician. Thus, “distal” and “distally” refer to positions distant from, or in a direction away from the treating clinician, and the terms “proximal” and “proximally” refer to positions near, or in a direction toward the treating clinician. The terms “distal” and “proximal”, when used in the following description to refer to a device to be implanted into a vessel, such as a heart transcatheter heart valve prosthesis, are used with reference to the direction of blood flow. Thus, “distal” and “distally” refer to positions in a downstream direction with respect to the direction of blood flow, and the terms “proximal” and “proximally” refer to positions in an upstream direction with respect to the direction of blood flow.

[0180] In addition, the term “self-expanding” is used in the following description with reference to one or more stent structures of the prostheses hereof and is intended to convey that the structures are shaped or formed from a material that can be provided with a mechanical memory to return the structure from a radially compressed or constricted radially compressed configuration to a radially expanded deployed configuration. Non-exhaustive illustrative self-expanding materials include stainless steel, a pseudo-elastic metal such as a nickel titanium alloy or nitinol, various polymers, or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal. Mechanical memory may be imparted to a wire or stent structure by thermal treatment to achieve a spring temper in stainless steel, for example, or to set a shape memory in a susceptible metal alloy, such as nitinol. Various polymers that can be made to have shape memory characteristics may also be suitable for use in embodiments hereof to include polymers such as polynorborene, trans-polyisoprene, styrene-butadiene, and polyurethane. As wellpoly L-D lactic copolymer, oligo caprylactone copolymer and poly cyclo-octine can be used separately or in conjunction with other shape memory polymers.

[0181] Embodiments hereof relate to transcatheter heart valve prostheses for implantation within a body or lumen that comprises a dual frame stent structure with an atrialized inner frame. As discussed in the Background section above, it is desirable for a transcatheter heart valve prosthesis implanted at a native mitral valve to avoid the left ventricular outflow tract obstruction (LVOTO) and to increase migration resistance. Dual frame stent structures of the transcatheter heart valve prostheses described herein are configured to improve migration resistance without negatively impacting LVOTO. FIG. 1 illustrates a profile of a transcatheter heart valve prosthesis 100 including a dual frame stent structure 110 according to an embodiment hereof implanted within a native mitral valve MV. FIG. 1 illustrates the transcatheter heart valve prosthesis 100 having an inflow end 102 and an outflow end 104 implanted within a target diseased native mitral valve MV that extends between a patient’s atrium A and a patient’s left ventricle LV. The dual frame stent structure 110 comprises an inner frame 140 and an outer frame 120 which circumferentially surrounds at least a portion of the inner frame 140. The inner frame 140 includes a cylindrical portion 142 and a flared portion 144 extending distally and radially outward from a distal or downstream end of the cylindrical portion 142. The outer frame 120 includes a cylindrical fixation region 122 which is attached to a distal or outflow end of the flared portion 144 of the inner frame 140. The outer frame 120 may further include a flange or brim 124 extending radially outward from a proximal or inflow end of the fixation region 122 of the outer frame 120. The brim 124 is described in more detail herein with respect to FIG. 7.

[0182] As shown in FIG. 1, when the transcatheter heart valve prosthesis 100 is deployed within the annulus of the native mitral valve, the dual frame stent structure 110 is configured to be expanded within native valve leaflets NL of the patient's defective native mitral valve MV, to thereby retain the native valve leaflets NL in a permanently open state. The cylindrical portion 142 of the inner frame 140 is configured to extend or be disposed at least partially within the patient’s atrium A of the heart. The flared portion 144 of the inner frame 140, as well as the fixation region 122 of the outer frame 120, are configured for implantation within or below an annulus of the native mitral valve, i.e., within the native valve leaflets NL. Accordingly, the transcatheter heart valve prosthesis 100 is implanted in vivo such that the inflow end 102 of the transcatheter heart valve prosthesis 100 is disposed within and floats freely within the patient’s atrium A and theoutflow end 104 of the transcatheter heart valve prosthesis 100 is disposed within or below an annulus of the native mitral valve such that an outflow end 104 of the transcatheter heart valve prosthesis 100 does not extend or only minimally extends beyond the native leaflets NL of the native mitral valve MV. As such, the outflow end 104 of the transcatheter heart valve prosthesis 100 does not extend or only minimally extends into the patient’s left ventricle LV of the heart to avoid left ventricular outflow tract obstruction (LVOTO).

[0183] A prosthetic valve component 106 is disposed within and secured to the cylindrical portion 142 of the inner frame 140. Since the cylindrical portion 142 of the inner frame 140 is configured to extend or be disposed at least partially within the patient’s atrium A of the heart as described above, the prosthetic valve component 106 is configured for supra-annular placement within the native mitral valve MV such that the prosthetic valve component 106 sits upstream of or proximal to the native leaflets NL of the native mitral valve MV when implanted in vivo.

[0184] FIG. 2A-2F provide a more detailed view of a dual frame stent structure 210 of a transcatheter heart valve prosthesis 200 according to a first embodiment of the present invention. The transcatheter heart valve prosthesis 200 is configured for placement within a native atrioventricular valve and includes a downstream or distal end, referred to herein as an outflow end 204, and an upstream or proximal end, referred to herein as an inflow end 202. The transcatheter heart valve prosthesis 200 is configured to have a profile the same as or similar to the profile of the transcatheter heart valve prosthesis 100 of FIG. 1, such that the inflow end 202 of the transcatheter heart valve prosthesis 200 is disposed within and floats freely within a patient’s atrium A and the outflow end 204 of the transcatheter heart valve prosthesis 200 does not extend or only minimally extends into the patient’s left ventricle LV of the heart to avoid left ventricular outflow tract obstruction (LVOTO).

[0185] As described above with respect to the transcatheter heart valve prosthesis 100, the dual frame stent structure 210 comprises an inner frame 240 and an outer frame 220 which circumferentially surrounds at least a portion of the inner frame 240. The inner frame 240 includes a cylindrical portion 242 and a flared portion 244 extending distally and radially outward from a distal or downstream end of the cylindrical portion 242. The outer frame 220 includes a cylindrical fixation region 222 which is attached to a distal or downstream end of the flared portion 244 of the inner frame 240. The outer frame 220 may optionally include a flange or brim (not shown)extending radially outward from a proximal or upstream end of the fixation region 222 of the outer frame 220, as described in more detail herein with respect to FIG. 7.[001861 In embodiments hereof, both the inner frame 240 and the outer frame 220 are selfexpanding to return to a radially expanded state from a radially compressed state and may be made from materials such as, but not limited to stainless steel, a pseudo-elastic metal such as a nickel titanium alloy (e.g., NITINOL), or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal. “Self-expanding” as used herein means that a structure / component has a mechanical memory to return to the radially expanded configuration or state as described herein. Thus, the transcatheter heart valve prosthesis 200 has a radially compressed configuration (not shown) for delivery within a delivery system and the radially expanded configuration for deployment within an annulus of the native heart valve.

[0187] The transcatheter heart valve prosthesis 200 may also include one or more sealing members or skirts coupled to the inner and / or outer surfaces of the inner frame 240 and the outer frame 220. As shown in FIG. 2A, the transcatheter heart valve prosthesis 200 includes a first skirt 208 coupled to the inner frame 240 and a second skirt 209 coupled to the outer frame 220. The first skirt 208 and the second skirt 209 may be sutured, riveted, glued, bonded, mechanically interlocked, or otherwise fastened to the outer frame 220 and the inner frame 240, respectively. The first and second skirts 208, 209 are configured to prevent paravalvular leaks between the transcatheter heart valve prosthesis 200 and the native tissue and / or between the outer frame 220 and the inner frame 240. The first and second skirts 208, 209 may be formed from a low-porosity woven fabric, such as polyester, polyethylene terephthalate (PET), or polytetrafluoroethylene (PTFE), which creates a one-way fluid passage when attached to the frame. In one embodiment, the first and second skirts may be a knit or woven polyester, such as a polyester or PTFE knit, which can be utilized when it is desired to provide a medium for tissue ingrowth and the ability for the fabric to stretch to conform to a curved surface. Polyester velour fabrics may alternatively be used, such as when it is desired to provide a medium for tissue ingrowth on one side and a smooth surface on the other side. Alternatively, the first and second skirts may be formed form a suitable natural or biological graft material such as pericardium or another membranous tissue including, but not limited to intestinal submucosa. The first and second skirts 208, 209 are illustrated in FIG. 2A, but are not shown in FIGS. 2B-2F for sake of clarity to better illustrate the structure of the dual frame stent structure 210.

[0188] As shown in FIG. 2A, the transcatheter heart valve prosthesis 200 further includes a prosthetic valve component 206 coupled to, mounted within, or otherwise carried by the inner frame 240. The prosthetic valve component 206 is configured as a one-way valve to allow blood flow in one direction (i.e., towards the outflow end 204) and thereby regulate blood flow therethrough. The prosthetic valve component 206 is capable of blocking flow in one direction to regulate flow therethrough via valve leaflets 207 that may form a bicuspid or tricuspid replacement valve. The valve leaflets 207 may be attached to the first skirt 208 which encloses or lines a portion of the inner frame 240 as would be known to one of ordinary skill in the art of prosthetic tissue valve construction. Particularly, along a margin of attachment MO A, the valve leaflets 207 are sutured or otherwise securely and sealingly attached along their bases to the interior surface of the first skirt 208, or otherwise attached to inner frame 240. Adjoining pairs of leaflets are attached to one another at their lateral ends to form commissures, and free or unattached edges of the valve leaflets 207 form coaptation edges of the prosthetic valve component 206. The prosthetic valve component 206 may be attached to the inner frame 240 and / or first skirt 208 in any suitable manner, including sutures, rivets, glue or adhesive, bonding, mechanically interlocking, or otherwise fastened together.

[0189] The valve leaflets 207 may be formed of various flexible materials including, but not limited to natural pericardial material such as tissue from bovine, equine or porcine origins, or synthetic materials such as polytetrafluoroethylene (PTFE), DACRON® polyester, pyrolytic carbon, or other biocompatible materials. With certain prosthetic leaflet materials, it may be desirable to coat one or both sides of the replacement valve leaflet with a material that will prevent or minimize overgrowth. It is further desirable that the prosthetic leaflet material is durable and not subject to stretching, deforming, or fatigue.

[0190] As stated above, the outer frame 220 includes the cylindrical fixation region 222. The cylindrical fixation region 222 has a cylindrical shape which is oriented to extend generally parallel to a longitudinal axis LA of the transcatheter heart valve prosthesis 200. The cylindrical fixation region 222 has an outer diameter D3 that is constant from a first or inflow end 236 of the fixation region 222 to a second or outflow end 238 of the fixation region 222, which defines the outflow end of the outer frame 220. The cylindrical fixation region 222 is configured to securely fix the outer frame 220 to engage heart tissue at or below an annulus of a native heart valve, such as an annulus of a native mitral valve. The cylindrical fixation region 222 may be configured toengage subannular tissue, such as inward-facing surfaces of the native valve leaflets. The cylindrical fixation region 222 functions as an anchor for the transcatheter heart valve prosthesis 200 to secure its deployed position within a native annulus. In an aspect of the disclosure, the cylindrical fixation region 222 includes one or more rows of cleats or prongs 226 that extend upstream or upward (towards the inflow end 202 of the transcatheter heart valve prosthesis 200) and / or radially outward from an outer wall or surface of the cylindrical fixation region 222 to engage heart tissue. The cleats 226 may be configured to penetrate the native tissue to facilitate retention or maintain position of the transcatheter heart valve prosthesis 200 in a desired implanted location. In another aspect of the disclosure, as an alternative to a cleat structure, the cylindrical fixation region 222 may employ barbs, spikes, or other tissue fixation mechanisms for engaging heart tissue. As shown in FIG. 2A-2B, in an embodiment, the outer frame 220 includes a total of three rows of cleats 226. More particularly, a first row of cleats 226 A is disposed at each distal - most crown of the first row of openings 228A (which form the endmost outflow crowns of the outer frame 220). A second row of cleats 226B is disposed at each distal-most crown of the second row of openings 228B. Lastly, a third row of cleats 226C is disposed at each proximal-most crown of the first row of openings 228A. The second row of cleats 226B is disposed between the first and third row of cleats 226 A, 226C. In another embodiment hereof, the outer frame 220 may include a total of two rows of cleats 226. Still in further embodiments, the outer frame 220 may include a single row of cleats 226.

[0191] The fixation region 222 of the outer frame 220 includes a plurality of openings 228 that are formed by a plurality of struts 230 and a plurality of crowns 232, with each crown 232 being formed between a pair of opposing struts 230. Each crown 232 is a curved segment or bend extending between opposing struts 230. In an embodiment, the fixation region 222 includes exactly two rows of openings 228, namely a first row of openings 228A and a second row of openings 228B. In an embodiment, the first row of openings 228A includes the same number of openings 228 as the second row of openings 228B. In an embodiment, all openings 228 of the first row of openings 228A and the second row of openings 228B are substantially the same size and shape. In an embodiment, all openings 228 of the first row of openings 228A and the second row of openings 228B are substantially diamond-shaped or spade-shaped. FIG. 21 illustrates an enlarged side view of a single opening 228 of the outer frame 220. As shown in FIG. 21, each opening 228 of the outer frame 220 is formed via by four struts 230 with each pair of struts 230 having a crown 232therebetween. A first pair of angled struts 230 extend distally from each other and angled outwardly away each other while a second pair of angled struts 230 extend distally from the second or outflow ends of the first pair of angled struts and angled inwardly towards each other. In an embodiment, the outer frame 220 has a total of twenty-four endmost crowns 232 at each of the inflow end 236 and the outflow end 238 of the outer frame 220. Stated another way, the distal- most crowns of the second row of openings 228B form the endmost outflow crowns of the outer frame 220 and the proximal-most crowns of the first row of openings 228A form the endmost inflow crowns of the outer frame 220. In an embodiment, every other endmost crown 232, or alternating crowns 232, at the outflow end 238 of the outer frame 220 includes an eyelet 239 formed thereon or attached thereto which is configured for attachment to the inner frame 240 as will be described in more detail herein.

[0192] The outer frame 220 may be formed by a laser-cut manufacturing method and / or other conventional frame forming methods. For example, the outer frame 220 may be laser cut from a single metal tube into the desired geometry, creating a tubular scaffold of interconnected struts and crowns that form the openings 228.

[0193] The inner frame 240 is shown removed from the transcatheter heart valve prosthesis 200 in FIGS. 2D-2F for sake of illustration only. The inner frame 240 defines a lumen 241 (best shown on FIG. 2F) from an inflow end 262 of the inner frame 240 to an outflow end 268 of the inner frame 240. The prosthetic valve component 206, described in detail above, is disposed within the lumen 241 of the inner frame. As described above, the inner frame 240 includes a cylindrical portion 242 and a flared portion 244. The cylindrical portion 242 has a cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 200. The cylindrical portion 242 has a first or upstream end 260 of the cylindrical portion 242 defining the inflow end 262 of the inner frame 240, as well as the inflow end 202 of the transcatheter heart valve prosthesis 200. The first or upstream end 260 of the cylindrical portion 242 defining the inflow end 262 of the inner frame 240 has an outer diameter DI. A second or downstream end 264 of the cylindrical portion 242 of the inner frame 240 is integrally formed with or coextensive with a first or upstream end 266 of the flared portion 244 of the inner frame 240, and a second or downstream end 267 of the flared portion 244 defines the outflow end 268 of the inner frame 240. In an embodiment, the second or downstream end 264 of the cylindrical portion 242 and the coextensive first or upstream end 266 of the flared portion 244 have the outer diameterDI such that the outer diameter of the cylindrical portion 242 may be described as being constant along the entire length thereof. The second or downstream end 267 of the flared portion 244 defining the outflow end 268 of the inner frame 240 has an outer diameter D2 that is greater than the outer diameter DI. Thus, the flared portion 244 flares radially, outwardly from the first end 266 having the outer diameter DI to the second end 267 having the outer diameter D2 such that the flared portion 244 has a generally frustoconical shape or profile. The outer diameter D2 of the outflow end 268 of the inner frame 240 is substantially similar to the outer diameter D3 of the outflow end 238 of the outer frame 220, as the outflow end 268 of the inner frame 240 abuts against an inner surface of the outer frame 220 at the outflow end 238 thereof and is attached to the outflow end 238 of the outer frame 220 as described in more detail below.

[0194] The inner frame 240 includes a plurality of openings 246. In an embodiment, the inner frame 240 includes exactly three rows of openings 246, namely a first row of openings 246A, a second row of openings 246B, and a third row of openings 246C. The first row of openings 246 A is formed at the inflow end 262 of the inner frame 240, the third row of openings 246C is formed at the outflow end 268 of the inner frame 240, and the second row of openings 246B extends between the first and third rows of openings 246A, 246C, respectively. In an embodiment, the cylindrical portion 242 of the inner frame 240 includes the first row of openings 246A and the flared portion 244 of the inner frame 240 includes the third row of openings 246C, while the second row of openings 246B is within both the cylindrical portion 242 and the flared portion 244. More particularly, in an embodiment, the two adjacent endmost struts 250 of each opening of the second row of openings 246B closest to the outflow end 268 are within the flared portion 244 of the inner frame 240.

[0195] In an embodiment, all openings 246 of the first row of openings 246A and the second row of openings 246B are substantially the same size and shape. The openings of the first row of openings 246A and the second row of openings 246B are formed with a shape pattern distinct from a shape pattern of the openings of the third row of openings 246C, as illustrated in FIGS. 2D-2F. In an embodiment, each opening 246 of the first row of openings 246 A and the second row of openings 246B is formed in a hexagonal shape and each opening 246 of the third row of openings 246C is formed in a fluke or chevron shape.

[0196] FIG. 2G illustrates an enlarged side view of a single opening of the first or second row of openings 246 A, 246B. As shown in FIG. 2G, each opening 246 of the first or second rowof openings 246A, 246B is formed by six struts 250 with each pair of struts 250 having a crown 252 therebetween. Two opposing struts 250 are substantially parallel to each other, and a first pair of angled struts 250 extend proximally from the first or inflow ends of the two opposing parallel struts 250 and are angled inwardly towards each other while a second pair of angled struts 250 extend distally from the second or outflow ends of the two opposing parallel struts 250 and are angled inwardly towards each other. In an embodiment, the inner frame 240 has a total of twelve endmost crowns 252 at the inflow end 262 of the inner frame 240. Stated another way, the proximal-most crowns of the first row of openings 246A form the endmost inflow crowns of the inner frame 240.

[0197] The outflow end 268 of the inner frame 240 includes a plurality of radially- extending segments 280 and an outflow ring 286 formed of a plurality of struts 288 and a plurality of crowns 289, with each crown 289 being formed between a pair of opposing struts 288. Each crown 289 is a curved segment or bend extending between opposing struts 288. The plurality of radially -extending segments 280 extends between endmost outflow crowns 252 of the second row of openings 246B and endmost outflow crowns 289 of the outflow ring 286. More particularly, each radially-extending segment 280 includes a first or upstream end 282 and a second or downstream end 284. The first end 282 of each radially-extending segment 280 is coextensive or integrally formed with an endmost outflow crown of an opening of the second row of openings 246B, and the second end 284 of each radially extending segment 280 is coextensive or integrally formed with an endmost outflow crown 289 of the outflow ring 286. Similar to the cylindrical portion 242 of the inner frame 240, the outflow ring 286 is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 200. The radially-extending segments 280, along with the two adjacent endmost struts 250 of the second row of openings 246B closest to the outflow end 268, do not extend parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 200 but rather flare radially outward.

[0198] FIG. 2H is an enlarged side view of a single opening of the third row of openings 246C. As shown in FIG. 2H, each opening 246 of the third row of openings 246C is formed in a shape that may be generally described as a chevron, fluke, or heart. More particularly, each opening 246 of the third row of openings 246C is formed via two adjacent struts 288 of the outflow ring 286, two adjacent endmost struts 250 of the second row of openings 246B closest to the outflow end 268, and two adjacent radially-extending segments 280. In an embodiment, the innerframe 240 has a total of twelve endmost crowns at the outflow end 268 of the inner frame 240 which are formed by the endmost or distal-most outflow crowns 289 of the outflow ring 286. In an embodiment, every endmost crown 289 at the outflow end 268 of the inner frame 240 includes an eyelet 259 formed thereon or attached thereto which is configured for attachment to the outer frame 220 as will be described in more detail herein.

[0199] The outer frame 220 and the inner frame 240 are attached to each other at respective outflow ends 238, 268 thereof. More particularly, the second or outflow end 238 of the cylindrical fixation region 222 of the outer frame 220 is attached to the outflow end 268 of the inner frame 240. In the embodiment shown, the inner frame 240 includes a plurality of eyelets 259 formed integrally with the endmost or distal-most outflow crowns 289 of the outflow ring 286 and the outer frame 220 includes a plurality of 268 formed integrally with the endmost or distal-most outflow crowns 232 of the cylindrical fixation region 222 of the outer frame 220. Respective eyelets 239, 259 of the outer frame 220 and the inner frame 240 are aligned and attached via rivets (not shown) to formed a plurality of connection points 270 between the outer frame 220 and the inner frame 240 together. However, in other embodiments, threads, adhesives, solder, laser welding, metal bolts or other mechanical features, or other types of fasteners can be used to secure the inner frame 240 to the outer frame 220.

[0200] In an embodiment, the outer frame 220 and the inner frame 240 are attached to each other at exactly twelve connection points 270. In an embodiment, a ratio of the endmost outflow crowns 232 of the outer frame 220 to the endmost outflow crowns 289 of the inner frame 240 is 2: 1. More particularly, every other crown 232, or alternating crowns 232, at the outflow end 238 of the outer frame 220 is configured to connect or be attached to a crown 289 at the outflow end 268 of the inner frame 240 via respective eyelets 239, 259 which are further sutured, riveted, glued, bonded, mechanically interlocked, or otherwise fastened to each other. By having these connection points 270 at the outflow ends 238, 268 of the outer and inner frames 220, 240, respectively, the geometry of the flared portion 244 of the inner frame 240, and the geometry of the outer frame 220 allow for increased stent structure durability, i.e. greater capabilities in dealing with high stress or high load applied against the transcatheter heart valve prosthesis 200 without succumbing to breakage, deformation, or overall deterioration of the integrity of the dual frame stent structure 210, that otherwise may result from loading the transcatheter heart valve prosthesis 200 into a delivery system (not shown), deploying the transcatheter heart valve prosthesis 200 from saiddelivery system, or from continual forces applied to the transcatheter heart valve prosthesis 200 while implanted within the patient’s heart.

[0201] With reference to FIG. 2A and 2B, when the dual frame stent structure 210 is in its radially expanded configuration, the first or inflow end 236 of the cylindrical fixation region 222 of the outer frame 220 is radially spaced from the inner frame 240. As such, forces from the native anatomy during operation of the native valve after the transcatheter heart valve prosthesis 200 has been implanted are primarily absorbed by the outer frame 220 such that the inner frame 240 and the prosthetic valve component 206 coupled thereto remain substantially undeformed. In other words, the inner frame 240 and prosthetic valve component 206 are effectively mechanically isolated from the distorting forces exerted on the outer frame 220 by the native tissue, e.g., radially compressive forces exerted by the native annulus and / or leaflets, longitudinal diastolic and systolic forces, hoop stress, etc.

[0202] As best illustrated in FIG. 2A, the cylindrical fixation region 222 of the outer frame 220 has a first length or height Hl from the first end 236 to the second end 238 thereof, and the inner frame 240 has a second length or height H2 from the inflow end 262 to the outflow end 268 thereof. In an embodiment, the second height H2 is between 0 % and 250 % longer than the first height Hl. In an embodiment, the height Hl of the outer frame 220 is relative to the height H2 of the inner frame 240 at a ratio of 1.0 : 2.5. Stated another way, the inner frame 240 may be up to 2.5 times taller than the outer frame 220, with the inner frame 240 being 2.5 times taller as the maximum condition and the inner frame 240 being the same size as the outer frame 220 being the minimum condition. In an embodiment, the height Hl of the outer frame 220 may be between 5mm - 35mm, and the height H2 of the inner frame 240 may be between 15mm - 100mm. Generally, the height Hl of the outer frame 220 is less than that of conventional transcatheter heart valve prostheses having dual frames configured for placement in a native mitral valve known to those having ordinary skill in the art. By shortening the height Hl of the outer frame 220, protrusion of the outer frame 220 into a ventricle of a native atrioventricular valve is prevented, and thus improving the uninterrupted flow of fluid through the transcatheter heart valve prosthesis 200 as shown and described herein.

