Prosthetic heart valve with elastic support structure and related methods

Abstract

Describes a prosthetic heart valve having resilient leaflets and a resilient support structure. The support structure may exhibit a lead transition from a closed position to an open position. The support structure may exhibit a sinusoidal movement profile at the base edge during the lead transition.

Description

Technical Field

[0001] The subject matter described herein relates to prosthetic heart valves, and more particularly, to prosthetic heart valves having a support structure that stores energy and effectively assists in the opening and closing of leaflets. Background Art

[0002] The human heart has many valves that serve to maintain blood flow through the body in the correct direction. The main valves of the heart are the atrioventricular (AV) valves (including the mitral (bicuspid) valve and the tricuspid valve) and the semilunar valves (including the aortic valve and the pulmonary valve). In a healthy condition, each of these valves operates in a similar manner. In response to a pressure differential induced across the valve, the valve transitions between an open state (permitting blood flow) and a closed state (preventing blood flow).

[0003] If any of these valves begins to malfunction, the health of the patient can be at serious risk. While malfunction can be caused by a variety of reasons, malfunction typically results in restricted or stenotic blood flow or regurgitation, in which case blood is permitted to flow in the wrong direction. If the defect is severe, the heart valve may need to be replaced.

[0004] Considerable effort has been devoted to the development of replacement heart valves (most notably, replacement aortic valves and replacement mitral valves). Replacement valves can be implanted percutaneously via a catheter introduced through the femoral or apical route, or can be implanted directly through a thoracotomy. Replacement valves typically include an arrangement of valve leaflets made from porcine tissue. These tissue leaflets can be highly inflated or stretched. Other replacement valves have been proposed in which the leaflets are artificial polymer structures. In both cases, the leaflets are typically held in place by a stent or support structure that has a relatively high stiffness (in the case of a surgically implanted replacement valve) or expands into a highly rigid state or can be fixed in a highly rigid state (in the case of a transcatheter valve), thereby providing maximum support for the leaflets. However, these highly rigid support structures are generally passive structures that provide little, if any, positive benefit to the operation of the valve itself in controlling flow other than support.

[0005] For these and other reasons, there is a need for improved prosthetic valves. Summary of the Invention

[0006] Provided herein are many exemplary embodiments of a prosthetic heart valve having two or more individual leaflets and a synthetic resilient support structure. In many exemplary embodiments, the leaflets can have a stiffness sufficient to transfer a load to the resilient support structure during closure. The support structure is of an elastic nature such that it allows the support structure to store the transferred load as potential energy and then release it in the form of kinetic energy at an appropriate time to assist the leaflets in moving from a closed state to an open state. In many embodiments, this transition caused by the support structure is antecedent and occurs without leaflet assistance. This antecedent transition to the open state can result in a pressure wave that is very similar to the pressure wave of a healthy native human heart valve. Exemplary embodiments of related methods of use and manufacture of the prosthetic valve are also described.

[0007] When reviewing the following drawings and detailed description, other systems, devices, methods, features, and advantages of the subject matter described herein will be or will become apparent to those of ordinary skill in the art. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the subject matter described herein, and be protected by the accompanying claims. The features of the exemplary embodiments should in no way be construed as limiting the appended claims, where there is no explicit recitation of those features in the claims. Brief Description of the Drawings

[0008] By studying the drawings, details (both of its structure and operation) of the subject matter set forth herein may be apparent, in which like reference numerals refer to like parts. The components in the drawings are not necessarily drawn to scale, but rather emphasis is placed on illustrating the principles of the subject matter. Additionally, all illustrations are intended to convey concepts, where relative sizes, shapes, and other detailed attributes may be illustrated schematically (rather than precisely or explicitly).

[0009] Figure 1A-1B are a perspective view and a top view, respectively, depicting an exemplary embodiment of a prosthetic heart valve in a neutral position.

[0010] Figure 2A-2C are a perspective view, a top view, and a side view, respectively, depicting an exemplary embodiment of a prosthetic heart valve in an open position.

[0011] Figure 3A-3C are a perspective view, a top view, and a side view, respectively, depicting an exemplary embodiment of a prosthetic heart valve in a closed position.

[0012] Figure 4A is a graph showing an example of an idealized pressure across the valve over time.

[0013] Figure 4BA graph showing the potential and kinetic energy of an exemplary embodiment of a support structure over time.

[0014] Figure 5A-5B A partial side view and a perspective view of an exemplary embodiment of a prosthetic heart valve with an instantaneous velocity vector induced during the transition to an open position, respectively. Detailed Description

[0015] Before describing the subject matter in detail, it will be understood that the present disclosure is not limited to the specific embodiments described, and thus can of course vary. It will also be understood that the terms used herein are for the purpose of describing specific embodiments only and are not intended to be limiting, as the scope of the present disclosure will be limited only by the appended claims.

[0016] Exemplary embodiments of systems, devices, kits, and methods related to valve replacement in human or animal subjects are provided herein. For ease of description, these embodiments of the prosthetic heart valve are tricuspid valves that can be implanted via a thoracotomy and are thus not compressible and expandable for transcatheter delivery.

[0017] However, the subject matter is not limited to such embodiments, and the subject matter can be applied to heart valves that can be implanted transcatheter, which have a first radially compressed state for encapsulation within a tubular catheter and delivery distally from the opening of the catheter and a second radially expanded state for normal operation within the heart. Similarly, whether implanted via a thoracotomy or via transcatheter delivery, the subject matter can be applied to prosthetic heart valves having only two leaflets or having more than three leaflets. These prosthetics can also be used to replace valves in other locations outside the heart in a patient's body.

[0018] Figure 1A is a perspective view of an exemplary embodiment of a prosthetic heart valve 100, and Figure 1B is a top view of an exemplary embodiment of a prosthetic heart valve 100. The support structure 102 is coupled to a plurality of valve leaflets 110-1, 110-2, and 110-3. Each leaflet 110 can be discrete relative to the other leaflets 110 (as shown herein), or can be part of a one-piece leaflet body.

[0019] When the valve 100 is implanted, the valve 100 is configured to allow or permit blood to flow in the direction indicated herein along the central axis 101, which extends through the interior of the valve 100. Blood can flow from the upstream (blood inlet) end 103 of the valve toward the downstream (blood outlet) end 104, but the presence of the leaflets 110 prevents (or substantially prevents) blood from flowing in the opposite direction.

[0020] The support structure 102 (which may also be referred to as a frame) includes an annular base portion 105 that may have a planar or flat upstream edge (or surface) 120 in a neutral position, or may have a curved or scalloped upstream edge (not shown) in a neutral position. In U.S. Patent No. 9,301,837, an