[0203] FIGS. 3A-3H depict a transcatheter heart valve prosthesis 300 having a dual frame stent structure 310 according to a second embodiment hereof. Similar to the dual frame stent structure 210, the dual frame stent structure 310 includes an inner frame 340 and an outer frame320. The dual frame stent structure 310 is intended to form the scaffolding of a transcatheter heart valve prosthesis 300 having a prosthetic valve component (such as the prosthetic valve component 206) disposed within the inner frame 340. The dual frame stent structure 310 may also include one or more sealing members or skirts coupled to the inner and / or outer surfaces of the inner frame 340 and the outer frame 320, as similarly described with respect to the first and second skirts 208, 209 of the transcatheter heart valve prosthesis 200. The prosthetic valve component and skirts are not shown on FIGS. 3A-3H for sake of clarity, to better illustrate the configuration of the dual frame stent structure 310. The transcatheter heart valve prosthesis 300 is configured to have a profile the same as or similar to the profile of the transcatheter heart valve prosthesis 100 of FIG. 1, such that an inflow end 302 of the transcatheter heart valve prosthesis 300 is disposed within and floats freely within a patient’ s atrium A and an outflow end 304 of the transcatheter heart valve prosthesis 300 does not extend or only minimally extends into the patient’s left ventricle LV of the heart to avoid obstruction of the left ventricular outflow tract (LVOT).

[0204] Similar to the dual frame stent structure 210, both the inner frame 340 and the outer frame 320 are self-expanding to return to a radially expanded state from a radially compressed state and may be made from materials such as, but not limited to stainless steel, a pseudo-elastic metal such as a nickel titanium alloy (e.g. NITINOL), or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal. The outer frame 320 of the dual frame stent structure 310 circumferentially surrounds at least a portion of the inner frame 340. The outer frame 320 of the dual frame stent structure 310 is the same as the outer frame 220 of the dual frame stent structure 210, and as such the details of the outer frame 320 need not be repeated herein for sake of brevity. For sake of consistency, the last two digits of the reference numbers of the outer frame 220 coincide with the last two digits of the reference numbers pertaining to the outer frame 320. Thus, the outer frame 320 includes a cylindrical fixation region 322 having a first or inflow end 336 and a second or outflow end 338, one or more rows of cleats or prongs 326, a plurality of openings 328 that are formed by a plurality of struts 330 and a plurality of crowns 332, and a plurality of eyelets 339 which correspond to or are the same as the cylindrical fixation region 222 having the first or inflow end 236 and the second or outflow end 238, one or more rows of cleats or prongs 226, the plurality of openings 228 that are formed by the plurality of struts 230 and the plurality of crowns 232, and the plurality of eyelets 239 of the outer frame 220 described above. The outer frame 320 may optionally include a flange or brim (not shown) extending radiallyoutward from a proximal or upstream end of the fixation region 322 of the outer frame 320, as described in more detail herein with respect to FIG. 7.

[0205] Similar to the previous embodiment, the inner frame 340 includes a cylindrical portion 342 and a flared portion 344 extending distally and radially outward from a distal or downstream end of the cylindrical portion 342. The cylindrical fixation region 322 of the outer frame 320 is attached to a distal or downstream end of the flared portion 344 of the inner frame 340.

[0206] The inner frame 340 is shown removed from the transcatheter heart valve prosthesis 300 in FIGS. 3D-3F for sake of illustration only. The inner frame 340 defines a lumen 341 (best shown on FIG. 3F) from an inflow end 362 of the inner frame 340 to an outflow end 368 of the inner frame 340. A prosthetic valve component (not shown) is disposed within the lumen 341 of the inner frame. The cylindrical portion 342 of the inner frame 340 has a substantially cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 300. The cylindrical portion 342 has a first or upstream end 360 defining the inflow end 362 of the inner frame 340, as well as the inflow end 303 of the transcatheter heart valve prosthesis 300. The first or upstream end 360 of the cylindrical portion 342 defining the inflow end 362 of the inner frame 340 has an outer diameter DI . A second or downstream end 364 of the cylindrical portion 342 of the inner frame 340 is integrally formed with or coextensive with a first or upstream end 366 of the flared portion 344 of the inner frame 340, and a second or downstream end 367 of the flared portion 344 defines the outflow end 368 of the inner frame 340. In an embodiment, the second or downstream end 364 of the cylindrical portion 342 and the coextensive first or upstream end 366 of the flared portion 344 have the outer diameter DI such that the outer diameter of the cylindrical portion 342 may be described as being constant along the entire length thereof. The second or downstream end 367 of the flared portion 344 defining the outflow end 368 of the inner frame 340 has an outer diameter D2 that is greater than the outer diameter DI. Thus, the flared portion 344 flares radially, outwardly from the first end 366 having the outer diameter DI to the second end 367 having the outer diameter D2 such that the flared portion 344 has a generally frustoconical shape or profile. The outer diameter D2 of the outflow end 368 of the inner frame 340 is substantially similar to the outer diameter of the outflow end 338 of the outer frame 320, as the outflow end 368 of the inner frame 340 abuts against an inner surfaceof the outer frame 320 at the outflow end 338 thereof and is attached to the outflow end 338 of the outer frame 320 as described in more detail below.

[0207] The inner frame 340 includes a plurality of openings 346 that are formed by a plurality of struts 350 and a plurality of crowns 352, with each crown 352 being formed between a pair of opposing struts 350. Each crown 352 is a curved segment or bend extending between opposing struts 350. In an embodiment, the inner frame 340 includes exactly three rows of openings 346, namely a first row of openings 346A, a second row of openings 346B, and a third row of openings 346C. The first row of openings 346A is formed at the inflow end 362 of the inner frame 340, the third row of openings 346C is formed at the outflow end 368 of the inner frame 340, and the second row of openings 346B extends between the first and third rows of openings 346A and 346C, respectively. In an embodiment, the cylindrical portion 342 of the inner frame 340 includes the first row of openings 346A and the flared portion 344 of the inner frame 340 includes the third row of openings 346C, while the second row of openings 346B is within both the cylindrical portion 342 and the flared portion 344. More particularly, in an embodiment, the two adjacent endmost struts 350 of the second row of openings 346B closest to the outflow end 368 are within the flared portion 344 of the inner frame.

[0208] In an embodiment, all openings 346 of the first row of openings 346A and the second row of openings 346B are substantially the same size and shape. The openings 346 of the first row of openings 346 A and the second row of openings 346B are formed with a shape pattern distinct from a shape pattern of the openings of the third row of openings 246C, as illustrated in FIGS. 2D-2F. In an embodiment, each opening 246 of the first row of openings 246A and the second row of openings 246B is formed in a hexagonal shape and each opening 246 of the third row of openings 246C is formed in a diamond shape or a spade shape. The third row of openings 346C, along with the two adjacent endmost struts 350 of the second row of openings 346B closest to the outflow end 368, do not extend parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 300 but rather flares radially outward.

[0209] FIG. 3G illustrates an enlarged side view of a single opening of the first or second row of openings 346 A, 346B. As shown in FIG. 3G, each opening 346 of the first row of openings 346A and / or the second row of openings 346B is formed by six struts 350 with each pair of struts 350 having a crown 352 therebetween. Two opposing struts 350 are substantially parallel to each other, and a first pair of angled struts 350 extend proximally from the first or inflow ends of thetwo opposing parallel struts 350 and are angled inwardly towards each other while a second pair of angled struts 350 extend distally from the second or outflow ends of the two opposing parallel struts 350 and are angled inwardly towards each other. In an embodiment, the inner frame 340 has a total of twelve endmost crowns 352 at the inflow end 362 of the inner frame 340. Stated another way, the proximal-most crowns of the first row of openings 346A form the endmost inflow crowns of the inner frame 340.

[0210] FIG. 3H is an enlarged side view of a single opening of the third row of openings 346C. As shown in FIG. 3H, each opening 346 of the third row of openings 346C is formed in a shape that may be generally described as a diamond or a spade shape. More particularly, each opening 346 of the third row of openings 346C is formed via by four struts 350 with each pair of struts 350 having a crown 352 therebetween. A first pair of angled struts 350 extend distally from each other and angled outwardly away each other while a second pair of angled struts 350 extend distally from the second or outflow ends of the first pair of angled struts and angled inwardly towards each other. In an embodiment, the inner frame 340 has a total of twelve endmost crowns at the outflow end 368 of the inner frame 340 which are formed by the endmost or distal-most outflow crowns 352 of the third row of openings 346C. In an embodiment, every endmost crown 352 at the outflow end 368 of the inner frame 340 includes an eyelet 359 formed thereon or attached thereto which is configured for attachment to the outer frame 320 as will be described in more detail herein.

[0211] The outer frame 320 and the inner frame 340 are attached to each other at respective outflow ends 338, 368 thereof. More particularly, the second or outflow end 338 of the cylindrical fixation region 322 of the outer frame 320 is attached to the outflow end 368 of the inner frame 340. In the embodiment shown, the inner frame 340 includes a plurality of eyelets 359 formed integrally with the endmost crowns 352 of the third row of openings 346C and the outer frame 320 includes a plurality of eyelets 339 formed integrally with the endmost or distal-most outflow crowns of the cylindrical fixation region 322 of the outer frame 320. Respective eyelets 339, 359 of the outer frame 320 and the inner frame 340 are aligned and attached via rivets (not shown) to form a plurality of connection points 370 between the outer frame 320 and the inner frame 340 together. However, in other embodiments, threads, adhesives, solder, laser welding, metal bolts or other mechanical features, or other types of fasteners can be used to secure the inner frame 340 to the outer frame 320.

[0212] In an embodiment, the outer frame 320 and the inner frame 340 are attached to each other at exactly twelve connection points 370. In an embodiment, a ratio of the endmost outflow crowns of the outer frame 320 to the endmost outflow crowns 352 of the inner frame 340 is 2: 1. More particularly, every other crown, or alternating crowns, at the outflow end 338 of the outer frame 320 is configured to connect or be attached to a crown 352 at the outflow end 368 of the inner frame 340 via respective eyelets 339, 359 which are further sutured, riveted, glued, bonded, mechanically interlocked, or otherwise fastened to each other. By having these connection points 370 at the outflow ends 338, 368 of the outer and inner frames 320, 340, respectively, the geometry of the flared portion 344 of the inner frame 340, and the geometry of the outer frame 320 allow for increased stent structure durability, i.e. greater capabilities in dealing with high stress or high load applied against the transcatheter heart valve prosthesis 300 without succumbing to breakage, deformation, or overall deterioration of the integrity of the dual frame stent structure 310, that otherwise may result from loading the transcatheter heart valve prosthesis 300 into a delivery system (not shown), deploying the transcatheter heart valve prosthesis 300 from said delivery system, or from continual forces applied to the transcatheter heart valve prosthesis 300 while implanted within the patient’s heart.

[0213] With reference to FIG. 3 A and 3B, when the dual frame stent structure 310 is in its radially expanded configuration, the first or inflow end 336 of the cylindrical fixation region 322 of the outer frame 320 is radially spaced from the inner frame 340. As such, forces from the native anatomy during operation of the native valve after the transcatheter heart valve prosthesis 300 has been implanted are primarily absorbed by the outer frame 320 such that the inner frame 340 and the prosthetic valve coupled thereto remain substantially undeformed. In other words, the inner frame 340 and the prosthetic valve coupled thereto are effectively mechanically isolated from the distorting forces exerted on the outer frame 320 by the native tissue, e.g., radially compressive forces exerted by the native annulus and / or leaflets, longitudinal diastolic and systolic forces, hoop stress, etc.

[0214] As best illustrated in FIG. 3 A, the cylindrical fixation region 322 of the outer frame 320 has a first length or height Hl from the first end 336 to the second end 338 thereof, and the inner frame 340 has a second length or height H2 from the inflow end 362 to the outflow end 368 thereof. In an embodiment, the second height H2 is between 0 % and 250 % longer than the first height Hl. In an embodiment, the height Hl of the outer frame 320 is relative to the height H2 ofthe inner frame 340 at a ratio of 1 .0 : 2.5. Stated another way, the inner frame 340 may be up to 2.5 times taller than the outer frame 320, with the inner frame 340 being 2.5 times taller as the maximum condition and the inner frame 340 being the same size as the outer frame 320 being the minimum condition. Generally, the height Hl of the outer frame 320 is less than that of conventional transcatheter heart valve prostheses having dual frames configured for placement in a native mitral valve known to those having ordinary skill in the art. By shortening the height Hl of the outer frame 320, protrusion of the outer frame 320 into a ventricle of a native atrioventricular valve is prevented, and thus improving the uninterrupted flow of fluid through the transcatheter heart valve prosthesis 300 as shown and described herein.

[0215] FIGS. 4A-4H depict a transcatheter heart valve prosthesis 400 including a dual frame stent structure 410 according to a third embodiment hereof. Similar to the dual frame stent structure 210, the dual frame stent structure 410 includes an inner frame 440 and an outer frame 420. The dual frame stent structure 410 is intended to form the scaffolding of a transcatheter heart valve prosthesis 400 having a prosthetic valve component (such as the prosthetic valve component 206) disposed within the inner frame 440. The dual frame stent structure 410 may also include one or more sealing members or skirts coupled to the inner and / or outer surfaces of the inner frame 440 and the outer frame 420, as similarly described with respect to the first and second skirts 208, 209 of the transcatheter heart valve prosthesis 200. The prosthetic valve component and skirts are not shown on FIGS. 4A-4H for sake of clarity, to better illustrate the configuration of the dual frame stent structure 410. The transcatheter heart valve prosthesis 400 is configured to have a profile the same as or similar to the profile of the transcatheter heart valve prosthesis 100 of FIG. 1, such that an inflow end 402 of the transcatheter heart valve prosthesis 400 is disposed within and floats freely within a patient’ s atrium A and an outflow end 404 of the transcatheter heart valve prosthesis 400 does not extend or only minimally extends into the patient’s left ventricle LV of the heart to avoid obstruction of the left ventricular outflow tract (LVOT).

[0216] Similar to the dual frame stent structure 210, both the inner frame 440 and the outer frame 420 are self-expanding to return to a radially expanded state from a radially compressed state and may be made from materials such as, but not limited to stainless steel, a pseudo-elastic metal such as a nickel titanium alloy (e.g. NITINOL), or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal. The outer frame 420 of the dual frame stent structure 410 circumferentially surrounds at least a portion of the inner frame 440. The outerframe 420 of the dual frame stent structure 410 is the same as the outer frame 220 of the dual frame stent structure 210, and as such the details of the outer frame 420 need not be repeated herein for sake of brevity. For sake of consistency, the last two digits of the reference numbers of the outer frame 220 coincide with the last two digits of the reference numbers pertaining to the outer frame 420. Thus, the outer frame 420 includes a cylindrical fixation region 422 having a first or inflow end 436 and a second or outflow end 438, one or more rows of cleats or prongs 426, a plurality of openings 428 that are formed by a plurality of struts 430 and a plurality of crowns 432, and a plurality of eyelets 439 which correspond to or are the same as the cylindrical fixation region 222 having the first or inflow end 236 and the second or outflow end 238, one or more rows of cleats or prongs 226, the plurality of openings 228 that are formed by the plurality of struts 230 and the plurality of crowns 232, and the plurality of eyelets 239 of the outer frame 220 described above. The outer frame 420 may optionally include a flange or brim (not shown) extending radially outward from a proximal or upstream end of the fixation region 422 of the outer frame 420, as described in more detail herein with respect to FIG. 7.

[0217] Similar to the previous embodiments hereof, the inner frame 440 includes a cylindrical portion 442 and a flared portion 444 extending distally and radially outward from a distal or downstream end of the cylindrical portion 442. The cylindrical fixation region 422 of the outer frame 420 is attached to a distal or downstream end of the flared portion 444 of the inner frame 440.

[0218] The inner frame 440 is shown removed from the transcatheter heart valve prosthesis 400 in FIGS. 4D-4F for sake of illustration only. The inner frame 440 defines a lumen 441 (best shown on FIG. 4F) from an inflow end 462 of the inner frame 440 to an outflow end 468 of the inner frame 440. A prosthetic valve component is disposed within the lumen 441 of the inner frame. As described above, the inner frame 440 includes a cylindrical portion 442 and a flared portion 444. The cylindrical portion 442 has a substantially cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 400. The cylindrical portion 442 has a first or upstream end 460 of the cylindrical portion 442 defining the inflow end 462 of the inner frame 440, as well as the inflow end 402 of the transcatheter heart valve prosthesis 400. The first or upstream end 460 of the cylindrical portion 442 defining the inflow end 462 of the inner frame 440 has an outer diameter D 1. A second or downstream end 464 of the cylindrical portion 442 of the inner frame 440 is integrally formed with or coextensive witha first or upstream end 466 of the flared portion 444 of the inner frame 440, and a second or downstream end 467 of the flared portion 444 defines the outflow end 468 of the inner frame 440. In an embodiment, the second or downstream end 464 of the cylindrical portion 442 and the coextensive first or upstream end 466 of the flared portion 444 have the outer diameter DI such that the outer diameter of the cylindrical portion 442 may be described as being constant along the entire length thereof. The second or downstream end 467 of the flared portion 444 defining the outflow end 468 of the inner frame 440 has an outer diameter D2 that is greater than the outer diameter DI. Thus, the flared portion 444 flares radially, outwardly from the first end 466 having the outer diameter DI to the second end 467 having the outer diameter D2 such that the flared portion 444 has a generally frustoconical shape or profile. The outer diameter D2 of the outflow end 468 of the inner frame 440 is substantially similar to the outer diameter D3 of the outflow end 438 of the outer frame 420, as the outflow end 468 of the inner frame 440 abuts against an inner surface of the outer frame 420 at the outflow end 438 thereof and is attached to the outflow end 438 of the outer frame 420 as described in more detail below.

[0219] The inner frame 440 includes a plurality of openings 446. In an embodiment, the inner frame 440 includes exactly three rows of openings 446, namely a first row of openings 446A, a second row of openings 446B, and a third row of openings 446C. The first row of openings 446A is formed at the inflow end 462 of the inner frame 440, the third row of openings 446C is formed at the outflow end 468 of the inner frame 440, and the second row of openings 446B extends between the first and third rows of openings 446A, and 446C, respectively. In an embodiment, the cylindrical portion 442 of the inner frame 440 includes the first row of openings 446A and the flared portion 444 of the inner frame 440 includes the third row of openings 446C, while the second row of openings 446B is within the cylindrical portion 442 and the flared portion 442. More particularly, in an embodiment, the two adjacent endmost struts 450 of the second row of openings 446B closest to the outflow end 468 are within the flared portion 444 of the inner frame.

[0220] In an embodiment, all openings 446 of the first row of openings 446A and the second row of openings 446B are substantially the same size and shape. The openings 446 of the first row of openings 446A and the second row of openings 446B are formed with a shape pattern distinct from a shape pattern of the openings of the third row of openings 446C, as illustrated in FIGS. 2D-2F. In an embodiment, each opening 446 of the first row of openings 446A and thesecond row of openings 446B is formed in a hexagonal shape and each opening 446 of the third row of openings 446C is formed in a palmate webbed-foot shape.

[0221] FIG. 4G illustrates an enlarged side view of a single opening of the first or second row of openings 446A, 446B. As shown in FIG. 4G, each opening 446 of the first row of openings 446A and / or the second row of openings 446B is formed by six struts 450 with each pair of struts 450 having a crown 452 therebetween. Two opposing struts 450 are substantially parallel to each other, and a first pair of angled struts 450 extend proximally from the first or inflow ends of the two opposing parallel struts 450 and are angled inwardly towards each other while a second pair of angled struts 450 extend distally from the second or outflow ends of the two opposing parallel struts 450 and are angled inwardly towards each other. In an embodiment, the inner frame 440 has a total of twelve endmost crowns 452 at the inflow end 462 of the inner frame 440. Stated another way, the proximal-most crowns of the first row of openings 446A form the endmost inflow crowns of the inner frame 440.

[0222] The outflow end 468 of the inner frame 440 includes a plurality of radially- extending segments 480 and an outflow ring 486 formed of a plurality of struts 488 and a plurality of crowns 489, with each crown 489 being formed between a pair of opposing struts 488. Each crown 489 is a curved segment or bend extending between opposing struts 488. The plurality of radially -extending segments 480 extends between endmost outflow crowns 452 of the second row of openings 446B and endmost outflow crowns 489 of the outflow ring 486. More particularly, each radially -extending segment 480 includes a first or inflow end 482 and a second or outflow end 484. The first or inflow end 482 of each radially-extending segment 480 is coextensive or integrally formed with an endmost outflow crown of the openings of the second row of openings 446B, and the second or outflow end 484 of each radially extending segment 480 is coextensive or integrally formed with an endmost outflow crown 489 of the outflow ring 486. Similar to the cylindrical portion 442 of the inner frame 440, the outflow ring 486 is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 400. The radially- extending segments 480, along with the two adjacent endmost struts 450 of the second row of openings 446B closest to the outflow end 468, do not extend parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 400 but rather flares radially outward.

[0223] FIG. 4H is an enlarged side view of a single opening of the third row of openings 446C. As shown in FIG. 4H, each opening 446 of the third row of openings 446C is formed in ashape that may be generally described as a palmate webbed-foot shape. More particularly, each opening 446 of the third row of openings 446C is formed via four adjacent struts 488 of the outflow ring 486, two adjacent endmost struts 450 of the second row of openings 446B closest to the outflow end 468, and two adjacent radially-extending segments 480. In an embodiment, the inner frame 440 has a total of twelve endmost crowns at the outflow end 468 of the inner frame 440 which are formed by the endmost or distal-most outflow crowns 489 of the outflow ring 486. In an embodiment, every endmost crown 452B at the outflow end 468 of the inner frame 440 includes an eyelet 459 formed thereon or attached thereto which is configured for attachment to the outer frame 420 as will be described in more detail herein.

[0224] The outer frame 420 and the inner frame 440 are attached to each other at respective outflow ends 438, 468 thereof. More particularly, the second or outflow end 438 of the cylindrical fixation region 422 of the outer frame 420 is attached to the outflow end 468 of the inner frame 440. In the embodiment shown, the inner frame 440 includes a plurality of eyelets 459 formed integrally with the endmost or distal-most outflow crowns 489 of the outflow ring 486 and the outer frame 420 includes a plurality of 468 formed integrally with the endmost or distal-most outflow crowns 432 of the cylindrical fixation region 422 of the outer frame 420. Respective eyelets 439, 459 of the outer frame 420 and the inner frame 440 are aligned and attached via rivets (not shown) to form a plurality of connection points 470 between the outer frame 420 and the inner frame 440 together. However, in other embodiments, threads, adhesives, solder, laser welding, metal bolts or other mechanical features, or other types of fasteners can be used to secure the inner frame 440 to the outer frame 420.

[0225] In an embodiment, the outer frame 420 and the inner frame 440 are attached to each other at exactly twelve connection points 470. In an embodiment, a ratio of the endmost outflow crowns 432 of the outer frame 420 to the endmost outflow crowns 489 of the inner frame 440 is 2:1. More particularly, every other crown 432, or alternating crowns 432, at the outflow end 438 of the outer frame 420 is configured to connect or be attached to a crown 489 at the outflow end 468 of the inner frame 440 via respective eyelets 439, 459 which are further sutured, riveted, glued, bonded, mechanically interlocked, or otherwise fastened to each other. By having these connection points 470 at the outflow ends 438, 468 of the outer and inner frames 420, 440, respectively, the geometry of the flared portion 444 of the inner frame 440, and the geometry of the outer frame 420 allow for increased stent structure durability, i.e. greater capabilities in dealing with high stressor high load applied against the transcatheter heart valve prosthesis 400 without succumbing to breakage, deformation, or overall deterioration of the integrity of the dual frame stent structure 410, that otherwise may result from loading the transcatheter heart valve prosthesis 400 into a delivery system (not shown), deploying the transcatheter heart valve prosthesis 400 from said delivery system, or from continual forces applied to the transcatheter heart valve prosthesis 400 while implanted within the patient’s heart.

[0226] With reference to FIG. 4 A and 4B, when the dual frame stent structure 410 is in its radially expanded configuration, the first or inflow end 436 of the cylindrical fixation region 422 of the outer frame 420 is radially spaced from the inner frame 440. As such, forces from the native anatomy during operation of the native valve after the transcatheter heart valve prosthesis 400 has been implanted are primarily absorbed by the outer frame 420 such that the inner frame 440 and the prosthetic valve 406 coupled thereto remain substantially undeformed. In other words, the inner frame 440 and prosthetic valve 406 are effectively mechanically isolated from the distorting forces exerted on the outer frame 420 by the native tissue, e.g., radially compressive forces exerted by the native annulus and / or leaflets, longitudinal diastolic and systolic forces, hoop stress, etc.

[0227] As best illustrated in FIG. 4A, the cylindrical fixation region 422 of the outer frame 420 has a first length or height Hl from the first end 436 to the second end 438 thereof, and the inner frame 440 has a second length or height H2 from the inflow end 462 to the outflow end 468 thereof. In an embodiment, the second height H2 is between 0 % and 250 % longer than the first height Hl. In an embodiment, the height Hl of the outer frame 420 is relative to the height H2 of the inner frame 440 at a ratio of 1.0 : 2.5. Stated another way, the inner frame 440 may be up to 2.5 times taller than the outer frame 420, with the inner frame 440 being 2.5 times taller as the maximum condition and the inner frame 440 being the same size as the outer frame 420 being the minimum condition. Generally, the height Hl of the outer frame 420 is less than that of conventional transcatheter heart valve prostheses having dual frames configured for placement in a native mitral valve known to those having ordinary skill in the art. By shortening the height Hl of the outer frame 420, protrusion of the outer frame 420 into a ventricle of a native atrioventricular valve is prevented, and thus improving the uninterrupted flow of fluid through the transcatheter heart valve prosthesis 400 as shown and described herein.

[0228] FIGS. 5A-5A depict a transcatheter heart valve prosthesis 500 including a dual frame stent structure 510 according to a fourth embodiment hereof. Similar to the dual frame stentstructure 210, the dual frame stent structure 510 includes an inner frame 540 and an outer frame 520. The dual frame stent structure 510 is intended to form the scaffolding of a transcatheter heart valve prosthesis 500 having a prosthetic valve component (such as the prosthetic valve component 206) disposed within the inner frame 540. The dual frame stent structure 510 may also include one or more sealing members or skirts coupled to the inner and / or outer surfaces of the inner frame 540 and the outer frame 520, as similarly described with respect to the first and second skirts 208, 209 of the transcatheter heart valve prosthesis 200. The prosthetic valve component and skirts are not shown on FIGS. 5A-5B for sake of clarity, to better illustrate the configuration of the dual frame stent structure 510. The transcatheter heart valve prosthesis 500 is configured such that an inflow end 502 of the transcatheter heart valve prosthesis 500 is disposed within and floats freely within a patient’s atrium A and an outflow end 504 of the transcatheter heart valve prosthesis 500 does not extend or only minimally extends into the patient’s left ventricle LV of the heart to avoid obstruction of the left ventricular outflow tract (LVOT).

[0229] Similar to the dual frame stent structure 210, both the inner frame 540 and the outer frame 520 are self-expanding to return to a radially expanded state from a radially compressed state and may be made from materials such as, but not limited to stainless steel, a pseudo-elastic metal such as a nickel titanium alloy (e.g. NITINOL), or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal. The outer frame 520 of the dual frame stent structure 510 circumferentially surrounds at least a portion of the inner frame 540. The inner frame 540 includes a cylindrical portion 542 and a flared portion 544 extending distally and radially outward from a distal or downstream end of the cylindrical portion 542. The inner frame 540 of the dual frame stent structure 510 is the same as the inner frame 340 of the dual frame stent structure 310, and as such the details of the inner frame 540 need not be repeated herein for sake of brevity. Further, in another embodiment hereof, the inner frame 540 may alternatively be the same as the inner frame 240 of the dual frame stent structure 210 or the inner frame 440 of the dual frame stent structure 410. Further, in yet another embodiment, the inner frame 540 may have a different configuration or pattern of openings from the inner frames described herein.

[0230] In this embodiment, a fixation region 522 of the outer frame 520 includes a cylindrical portion 521 and a tapered portion 523 extending distally and radially inward from a distal or downstream end of the cylindrical portion 521. The tapered portion 523 of the outer frame 520 may optimize deployment dynamics when deploying the transcatheter heart valve prosthesis500 from a delivery system into the atrium. The tapered portion 523 of the outer frame 520 may further optimize the structural integrity and durability of the dual frame stent structure 510 by allowing flexion between the outer frame 520 and inner frame 540 when subj ected to forces created by events such as loading into a delivery system (not shown), deployment into the heart, and / or the flow of fluids therethrough.

[0231] The cylindrical portion 521 has a cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 500. The cylindrical portion 521 has a first or upstream end 590 of the cylindrical portion 521 defining an inflow end of the fixation region 522 of the outer frame 520. The first or upstream end 590 of the cylindrical portion 521 has an outer diameter D4. A second or downstream end 592 of cylindrical portion 521 of the outer frame 520 is integrally formed with or coextensive with a first or upstream end 594 of the tapered portion 523 of the outer frame 520, and a second or downstream end 596 of the tapered portion 523 defines an outflow end of the outer frame 520. In an embodiment, the second or downstream end 592 of cylindrical portion 521 and the coextensive first or upstream end 594 of the tapered portion 523 have the outer diameter D4 such that the outer diameter of the cylindrical portion 521 may be described as being constant along the entire length thereof. The second or downstream end 596 of the tapered portion 523 defining the outflow end of the outer frame 520 has an outer diameter D3 that is less than the outer diameter D4. Thus, the tapered portion 523 tapers radially inwardly from the first end 594 having the outer diameter D4 to the second end 596 having the outer diameter D3 such that the tapered portion 523 has a generally frustoconical shape or profile. The outer diameter D3 of the second or downstream end 596 of the tapered portion 523 is substantially similar to the outer diameter of the outflow end of the inner frame 540, as the outflow end of the inner frame 540 abuts against an inner surface of the outer frame 520 at the outflow end thereof and is attached to the outflow end of the outer frame 520 similar to previous embodiments hereof.

[0232] The fixation region 522 is configured to securely fix the outer frame 520 to engage heart tissue at or below an annulus of a native heart valve, such as an annulus of a native mitral valve. The fixation region 522 may be configured to engage subannular tissue, such as inwardfacing surfaces of the native valve leaflets. The fixation region 522 functions as an anchor for the transcatheter heart valve prosthesis 500 to secure its deployed position within a native annulus. In an aspect of the disclosure, the fixation region 522 includes one or more rows of cleats or prongs526 that extend upstream or upward (towards the inflow end 502) and / or radially outward from an outer wall or surface of the fixation region 522 to engage heart tissue. The cleats 526 may be configured to penetrate the native tissue to facilitate retention or maintain position of the transcatheter heart valve prosthesis 500 in a desired implanted location. In another aspect of the disclosure, as an alternative to a cleat structure, the fixation region 522 may employ barbs, spikes, or other tissue fixation mechanisms for engaging heart tissue. As shown in FIG. 5A-5B, in an embodiment, the outer frame 520 includes a total of two rows of cleats 526. In another embodiment hereof, the outer frame 520 may include a single row of cleats 526.

[0233] The fixation region 522 of the outer frame 520 includes a plurality of openings 528 that are formed by a plurality of struts 530 and a plurality of crowns 532, with each crown 532 being formed between a pair of opposing struts 530. Each crown 532 is a curved segment or bend extending between opposing struts 530. In an embodiment, the fixation region 522 includes exactly two rows of openings 528, namely a first row of openings 528A and a second row of openings 528B. In an embodiment, the cylindrical portion 521 of the outer frame 520 includes the first row of openings 528A, while the second row of openings 528B is within the cylindrical portion 521 and the tapered portion 523. More particularly, in an embodiment, the two adjacent endmost struts 530 of the first row of openings 528A closest to the inflow end of the fixation region 522 of the outer frame 520 are within the cylindrical portion 521 of the outer frame 520 and the two adjacent endmost struts 530 of the first row of openings 528A closest to the outflow end of the fixation region 522 of the outer frame 520 are within the tapered portion 523 of the outer frame 520.

[0234] In an embodiment, the first row of openings 528A includes exactly twice (or two times) the number of openings 528 as the second row of openings 528B. In an embodiment, all openings 528 of the first row of openings 528A and the second row of openings 528B are substantially the same size and shape. In an embodiment, all openings 528 of the first row of openings 528A and the second row of openings 528B are substantially diamond-shaped or spadeshaped. In an embodiment, each opening 528 of the outer frame 520 is formed via by four struts 530 with each pair of struts 530 having a crown 532 therebetween. A first pair of angled struts 530 extend distally from each other and are angled outwardly away each other while a second pair of angled struts 530 extend distally from the second or outflow ends of the first pair of angled struts and are angled inwardly towards each other. In an embodiment, the outer frame 520 has a total of twenty-four endmost crowns 532 at each of the inflow end 536 and the outflow end 538 of theouter frame. Stated another way, the proximal-most crowns of the first row of openings 528 A form the endmost inflow crowns of the outer frame 520 and the distal-most crowns of the second row of openings 528B form the endmost outflow crowns of the outer frame 520. In an embodiment, every other endmost crown 532, or alternating crowns 532, at the outflow end 538 of the outer frame 520 includes an eyelet 539 formed thereon or attached thereto which is configured for attachment to the inner frame 540 as in previous embodiments hereof.

[0235] Similar to the previous embodiments hereof, the outer frame 520 and the inner frame 540 are attached to each other at respective outflow ends thereof. In an embodiment, the outer frame 520 and the inner frame 540 are attached to each other at exactly twelve connection points 570. In an embodiment, a ratio of the endmost outflow crowns 532 of the outer frame 520 to the endmost outflow crowns of the inner frame 540 is 2: 1. More particularly, every other crown 532, or alternating crowns 532, at the outflow end of the outer frame 520 is configured to connect or be attached to a crown at the outflow end of the inner frame 540 via respective eyelets which are further sutured, riveted, glued, bonded, mechanically interlocked, or otherwise fastened to each other.

[0236] With reference to FIG. 5 A and 5B, when the dual frame stent structure 510 is in its radially expanded configuration, the first or upstream end 590 of the cylindrical portion 521 of the outer frame 520 is radially spaced from the inner frame 540. As such, forces from the native anatomy during operation of the native valve after the transcatheter heart valve prosthesis 500 has been implanted are primarily absorbed by the outer frame 520 such that the inner frame 540 and the prosthetic valve coupled thereto remain substantially undeformed. In other words, the inner frame 540 and prosthetic valve are effectively mechanically isolated from the distorting forces exerted on the outer frame 520 by the native tissue, e.g., radially compressive forces exerted by the native annulus and / or leaflets, longitudinal diastolic and systolic forces, hoop stress, etc.

[0237] As best illustrated in FIG. 5A, the fixation region 522 of the outer frame 520 has a first length or height Hl from the first or upstream end 590 of the cylindrical portion 521 to the second or downstream end 56 of the tapered portion 523 thereof, and the inner frame 540 has a second length or height H2 from the inflow end to the outflow end thereof. In an embodiment, the second height H2 is between 0 % and 250 % longer than the first height Hl. In an embodiment, the height Hl of the outer frame 520 is relative to the height H2 of the inner frame 540 at a ratio of 1.0 : 2.5. Stated another way, the inner frame 540 may be up to 2.5 times taller than the outerframe 520, with the inner frame 540 being 2.5 times taller as the maximum condition and the inner frame 540 being the same size as the outer frame 520 being the minimum condition. Generally, the height Hl of the outer frame 520 is less than that of conventional transcatheter heart valve prostheses having dual frames configured for placement in a native mitral valve known to those having ordinary skill in the art. By shortening the height Hl of the outer frame 520, protrusion of the outer frame 520 into a ventricle of a native atrioventricular valve is prevented, and thus improving the uninterrupted flow of fluid through the transcatheter heart valve prosthesis 500 as shown and described herein.

[0238] FIGS. 6A-6B depict a transcatheter heart valve prosthesis 600 including a dual frame stent structure 610 according to a fifth embodiment hereof. The dual frame stent structure 610 is the same as the dual frame stent structure 510, except that an outer frame 620 of the dual frame stent structure 610 includes a proximal extension 698 of a fixation region 622 at the inflow end thereof to improve sealing and migration resistance of the transcatheter prosthesis. The proximal extension 698 includes an additional partial row of cells or openings 628C that are formed integrally with a fixation region 622 of the outer frame 620, as well as an additional partial row of cleats 626C extending from the additional partial row of openings 628C. The additional partial row of openings 628C does not extend around the entire circumference of the inflow end of the outer frame 620. More particularly, the additional partial row of openings 628C extends around between 50° and 70° of the circumference of the inflow end of the outer frame 620. In an embodiment, the additional partial row of openings 628C is configured to be positioned adjacent to the anterior leaflet of a native mitral valve and therefore the outer frame 620 includes additional surface area for posterior wall fixation or sealing. As a result, the additional partial row of cells openings 628C is configured to improve sealing and migration resistance of the outer frame 620. The outer frame 620 thus may be considered to include an asymmetric design, such that a first side 620A of the outer frame 620 comprises a height H1A less than a height H1B of a second side 620B of the outer frame 620.

[0239] FIG. 7 is a side view of an embodiment of the dual frame stent structure 210 of FIGS. 2A-2I including a brim 724 radially extending from a proximal or inflow end of the fixation region 222 of the outer frame 220. Although the brim 724 is depicted on the first embodiment of the dual frame stent structure 210, it will be understood by those of ordinary skill in the art that the brim may be similarly incorporated into the dual frame stent structure 310 of the secondembodiment, the dual frame stent structure 410 of the third embodiment, the dual frame stent structure 510 of the fourth embodiment, or the dual frame stent structure 610 of the fifth embodiment. As shown in FIG. 7, the brim 724 extends radially outwardly and upwardly (towards the inflow end of the transcatheter valve prosthesis). In an embodiment, the brim 724 may include overlapping, 180 degree out of phase sinusoidal wire forms that are attached and hinged to the outer frame 220 by a suitable biocompatible low-profile fabric used in bioprosthetic implants namely endovascular grafts, heart valves or left atrial appendage devices to promote biointegration, such as woven polyethylene terephthalate (PET) fabric. The brim 724 serves to locate the transcatheter heart valve prosthesis in the native heart valve. In particular, once the brim 724 is radially expanded in the native heart valve (i.e., upon “flowering” of the brim), the brim 724 is aligned with the upstream surface of the annulus of the native heart valve. Upon alignment of the brim 724 with the upstream surface of the annulus, proper placement of the transcatheter heart valve prosthesis has been achieved, and the transcatheter heart valve prosthesis may be fully deployed and released into the native anatomy. The brim 724 may also function as an atrial retainer, if present, and to serve such a function the brim 724 may be configured to engage tissue above the native annulus AN, such as a supra-annular surface or some other tissue in the left atrium, to thereby inhibit downstream migration of a prosthetic heart valve, for e.g., during atrial systole. Further details for a suitable brim structure having two sinusoidal rings and a sealing component may be found in U.S. Pat. No. 11,318,013, titled “COMPACT PROSTHETIC HEART VALVE DEVICE” and assigned to the same assignee of the present invention, the disclosure of which is incorporated by reference herein in its entirety.

[0240] FIGS. 8A-8F depict a dual frame stent structure 810 according to a sixth embodiment hereof. The dual frame stent structure 810 comprises an inner frame 840 and an outer frame 820 which circumferentially surrounds at least a portion of the inner frame 840. Unlike the previous embodiments, the inner frame 840 is substantially or predominantly cylindrical and the outer frame 820 includes a plurality of connector struts or intercell fixation struts 850 that connect the outer frame 820 to the inner frame 840. As shown in FIGS. 8A-8C, each intercell fixation strut 850 of the plurality of intercell fixation struts 850 extends radially inward from an inflow end 836 of the outer frame 820 and are attached to an outflow end 868 of the inner frame 840.

[0241] The dual frame stent structure 810 is intended to form the scaffolding of a transcatheter heart valve prosthesis 800 having a prosthetic valve component (such as theprosthetic valve component 206) disposed within the inner frame 840. The dual frame stent structure 810 may also include one or more sealing members or skirts coupled to the inner and / or outer surfaces of the inner frame 840 and the outer frame 820, as similarly described with respect to the first and second skirts 208, 209 of the transcatheter heart valve prosthesis 200. The prosthetic valve component and skirts are not shown on FIGS. 8A-8F for sake of clarity, to better illustrate the configuration of the dual frame stent structure 810. The transcatheter heart valve prosthesis 800 is configured to have a profile such that an inflow end of the transcatheter heart valve prosthesis 800 is disposed within and floats freely within a patient’s atrium A and an outflow end of the transcatheter heart valve prosthesis 800 does not extend or only minimally extends into the patient’s left ventricle LV of the heart to avoid obstruction of the left ventricular outflow tract (LVOT).

[0242] Similar to the dual frame stent structure 210, both the inner frame 840 and the outer frame 820 are self-expanding to return to a radially expanded state from a radially compressed state and may be made from materials such as, but not limited to stainless steel, a pseudo-elastic metal such as a nickel titanium alloy (e.g. NITINOL), or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal.

[0243] The outer frame 820 of the dual frame stent structure 810 circumferentially surrounds at least a portion of the inner frame 840. The outer frame 820 includes a cylindrical fixation region 822 having the first or inflow end 836 and a second or outflow end 838. The outer frame 820 may optionally include a flange or brim (not shown) extending radially outward from a proximal or upstream end of the fixation region 822 of the outer frame 820, as described in more detail herein with respect to FIG. 7. The cylindrical fixation region 822 has a cylindrical shape which is oriented to extend generally parallel to a longitudinal axis LA of the dual frame stent structure 810. The cylindrical fixation region 822 has an outer diameter that is constant from the inflow end 836 to the outflow end 838, which defines the outflow end of the outer frame 220. The cylindrical fixation region 822 is configured to securely fix the outer frame 820 to engage heart tissue at or below an annulus of a native heart valve, such as an annulus of a native mitral valve. The cylindrical fixation region 822 may be configured to engage subannular tissue, such as inwardfacing surfaces of the native valve leaflets. The cylindrical fixation region 822 functions as an anchor for the dual frame stent structure 810 to secure its deployed position within a native annulus.

[0244] In an aspect of the disclosure, the cylindrical fixation region 822 includes one or more rows of cleats or prongs 826 that extend upstream or upward (towards the inflow end 836 of the cylindrical fixation region 822) and / or radially outward from an outer wall or surface of the cylindrical fixation region 822 to engage heart tissue. The cleats 826 may be configured to penetrate the native tissue to facilitate retention or maintain position of the dual frame stent structure 810 in a desired implanted location. In another aspect of the disclosure, as an alternative to a cleat structure, the cylindrical fixation region 822 may employ barbs, spikes, or other tissue fixation mechanisms for engaging heart tissue. As shown in FIGS. 8A and 8B, in an embodiment, the outer frame 820 includes a total of two rows of cleats 826. More particularly, a first row of cleats 826A is disposed near or adjacent to the inflow end 836 of the cylindrical fixation region 822 and a second row of cleats 826B is disposed at or on the outflow end 838 of the cylindrical fixation region 822. In another embodiment hereof, the outer frame 820 may include a single row of cleats 826.

[0245] The cylindrical fixation region 822 of the outer frame 820 includes a plurality of openings 828 that are formed by a plurality of struts 830 and a plurality of crowns 832, with each crown 832 being formed between a pair of opposing struts 830. Each crown 832 is a curved segment or bend extending between opposing struts 830. In an embodiment, the outer frame 820 has a total of twenty -four endmost crowns 832 at each of the inflow end 836 and the outflow end 838 of the cylindrical fixation region 822.

[0246] The outer frame 820, in an expanded state, comprises a first row of openings 828A, a second row of openings 828B, and a third row of openings 828C. In an embodiment, the first row of openings 828A in the outer frame 820 comprises relatively large openings that extend from the inflow end 836 of the cylindrical fixation region 822 to the outflow end 838 of the cylindrical fixation region 822, and comprising a first shape. The second and third row of openings 828B, 828C in the outer frame 820 comprises relatively small openings comprising a second shape, and each opening of the second and third row of openings 828B, 828C in the outer frame 820 is relatively smaller than each opening of first row of openings 828A in the outer frame 820. In an embodiment, all openings of the first, second, and third rows of openings 828A, 828B, 828C are substantially the same shape. In an embodiment, all openings of the first, second, and third rows of openings 828A, 828B, 828C are substantially diamond-shaped. Each opening of the first row of openings 828A may be in the range of 300% to 700% larger than each opening of the secondand third rows of openings 828B, 828C. The relatively large openings of the first row of openings 828A provide a larger area for native tissue to protrude or grow into the outer frame 820. Enhanced interaction and in-growth of the native tissue into the large openings provides another means to enhance migration resistance.

[0247] The second and third rows of openings 828B, 828C are axially aligned and collectively extend from the inflow end 836 of the cylindrical fixation region 822 to the outflow end 838 of the cylindrical fixation region 822. Each opening 828B of the second row of openings 828B is disposed directly adjacent to an opening of the first row of openings 828A, such that an opening 828A of the first row of openings 828A is disposed between a pair of openings 828B of the second row of openings 828B. Thus, the openings 828B of the second row of openings 828B may be considered non-continuous since the openings 828B are not disposed directly adjacent to each other but rather are disposed in an alternating fashion relative to the first row of openings 828A. Similarly, each opening 828C of the third row of openings 828C is disposed directly adjacent to an opening of the first row of openings 828 A, such that an opening 828 A of the first row of openings 828 A is disposed between a pair of openings 828C of the third row of openings 828C. Thus, the openings 828C of the third row of openings 828C may be considered non- continuous since the openings 828C are not disposed directly adjacent to each other but rather are disposed in an alternating fashion relative to the first row of openings 828A.

[0248] As best shown on FIG. 8D, which is a schematic view of the outer frame 820 laid flat as-formed or cut for illustrative purposes only, the plurality of intercell fixation struts 850 are integrally formed with the outer frame 820. The outer frame 820 may be formed by a laser-cut manufacturing method and / or other conventional frame forming methods. For example, the outer frame 820 may be laser cut from a single metal tube into the desired geometry, creating a tubular scaffold of interconnected struts and crowns that form the openings 828 and the plurality of intercell fixation struts 850.

[0249] The inner frame 840 defines a lumen 841 from an inflow end 862 of the inner frame 840 to an outflow end 868 of the inner frame 840. The inflow end 862 of the inner frame 840 defines the inflow end of the dual frame stent structure 810. The prosthetic valve component 206, described in detail above, is disposed within the lumen 841 of the inner frame. The inner frame 840 has a cylindrical shape which is oriented to extend generally parallel to the longitudinal axisLA of the transcatheter heart valve prosthesis 800. An outer diameter of the inner frame 840 does not vary, or is constant, along the entire length thereof.

[0250] The inner frame 840 includes a plurality of openings 846. The plurality of openings 846 in the inner frame 840 are formed by a plurality of struts 854 and a plurality of crowns 852, with each crown 852 being formed between a pair of opposing struts 854. Each crown 852 is a curved segment orbend extending between opposing struts 854. In an embodiment, the inner frame 840 includes exactly two rows of openings 846, namely a first row of openings 846A and a second row of openings 846B. In an embodiment, the first row of openings 846A includes the same number of openings as the second row of openings 846B. In an embodiment, all openings 846 of the first row of openings 846A and the second row of openings 846B are substantially the same size and shape. In an embodiment, each opening 846 of the first row of openings 846A and the second row of openings 846B is formed in a hexagonal shape. In an embodiment, the inner frame 840 has a total of twelve endmost crowns 852 at the inflow end 862 of the inner frame 840. Stated another way, the proximal-most crowns of the first row of openings 846A form the endmost inflow crowns of the inner frame 840. The inner frame 840 has a total of twelve endmost crowns 852 at the outflow end 868 of the inner frame 840. Stated another way, the distal-most crowns of the second row of openings 846B form the endmost outflow crowns of the inner frame 840.

[0251] The outer frame 820 and the inner frame 840 are attached to each other via the plurality of intercell fixation struts 850. More particularly, the plurality of intercell fixation struts 850 form a connection from inflow crowns 832 of the outer frame 820 to the plurality of endmost outflow crowns 852 of the inner frame 840. The outer frame 820 includes a plurality of inflow crowns 832, and the inner frame 840 includes a plurality of endmost outflow crowns 852 and, in an embodiment, a ratio of the inflow crowns 832 of the outer frame 820 to the endmost outflow crowns 852 of the inner frame 840 is 2:1. Since the ratio of the inflow crowns 832 of the outer frame 820 to the endmost outflow crowns 852 of the inner frame 840 is 2: 1, two adjacent intercell fixation struts 850 connect to a single endmost outflow crowns 852 of the inner frame 840 as best depicted in the top view of FIG. 8C.

[0252] As stated above, the plurality of intercell fixation struts 850 are integrally formed with the outer frame 820. Each intercell fixation struts 850 is a substantially straight segment that extends between an inflow crown 832 of the outer frame 820 and an eyelet 839 (best shown on FIG. 8D). More particularly, an eyelet 839 is formed integrally between two adjacent intercellfixation struts 850 as best shown on FIG. 8D. Stated another way, a single eyelet 839 is formed between a pair of intercell fixation struts 850. Each pair of intercell fixation struts 850 having a single eyelet 839 formed therebetween may be considered to form a V-shaped connector having two legs and an apex therebetween, with the pair of intercell fixation struts 850 forming the legs of the V-shaped connector and the single eyelet 839 forming the apex of the V-shaped connector.

[0253] In the embodiment shown, the inner frame 840 includes a plurality of eyelets 859 formed integrally with the endmost or distal-most outflow crowns 852. Respective eyelets 839, 859 of the outer frame 820 and the inner frame 840 are aligned and attached via rivets (not shown) to formed a plurality of connection points between the outer frame 820 and the inner frame 840 together. However, in other embodiments, threads, adhesives, solder, laser welding, metal bolts or other mechanical features, or other types of fasteners can be used to secure the inner frame 840 to the outer frame 820. In an embodiment, the outer frame 820 and the inner frame 840 are attached to each other at exactly twelve connection points.

[0254] The intercell fixation struts 850 of the present embodiment provide a number of advantages. Use of the intercell fixation struts 850 eliminates the need for a flared portion of the inner frame and / or the outer frame. Therefore, the overall height of the inner frame, the outer frame, or both, may be shortened as a result of the elimination of the flared portions, resulting in reducing risk of left ventricular outflow tract obstruction (LVOTO). Additionally, the intercell fixation struts 850 exert an outward radial force when under an axial load. More particularly, axial forces directed towards the inflow direction, resulting from mitral valve backflow, cause the intercell fixation struts 850 to exert outward radial forces. The increased radial forces resist migration of the prosthesis.

[0255] With reference to FIG. 8A-8C, when the dual frame stent structure 810 is in its radially expanded configuration, the cylindrical fixation region 822 of the outer frame 820 is radially spaced from the inner frame 840. As such, forces from the native anatomy during operation of the native valve after the transcatheter heart valve prosthesis has been implanted are primarily absorbed by the outer frame 820 such that the inner frame 840 and the prosthetic valve component 206 coupled thereto remain substantially undeformed. In other words, the inner frame 840 and prosthetic valve component 206 are effectively mechanically isolated from the distorting forces exerted on the outer frame 820 by the native tissue, e.g., radially compressive forces exerted by the native annulus and / or leaflets, longitudinal diastolic and systolic forces, hoop stress, etc.

[0256] As best illustrated in FIG. 8A, the cylindrical fixation region 822 of the outer frame 820 has a first length or height Hl from the first end 836 to the second end 838 thereof, and the inner frame 840 has a second length or height H2 from the inflow end 862 to the outflow end 868 thereof. In an embodiment, the second height H2 is between 0 % and 250 % longer than the first height Hl. In an embodiment, the height Hl of the outer frame 820 is relative to the height H2 of the inner frame 840 at a ratio of 1.0 : 2.5. Stated another way, the inner frame 840 may be up to 2.5 times taller than the outer frame 820, with the inner frame 840 being 2.5 times taller as the maximum condition and the inner frame 840 being the same size as the outer frame 820 being the minimum condition. In an embodiment, the height Hl of the outer frame 820 may be between 5mm - 35mm, and the height H2 of the inner frame 840 may be between 15mm - 100mm. Generally, the height Hl of the outer frame 820 is less than that of conventional transcatheter heart valve prostheses having dual frames configured for placement in a native mitral valve known to those having ordinary skill in the art. By shortening the height Hl of the outer frame 820, protrusion of the outer frame 820 into a ventricle of a native atrioventricular valve is prevented, and thus improving the uninterrupted flow of fluid through the transcatheter heart valve prosthesis as shown and described herein.

[0257] FIG. 9 depicts a transcatheter heart valve prosthesis 900 including a dual frame stent structure 910 according to a seventh embodiment hereof. The dual frame stent structure 910 is the same as the dual frame stent structure 810, except that an outer frame 920 of the dual frame stent structure 910 includes a flared outflow portion 923 to improve sealing and migration resistance of the transcatheter prosthesis. More particularly, the outer frame 920 includes a cylindrical portion 922 and the flared outflow portion 923. The cylindrical portion 922 has a cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 900. The cylindrical portion 922 has a first or upstream end 936 of the cylindrical portion 922 defining the inflow end of the outer frame 920. The first or upstream end 936 of the cylindrical portion 922 has an outer diameterDl. A second or downstream end 937A is integrally formed with or coextensive with a first or upstream end 937B of the flared portion 923 of the outer frame 920, and a second or downstream end 938 of the flared portion 923 defines the outflow end of the outer frame 920. In an embodiment, the second or downstream end 937A of the cylindrical portion 922 and the coextensive first or upstream end 937B of the flared portion 923 have the outer diameter DI such that the outer diameter of the cylindrical portion 922may be described as being constant along the entire length thereof. The second or downstream end 938 of the flared portion 923 has an outer diameter D2 that is greater than the outer diameter DI . Thus, the flared portion 923 flares radially, outwardly from the first end 937B having the outer diameter DI to the second end 938 having the outer diameter D2 such that the flared portion 923 has a generally frustoconical shape or profile. The flared portion 923 of the outer frame 920 contributes to resisting migration of the prosthesis 900, because the increased diameter at the outflow end 938 increases the interaction between the prosthetic valve and the annulus.

[0258] An outer frame comprising a flared portion as discussed regarding the seventh embodiment may be combined with any of the embodiment of the transcatheter heart valve prosthesis discussed herein. Embodiments including both a flared portion of the outer frame, as discussed regarding the seventh embodiment, and intercell fixation struts, as discussed regarding the sixth embodiment, will have even greater increased migration resistance due the ability of each feature to resist migration as a result of axial forces directed towards the inflow direction.

[0259] The intercell fixation struts 850 may be utilized in dual frame stent structures having alternative cell or opening patterns or configurations. For example, FIG. 10 depicts a transcatheter heart valve prosthesis 1000 including a dual frame stent structure 1010 according to an eighth embodiment hereof. The dual frame stent structure 1010 is the same as the dual frame stent structure 810, except that an outer frame 1020 of the dual frame stent structure 1010 has a different pattern of cells or openings. Particularly, the outer frame 1020 has the same pattern of cells or openings as the outer frame 220 described above with respect to the embodiment of FIG. 2A. Although shown with the outer frame configuration of FIG. 2A, it will be understood by those of ordinary skill in the art that the intercell fixation struts may be used with any of the outer frame designs of other embodiments described herein, as well as alternative outer frame designs. Similarly, the cell or opening pattern of the inner frame may vary from the particular configuration described herein.

[0260] FIGS. 11A-11D depicts a dual frame stent structure 1110 according to a ninth embodiment hereof. The dual frame stent structure 1110 comprises an inner frame 1140 and an outer frame 1120 which circumferentially surrounds at least a portion of the inner frame 1140. Unlike the previous embodiments, the inner frame 1140 and the outer frame 1120 are each integrally formed with a plurality of connecting members that form connecting bridges between cylindrical portions of the outer frame 1120 and the inner frame 1140. As shown in FIG. 11 A, aplurality of first connecting members 1124 of the outer frame 1 120 are attached to a plurality of second connecting members 1144 of the inner frame 1140 to form the connecting bridges.

[0261] The dual frame stent structure 1110 is intended to form the scaffolding of a transcatheter heart valve prosthesis 1100 having a prosthetic valve component (such as the prosthetic valve component 206) disposed within the inner frame 1140. The dual frame stent structure 1110 may also include one or more sealing members or skirts coupled to the inner and / or outer surfaces of the inner frame 1140 and the outer frame 1120, as similarly described with respect to the first and second skirts 208, 209 of the transcatheter heart valve prosthesis 200. The prosthetic valve component and skirts are not shown on FIGS. 11 A-l ID for sake of clarity, to better illustrate the configuration of the dual frame stent structure 1110. The transcatheter heart valve prosthesis 1100 is configured to have a profile such that an inflow end of the transcatheter heart valve prosthesis 1100 is disposed within and floats freely within a patient’s atrium A and an outflow end of the transcatheter heart valve prosthesis 1100 does not extend or only minimally extends into the patient’s left ventricle LV of the heart to avoid obstruction of the left ventricular outflow tract (LVOT).

[0262] Similar to the dual frame stent structure 210, both the inner frame 1140 and the outer frame 1120 are self-expanding to return to a radially expanded state from a radially compressed state and may be made from materials such as, but not limited to stainless steel, a pseudo-elastic metal such as a nickel titanium alloy (e.g. NITINOL), or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal.

[0263] The outer frame 1120 of the dual frame stent structure 1110 circumferentially surrounds at least a portion of the inner frame 1140. The outer frame 1120 includes a cylindrical fixation region 1122 having a first or inflow end 1136 and a second or outflow end 1138. The outer frame 1120 may optionally include a flange or brim (not shown) extending radially outward from a proximal or upstream end of the fixation region 1122 of the outer frame 1120, as described in more detail herein with respect to FIG. 7. The cylindrical fixation region 1122 has a cylindrical shape which is oriented to extend generally parallel to a longitudinal axis LA of the dual frame stent structure 1110. The cylindrical fixation region 1122 has an outer diameter that is constant from the inflow end 1136 to the outflow end 1138, which defines the outflow end of the outer frame 1120. The cylindrical fixation region 1122 is configured to securely fix the outer frame 1120 to engage heart tissue at or below an annulus of a native heart valve, such as an annulus of a nativemitral valve. The cylindrical fixation region 1 122 may be configured to engage subannular tissue, such as inward-facing surfaces of the native valve leaflets. The cylindrical fixation region 1122 functions as an anchor for the dual frame stent structure 1110 to secure its deployed position within a native annulus.

[0264] Similar to previous embodiments, the cylindrical fixation region 1122 of the outer frame 1120 includes a plurality of openings 1128 that are formed by a plurality of struts 1130 and a plurality of crowns 1132, with each crown 1132 being formed between a pair of opposing struts 1130. Each crown 1132 is a curved segment or bend extending between opposing struts 1130. In an embodiment, the outer frame 1120 has a total of twenty-four endmost crowns 1132 at each of the inflow end 1136 and the outflow end 1138 of the cylindrical fixation region 1122. In an embodiment, the outer frame 1120 includes exactly two rows of openings 1128, namely a first row of openings 1128A and a second row of openings 1128B. In an embodiment, the first row of openings 1128A includes the same number of openings as the second row of openings 1128B. In an embodiment, all openings 1128 of the first row of openings 1128A and the second row of openings 1128B are substantially the same size and shape. In an embodiment, each opening 1128 of the first row of openings 1128 A and the second row of openings 1128B is formed in a diamond shape. In an embodiment, the outer frame 1120 has a total of twenty-four endmost crowns 1132 at the inflow end 1136 of twenty-four endmost crowns. Stated another way, the proximal-most crowns of the first row of openings 1128 A form the endmost inflow crowns of t the outer frame 1120. The outer frame 1120 has a total of twenty -four endmost crowns 1132 at the outflow end 1138 of the outer frame 1120. Stated another way, the distal-most crowns of the second row of openings 1128B form the endmost outflow crowns of the outer frame 1120. The openings 1128 may take any size and shape as discussed in embodiments herein, such as in FIGS. 2A or 8A, for example. In the depicted embodiment, the outer frame 1120 includes two rows of openings 1128. In another embodiment hereof, the outer frame 1120 includes three rows of openings 1128. In still further embodiments, the outer frame 1120 includes a single row of openings 1128.

[0265] The outer frame 1120 includes the plurality of first connecting members 1124 extending radially inwards from the inflow end 1136 of the cylindrical fixation region 1122 of the outer frame 1120. The plurality of first connecting members 1124 are integrally formed with the outer frame 1120. The outer frame 1120 may be formed by a laser-cut manufacturing method and / or other conventional frame forming methods. For example, the outer frame 1120 may be lasercut from a single metal tube into the desired geometry, creating a tubular scaffold of interconnected struts and crowns that form the openings 1128 and the plurality of first connecting members 1124.

[0266] In an aspect of the disclosure, the cylindrical fixation region 1122 includes one or more rows of cleats or prongs 1126 that extend upstream or upward (towards the inflow end 1136 of the cylindrical fixation region 1122) and / or radially outward from an outer wall or surface of the cylindrical fixation region 1122 to engage heart tissue. The cleats 1126 may be configured to penetrate the native tissue to facilitate retention or maintain position of the dual frame stent structure 1110 in a desired implanted location. In another aspect of the disclosure, as an alternative to a cleat structure, the cylindrical fixation region 1122 may employ barbs, spikes, or other tissue fixation mechanisms for engaging heart tissue. As shown in FIGS. 11 A-l ID, in an embodiment, the outer frame 1120 includes a total of three rows of cleats 1126. In another embodiment hereof, the outer frame 1120 may include two rows of cleats 1126. In still further embodiments, the outer frame 1120 may include a single row of cleats 1126.

[0267] The inner frame 1140 defines a lumen 1141 from an inflow end 1162 of the inner frame 1140 to an outflow end 1168 of the inner frame 1140. The inflow end 1162 of the inner frame 1140 defines the inflow end of the dual frame stent structure 1110. The prosthetic valve component 206, described in detail above, is disposed within the lumen 1141 of the inner frame. The inner frame 1140 has a cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 1100. An outer diameter of the inner frame 1140 may be described as being constant along the entire length thereof.

[0268] The inner frame 1140 includes a plurality of openings 1146. The plurality of openings 1146 in the inner frame 1140 are formed by a plurality of struts 1154 and a plurality of crowns 1152, with each crown 1152 being formed between a pair of opposing struts 1154. Each crown 1152 is a curved segment or bend extending between opposing struts 1154. In an embodiment, the inner frame 1140 includes exactly two rows of openings 1146, namely a first row of openings 1146A and a second row of openings 1146B. In an embodiment, the first row of openings 1146A includes the same number of openings as the second row of openings 1146B. In an embodiment, all openings 1146 of the first row of openings 1146A and the second row of openings 1146B are substantially the same size and shape. In an embodiment, each opening 1146 of the first row of openings 1146 A and the second row of openings 1146B is formed in a hexagonal shape. In an embodiment, the inner frame 1140 has a total of twelve endmost crowns 1152 at theinflow end 1 162 of the inner frame 1140. Stated another way, the proximal-most crowns of the first row of openings 1146A form the endmost inflow crowns of the inner frame 1140. The inner frame 1140 has a total of twelve endmost crowns 1152 at the outflow end 1168 of the inner frame 1140. Stated another way, the distal-most crowns of the second row of openings 1146B form the endmost outflow crowns of the inner frame 1140.

[0269] The inner frame 1140 includes the plurality of second connecting members 1144 extending radially outwards from the inner frame 1140. The plurality of second connecting members 1144 are integrally formed with the inner frame 1140. The inner frame 1140 may be formed by a laser-cut manufacturing method and / or other conventional frame forming methods. For example, the inner frame 1140 may be laser cut from a single metal tube into the desired geometry, creating a tubular scaffold of interconnected struts and crowns that form the openings 1146 and the plurality of second connecting members 1144.

[0270] The outer frame 1120 and the inner frame 1140 are attached to each other via the plurality of first connecting members 1124 and the plurality of second connecting members 1144. More particularly, the plurality of first connecting members 1124 are disposed circumferentially around the cylindrical fixation region 1122 of the outer frame 1120 and extend radially inwards. The plurality of second connecting members 1144 are disposed circumferentially around the inner frame 1140 and extend radially outwards. A free or unattached end of each connecting member 1124 of the plurality of first connecting members 1124 attach to a free of unattached end of each connecting member 1124 of the plurality of second connecting members 1144 to form a plurality of frame connection bridges between the outer frame 1120 and the inner frame 1140. The plurality of frame connection bridges each comprise a respective attachment point 1134 disposed radially in-between the outer frame 1120 and the inner frame 1140. At the attachment points 1134, the plurality of first connecting members 1124 and second connecting members 1144 are attached to each other via rivets (not shown). However, in other embodiments, threads, adhesives, solder, laser welding, metal bolts or other mechanical features, or other types of fasteners can be used to form the attachment points 1134 and thereby secure the inner frame 1140 to the outer frame 1120. In an embodiment, the outer frame 1120 and the inner frame 1140 are attached to each other at exactly twelve attachments points 1134.

[0271] The plurality of first connecting members 1124 and the plurality of second connecting members 1144 are segments that extend from an integral, connected end of therespective inner or outer frame, to a free end. The free end of each connecting member of the plurality of first connecting members 1124 is formed with an eyelet 1139 (see FIG. 11D). Similarly, the free end of each connecting member of the plurality of second connecting members is formed with an eyelet (not shown). The eyelets of each of the plurality of first connecting members 1124 and the eyelets of each of the second connecting members 1144 are configured to be aligned such that they may be attached to each other via rivets (not shown). The segments of the plurality of first connecting members 1124 and the plurality of second connecting members 1144 are substantially straight in the radial direction, as best shown in FIG. 11C, and may be straight or curved in an axial direction. The plurality of first connecting members 1124 and the plurality of second connecting members 1144 are equal to or substantially similar in length such that the connection points 1134 of the frame connection bridges are approximately at a radial midpoint between the outer frame 1120 and the inner frame 1140. When the transcatheter prosthesis 1100 is an expanded configuration, the plurality of first connecting members 1124 and the plurality of second connecting members 1144 maintain an angled orientation such that they each disposed at an angle towards the inflow direction, as shown in FIGS. 11A-B. Accordingly, the frame connection bridges formed by the plurality of first connecting members 1124 and the plurality of second connecting members 1144 maintain an approximate chevron shape, as shown in FIGS. 11A-B. Such an orientation allows the plurality of frame connection bridges to offer enhanced migration resistance in a similar manner to the intercell fixation struts 850 discussed in the sixth embodiment. Axial loads acting on the inner frame 1140 and directed in the inflow direction cause the shared frame connection bridges to flatten and exert a positive radial force. The increased radial forces allow the outer frame 1120 to exert similar force increases on the native heart tissue to resist migration of the prosthesis.

[0272] Although the first connecting members 1124 and the plurality of second connecting members 1144 are shown as single, straight segments or struts, it will be understood by one of ordinary skill in the art that any of the connecting members may have alternative configurations such as but not limited to a “V” or “U” configuration. More particularly, any of the connecting members may include two segments that come together at the attachment point 1134 to form the “V” or “U” configuration having an apex at the attachment point 1134.

[0273] In the ninth embodiment, the plurality of first connecting members 1124 extend from an inflow end 1136 of the outer frame 1120 and the plurality of second connecting members1144 extend from approximately in the middle of the inner frame 1140, as shown in FIGS. 11 A and 11B. FIG. 11D depicts a cut pattern of the outer frame 1120, wherein the plurality of first connecting members are disposed at the inflow end 1136 of the outer frame 1120. As shown in FIG. 11D, the plurality of first connecting members 1124 are disposed alternatingly along the endmost inflow crowns 1132, such that a first connecting member 1124 is disposed at every other endmost inflow crown 1132. FIG. 1 IE depicts a cut pattern of an outer frame 1120E according to an alternative embodiment, wherein the plurality of first connecting members 1124E are disposed adjacent to the inflow end 1136E of the outer frame 1120E. More particularly, the plurality of first connecting members 1124E are disposed alternatingly along the next axial row of inflow crowns 1132E.

[0274] As discussed above, the inner frame 1140 includes twelve crowns 1152 at both the inflow end 1162 and the outflow end 1168 thereof. Further, as discussed above, the outer frame 1120 includes twenty -four crowns 1132 at each of the inflow end 1136 and the outflow end 1138 thereof. As shown in FIG. 11C, the outer frame 1120 includes twelve first connecting members 1124 disposed along alternating crowns 1132 of a given row of crowns 1132 such that the first connecting members 1124 are spaced at equal increments around the circumference of the outer frame 1120. The inner frame 1140 includes twelve second connecting members 1144 disposed along each crown 1152 of a given row of crowns 1152 such that the second connecting members 1144 are spaced at equal increments around the circumference of the inner frame 1140. In further embodiments, the plurality of first connecting members 1124 of the outer frame 1120 may be disposed at any of the rows of crowns 1132. Additionally, the plurality of second connecting members 1144 of the inner frame may be disposed at any of the rows of crowns 1152. In any case, the plurality of first connecting members 1124 and the plurality of second connecting members 1144 are each disposed circumferentially around a single, horizontal row of crowns 1132,1152 such that the outer frame 1120, inner frame 1140, and the plurality of connection bridges are all axially and radially aligned about the longitudinal axis LA.

[0275] Accordingly, a number of arrangements between the outer frame 1120, inner frame 1140, and connection bridges may be achieved. As discussed above, FIGS. 11 A and 1 IB show an embodiment wherein the plurality of connection bridges are disposed at an inflow end 1136 of the outer frame 1120 and near a midpoint of the inner frame 1140. This arrangement results in a portion of the inner frame disposed downstream of the plurality of connection bridges. In someembodiments, a portion of the inner frame 1140 disposed downstream of the connection bridges comprises an uncovered portion which does not receive graft material. More particularly, as best shown in FIG. 1 IB, in this embodiment, the inner frame 1140 includes a sealing member or skirt 1109 coupled to the inner and / or outer surface of the inner frame 1140. The inner skirt 1109 is only coupled to the inflow portion of the inner frame 1140 upstream of the second connecting members 1144, while an uncovered portion 1109B of the inner frame 1140 disposed downstream of the second connecting members 1144 does not have any sealing member or skirt attached thereto. As a result, all or a substantial portion of the second row of openings 1146B or bottom half of the inner frame 1140 are not covered by any type of graft material, i.e., sealing member or skirt, and blood may flow therethrough. An outer skirt 1108 covers a portion of the outer frame 1120 as shown on FIG. 1 IB. The outer skirt 1108 extends over the first connecting members 1124 and the inner skirt 1109 extends over the second connecting members 1144. The inner and outer skirts 1109, 1108 may be attached to each other at the attachment point 1134 between the first and second connecting members 1124, 1144.

[0276] The axial location of the connection bridges relative to the outer frame and the inner frame may be selected in order to achieve various advantages. The axial location of FIGS. 11A- 1 ID primarily reduce LVOTO in addition to resisting migration while other locations, such as the axial location of FIGS. 12A-12B, achieve more of a corking effect in addition to resisting migration. More particularly, FIGS. 12A and 12B show a tenth embodiment which is the same as the ninth embodiment of FIGS. 11A-11D except that the connection bridges are disposed at an outflow end 1238 of an outer frame 1220 and at an outflow end 1268 of an inner frame 1240. In addition, unlike the embodiment of FIGS. 11A-11D, the inner frame 1240 includes a sealing member or skirt 1209 coupled to the inner and / or outer surface of the inner frame 1240 and the inner skirt 1209 is coupled to the full or entire length of the inner frame 1240. FIG. 12B depicts the cut pattern of the outer frame 1220 for this arrangement, wherein a plurality of first connecting members 1224 are disposed at the outflow end 1268 of the outer frame 1220. The plurality of first connecting members 1224 are disposed altematingly along the endmost outflow crowns 1232. This arrangement results in less support at an inflow end 1236 of the outer frame 1220, allowing for a corking effect at the middle and inflow portions of the outer frame 1220. Other arrangements, as discussed above, are envisioned herein and may be selected according to patient anatomy, desired therapeutic effects, and other various factors. For example, in another embodiment (now shown),the plurality of first connecting members extend from the outflow end of the outer frame and the plurality of second connecting members extend from approximately in the middle of the inner frame. In another embodiment (not shown), the plurality of first connecting members extend from approximately the middle of the outer frame and the plurality of second connecting members extend from approximately in the middle of the inner frame. Additionally, to accommodate the first connecting members 1224 in the cut pattern, when the outer frame 1220 is laser cut from a single metal tube into the desired geometry to create a tubular scaffold of interconnected struts and crowns that form the openings and the plurality of first connecting members 1224, the openings at the outflow end of the outer frame 1220 may be larger in height and / or width to accommodate the first connecting members 1224 into the cut pattern compared to the openings proximal to it.

[0277] In this embodiment, as shown on FIG. 12 A, the inner frame 1240 includes a sealing member or skirt 1209 coupled to the inner and / or outer surface of the inner frame 1240. The inner skirt 1209 is coupled to the full length of the inner frame 1240. In addition, an outer skirt 1208 is coupled to the full length of the outer frame 1220. The outer skirt 1208 extends over the first connecting members 1224 and the inner skirt 1209 extends over the second connecting members 1244. The inner and outer skirts 1209, 1208 may be attached to each other at the attachment point between the first and second connecting members 1224, 1244.

[0278] With reference to FIG. 11 A-l ID, when the dual frame stent structure 1110 is in its radially expanded configuration, the cylindrical fixation region 1122 of the outer frame 1120 is radially spaced from the inner frame 1140. As such, forces from the native anatomy during operation of the native valve after the transcatheter heart valve prosthesis has been implanted are primarily absorbed by the outer frame 1120 such that the inner frame 1140 and the prosthetic valve component 206 coupled thereto remain substantially undeformed. In other words, the inner frame 1140 and prosthetic valve component 206 are effectively mechanically isolated from the distorting forces exerted on the outer frame 1120 by the native tissue, e.g., radially compressive forces exerted by the native annulus and / or leaflets, longitudinal diastolic and systolic forces, hoop stress, etc.

[0279] As best illustrated in FIG. 11A, the cylindrical fixation region 1122 of the outer frame 1120 has a first length or height Hl from the first end 1136 to the second end 1138 thereof, and the inner frame 1140 has a second length or height H2 from the inflow end 1162 to the outflow end 1168 thereof. In an embodiment, the second height H2 is between 0 % and 250 % longer thanthe first height Hl . In an embodiment, the height Hl of the outer frame 1120 is relative to the height H2 of the inner frame 1140 at a ratio of 1.0 : 2.0. Stated another way, the inner frame 1140 may be up to 2.0 times taller than the outer frame 1120, with the inner frame 1140 being 2.0 times taller as the maximum condition and the inner frame 1140 being the same size as the outer frame 820 being the minimum condition. In an embodiment, the height Hl of the outer frame 1120 may be between 5mm - 35mm, and the height H2 of the inner frame 1140 may be between 15mm - 100mm. Generally, the height Hl of the outer frame 1120 is less than that of conventional transcatheter heart valve prostheses having dual frames configured for placement in a native mitral valve known to those having ordinary skill in the art. By shortening the height Hl of the outer frame 1120, protrusion of the outer frame 1120 into a ventricle of a native atrioventricular valve is prevented, and thus improving the uninterrupted flow of fluid through the transcatheter heart valve prosthesis as shown and described herein.

[0280] Although shown with the outer frame configuration comprising two rows of diamond-shaped openings, it will be understood by those of ordinary skill in the art that the connecting members and connection bridges may be used with any of the outer frame designs of other embodiments described herein, as well as alternative outer frame designs. Similarly, the cell or opening pattern of the inner frame 1140, 1240 may vary from the particular configuration described herein.

[0281] FIG. 13 A depicts an embodiment of an outer frame 1320 that may be utilized as the outer frame in any embodiment described herein. The outer frame 1320 includes a plurality of axial struts 1371, an inflow ring 1374, and a plurality of migration resistance features 1370. Each axial strut 1371 extends parallel to a longitudinal axis of the outer frame 1320. The inflow ring 1374 has a sinusoidal pattern formed by a plurality of struts 1330 and a plurality of crowns 1332, with each crown 1332 being formed between a pair of opposing struts 1330. The inflow ring 1374 is oriented parallel to the longitudinal axis of the outer frame 1320, and forms the inflow end of the outer frame 1320. The outer frame 1320 comprising three rows of openings 1328. Each opening of the three rows of openings 1328 is partially defined by a migration resistance feature 1370, which increases the migration resistance of a transcatheter heart valve prosthesis, and is also partially defined by a portion a pair of adjacent axial struts 1371. Each migration resistance feature 1370 provides greater flexibility and greater engagement with native tissue structures including the annulus, chordea, and commissure regions, compared to the traditional cactus cleats. Anenlarged view of a single migration resistance feature 1370 is depicted in FIG. 13B. Each migration resistance feature 1370 includes a pair of struts 1372 forming a chevron which are configured to extend radially outwards from the outer frame 1320. The pair of struts 1372 form a chevron are oriented such that a tip 1373 of the chevron points towards the inflow end of the outer frame 1320. The chevron extends between a pair of adjacent axial struts 1371. The migration resistance feature 1370 may be used in every row of openings as depicted in the embodiment of FIG. 13A, or may be used only in some rows of openings, or may be used only in an endmost outflow row of openings.

[0282] FIG. 14A depicts an embodiment of an outer frame 1420 that may be utilized as the outer frame in any embodiment described herein. The outer frame 1420 includes two rows of openings 1428A, 1428B. In this embodiment, the number of openings 1428A in the first row of openings 1428A is equal to the number of openings 1428B in the second row of openings 1428B. The first row of openings 1428A is formed via a plurality of struts 1430 and a plurality of crowns 1432, with each crown 1432 being formed between a pair of opposing struts 1430. Each opening 1428A of the first row of openings 1428A is substantially diamond or spade shaped. The second row of openings 1428B is at least partially formed via a plurality of axial struts 1471 and a plurality of migration resistance features 1470. Each axial strut 1471 extends parallel to a longitudinal axis of the outer frame 1420. In this embodiment, each axial strut 1471 is axially aligned with an endmost inflow crown 1432 and the number of endmost inflow crowns 1432 is equal to the number of axial struts 1471. As such, an axial strut 1471 is disposed longitudinally adjacent to every endmost inflow crown 1432. Each opening of the second row of openings 1428B is partially defined by a migration resistance feature 1470, which increases the migration resistance of a transcatheter heart valve prosthesis, and is also partially defined by a portion a pair of adjacent axial struts 1471. Each migration resistance feature 1470 provides greater flexibility and greater engagement with native tissue structures including the annulus, chordea, and commissure regions, compared to the traditional cactus cleats. An enlarged view of a single migration resistance feature 1470 is depicted in FIG. 14B. Each migration resistance feature 1470 includes a pair of struts 1472 forming a chevron which are configured to extend radially outwards from the outer frame 1420. The pair of struts 1472 form a chevron are oriented such that a tip 1473 of the chevron points towards the inflow end of the outer frame 1420. The chevron extends between a pair of adjacent axial struts 1471. Migration resistance feature 1470 is similar to the previous described migrationresistance feature 1370, but is provided with a cleat 1426 extending from the tip 1473 of the pair of struts 1472 forming the chevron.

[0283] FIG. 15 depicts an embodiment of an outer frame 1520 that may be utilized as the outer frame in any embodiment described herein. The outer frame 1520 includes two rows of openings 1528A, 1528B. In this embodiment, the number of openings 1528A in the first row of openings 1528A is double or twice the number of openings 1528B in the second row of openings 1528B. The first row of openings 1528A is formed via a plurality of struts 1530 and a plurality of crowns 1532, with each crown 1532 being formed between a pair of opposing struts 1530. Each opening 1528 A of the first row of openings 1528A is substantially diamond or spade shaped. The second row of openings 1528B is at least partially formed via a plurality of axial struts 1571 and a plurality of migration resistance features 1570. Each axial strut 1571 extends parallel to a longitudinal axis of the outer frame 1520. In this embodiment, each axial strut 1571 is axially aligned with an endmost inflow crown 1532 and the number of endmost inflow crowns 1532 is double or twice the number of axial struts 1571. As such, an axial strut 1571 is disposed adjacent to every other endmost inflow crown 1532 in an alternating fashion. Each opening of the second row of openings 1528B is partially defined by a migration resistance feature 1570, which increases the migration resistance of a transcatheter heart valve prosthesis, and is also partially defined by a portion a pair of adjacent axial struts 1571. Each migration resistance feature 1570 provides greater flexibility and greater engagement with native tissue structures including the annulus, chordea, and commissure regions, compared to the traditional cactus cleats. Each migration resistance feature 1570 includes a pair of struts 1572 forming a chevron which are configured to extend radially outwards from the outer frame 1520. The pair of struts 1572 form a chevron are oriented such that a tip 1573 of the chevron points towards the inflow end of the outer frame 1520. The chevron extends between a pair of adjacent axial struts 1571. Migration resistance feature 1570 is similar to the previous described migration resistance feature 1370, but is provided with a cleat 1526 extending from the tip 1573 of the pair of struts 1572 forming the chevron. Migration resistance feature 1570 is substantially similar to the migration resistance feature 1470, but has a greater width due to the relatively greater width of the openings 1528B of the second row of openings 1528B compared to the width of the openings 1428B of the second row of openings 1428B.

[0284] FIG. 16 depicts a migration resistance feature 1670 that may be alternatively used as the migration resistance feature 1570 of FIG. 15. Migration resistance feature 1670 a total of four struts 1672 forming a double chevron, or “M” shape. More particularly, migration resistance feature 1670 includes two chevrons, each of which is configured to extend radially outwards from the outer frame. Each chevron is oriented such that a tip 1673 of the chevron points towards the inflow end of the outer frame. Although not shown, cleats may be attached to each of the tips 1673 that are formed by the double chevron.

[0285] The aforementioned embodiments of the migration resistance features are not intended to be limiting but are provided as examples. Migration resistance features with any combination of the discussed characteristics (different widths, number of chevrons, inclusion or exclusion of cleats) may be used with any compatible outer frame of a transcatheter heart valve prosthesis described herein.

[0286] FIG. 17 depicts a transcatheter heart valve prosthesis 1700 according to an eleventh embodiment. The transcatheter heart valve prosthesis 1700 depicts an embodiment wherein the outer frame 1720 and inner frame 1740 are substantially similar to the outer frame and inner frame of FIGS. 3A-D. However, the transcatheter prosthesis is intended to be implanted in a reversed orientation relative to the aforementioned embodiments, with inflow ends 1736, 1762 of the outer and inner frames, respectively, being disposed on an atrial side of a native mitral valve and outflow ends 1738, 1768 of the outer and inner frames, respectively, being disposed downstream of the respective inflow ends. In order to achieve this, the features of the prosthesis 1700 such as the valve structure, the cleats, and the migration resistance features, are all oriented in an opposite longitudinal direction relative to the outer frame and the inner frame, compared to the aforementioned embodiments. Accordingly, when the prosthesis is flipped, as depicted in FIG. 17, the valve structure, cleats, and migration resistance features are all properly oriented within the mitral valve annulus.

[0287] Furthermore, while the embodiment depicted in FIG. 17 has been discussed in detail, a similar modification may be performed on any of the embodiments discussed herein. Therefore, any of the aforementioned embodiments may also be constructed with any of the valve structure, cleat, or migration resistance features oriented in a reversed direction relative to the inner and outer frames, such that the transcatheter heart valve prosthesis may be implanted in a reversed orientation.

[0288] FIGS. 18A-18F depict a dual frame stent structure 1810 according to an eleventh embodiment hereof. The dual frame stent structure 1810 comprises an inner frame 1840 and an outer frame 1820 which circumferentially surrounds at least a portion of the inner frame 1840. The inner frame 1840 is substantially or predominantly cylindrical, while the outer frame 1820 includes an outflow or distal tapered region as will be described in more detail herein. In addition, the outer frame 1820 includes a plurality of connector struts 1850 that extend between and connect the outer frame 1820 to the inner frame 1840 and a plurality of hanging fixation cells that are longitudinally aligned with but radially outwardly offset from the connector struts 1850 as will be described in more detail herein. As shown in FIGS. 18A-18E, each connector strut 1850 of the plurality of connector struts 1850 extends radially inward from a midportion of the outer frame 1820 and are attached to an outflow end of the inner frame 1840. The hanging fixation cells are disconnected from, and not directly attached to, the outflow end of the inner frame 1840. In this embodiment, the outer frame 1820 further includes an outflow support ring 1876 as will be described in more detail herein.

[0289] The dual frame stent structure 1810 is intended to form the scaffolding of a transcatheter heart valve prosthesis 1800 having a prosthetic valve component (such as the prosthetic valve component 206) disposed within the inner frame 1840. The transcatheter heart valve prosthesis 1800 is configured to have a profile such that an inflow end of the transcatheter heart valve prosthesis 1800 is disposed within and floats freely within a patient’s atrium A and an outflow end of the transcatheter heart valve prosthesis 1800 does not extend or only minimally extends into the patient’s left ventricle LV of the heart to avoid obstruction of the left ventricular outflow tract (LVOT).

[0290] Similar to the dual frame stent structure 210, both the inner frame 1840 and the outer frame 1820 are self-expanding to return to a radially expanded state from a radially compressed state and may be made from materials such as, but not limited to stainless steel, a pseudo-elastic metal such as a nickel titanium alloy (e.g. NITINOL), or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal.

[0291] The inner frame 1840 has a similar pattern of cells or openings as the inner frame 840 described above with respect to the embodiment of FIG. 8A and includes a plurality of openings. In an embodiment, the inner frame 1840 includes exactly two rows of openings, namely a first row of openings and a second row of openings. In an embodiment, the first row of openingsincludes the same number of openings as the second row of openings. In an embodiment, all openings of the first row of openings and the second row of openings are substantially the same size and shape. In an embodiment, each opening of the first row of openings and the second row of openings is formed in a hexagonal shape. In an embodiment, the inner frame 1840 has a total of twelve endmost crowns 1852 at an inflow end 1862 of the inner frame 1840 and a total of twelve endmost crowns 1852 at an outflow end 1868 of the inner frame 1840. It will be understood by those of ordinary skill in the art that the cell or opening pattern of the inner frame may vary from the particular configuration described herein.

[0292] As best shown on the sectional views of FIGS. 18C-18E, the inner frame 1840 defines a lumen 1841 from the inflow end 1862 of the inner frame 1840 to the outflow end 1868 of the inner frame 1840. The inflow end 1862 of the inner frame 1840 defines the inflow end of the dual frame stent structure 1810. The prosthetic valve component 206, described in detail above, is disposed within the lumen 1841 of the inner frame. The inner frame 1840 has a cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 1800. An outer diameter of the inner frame 1840 does not vary, or is constant, along the entire length thereof.

[0293] The outer frame 1820 of the dual frame stent structure 1810 includes a fixation region 1822, the connector struts 1850, and the outflow support ring 1876. The fixation region 1822 circumferentially surrounds at least a portion of the inner frame 1840. The fixation region 1822 includes an inflow end 1836 and an outflow end 1838. In this embodiment, a fixation region 1822 of the outer frame 1820 includes a proximal or inflow cylindrical portion 1821 and a distal or outflow tapered portion 1823 extending distally and radially inward from a distal or downstream end of the cylindrical portion 1821. The tapered portion 1823 of the outer frame 1820 may optimize deployment dynamics when deploying the transcatheter heart valve prosthesis 1800 from a delivery system into the atrium. The tapered portion 1823 of the outer frame 1820 may further optimize the structural integrity and durability of the dual frame stent structure 1810 by allowing flexion between the outer frame 1820 and the inner frame 1840 when subjected to forces created by events such as loading into a delivery system (not shown), deployment into the heart, and / or the flow of fluids therethrough. The outer frame 1820 may optionally include a flange orbrim (not shown) extending radially outward from a proximal or upstream end of the fixation region 1822 of the outer frame 1820, as described in more detail herein with respect to FIG. 7.

[0294] The cylindrical portion 1821 has a cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 1800. The cylindrical portion 1821 has a first or upstream end 1890 of the cylindrical portion 1821 defining an inflow end of the fixation region 1822 of the outer frame 1820. The first or upstream end 1890 of the cylindrical portion 1821 has an outer diameter DI. A second or downstream end 1892 of cylindrical portion 1821 of the outer frame 1820 is integrally formed with or coextensive with a first or upstream end 1894 of the tapered portion 1823 of the outer frame 1820, and a second or downstream end 1896 of the tapered portion 1823 defines an outflow end 1838 of the fixation region 1822. In an embodiment, the second or downstream end 1892 of cylindrical portion 1821 and the coextensive first or upstream end 1894 of the tapered portion 1823 have the outer diameter DI such that the outer diameter of the cylindrical portion 1821 may be described as being constant along the entire length thereof. The second or downstream end 1896 of the tapered portion 1823 defining the outflow end 1838 of the fixation region 1822 has an outer diameter D2 (shown in FIG. 18B) that is less than the outer diameter DI.

[0295] The fixation region 1822 is configured to securely fix the outer frame 1820 to engage heart tissue at or below an annulus of a native heart valve, such as an annulus of a native mitral valve. The fixation region 1822 may be configured to engage subannular tissue, such as inward-facing surfaces of the native valve leaflets. The fixation region 1822 functions as an anchor for the transcatheter heart valve prosthesis 1800 to secure its deployed position within a native annulus. In an aspect of the disclosure, the fixation region 1822 includes one or more rows of cleats or prongs 1826 (best shown on FIG. 18F) that extend upstream or upward (towards the inflow end) and / or radially outward from an outer wall or surface of the fixation region 1822 to engage heart tissue. The cleats 1826 may be configured to penetrate the native tissue to facilitate retention or maintain position of the transcatheter heart valve prosthesis 1800 in a desired implanted location. In another aspect of the disclosure, as an alternative to a cleat structure, the fixation region 1822 may employ barbs, spikes, or other tissue fixation mechanisms for engaging heart tissue. In an embodiment, as shown on FIG. 18F, the outer frame 1820 includes a total of three rows of cleats. In another embodiment hereof, the outer frame 1820 may include a two rows of cleats or a single row of cleats.

[0296] The fixation region 1822 of the outer frame 1820 includes a plurality of openings 1828 that are formed by a plurality of struts 1830 and a plurality of crowns 1832, with each crown1832 being formed between a pair of opposing struts 1830. Each crown 1832 is a curved segment or bend extending between opposing struts 1830. In an embodiment, the fixation region 1822 has a total of twenty -four endmost crowns 1832 at the inflow end 1836 of the fixation region 1822 and a total of twelve endmost crowns 1832 at the outflow end 1838 of the fixation region 1822. In an embodiment, the fixation region 1822 includes exactly three rows of openings 1828, namely a first row of openings 1828A, a second row of openings 1828B, and a third row of openings 1828C. The first row of openings 1828A is formed at the inflow end 1836 of the fixation region 1822, the third row of openings 1828C is formed at the outflow end 1838 of the fixation region 1822, and the second row of openings 1828B extends between the first and third rows of openings 1828A and 1828C, respectively. In an embodiment, the cylindrical portion 1821 of the fixation region 1822 includes the first row of openings 1828A and the tapered portion 1823 of the fixation region 1822 includes the third row of openings 1828C, while the second row of openings 1828B is within both the cylindrical portion 1821 and the tapered portion 1823. More particularly, in an embodiment, the two adjacent endmost struts 1830 of the second row of openings 1828B closest to the outflow end 1838 are within the tapered portion 1823 of the fixation region 1822.

[0297] In an embodiment, all openings of the fixation region 1822 within the first row of openings 1828A, the second row of openings 1828B, and the third row of openings 1828C are substantially the same shape. In an embodiment, within the fixation region 1822, each opening of the first row of openings 1828A, the second row of openings 1828B, and the third row of openings 1828C is formed in a diamond or hexagonal shape. The third row of openings 1828C, along with the two adjacent endmost struts 1830 of the second row of openings 1828B closest to the outflow end 1838, do not extend parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 1800 but rather tapers radially inward.

[0298] The outer frame 1820 also includes support openings or cells 1895, which are formed by the endmost outflow struts 1830 of the fixation region 1822, the connector struts 1850 and the outer support ring 1876. When the outer frame 1820 is expanded or deployed, the support openings or cells 1895 are oriented or rotated to face radially inwards and thus are not configured to face or abut native tissue, and therefore are not considered to be openings or cells of the fixation portion 1822. To clearly understand the structure of the support openings 1895, the outflow support ring 1876 will first be described in more detail. The outflow support ring 1876 provides / increases radial force of the outer frame 1820 at the outflow end thereof. The outflow support ring 1876includes a plurality of struts 1830C and a plurality of crowns 1832C, with each crown 1832C being formed between a pair of opposing struts 1830C. Each crown 1832C is a curved segment or bend extending between opposing struts 1830C. The outflow support ring 1876 is at least partially oriented transverse to blood flow, with each strut 1830C extending between an intermediate portion of a connector strut 1850 and an outflow end of an opening 1828C of the third row of openings 1828C within the fixation region 1822. Due to the orientation of the outflow support ring 1876, the endmost outflow crowns 1832C thereof are radially spaced apart. Each endmost outflow crown 1832C of the outflow support ring 1876 that is attached to a connector strut 1850 is spaced radially inwards relative to each endmost outflow crown 1832C of the outflow support ring 1876 that is attached to an outflow end of an opening 1828C of the third row of openings 1828C within the fixation region 1822. For purposes of this description, such endmost outflow crowns of the outflow support crown 1832C that are attached to connector struts 1850 are labeled as a first set of endmost outflow crowns 1832C1 and such endmost outflow crowns of the outflow support crown 1832C that are attached to the outflow ends of the openings 1828C within the fixation region 1822 are labeled as a second set of endmost outflow crowns 1832C2. The endmost outflow crowns 1832C1, 1832C2 have an alternating pattern, with each crown 1832C1 being disposed between a pair of adjacent crowns 1832C2 and each crown 1832C2 being disposed between a pair of adjacent crowns 1832C1. As best shown on FIG. 18B, the outflow support ring 1876 may be considered to have the outer diameter D2 (formed by the second set of endmost outflow crowns 1832C2) and an inner diameter D3 (formed by the first set of endmost outflow crowns 1832C1), with the inner diameter D3 being less than the outer diameter D2 and greater than an outer diameter D4 of the inner frame 1840.

[0299] To further illustrate the placement of the outflow support ring 1876, FIGS. 18C, 18D, and 18E illustrate schematic sectional views of the transcatheter heart valve prosthesis 1800, taken along lines C-C, D-D, and E-E of FIG. 18B, respectively. In FIG. 18C, taken through a pair of endmost outflow crowns 1832C1, it is shown that the endmost outflow crowns 1832C1 of the outflow support ring 1876 are connected to a connector strut 1850 adjacent to, but radially spaced apart from, the inner frame 1840. In FIG. 18D, taken through a pair of endmost outflow crowns 1832C2, it is shown that the endmost outflow crowns 1832C2 of the outflow support ring 1876 are connected to the outflow ends of the openings 1828C of the third row of openings 1828C. In FIG. 18E, taken at a location between adjacent endmost outflow crowns 1832C1, 1832C2, it isshown that the struts 1830C of the outflow support ring 1876 are radially disposed between the outflow ends of the openings 1828C of the third row of openings 1828C and the inner frame 1840. [003001 In this embodiment, as shown in the schematic sectional views of FIGS. 18C-18E, the inner frame 1840 includes a sealing member or skirt 1809 coupled to the inner and / or outer surface of the inner frame 1840. The inner skirt 1809 is coupled to the full length of the inner frame 1840. An outer skirt 1808 covers a portion of the outer frame 1820. More particularly, the outer skirt 1808 covers at least the first row of openings 1828A and bridges from the outer frame 1820 to the inner frame 1840. As shown in FIG.18C, the outer skirt 1808 is coupled to the connector struts 1850. However, between the connector struts 1850 as shown in each of FIGS. 18D and 18E, the outer skirt 1808 bridges from the outer frame 1820 to the inner frame 1840 and is unsupported (i.e., not sutured to any support member or strut).

[0301] With the outflow support ring 1876 fully described, the structure of each support opening 1895 will now be discussed in more detail. As shown in FIGS. 18A and 18F, each support opening 1895 is formed by two endmost struts 1830 of the outflow end 1838 of the fixation region 1822, a connector strut 1850, and a strut 1830C of the outflow support ring 1876. Two support openings 1895 are disposed between a pair of adjacent openings 1828C of the third row of openings 1828C of the fixation region 1822. Stated another way, the support openings 1895 and the openings 1828C are circumferentially disposed in a pattern including an opening 1828C, two support openings 1895, and another opening 1828C. Due to the trajectory of the connector struts 1850, each support opening 1895 is configured or oriented so as to not face or abut native tissue while each opening 1828C is configured or oriented so as to face or abut native tissue.

[0302] Due to the orientation of the support openings 1895, the support openings 1895 may be considered to extend radially between the connector struts 1850 and the openings 1828C of the fixation region 1822. This configuration provides the tapered region 1823 of the fixation region 1822 with less of an acute angle radially inwards than the connector struts 1850 and thus increases fixation of the outer frame 1820 within the native anatomy. Stated another way, the third row of openings 1828C of the fixation region 1822, which includes a row of cleats 1826, are disposed radially outwards relative to the connector struts 1850 and the support openings 1895. This radially offset placement between the connector struts 1850 and the third row of openings 1828C and cleats associated therewith provides better fixation within the native anatomy. With the connector struts 1850 extending at a sharper radially inward path to provide connection to the innerframe, the third row of openings 1828C may be considered “hanging fixation cells” that are longitudinally aligned and radially outwardly offset from the connector struts 1850 to thereby position the cleats associated therewith closer to the native anatomy for better fixation. The openings 1828C or hanging fixation cells are disconnected from, or not directly attached to, the outflow end of the inner frame 1840. The openings 1828C or hanging fixation cells flare radially outwards relative to the connective struts 1850 and do not follow the profile or contour of the connector struts 1850 to enhance fixation and increase anti -migration.

[0303] In some embodiments, the openings 1828C or hanging fixation cells comprises an uncovered portion which does not receive graft material. More particularly, in an embodiment, the outer skirt 1808 is coupled to the inflow portion of the outer frame 1820 upstream of the connector struts 1850, and is also coupled to and between the connector struts 1850 as described above with respect to FIGS. 18C-18E. The openings 1828C or hanging fixation cells are an uncovered portion of the outer frame 1820 that does not have any sealing member or skirt attached thereto and is not covered by any type of graft material, i.e., sealing member or skirt, and blood may flow therethrough. Providing the lower, radially outward portion of the outer frame 1820 as uncovered may reduce LVOTO.

[0304] As best shown on FIG. 18F, which is a schematic view of the outer frame 1820 laid flat as-formed or cut for illustrative purposes only, the plurality of connector struts 1850 and the outflow support ring 1876 are integrally formed with the fixation region 1822 of the outer frame 1820. The outer frame 1820 may be formed by a laser-cut manufacturing method and / or other conventional frame forming methods. For example, the outer frame 1820 may be laser cut from a single metal tube into the desired geometry, creating a tubular scaffold of interconnected struts and crowns that form the openings 1828 of the fixation region 1822, the support openings 1895, and the plurality of connector struts 1850.

[0305] The outer frame 1820 and the inner frame 1840 are attached to each other via the plurality of connector struts 1850. More particularly, the plurality of connector struts 1850 form a connection from a midpoint of the outer frame 1820 to the plurality of endmost outflow crowns 1852 of the inner frame 1840. As stated above, the plurality of connector struts 1850 are integrally formed with the outer frame 1820. Each connector strut 1850 is a substantially straight segment that extends between an midportion of the second row of openings 1828B and an eyelet 1839 (best shown on FIG. 18F). The inner frame 1840 includes a plurality of eyelets (not shown) formedintegrally with the endmost or distal-most outflow crowns 1852. Respective eyelets of the outer frame 1820 and the inner frame 1840 are aligned and attached via rivets (not shown) to formed a plurality of connection points between the outer frame 1820 and the inner frame 1840 together. However, in other embodiments, threads, adhesives, solder, laser welding, metal bolts or other mechanical features, or other types of fasteners can be used to secure the inner frame 1840 to the outer frame 1820. In an embodiment, the outer frame 1820 and the inner frame 1840 are attached to each other at exactly twelve connection points.

[0306] The connector struts 1850 of the present embodiment provide a number of advantages. With the connector struts 1850 extending from a midportion of the outer frame, and disposing the connector struts 1850 at a radially offset position from openings 1828C or hanging fixation cells of the third row of openings 1828C and cleats associated therewith, provides between fixation of the outer frame 1820 within the native anatomy as described above. Further, since the connector struts 1850 are circumferentially offset from the openings 1828C or hanging fixation cells and cleats associated therewith, the outer frame 1820 has a reduced profile when crimped because stacking of such components is avoided. Further, when crimped, the struts 1830C of the outflow support ring 1876 nest within the support openings 1895 results in a shorter overall frame height when crimped. Additionally, the connector struts 1850 exert an outward radial force when under an axial load. More particularly, axial forces directed towards the inflow direction, resulting from mitral valve backflow, cause the connector struts 1850 to exert outward radial forces. The increased radial forces resist migration of the prosthesis.

[0307] With reference to FIG. 18A-18C, when the dual frame stent structure 1810 is in its radially expanded configuration, the fixation region 1822 of the outer frame 1820 is radially spaced from the inner frame 1840. As such, forces from the native anatomy during operation of the native valve after the transcatheter heart valve prosthesis has been implanted are primarily absorbed by the outer frame 1820 such that the inner frame 1840 and the prosthetic valve component 206 coupled thereto remain substantially undeformed. In other words, the inner frame 1840 and prosthetic valve component 206 are effectively mechanically isolated from the distorting forces exerted on the outer frame 1820 by the native tissue, e.g., radially compressive forces exerted by the native annulus and / or leaflets, longitudinal diastolic and systolic forces, hoop stress, etc.

[0308] FIGS. 19A-19D depicts a transcatheter heart valve prosthesis 1900 including a dual frame stent structure 1910 according to a twelfth embodiment hereof. The dual frame stentstructure 1910 is the same as the dual frame stent structure 1810, except that the outflow support ring 1876 of the dual frame stent structure 1810 is omitted. In this embodiment, the outer frame 1920 includes exactly three rows of openings 1928, namely a first row of openings 1928 A, a second row of openings 1928B, and a third row of openings 1928C. The first row of openings 1928A is formed at the inflow end 1936 of the outer frame 1920, the third row of openings 1928C is formed at the outflow end 1938 of the outer frame 1920, and the second row of openings 1928B extends between the first and third rows of openings 1928A and 1928C, respectively. A cylindrical portion 1921 of the outer frame 1920 includes the first row of openings 1928A and a tapered portion 1923 of the outer frame 1920 includes the third row of openings 1928C, while the second row of openings 1928B is within both the cylindrical portion 1921 and the tapered portion 1923. More particularly, in an embodiment, the two adjacent endmost struts 1930 of the second row of openings 1928B closest to the outflow end 1938 are within the tapered portion 1923 of the outer frame 1920. In another embodiment hereof (not shown), the distal or outflow tapered portion 1923 does not extend radially inward, and rather may maintain the same diameter to the cylindrical portion 1921 and / or the distal or outflow tapered portion 1923 may extend radially outward to have a larger diameter relative to the cylindrical portion 1921. Stated another way, the third row of openings 1928C, along with the two adjacent endmost struts 1930 of the second row of openings 1928B closest to the outflow end 1938 may extend parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 1900 or may extend radially outward relative to the longitudinal axis LA. Regardless of the outer diameter of the distal or outflow tapered portion 1923, connector struts 1950 still extend radially inwards to connect the outer frame 1920 to the inner frame 1940. The connector struts 1950 are shown in dotted lines in FIG. 19A for sake of illustration only, to clearly illustrate the structure of the outer frame 1920 that is extending radially inwards for connection to the inner frame 1940.

[0309] In an embodiment, all openings of the first row of openings 1928 A, the second row of openings 1928B, and the third row of openings 1928C are substantially the same shape. In an embodiment, each opening of the first row of openings 1928 A, the second row of openings 1928B, and the third row of openings 1928C is formed in a diamond or hexagonal shape. The third row of openings 1928C, along with the two adjacent endmost struts 1930 of the second row of openings 1928B closest to the outflow end 1938, do not extend parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 1900 but rather tapers radially inward. The first row ofopenings 1928A and the second row of openings 1928B have the same number of openings. The third row of openings 1928C has half the number of openings as the first and second rows of openings 1928A, 1928B. Each opening 1928C of the third row of openings 1928C is disposed directly adjacent to a connector strut 1950, such that a connector strut 1950 is disposed between a pair of openings 1928C of the third row of openings 1928C. Thus, the openings 1928C of the third row of openings 1928C may be considered non-continuous since the openings 1928C are not disposed directly adjacent to each other but rather are disposed in an alternating fashion relative to the connector struts 1950.

[0310] Since the third row of openings 1928C are not directly connected to the connector struts 1950, the third row of openings 1928C are disposed radially outwards relative to the connector struts 1950. This radially offset placement between the connector struts 1950 and the third row of openings 1928C and cleats associated therewith provides better fixation within the native anatomy. Stated another way, with the connector struts 1950 extending at a sharper radially inward path to provide connection to the inner frame, the third row of openings 1928C may be considered “hanging fixation cells” that are longitudinally aligned and radially outwardly offset from the connector struts 1950 to thereby position the cleats associated therewith closer to the native anatomy for better fixation. The hanging fixation cells are disconnected from, or not directly attached to, the outflow end of the inner frame 1940. The hanging fixation cells flare radially outwards and do not follow the profile or contour of the connector struts 1950 to enhance fixation and increase anti -migration.

[0311] FIGS. 20A-20D depicts a transcatheter heart valve prosthesis 2000 including a dual frame stent structure 2010 according to a thirteenth embodiment hereof. The dual frame stent structure 2010 is the same as the dual frame stent structure 1910, except that a plurality of connector struts 2050 thereof have a different length and placement than the plurality of connector struts 1850 / 1950. The connection struts 2050 are relatively shorter in length than the connection struts 1850 / 1950. The connector struts 2050 are shown in dotted lines in FIG. 20A for sake of illustration only, to clearly illustrate the structure of the outer frame 2020 that is extending radially inwards for connection to the inner frame 2040. Each connection strut 2050 is a substantially straight segment that extends between an outflow end of a second row of openings 2028B and an eyelet 2039 (best shown on FIG. 20D).

[0312] Similar to the previous embodiments, the outer frame 2020 includes exactly three rows of openings 2028, namely a first row of openings 2028A, a second row of openings 2028B, and a third row of openings 2028C. The first row of openings 2028A is formed at the inflow end 2036 of the outer frame 2020, the third row of openings 2028C is formed at the outflow end 2038 of the outer frame 2020, and the second row of openings 2028B extends between the first and third rows of openings 2028 A and 2028C, respectively. A cylindrical portion 2021 of the outer frame 2020 includes the first row of openings 2028A and a tapered portion 2023 of the outer frame 2020 includes the third row of openings 2028C, while the second row of openings 2028B is within both the cylindrical portion 2021 and the flared portion 2023. More particularly, the two adjacent endmost struts 2030 of the second row of openings 2028B closest to the outflow end 2038 are within the tapered portion 2023 of the outer frame 2020. The two adjacent endmost struts 2030 of the second row of openings 2028B closest to the outflow end 2038 are shown in dotted lines in FIG. 20A for sake of illustration only, to clearly illustrate the structure of the outer frame 2020 that is extending radially inwards for connection to the inner frame 2040.

[0313] FIGS. 21A and 21B depict an embodiment of an outer frame 2120 that may be utilized as the outer frame of the transcatheter heart valve prosthesis 1800 described herein. Similar to the outer frame 1820, the outer frame 2120 includes an outflow or distal tapered region. In addition, the outer frame 2120 includes a plurality of connector struts 2150 that connect the outer frame 2120 to an inner frame and a plurality of hanging fixation cells that are longitudinally aligned with but radially outwardly offset from the connector struts 2150 as will be described in more detail herein. Each connector strut 2150 of the plurality of connector struts 2150 extends radially inward from a midportion of the outer frame 2120 and are attached to an outflow end of the inner frame. The hanging fixation cells are disconnected from, and not directly attached to, the outflow end of the inner frame 2140. In this embodiment, the outer frame 2120 further includes an outflow support ring 2176 that is attached to the outflow ends of the connector struts 2150 as will be described in more detail herein.

[0314] Similar to previous embodiments described herein, the outer frame 2120 is selfexpanding to return to a radially expanded state from a radially compressed state and may be made from materials such as, but not limited to stainless steel, a pseudo-elastic metal such as a nickel titanium alloy (e g. NITINOL), or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal.

[0315] A fixation region 2122 of the outer frame includes an inflow end 2136 and an outflow end 2138. The fixation region 2122 is configured to securely fix the outer frame 2120 to engage heart tissue at or below an annulus of a native heart valve, such as an annulus of a native mitral valve. In an aspect of the disclosure, the fixation region 2122 includes one or more rows of cleats or prongs 2126 that extend upstream or upward (towards the inflow end) and / or radially outward from an outer wall or surface of the fixation region 2122 to engage heart tissue. The cleats 2126 may be configured to penetrate the native tissue to facilitate retention or maintain position of the transcatheter heart valve prosthesis 2100 in a desired implanted location. In another aspect of the disclosure, as an alternative to a cleat structure, the fixation region 2122 may employ barbs, spikes, or other tissue fixation mechanisms for engaging heart tissue. In an embodiment, as shown on FIG. 21 A, the outer frame 2120 includes a total of three rows of cleats. In another embodiment hereof, the outer frame 2120 may include a two rows of cleats or a single row of cleats.

[0316] Similar to the outer frame 1820, the fixation region 2122 of the outer frame 2120 includes a proximal or inflow cylindrical portion 2121 and a distal or outflow tapered portion 2123 extending distally and radially inward from a distal or downstream end of the cylindrical portion 2121. The cylindrical portion 2121 has a cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis.

[0317] The fixation region 2122 of the outer frame 2120 includes a plurality of openings 2128 that are formed by a plurality of struts 2130 and a plurality of crowns 2132, with each crown 2132 being formed between a pair of opposing struts 2130. Each crown 2132 is a curved segment or bend extending between opposing struts 2130. In an embodiment, the outer frame 2120 has a total of twenty-four endmost crowns 2132 at the inflow end 2136 and a total of twelve endmost crowns 2132 at the outflow end 2138, defined by the outflow support ring 2176. In an embodiment, the outer frame 2120 includes exactly two rows of openings 2128, namely a first row of openings 2128A and a second row of openings 2128B. The first row of openings 2128A is formed at the inflow end 2136 of the outer frame 2120 and the second row of openings 2128B is formed at the outflow end 2138 of the outer frame 2120. In an embodiment, the cylindrical portion 2121 of the outer frame 2120 includes the first row of openings 2128 A, while the second row of openings 2128B is within both the cylindrical portion 2121 and the tapered portion 2123.

[0318] In an embodiment, each opening of the first row of openings 2128A is formed in a diamond or hexagonal shape, and each opening 2128A is the same size. The second row ofopenings 2128B also includes first and second openings 2128B1, 2128B2 formed in a diamond or hexagonal shape, with first openings 2128B1 being relatively larger than second openings 2128B2. The two adjacent endmost struts 2130 of second openings 2128B2 do not extend parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 2100 but rather tapers radially inward. The first openings 2128B1 of the second row of openings 2128B, which includes a row of cleats 2126, are disposed radially outwards relative to the connector struts 2150. This radially offset placement between the connector struts 2150 and the first openings 2128B1 of the second row of openings 2128B and cleats associated therewith provides better fixation within the native anatomy. With the connector struts 2150 extending at a sharper radially inward path to provide connection to the inner frame, the first openings 2128B1 of the second row of openings 2128B may be considered “hanging fixation cells” that are longitudinally aligned and radially outwardly offset from the connector struts 2150 to thereby position the cleats associated therewith closer to the native anatomy for better fixation. The hanging fixation cells are disconnected from, or not directly attached to, the outflow end of the inner frame. The hanging fixation cells flare radially outwards and do not follow the profile or contour of the connector struts 2150 to enhance fixation and increase anti-migration.

[0319] In the embodiment depicted in FIGS. 21A-21B, the outer frame 2120 includes a total of three hanging fixation cells or first openings 2128B1 of the second row of openings 2128B. The first openings 2128 are circumferentially spaced apart around a circumference of the outer frame 2120, at approximately equally spaced intervals. In another embodiment, the outer frame 2120 may include additional hanging fixation cells or first openings 2128B1 of the second row of openings 2128B. More particularly, in another embodiment, the outer frame 2120 may include a total of twelve hanging fixation cells or first openings 2128B1 of the second row of openings 2128B, with a hanging fixation cell or first opening 2128B1 being disposed between each pair of adjacent connector struts 2150.

[0320] In this embodiment, each connection strut 2150 is a substantially straight segment that extends between an outflow end of the second openings 2128B2 of the second row of openings 2128B and an eyelet 2139. As best shown on FIG. 21B, which is a schematic view of a portion of the outer frame 2120 laid flat as-formed or cut for illustrative purposes only, the plurality of connector struts 2150 are integrally formed with the outer frame 2120. The outer frame 2120 may be formed by a laser-cut manufacturing method and / or other conventional frame forming methods.For example, the outer frame 2120 may be laser cut from a single metal tube into the desired geometry, creating a tubular scaffold of interconnected struts and crowns that form the openings 2128 and the plurality of connector struts 2150.

[0321] The outer frame 2120 is configured to attach to the inner frame (not shown) via the plurality of connector struts 2150. More particularly, the plurality of connector struts 2150 form a connection from a midpoint of the outer frame 2120 to the plurality of endmost outflow crowns of the inner frame. As stated above, the plurality of connector struts 2150 are integrally formed with the outer frame 2120. Each connector strut 2150 is a substantially straight segment that extends between an outflow end of the second openings 2128B2 of the second row of openings 2128B and the eyelet 2139. The inner frame includes a plurality of eyelets (not shown) formed integrally with the endmost or distal-most outflow crowns. Respective eyelets of the outer frame 2120 and the inner frame are aligned and attached via rivets (not shown) to formed a plurality of connection points between the outer frame 2120 and the inner frame together. However, in other embodiments, threads, adhesives, solder, laser welding, metal bolts or other mechanical features, or other types of fasteners can be used to secure the inner frame to the outer frame 2120. In an embodiment, the inner frame includes twelve endmost outflow crowns and the outer frame 2120 and the inner frame are attached to each other at exactly twelve connection points.

[0322] The connector struts 2150 of the present embodiment provide a number of advantages. With the connector struts 2150 extending from a midportion of the outer frame, and disposing the connector struts 2150 a radially offset position from the first openings 2128B1 of the second row of openings 2128B and cleats associated therewith, provides between fixation of the outer frame 2120 within the native anatomy as described above. Further, since the connector struts 2150 are circumferentially offset from the first openings 2128B1 of the second row of openings 2128B and cleats associated therewith, the outer frame 2120 has a reduced profile when crimped because stacking of such components is avoided. Additionally, the connector struts 2150 exert an outward radial force when under an axial load. More particularly, axial forces directed towards the inflow direction, resulting from mitral valve backflow, cause the connector struts 2150 to exert outward radial forces. The increased radial forces resist migration of the prosthesis.

[0323] In this embodiment, the outflow support ring 2176 is attached to or extends distally from the outflow ends of the connector struts 2150. The outflow support ring 2176 thus is disposed distally to the connection between the outer frame 2120 and the inner frame. The outflow supportring 2176 includes the endmost outflow struts 2130 and endmost outflow crowns 2132 of the outer frame 2120, and the outflow support ring 2176 provides / increases radial force of the outer frame 2120 at the outflow end 2138. For purposes of this description, such endmost outflow struts and endmost outflow crowns are labeled as struts 2130C and crowns 2132C.

[0324] FIGS. 22A and 22B illustrate a transcatheter heart valve prosthesis 2200 having a barb for use in any of the dual frame stent structures of FIGS. 18A-21B. Similar to the embodiments of FIGS. 18A-21B, an outer frame 2220 of the transcatheter heart valve prosthesis 2200 includes a proximal or inflow cylindrical portion 2221 and a distal or outflow tapered portion 2223 extending distally and radially inward from a distal or downstream end of the cylindrical portion 2221. The outer frame 2220 includes one or more rows of cleats or prongs 2226 that extend upstream or upward (towards the inflow end) and / or radially outward from an outer wall or surface of the outer frame 2220 to engage heart tissue. The cleats 2226 may be configured to penetrate the native tissue to facilitate retention or maintain position of the transcatheter heart valve prosthesis 2200 in a desired implanted location.

[0325] In this embodiment, rather than cleats 2226 near the outflow end of the outer frame 2220, the outer frame 2220 includes a row of barbs 2227 as tissue fixation mechanisms for engaging heart tissue. In an embodiment, the outer frame 2120 includes a total of two rows of cleats 2226 and a single row of barbs 2227. In another embodiment hereof, the outer frame 2220 may include one row of cleats 2226 and two rows of barbs 2227, or one row of cleats 2226 and one row of barbs 2227.

[0326] As best shown on FIG. 22B, which is a schematic view of a portion of the outer frame 2220 laid flat as-formed or cut for illustrative purposes only, each barb 2227 is integrally formed with the outer frame 2220. The outer frame 2220 may be formed by a laser-cut manufacturing method and / or other conventional frame forming methods. For example, the outer frame 2220 may be laser cut from a single metal tube into the desired geometry, creating a tubular scaffold of interconnected struts and crowns that form the openings of the outer frame 2220 and the plurality of barbs 2227.

[0327] Each barb 2227 has a v-shaped configuration with a first leg 2299A and a second leg 2299B, and an apex 2297 formed between the first and second legs 2299A, 2299B. When deployed, each barb 2227 is configured to extend upstream or upward (towards the inflow end) and / or radially outward from an outer wall or surface of the outer frame 2220 to engage hearttissue. In an embodiment, each barb 2227 is configured to extend substantially transverse to blood flow as shown in FIG. 22A. When deployed, the apex 2297 of each barb 2227 is radially spaced apart from the outer surface of the outer frame 2220.

[0328] The barbs 2227 are relatively longer than the cleats 2226. In an embodiment, a length of each barb 2227 is at least twice as a length of each cleat 2226. More particularly, due to the v-shaped configuration thereof, each barb 2227 effectively forms a fixation cell or opening 2229 between the first and second legs 2299A, 2299B to increase length and increase strength of the fixation mechanism as compared to a cleat. In an embodiment, the barbs 2227 deploy or are released after the cleats 2226 and since the barbs 2227 deploy last, the native anterior leaflet may be pulled upwards (towards the inflow end) as the outer frame 2220 foreshortens.

[0329] FIGS. 23A-23F depict a dual frame stent structure 2310 according to a fourteenth embodiment hereof. The dual frame stent structure 2310 comprises an inner frame 2340 and an outer frame 2320 which circumferentially surrounds at least a portion of the inner frame 2340. Similar to the outer frame 1820, the outer frame 2320 includes a tapered portion 2323 and also includes a plurality of connector struts 2350 that connect the outer frame 2320 to the inner frame 2340. However, in the present embodiment, the tapered portion 2323 and the plurality of connector struts 2350 are positioned at or near an inflow end of the dual frame stent structure 2310. The outer frame 2320 further includes an inflow support ring 2376 that is attached to the inflow ends of the connector struts 2350 and a plurality of downstream migration resistance features 2370. Each downstream migration resistance feature 2370 includes a downstream-extending cleat 2326D that extends in a downstream direction, as will be described in more detail herein.

[0330] The dual frame stent structure 2310 is intended to form the scaffolding of a transcatheter heart valve prosthesis 2300 having a prosthetic valve component (such as the prosthetic valve component 206) disposed within the inner frame 2340. The dual frame stent structure 2310 may also include one or more sealing members or skirts coupled to the inner and / or outer surfaces of the inner frame 2340 and the outer frame 2320, as similarly described with respect to the first and second skirts 208, 209 of the transcatheter heart valve prosthesis 200. The prosthetic valve component and skirts are not shown on FIGS. 23A-23F for sake of clarity, to better illustrate the configuration of the dual frame stent structure 2310. The transcatheter heart valve prosthesis 2300 is configured to have a profile such that an outflow end of the transcatheter heart valve prosthesis 2300 is disposed within and floats freely within a patient’s left ventricle, but onlyminimally extends into the patient’s left ventricle LV of the heart to avoid excessive obstruction of the left ventricular outflow tract (LVOT).[003311 Similar to previous embodiments hereof, both the inner frame 2340 and the outer frame 2320 are self-expanding to return to a radially expanded state from a radially compressed state and may be made from materials such as, but not limited to stainless steel, a pseudo-elastic metal such as a nickel titanium alloy (e.g. NITINOL), or a so-called super alloy, which may have a base metal of nickel, cobalt, chromium, or other metal.

[0332] The inner frame 2340 is substantially similar in structure to the inner frame 840 in FIG. 8F. However, unlike the inner frame 840, the inner frame 2340 includes a plurality of eyelets 2359 at the endmost inflow crowns 2352, rather than the endmost outflow crowns 2352. The eyelets 2359 at an inflow end 2362 of the inner frame 2340 and a plurality of eyelets 2339 at an inflow end 2336 of the outer frame 2320 are aligned and attached via rivets (not shown) to attach the outer frame 2320 and the inner frame 2340 together. The inflow end 2362 of the inner frame 2340 and the inflow end 2336 of the outer frame 2320 thus together form the inflow end of the dual frame stent structure 2310. However, in other embodiments, threads, adhesives, solder, laser welding, metal bolts or other mechanical features, or other types of fasteners can be used to secure the inner frame 2340 to the outer frame 2320. In an embodiment, the outer frame 2320 and the inner frame 2340 are attached to each other at exactly twelve connection points.

[0333] As best shown on FIG. 23 C, the inner frame 2340 includes a plurality of openings 2346 formed by a plurality of struts 2354 and a plurality of crowns 2352, with each crown 2352 being formed between a pair of opposing struts 2354. Each crown 2352 is a curved segment or bend extending between opposing struts 2354. In an embodiment, the inner frame 2340 includes exactly two rows of openings 2346, namely a first row of openings 2346A and a second row of openings 2346B. In an embodiment, the first row of openings 2346A includes the same number of openings as the second row of openings 2346B. In an embodiment, all openings 2346 of the first row of openings 2346A and the second row of openings 2346B are substantially the same size and shape. In an embodiment, each opening 2346 of the first row of openings 2346A and the second row of openings 2346B is formed in a hexagonal shape. In further embodiments, the inner frame 2340 may include three rows of openings 2346. In an embodiment, the inner frame 2340 has a total of twelve endmost crowns 2352 at an inflow end 2362 of the inner frame 2340 and a total of twelve endmost crowns 2352 at an outflow end 2368 of the inner frame 2340. Stated another way,the proximal-most crowns of the first row of openings 2346A form the endmost inflow crowns of the inner frame 2340 and the distal-most crowns of the second row of openings 2346B form the endmost outflow crowns of the inner frame 2340. It will be understood by those of ordinary skill in the art that the cell or opening pattern of the inner frame may vary from the particular configuration described herein.

[0334] The inner frame 2340 defines a lumen 2341 from the inflow end 2362 of the inner frame 2340 to the outflow end 2368 of the inner frame 2340. The prosthetic valve component 206, described in detail above, is disposed within the lumen 2341 of the inner frame. The inner frame 2340 has a cylindrical shape which is oriented to extend generally parallel to the longitudinal axis A of the transcatheter heart valve prosthesis 2300. An outer diameter of the inner frame 2340 does not vary, or is constant, along the entire length thereof.

[0335] The outer frame 2320 of the dual frame stent structure 2310 circumferentially surrounds at least a portion of the inner frame 2340. As best illustrated in FIG. 23 A, the outer frame 2320 has a first length or height Hl from an inflow end 2336 to an outflow end 2338, and the inner frame 2340 has a second length or height H2 from the inflow end 2362 to the outflow end 2368. The second length or height H2 of the inner frame 2340 is greater than the first length or height Hl of the outer frame 2320.

[0336] In this embodiment, the outer frame 2320 includes the proximal or inflow tapered portion 2323 and a distal or outflow cylindrical portion 2321 extending distally from a distal or downstream end of the tapered portion 2323. The cylindrical portion 2321 has a generally cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 2300, but includes portions which are angled, tapered, or flared relative to the longitudinal axis LA as described herein. The tapered portion 2323 of the outer frame 2320 may optimize the structural integrity and durability of the dual frame stent structure 2310 by allowing flexion between the outer frame 2320 and the inner frame 2340 when subjected to forces created by events such as loading into a delivery system (not shown), deployment into the heart, and / or the flow of fluids therethrough.

[0337] The tapered portion 2323 has a first or upstream end 2390 defining an inflow end of the outer frame 2320. The first or upstream end 2390 of the tapered portion 2323 has an outer diameter DI. In an embodiment, the outer diameter DI is between 25 to 31 mm, and in another embodiment is between 27 to 29 mm. A second or downstream end 2392 of the tapered portion2323 of the outer frame 2320 is integrally formed with or coextensive with a first or upstream end 2394 of the cylindrical portion 2321 of the outer frame 2320, and a second or downstream end 2396 of the cylindrical portion 2321 defines an outflow end of the outer frame 2320. The second or downstream end 2392 of tapered portion 2323 and the coextensive first or upstream end 2394 of the cylindrical portion 2321 have an outer diameter D2 that is greater than the outer diameter DI. In an embodiment, the outer diameter D2 is between 50 and 54 mm. In an embodiment, in the direction of bloodflow therethrough, the cylindrical portion 2321 of the outer frame 2320 flares or extends radially outward at the angle 02 (shown on FIG. 23D) to form a flared outflow portion of the outer frame 2320. In an embodiment, angle 02 is between 40° and 50° relative to the central longitudinal axis LA. The second or downstream end 2396 of the cylindrical portion 2321 has an outer diameter D3 that is greater than the outer diameter D2. In an embodiment, the outer diameter D3 is between 52 to 57 mm. With the outflow portion of the cylindrical portion 2321 of the outer frame 2320 flared radially outward rather than parallel to the central longitudinal axis LA, the amount of the outer frame 2320 that protrudes or extends into or around the left ventricular outflow tract (LVOT) is reduced. Thus, obstruction of blood flow through the LVOT may be minimized or prevented with such designs having a flared outflow end of the outer frame. In another embodiment hereof (not shown), outer diameter D2 may be the same as or greater than outer diameter D3.

[0338] In this embodiment, the cylindrical portion 2321 of the outer frame 2320 forms a fixation region 2322 of the outer frame 2320. The fixation region 2322 includes one or more rows of upstream-extending cleats or prongs 2326U that extend upstream or upward (towards the inflow end 2336 of the outer frame 2320) and / or radially outward from an outer wall or surface of the fixation region 2322 to engage heart tissue. The present embodiment further includes downstreamextending cleats or prongs 2326D that extend downstream or downward (towards the outflow end 2338 of the outer frame). The cleats 2326U, 2326D may be configured to penetrate the native tissue to facilitate retention or maintain position of the dual frame stent structure 2310 in a desired implanted location. Together, the cleats 2326U, 2326D extending both upstream and downstream may be configured to provide bi-directional migration resistance with respect to the longitudinal axis LA. In another aspect of the disclosure, as an alternative to a cleat structure, the fixation region 2322 may employ barbs, spikes, or other tissue fixation mechanisms for engaging heart tissue. As best shown in FIGS. 23A and 23D, in an embodiment, the outer frame 2320 includes a total of four rows of cleats 2326U, 2326D. More particularly, a first row of cleats 2326D is disposedproximally, or upstream, relative to each of the other rows. The first row of cleats 2326D extend distally, or downstream, to engage the native tissue. Conversely, the second row of cleats 2326U, the third row of cleats 2326U, and the fourth row of cleats 2326U extend proximally, or upstream, to engage the native tissue. In embodiments hereof, the outer frame 2320 may only include two rows, or a single row, of the up stream -extending cleats 2326U.

[0339] The fixation region 2322 is configured to securely fix the outer frame 2320 to engage heart tissue at or below an annulus of a native heart valve, such as an annulus of a native mitral valve. The fixation region 2322 may be configured to engage subannular tissue, such as inward-facing surfaces of the native valve leaflets. The fixation region 2322 functions as an anchor for the dual frame stent structure 2310 to secure its deployed position within a native annulus. In some embodiments, the fixation region 2322 is shape set with curvatures that mirror or mimic the shape of a mitral annulus to allow for improved conformity when deployed. However, this not meant to be limiting, and in other embodiments, the fixation region 2322 may be generally straight and may help the outer frame 2320 conform to the anatomy by being relatively flexible.

[0340] The outer frame 2320 includes a plurality of openings 2328 that are formed by a plurality of struts 2330 and a plurality of crowns 2332, with each crown 2332 being formed between a pair of opposing struts 2330. Each crown 2332 is a curved segment or bend extending between opposing struts 2330. In an embodiment, the outer frame 2320 has a total of twenty-four endmost crowns 2332 at the outflow end 2338 of the outer frame 2320 and a total of twelve endmost crowns 2332 at the inflow end 2336 of the outer frame 2320. In an embodiment, a ratio of the endmost inflow crowns 2332 of the outer frame 2320 to the endmost inflow crowns 2332 of the outer frame 2320 is 1 : 1. In an embodiment, the outer frame 2320 includes exactly four rows of openings 2328, namely a first row of openings 2328A, a second row of openings 2328B, a third row of openings 2328C, and a fourth row of openings 2328D. The first row of openings 2328A is formed at the inflow end 2336 of the outer frame 2320, the fourth row of openings 2328D is formed at the outflow end 2338 of the outer frame 2320, and the second and third rows of openings 2328B, 2328C extends between the first and fourth rows of openings 2328A and 2328D, respectively. In an embodiment, the cylindrical portion 2321 of the outer frame 2320 includes the third and fourth rows of openings 2328C, 2328D, the tapered portion 2323 includes the first row of openings 2328A, and the second row of openings 2328B is within both the cylindrical portion 2321 and the tapered portion 2323.

[0341] In an embodiment, all openings of the second, third, and fourth rows of openings 2328B, 2328C, 2328D are formed in a diamond or hexagonal shape. The openings of the first row of openings 2328A are formed in an irregular shape, as will be described in more detail herein. The first row of openings 2328A do not extend parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 2300 but rather tapers radially inward.

[0342] More particularly, the first row of openings 2328A includes the plurality of connector struts 2350 that connect the outer frame 2320 to the inner frame 2340. Each connector strut 2350 is a substantially straight segment that extends between the second row of openings 2328B and an eyelet 2339. In addition, the endmost inflow struts 2330 and endmost inflow crowns 2332 of the first row of openings 2328A may be considered to form the inflow support ring 2376, which provides / increases radial force of the outer frame 2320 at the inflow end 2336. For purposes of this description, such endmost inflow struts and endmost inflow crowns are labeled as struts 2330A and crowns 2332A. Each opening of the first row of openings 2328A is formed by two adjacent connector struts 2350, four struts 2330 of the outer frame extending between the two adjacent connector struts 2350, and two struts 2330A of the inflow support ring 2376 extending between the two adjacent connector struts 2350. In this embodiment, the inflow support ring 2376 is attached to or extends distally or downstream from the inflow ends of the connector struts 2350. The inflow ends of the connector struts 2350 comprise eyelets 2339 which are configured to attach to respective eyelets 2359 of the inner frame 2340 as described above. The inflow support ring 2376 thus is disposed distally or downstream to the connections between the outer frame 2320 and the inner frame 2340.

[0343] The second row of openings 2328B includes alternating flared openings or cells 2328B1 and tapered openings or cells 2328B2. More particularly, each opening 2328B1, 2328B2 of the second row of openings 2328B are formed by four struts 2354 of the outer frame 2320. The two adjacent endmost struts 2330 of each opening 2328B1, 2328B2 which are closest to the outflow end 2338 of the outer frame 2320 are oriented substantially parallel to the longitudinal axis LA of the prosthesis. Conversely, the two adjacent endmost struts 2330 of each flared opening 2328B1 which are closest to the inflow end 2336 of the outer frame 2320 are oriented to extend radially outwards relative to the longitudinal axis LA of the prosthesis, while the two adjacent endmost struts 2330 of each tapered opening 2328B2 which are closest to the inflow end 2336 of the outer frame 2320 are oriented to extend radially inwards relative to the longitudinal axis LA ofthe prosthesis. Stated another way, the downstream half of each opening 2328B1, 2328B2 of the second row of openings 2328B is oriented substantially parallel to the longitudinal axis LA of the prosthesis while the upstream half of each opening 2328B 1, 2328B2 of the second row of openings 2328B is oriented to extend radially outwards or radially inwards, respectively. The plurality of flared openings or cells 2328B 1 and the plurality of tapered openings or cells 2328B2 are disposed in an alternating pattern, with each flared opening 2328B1 being disposed between a pair of adjacent tapered cells 2328B2 and each tapered opening 2328B2 being disposed between a pair of adjacent flared cells 2328B1. Stated another way, every other opening in the second row of openings 2328B is a flared opening 2328B 1 and every other opening in the second row of openings is a tapered opening 2328B2.

[0344] A connector strut 2350 extends from an inflow end of each tapered opening or cell 2328B2. A connector strut 2350 thus extends between each tapered opening 2328B and the inner frame 2340. Since the upstream half of each tapered opening 2328B2 is oriented to extend radially inwards, the endmost inflow crown 2332 of each tapered opening or cell 2328B2 is disposed radially inward relative to the endmost outflow crown 2332 of each tapered opening or cell 2328B2. As best shown in FIG. 23D, the inwardly extending struts 2330 of each tapered opening or cell 2328B2 and the connector struts 2350 extend at an angle 0i relative to the central longitudinal axis LA of the outer frame 2320 to form the tapered portion 2323 of the outer frame 2320. In an embodiment, angle 0i is between 50° and 80° relative to the central longitudinal axis LA. In an embodiment, the outer frame 2320 includes a total of twelve tapered openings 2328B2 and twelve connector struts 2350.

[0345] A downstream-extending cleat 2326D extends from an inflow end of each flared opening or cells 2328B1. Since the upstream half of each flared opening 2328B1 is oriented to extend radially outwards, the endmost inflow crown 2332 of each flared opening or cell 2328B1 is disposed radially outward relative to the endmost outflow crown 2332 of each flared opening or cell 2328B1. The endmost inflow crown 2332 of each flared opening or cell 2328B1 is free or not directly attached to a connector strut 2350. The upstream half of the flared openings or cells 2328B 1 flare radially outwards and do not follow the profile or contour of the fixation region 2322 or the connector struts 2350 to enhance fixation and increase anti-migration. Collectively, the outwardly extending struts 2330 of each flared opening or cell 2328B2 and the downstream-extending cleat 2326D forms a downstream migration resistance feature 2370 of the plurality of downstream migration resistance features 2370.

[0346] The plurality of downstream migration resistance features 2370 provide a number of advantages. Primarily, the downstream-extending cleats 2326D engage the native heart tissue to facilitate retention or maintain position of the dual frame stent structure 2310 in a desired implanted location. The cleats 2326D extending in the downstream direction allows them to function in concert with the other upstream-extending cleats 2326U to provide bi-directional migration resistance with respect to the longitudinal axis LA. While the upstream-extending cleats 2326U prevent the prosthesis 2300 from migrating upstream into the atrium, the downstreamextending cleats 2326D prevent the prosthesis 2300 from migrating downstream into the ventricle. Since the risk of prosthesis migration is partially dependent upon the proper placement of the prosthesis, the present embodiment results in a design that is more forgiving to imperfect prosthesis placement and reduces the risk of migration in such cases. Furthermore, the downstream migration resistance features 2370 provide greater flexibility and greater engagement with native tissue structures compared to the traditional cactus cleats because the flared openings or cells 2328B1 are disconnected, providing additional degrees of freedom. Lastly, the downstream migration resistance features 2370 formed by the flared openings or cells 2328B1 provide a platform for a skirt (not shown) to be sewn thereto, or for a radiopaque marker (not shown) to be attached thereto. In embodiments, the skirt allows for easier detection of the prosthesis with ultrasound echocardiogram imaging during deployment. In embodiments, radiopaque markers may additionally or alternatively be attached to the migration resistance features. Radiopaque markers similarly allow for easier detection of the prosthesis with imaging during deployment.

[0347] As best shown on FIG. 23E-23F, which show full and partial / enlarged schematic views of the outer frame 2320 laid flat as-formed or cut for illustrative purposes only, the upstreamextending cleats 2326U, the down-stream extending cleats 2326D, the connector struts 2350, and the inflow support ring 2376 are integrally formed with the outer frame 2320. The outer frame 2320 may be formed by a laser-cut manufacturing method and / or other conventional frame forming methods. For example, the outer frame 2320 may be laser cut from a single metal tube into the desired geometry, creating a tubular scaffold of interconnected struts and crowns that form the openings 2328.

[0348] Since the connector struts 2350 are circumferentially offset from the downstream migration resistance features 2370, the outer frame 2320 has a reduced profile when crimped because stacking of such components is avoided. Further, when crimped, the struts 2330A of the inflow support ring 2376 nest between the connector struts 2350 which results in a shorter overall frame height when crimped. Additionally, the connector struts 2350 exert an outward radial force when under an axial load. More particularly, axial forces directed towards the outflow direction, resulting from blood flow through the prosthesis, cause the connector struts 2350 to exert outward radial forces. The increased radial forces resist migration of the prosthesis.

[0349] With reference to FIG. 23 A-23B, when the dual frame stent structure 2310 is in its radially expanded configuration, the fixation region 2322 of the outer frame 2320 is radially spaced from the inner frame 2340. As such, forces from the native anatomy during operation of the native valve after the transcatheter heart valve prosthesis has been implanted are primarily absorbed by the outer frame 2320 such that the inner frame 2340 and the prosthetic valve component 206 coupled thereto remain substantially undeformed. In other words, the inner frame 2340 and prosthetic valve component 206 are effectively mechanically isolated from the distorting forces exerted on the outer frame 2320 by the native tissue, e g., radially compressive forces exerted by the native annulus and / or leaflets, longitudinal diastolic and systolic forces, hoop stress, etc.

[0350] FIGS. 24A-24B depict a transcatheter heart valve prosthesis 2400 including a dual frame stent structure 2410 according to a fifteenth embodiment hereof. The dual frame stent structure 2410 is the same as the dual frame stent structure 2310, except that an inner frame 2440 of the dual frame stent structure 2410 includes a flared portion 2444 at an inflow or upstream portion thereof. The flared portion 2444 lengthens the inner frame 2440 relative to the inner frame 2340, and thereby lengthens the overall height of the heart valve prosthesis 2400 relative to the overall height of the heart valve prosthesis 2300. However, the flared portion 2444 may also permit the length of connector struts 2450 to be relatively shorter than the length of the connector struts 2350, which may increase the radial strength of the heart valve prosthesis 2400 relative to radial strength of the heart valve prosthesis 2300.

[0351] An outer frame 2420 of the dual frame structure is substantially the same as the outer frame 2340, with the exception that the length of the connector struts 2450 may be relatively shorter than the length of the connector struts 2350. Since the structure of the outer frame 2420 isotherwise the same as the structure of the outer frame 2320, the details thereof are not repeated for sake of brevity.[003521 FIG. 24B illustrates the inner frame 2440 of the dual frame structure 2410 removed from the transcatheter heart valve prosthesis 2400 for sake of illustration only. The inner frame 2440 has the same structure as the inner frame 340 described above, except that the inner frame 2440 is rotated 180 degrees such that the outflow end of the inner frame 340 forms the inflow end of the inner frame 2440. More particularly, the inner frame 2440 includes a cylindrical portion 2442 and a flared portion 2444 extending proximally and radially outward from a proximal or upstream end of the cylindrical portion 2442.

[0353] The inner frame 2440 defines a lumen 2441 from an inflow end 2462 of the inner frame 2440 to an outflow end 2468 of the inner frame 2440. A prosthetic valve component (not shown) is disposed within the lumen 2441 of the inner frame. The cylindrical portion 2442 of the inner frame 2440 has a substantially cylindrical shape which is oriented to extend generally parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 2400. The flared portion 2444 has a first or upstream end defining the inflow end 2462 of the inner frame 2440, as well as the inflow end of the transcatheter heart valve prosthesis 2400. The first or upstream end 2460 of the flared portion 2444 defining the inflow end 2462 of the inner frame 2440 has an outer diameter DI. A second or downstream end of the flared portion 2444 of the inner frame 2440 is integrally formed with or coextensive with a first or upstream end of the cylindrical portion 2442 of the inner frame 2440, and a second or downstream end of the cylindrical portion 2442 defines the outflow end 2468 of the inner frame 2440. The second or downstream end of the cylindrical portion 2442 defining the outflow end 2468 of the inner frame 2440 has an outer diameter D2 that is less than the outer diameter DI. Thus, the flared portion 2444 flares radially, outwardly from the cylindrical portion 2442 such that the flared portion 2444 has a generally frustoconical shape or profile. The outer diameter DI of the inflow end 2462 of the inner frame 2440 is substantially similar to the outer diameter of the inflow end of the outer frame 2420, as the inflow end 2462 of the inner frame 2440 abuts against an inner surface of the outer frame 2420 at the inflow end thereof and is attached to the inflow end of the outer frame 2420 as described with respect to the heart valve prosthesis 2300.

[0354] The inner frame 2440 includes a plurality of openings 2446 that are formed by a plurality of struts 2454 and a plurality of crowns 2452, with each crown 2452 being formedbetween a pair of opposing struts 2454. Each crown 2452 is a curved segment or bend extending between opposing struts 2454. In an embodiment, the inner frame 2440 includes exactly three rows of openings 2446, namely a first row of openings 2446A, a second row of openings 2446B, and a third row of openings 2446C. The first row of openings 2446A is formed at the inflow end 2462 of the inner frame 2440, the third row of openings 2446C is formed at the outflow end 2468 of the inner frame 2440, and the second row of openings 2446B extends between the first and third rows of openings 2446A and 2446C, respectively. In an embodiment, the cylindrical portion 2442 of the inner frame 2440 includes the third row of openings 2446C and the flared portion 2444 of the inner frame 2440 includes the first row of openings 2446A, while the second row of openings 2446B is within both the cylindrical portion 2442 and the flared portion 2444. More particularly, in an embodiment, the two adjacent endmost struts 2454 of the second row of openings 2446B closest to the inflow end 2462 are within the flared portion 2444 of the inner frame.

[0355] In an embodiment, all openings 2446 of the second row of openings 2446B and the third row of openings 2446C are substantially the same size and shape. The openings 2446 of the second row of openings 2446B and the third row of openings 2446C are formed with a shape pattern distinct from a shape pattern of the openings of the first row of openings 2446A. In an embodiment, each opening 2446 of the second row of openings 2446B and the third row of openings 2446C is formed in a hexagonal shape and each opening 246 of the first row of openings 2446A is formed in a diamond shape or a spade shape. The first row of openings 2446A, along with the two adjacent endmost struts 2454 of the second row of openings 2446B closest to the inflow end 2462, do not extend parallel to the longitudinal axis LA of the transcatheter heart valve prosthesis 2400 but rather flares radially outward.

[0356] Embodiments of the present disclosure include the following examples.

[0357] In a first example, a transcatheter heart valve prosthesis comprises: an inner frame including a cylindrical portion and a flared portion extending distally and radially outward from the cylindrical portion, the cylindrical portion defining an inflow end of the inner frame having a first outer diameter and the flared portion defining an outflow end of the inner frame having a second outer diameter that is greater than the first outer diameter, wherein the cylindrical portion is oriented to extend generally parallel to a longitudinal axis of the transcatheter heart valve prosthesis; an outer frame which circumferentially surrounds at least a portion of the inner frame, the outer frame including a fixation region having a third outer diameter that is constant from afirst end of the fixation region to a second end of the fixation region which defines an outflow end of the outer frame, wherein the first end of the fixation region is radially spaced from the inner frame and wherein the second end of the fixation region is attached to the outflow end of the inner frame; and a prosthetic valve component disposed within and attached to the cylindrical portion of the inner frame.

[0358] In a second example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the fixation region has a first height from the first end to the second end thereof and the inner frame has a second height from the inflow end to the outflow end thereof, the second height being between 0 and 250 % longer than the first height.

[0359] In a third example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the fixation region is configured to engage heart tissue at or below a native annulus of a native mitral heart valve.

[0360] In a fourth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the fixation region is oriented to extend generally parallel to the longitudinal axis of the transcatheter heart valve prosthesis.

[0361] In a fifth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the inner frame includes a plurality of endmost outflow crowns, the outer frame includes a plurality of endmost outflow crowns, and a ratio of the endmost outflow crowns of the outer frame to the endmost outflow crowns of the inner frame is 2: 1.

[0362] In a sixth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the flared portion of the inner frame is flared outwardly from a first end to a second end thereof, with the first end of the flared portion having the first outer diameter and the second end of the flared portion, which defines the outflow end of the inner frame, having the second outer diameter.

[0363] In a seventh example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the inner frame includes three rows of openings including a first row of openings within the cylindrical portion, a second row of openings within the cylindrical portion and the flared portion, and a third row of openings within the flared portion.

[0364] In an eighth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the inner frame includes exactly three rows ofopenings including a first row of openings within the cylindrical portion, a second row of openings within the cylindrical portion and the flared portion, and a third row of openings within the flared portion.

[0365] In a ninth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the outflow end of the inner frame includes an outflow ring of struts and crowns, the outflow ring being oriented to extend generally parallel to the longitudinal axis of the transcatheter heart valve prosthesis.

[0366] In a tenth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the openings of the first and second rows are formed via a plurality of struts and a plurality of crowns, and wherein the third row of openings is formed via the outflow ring, endmost struts of the second row of openings, and a plurality of radially - extending segments extending between endmost crowns of the second row of openings and endmost crowns of the outflow ring.

[0367] In an eleventh example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, each opening of the third row of openings is formed by exactly two adjacent struts of the outflow ring, two adjacent endmost struts of the second row of openings, and two adjacent radially extending segments.

[0368] In a twelfth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, each opening of the third row of openings is formed by exactly four adjacent struts of an outflow ring, two adjacent endmost struts of the second row of openings, and two adjacent radially extending segments.

[0369] In a thirteenth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the openings of the first, second, and third rows are formed via a plurality of struts and a plurality of crowns.

[0370] In a fourteenth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, openings of the first and second rows have a first shape and openings of the third row have a second shape that is different from the first shape.

[0371] In a fifteenth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the first shape is a hexagonal shape.

[0372] In a sixteenth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the second shape is a chevron or fluke shape.

[0373] In a seventeenth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the second shape is a diamond or spade shape.

[0374] In an eighteenth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the second shape is a palmate webbed-foot shape.

[0375] In a nineteenth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the fixation region has exactly two rows of openings formed via a plurality of struts and a plurality of crowns.

[0376] In a twentieth example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the fixation region includes at least two rows of cleats, each cleat extending outward from a crown of the fixation region to engage a heart tissue.

[0377] In a twenty-first example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the fixation region includes exactly three rows of cleats.

[0378] In a twenty-second example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, comprises a brim portion extending radially outward from the first end of the fixation region of the outer frame.

[0379] In a twenty-third example, in the transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, the third outer diameter is substantially similar to the second outer diameter.

[0380] In a twenty-fourth example, a transcatheter heart valve prosthesis comprises a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from an undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame, in the deployed state, having at least two rows of openings; and a prosthetic valve component disposed within and attached to the inner frame, wherein the outer frame comprises a plurality of connector struts, wherein each of the plurality of connector struts radially extends from an inflow end of the outer frame and is attached to an outflow end of the inner frame.

[0381] In a twenty-fifth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein one of the at least two rows of openings of the outer frame is a first row of large openings comprising a first pattern shape; and wherein another of the at least two additional rows of openings is a second row of small openings comprising a second pattern shape, wherein the large openings are larger relative to the small openings.

[0382] In a twenty-sixth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the first pattern shape and the second pattern shape are similar shapes.

[0383] In a twenty-seventh example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the first pattern shape is a spade shape.

[0384] In a twenty-eighth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the first pattern shape and the second pattern shape are different shapes.

[0385] In a twenty-ninth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each of the large openings comprises a cleat extending therefrom.

[0386] In a thirtieth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each of the small openings comprises a cleat extending therefrom.

[0387] In a thirty-first example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein an area of the large openings is in the range of 300% to 700% larger than an area of the small openings.

[0388] In a thirty-second example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the plurality of connector struts are arranged such that the outflow end of the inner frame is disposed proximal of an outflow end of the outer frame when the prosthesis is in the deployed state.

[0389] In a thirty-third example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the plurality of connector struts are arranged such that the outflow end of the inner frame is disposed distal to an outflow end of the outer frame when the prosthesis is in the deployed state.

[0390] In a thirty-fourth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each of the connector struts are predominantly straight.

[0391] In a thirty-fifth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each of the connector struts are predominantly straight along their entire length.

[0392] In a thirty-sixth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each opening of the at least two rows of openings of the inner frame are formed in a hexagonal shape.

[0393] In a thirty-seventh example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein exactly two connector struts are attached to each endmost outflow crown on the inner frame.

[0394] In a thirty-eighth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame comprises a flared portion, wherein a diameter of the flared portion increases towards the outflow end.

[0395] In a thirty -ninth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame has a substantially constant diameter along its entire length.

[0396] In a fortieth example, a transcatheter heart valve prosthesis, comprising: a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from undeployed state to a deployed state; the inner frame further comprising a cylindrical portion, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame comprising a cylindrical portion, in the deployed state, having at least two rows of openings; and a prosthetic valve component disposed within and attached to the inner frame, wherein the inner frame further comprises a plurality of first connecting member, each second connecting member extending radially outwards towards the outer frame, wherein the outer frame further comprises a plurality of second connecting members, each first connecting member extending radially inwards towards the inner frame, wherein each of the plurality of first connecting members is attached to a respective second connecting member.

[0397] In a forty-first example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the connection of the plurality of first connecting members and the plurality of second connecting members form a plurality of respective attachment points disposed radially in-between the cylindrical portion of the inner frame and the cylindrical portion of the outer frame.

[0398] In a forty-second example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the plurality of second connecting members are disposed at an inflow end of the outer frame.

[0399] In a forty-third example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the plurality of first connecting members are disposed at a midportion of the inner frame.

[0400] In a forty-fourth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein a portion of the inner frame disposed downstream of the first connecting members comprises an uncovered portion.

[0401] In a forty-fifth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the plurality of second connecting members are disposed at an outflow end of the outer frame.

[0402] In a forty-sixth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the plurality of first connecting members are disposed at an outflow end of the inner frame.

[0403] In a forty-seventh example, a transcatheter heart valve prosthesis, comprising: a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, in the deployed state, comprising at least two rows of openings including a first row of openings at an outflow end of the outer frame, and a prosthetic valve component disposed within and attached to the inner frame, wherein at least the first row of openings comprises a first pattern shape for each of its openings, wherein the first pattern shape is partially formed by a pair of axial struts which extend along a longitudinal axis, and a pair of strutsforming a chevron, the chevron extending between the pair of axial struts, wherein the chevron is configured to flare radially outward from the outflow end of the outer frame.

[0404] In a forty-eighth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each chevron comprises a cleat at a tip of the chevron.

[0405] In a forty-ninth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein at least two of the rows of openings comprises the first pattern shape for each of its openings.

[0406] In a fiftieth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein all of the rows of openings comprise the first pattern shape for each of their openings.

[0407] In a fifty-first example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the first pattern shape comprises a second pair of struts connected to the pair of struts, forming a double chevron extending between the pair of axial struts.

[0408] In a fifty-second example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the rest of the several rows of openings comprises a second pattern shape for each of its openings.

[0409] In a fifty-third example, a transcatheter heart valve prosthesis, comprising a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from an undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame, in the deployed state, having at least a first row of openings and a second row of openings, the second row of openings being closer to an outflow end of the outer frame; and a prosthetic valve component disposed within and attached to the inner frame, wherein the outer frame comprises a plurality of connector struts, wherein each of the plurality of connector struts radially extends from a midportion of the outer frame and is attached to an outflow end of the inner frame, and wherein the second row of openings includes a plurality of hanging fixation cells that are longitudinally aligned and radially outwardly offset from the plurality of connectorstruts, the hanging fixation cells being disconnected from, and not directly attached to, the outflow end of the inner frame.

[0410] In a fifty -fourth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the inner frame is substantially cylindrical along its length and the outer frame comprises a tapered portion, wherein a diameter of the tapered portion decreases towards the outflow end thereof.

[0411] In a fifty -fifth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein a fixation region of the outer frame includes exactly three rows of openings including the first row of openings, the second row of openings, and an intermediate row of openings disposed between the first and second rows of openings, and wherein a cylindrical portion of the outer frame includes the first row of openings and a tapered portion of the outer frame includes the second row of openings, while the intermediate row of openings is within both the cylindrical portion and the tapered portion.

[0412] In a fifty-sixth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein all openings of the first row of openings, the second row of openings, and the intermediate row of openings are substantially the same shape.

[0413] In a fifty-seventh example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the shape is a diamond or a hexagonal shape.

[0414] In a fifty-eighth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame further includes an outflow support ring having a plurality of struts and a plurality of crowns, each crown being formed between a pair of struts, and wherein a first set of the plurality of crowns are attached to the connector struts and a second set of the plurality of crowns are attached to the hanging fixation cells.

[0415] In a fifty -ninth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the first set of the plurality of crowns are spaced radially inwards relative to the second set of the plurality of crowns.

[0416] In a sixtieth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each hanging fixation cell of the plurality ofhanging fixation cells includes a cleat extending radially outwards and / or upstream from an outer surface of the outer frame.

[0417] In a sixty-first example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the plurality of hanging fixation cells form an uncovered portion of the outer frame that does not receive a sealing component.

[0418] In a sixty-second example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each connector strut of the plurality of connector struts is substantially straight.

[0419] In a sixty-second example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the plurality of connector struts are integrally formed with the outer frame.

[0420] In a sixty-third example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each connector strut of the plurality of connector struts is circumferentially disposed between a pair of adjacent hanging fixation cells of the plurality of hanging fixation cells.

[0421] In a sixty-fourth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame includes exactly two rows of openings including the first row of openings and the second row of openings, and wherein a cylindrical portion of the outer frame includes the first row of openings and the second row of openings is within the cylindrical portion and a tapered portion of the outer frame.

[0422] In a sixty-fifth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each opening of the first row of openings is formed in a diamond or hexagonal shape, and each opening of the first row of openings is the same size.

[0423] In a sixty-sixth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the second row of openings includes first openings and second openings formed in a diamond or hexagonal shape, with the first openings being relatively larger than the second openings, and wherein the first openings form the hanging fixation cells of the outer frame.

[0424] In a sixty-seventh example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each hanging fixation cell of the pluralityof hanging fixation cells includes a cleat extending radially outwards and / or upstream from an outer surface of the outer frame.

[0425] In a sixty-eighth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame includes exactly three hanging fixation cells.

[0426] In a sixty-ninth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the exactly three hanging fixation cells are circumferentially spaced apart around a circumference of the outer frame at approximately equally spaced intervals.

[0427] In a seventieth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame further includes an outflow support ring having a plurality of struts and a plurality of crowns, each crown being formed between a pair of struts, and wherein the outflow support ring is attached to and extends distally from outflow ends of the connector struts.

[0428] In a seventy -first example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame includes at least two rows of cleats that extend upstream and / or radially outward from an outer surface of the outer frame.

[0429] In a seventy-second example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame includes exactly one row of barbs that extend upstream and / or radially outward from an outer surface of the outer frame, each barb having a v-shaped configuration with a first leg, a second leg, and an apex formed between the first and second legs, and wherein the apex of each barb is radially spaced apart from the outer surface of the outer frame when deployed.

[0430] In a seventy-third example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each barb is configured to extend substantially transverse to blood flow when deployed.

[0431] In a seventy-fourth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame further includes at least one row of cleats that extend upstream and / or radially outward from an outer surface of the outer frame.

[0432] In a seventy -fifth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame further includes exactly two row of cleats that extend upstream and / or radially outward from an outer surface of the outer frame.

[0433] In a seventy-sixth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the at least one row of cleats is disposed upstream of the one row of barbs.

[0434] In a seventy -seventh example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each barb of the one row of barbs is longer than each cleat of the at least one row of cleats.

[0435] In a seventy-eighth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein a length of each barb of the one row of barbs is at least twice a length of each cleat of the at least one row of cleats.

[0436] In a seventy-ninth example, a transcatheter heart valve prosthesis includes a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from an undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame, in the deployed state, having at least a first row of openings and a second row of openings, the first row of openings being closer to an inflow end of the outer frame; and a prosthetic valve component disposed within and attached to the inner frame, wherein the first row of openings includes a plurality of flared cells and a plurality of tapered cells, with each flared cell of the plurality of flared cells being disposed between a pair of adjacent tapered cells of the plurality of tapered cells and each tapered opening of the plurality of tapered cells being disposed between a pair of adjacent flared cells of the plurality of flared cells, and wherein the outer frame comprises a plurality of connector struts, each connector strut of the plurality of connector struts radially extending from an inflow end of a tapered cell of the plurality of tapered cells to an inflow end of the inner frame, and wherein the outer frame comprises a plurality of downstream-extending cleats, each downstream-extending cleat extending from an inflow end of a flared cell of the plurality of flared cells towards an outflow end of the outer frame.

[0437] In an eightieth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the inner frame is substantially cylindrical along its length and the outer frame comprises a tapered portion at an inflow end of the outer frame.

[0438] In an eighty-first example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the inner frame comprises a flared portion at an inflow end of the inner frame and the outer frame comprises a tapered portion at an inflow end of the outer frame.

[0439] In an eighty-second example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame further includes an inflow support ring at an inflow end of the outer frame, the inflow support ring having a plurality of struts and a plurality of crowns, each crown being formed between a pair of struts.

[0440] In an eighty -third example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame further comprises a plurality of upstream-extending cleats, and wherein each opening of the second row of openings includes an upstream-extending cleat of the plurality of upstream-extending cleats, each upstreamextending cleat extending radially outwards and towards an inflow end of the outer frame.

[0441] In an eighty -fourth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame further includes a third row of openings disposed between the first row of openings and the second row of openings and wherein each opening of the third row of openings includes an upstream-extending cleat of the plurality of upstream-extending cleats.

[0442] In an eighty-fifth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each flared cell of the plurality of flared cells includes an upstream-extending cleat of the plurality of upstream-extending cleats and each tapered cell of the plurality of tapered cells includes an upstream-extending cleat of the plurality of upstream-extending cleats.

[0443] In an eighty-sixth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each connector strut of the plurality of connector struts is substantially straight.

[0444] In an eighty-seventh example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the plurality of connector struts are integrally formed with the outer frame.

[0445] In an eighty-eighth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each flared cell of the plurality of flared cells includes four struts, two adjacent endmost struts of the four struts which are closest to an outflow end of the outer frame being oriented substantially parallel to a longitudinal axis of the transcatheter heart valve prosthesis and two adjacent endmost struts of the four struts which are closest to an inflow end of the outer frame being oriented to extend radially outwards relative to the longitudinal axis of the transcatheter heart valve prosthesis.

[0446] In an eighty-ninth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein a downstream half of each flared cell of the plurality of flared cells is oriented substantially parallel to a longitudinal axis of the transcatheter heart valve prosthesis while an upstream half of each flared cell of the plurality of flared cells is oriented to extend radially outwards relative to the longitudinal axis of the transcatheter heart valve prosthesis.

[0447] In a ninetieth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein each tapered cell of the plurality of tapered cells includes four struts, two adjacent endmost struts of the four struts which are closest to an outflow end of the outer frame being oriented substantially parallel to a longitudinal axis of the transcatheter heart valve prosthesis and two adjacent endmost struts of the four struts which are closest to an inflow end of the outer frame being oriented to extend radially inwards relative to the longitudinal axis of the transcatheter heart valve prosthesis.

[0448] In a ninety-first example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein a downstream half of each tapered cell of the plurality of tapered cells is oriented substantially parallel to a longitudinal axis of the transcatheter heart valve prosthesis while an upstream half of each tapered cell of the plurality of tapered cells is oriented to extend radially inwards relative to the longitudinal axis of the transcatheter heart valve prosthesis.

[0449] In a ninety-second example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the plurality of connector struts extend atan angle relative to a longitudinal axis of the transcatheter heart valve prosthesis to form a tapered portion of the outer frame, the angle being between 50° and 80° relative to the longitudinal axis.

[0450] In a ninety -third example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame includes a total of twelve connector struts, twelve tapered cells and twelve flared cells.

[0451] In a ninety-fourth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame has a flared portion at an outflow end thereof, wherein the diameter of the flared portion increases towards the outflow end of the outer frame.

[0452] In a ninety-fifth example, a transcatheter heart valve prosthesis according to any of the previous or subsequent examples herein, wherein the outer frame comprises a tapered portion at an inflow end thereof, wherein the diameter of the tapered portion decreases towards the inflow end of the outer frame.

[0453] The foregoing description has been presented for purposes of illustration and enablement and is not intended to be exhaustive or to limit the invention to the precise form disclosed. Other modifications and variations are possible in light of the above teachings. The embodiments and examples were chosen and described in order to best explain the principles of the invention and its practical application and to thereby enable others skilled in the art to best utilize the invention in various embodiments and various modifications as are suited to the particular use contemplated. It is intended that the appended claims be construed to include other alternative embodiments of the invention.

Claims

CLAIMS1. A transcatheter heart valve prosthesis, comprising: an inner frame including a cylindrical portion and a flared portion extending distally and radially outward from the cylindrical portion, the cylindrical portion defining an inflow end of the inner frame having a first outer diameter and the flared portion defining an outflow end of the inner frame having a second outer diameter that is greater than the first outer diameter, wherein the cylindrical portion is oriented to extend generally parallel to a longitudinal axis of the transcatheter heart valve prosthesis; an outer frame which circumferentially surrounds at least a portion of the inner frame, the outer frame including a fixation region having a third outer diameter that is constant from a first end of the fixation region to a second end of the fixation region which defines an outflow end of the outer frame, wherein the first end of the fixation region is radially spaced from the inner frame and wherein the second end of the fixation region is attached to the outflow end of the inner frame; and a prosthetic valve component disposed within and attached to the cylindrical portion of the inner frame.

2. The transcatheter heart valve prosthesis of claim 1, wherein the fixation region has a first height from the first end to the second end thereof and the inner frame has a second height from the inflow end to the outflow end thereof, the second height being between 0 and 250 % longer than the first height.

3. The transcatheter heart valve prosthesis of claim 1, wherein the inner frame includes a plurality of endmost outflow crowns, the outer frame includes a plurality of endmost outflow crowns, and a ratio of the endmost outflow crowns of the outer frame to the endmost outflow crowns of the inner frame is 2: 1.

4. The transcatheter heart valve prosthesis of claim 1, wherein the inner frame includes three rows of openings including a first row of openings within the cylindrical portion, a second row of openings within the cylindrical portion and the flared portion, and a third row of openings within the flared portion.

5. The transcatheter heart valve prosthesis of claim 4, wherein the outflow end of the inner frame includes an outflow ring of struts and crowns, the outflow ring being oriented to extend generally parallel to the longitudinal axis of the transcatheter heart valve prosthesis.

6. The transcatheter heart valve prosthesis of claim 5, wherein the openings of the first and second rows are formed via a plurality of struts and a plurality of crowns, and wherein the third row of openings is formed via the outflow ring, endmost struts of the second row of openings, and a plurality of radially-extending segments extending between endmost crowns of the second row of openings and endmost crowns of the outflow ring.

7. The transcatheter heart valve prosthesis of claim 6, wherein each opening of the third row of openings is formed by exactly two adjacent struts of the outflow ring, two adjacent endmost struts of the second row of openings, and two adjacent radially extending segments.

8. The transcatheter heart valve prosthesis of claim 4, wherein each opening of the third row of openings is formed by exactly four adjacent struts of an outflow ring, two adjacent endmost struts of the second row of openings, and two adjacent radially extending segments.

9. The transcatheter heart valve prosthesis of claim 4, wherein the openings of the first, second, and third rows are formed via a plurality of struts and a plurality of crowns.

10. The transcatheter heart valve prosthesis of claim 4, wherein openings of the first and second rows have a first shape and openings of the third row have a second shape that is different from the first shape.

11. The transcatheter heart valve prosthesis of claim 10, wherein the first shape is a hexagonal shape and the second shape is a chevron or fluke shape.

12. The transcatheter heart valve prosthesis of claim 10, wherein the first shape is a hexagonal shape and the second shape is a diamond or spade shape.

13. The transcatheter heart valve prosthesis of claim 10, wherein the first shape is a hexagonal shape and the second shape is a palmate webbed-foot shape.

14. The transcatheter heart valve prosthesis of claim 1 , wherein the fixation region has exactly two rows of openings formed via a plurality of struts and a plurality of crowns.

15. The transcatheter heart valve prosthesis of claim 1, wherein the fixation region includes at least two rows of cleats, each cleat extending outward from a crown of the fixation region to engage a heart tissue.

16. A transcatheter heart valve prosthesis, comprising: a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from an undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame, in the deployed state, having at least two rows of openings; and a prosthetic valve component disposed within and attached to the inner frame, wherein the outer frame comprises a plurality of connecting struts, wherein each of the plurality of connecting struts radially extends from an inflow end of the outer frame and is attached to an outflow end of the inner frame.

17. The transcatheter heart valve prosthesis of claim 16, wherein one of the at least two rows of openings of the outer frame is a first row of large openings comprising a first pattern shape; and wherein another of the at least two rows of openings is a second row of small openings comprising a second pattern shape, wherein the large openings are larger relative to the small openings, and wherein an area of the large openings is in the range of 300% to 700% larger than an area of the small openings.

18. The transcatheter heart valve prosthesis of claim 16, wherein exactly two connecting struts are attached to each endmost outflow crown on the inner frame.

19. A transcatheter heart valve prosthesis, comprising: a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from undeployed state to a deployed state; the inner frame further comprising a cylindrical portion, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame comprising a cylindrical portion, in the deployed state, having at least two rows of openings; and a prosthetic valve component disposed within and attached to the inner frame, wherein the inner frame further comprises a plurality of first connecting member, each first connecting member extending radially outwards towards the outer frame, wherein the outer frame further comprises a plurality of second connecting members, each second connecting member extending radially inwards towards the inner frame, wherein each of the plurality of first connecting members is attached to a respective second connecting member.

20. The transcatheter heart valve prosthesis of claim 19, wherein the connection of the plurality of first connecting members and the plurality of second connecting members form a plurality of respective attachment points disposed radially in-between the cylindrical portion of the inner frame and the cylindrical portion of the outer frame.

21. The transcatheter heart valve prosthesis of claim 19, wherein the plurality of second connecting members are disposed at an inflow end of the outer frame.

22. The transcatheter heart valve prosthesis of claim 21, wherein the plurality of first connecting members are disposed at a midportion of the inner frame.

23. The transcatheter heart valve prosthesis of claim 19, wherein a portion of the inner frame disposed downstream of the first connecting members comprises an uncovered portion.

24. The transcatheter heart valve prosthesis of claim 19, wherein the plurality of second connecting members are disposed at an outflow end of the outer frame.

25. The transcatheter heart valve prosthesis of claim 24, wherein the plurality of first connecting members are disposed at an outflow end of the inner frame.

26. A transcatheter heart valve prosthesis, comprising: a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from an undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame, in the deployed state, having at least a first row of openings and a second row of openings, the second row of openings being closer to an outflow end of the outer frame; and a prosthetic valve component disposed within and attached to the inner frame, wherein the outer frame comprises a plurality of connector struts, wherein each of the plurality of connector struts radially extends from a midportion of the outer frame and is attached to an outflow end of the inner frame, and wherein the second row of openings includes a plurality of hanging fixation cells that are longitudinally aligned and radially outwardly offset from the plurality of connector struts, the hanging fixation cells being disconnected from, and not directly attached to, the outflow end of the inner frame.

27. The transcatheter heart valve prosthesis of claim 26, wherein the outer frame further includes an outflow support ring having a plurality of struts and a plurality of crowns, each crown being formed between a pair of struts, and wherein a first set of the plurality of crowns are attached to the connector struts and a second set of the plurality of crowns are attached to the hanging fixationcells, and wherein the first set of the plurality of crowns are spaced radially inwards relative to the second set of the plurality of crowns.

28. The transcatheter heart valve prosthesis of claim 26, wherein each hanging fixation cell of the plurality of hanging fixation cells includes a cleat extending radially outwards and / or upstream from an outer surface of the outer frame.

29. The transcatheter heart valve prosthesis of claim 26, wherein the plurality of hanging fixation cells form an uncovered portion of the outer frame that does not receive a sealing component.

30. The transcatheter heart valve prosthesis of claim 26, wherein each connector strut of the plurality of connector struts is circumferentially disposed between a pair of adjacent hanging fixation cells of the plurality of hanging fixation cells.

31. The transcatheter heart valve prosthesis of claim 26, wherein the outer frame includes exactly two rows of openings including the first row of openings and the second row of openings, and wherein a cylindrical portion of the outer frame includes the first row of openings and the second row of openings is within the cylindrical portion and a tapered portion of the outer frame.

32. The transcatheter heart valve prosthesis of claim 31, wherein the second row of openings includes first openings and second openings formed in a diamond or hexagonal shape, with the first openings being relatively larger than the second openings, and wherein the first openings form the hanging fixation cells of the outer frame.

33. The transcatheter heart valve prosthesis of claim 32, wherein the outer frame includes exactly three hanging fixation cells which are circumferentially spaced apart around a circumference of the outer frame at approximately equally spaced intervals.

34. A transcatheter heart valve prosthesis, comprising:a stent structure for maintaining structural integrity of the transcatheter heart valve prosthesis, the stent structure comprising an inner frame and an outer frame, the stent structure configured to radially expand from an undeployed state to a deployed state; the inner frame, in the deployed state, having at least two rows of openings; the outer frame circumferentially surrounding at least a portion of the inner frame, the outer frame, in the deployed state, having at least a first row of openings and a second row of openings, the first row of openings being closer to an inflow end of the outer frame; and a prosthetic valve component disposed within and attached to the inner frame, wherein the first row of openings includes a plurality of flared cells and a plurality of tapered cells, with each flared cell of the plurality of flared cells being disposed between a pair of adjacent tapered cells of the plurality of tapered cells and each tapered opening of the plurality of tapered cells being disposed between a pair of adjacent flared cells of the plurality of flared cells, and wherein the outer frame comprises a plurality of connector struts, each connector strut of the plurality of connector struts radially extending from an inflow end of a tapered cell of the plurality of tapered cells to an inflow end of the inner frame, and wherein the outer frame comprises a plurality of downstream-extending cleats, each downstream-extending cleat extending from an inflow end of a flared cell of the plurality of flared cells towards an outflow end of the outer frame.

35. The transcatheter heart valve prosthesis of claim 34, wherein the outer frame further comprises a plurality of upstream-extending cleats, and wherein each opening of the second row of openings includes an upstream-extending cleat of the plurality of upstream-extending cleats, each upstreamextending cleat extending radially outwards and towards an inflow end of the outer frame.Ill

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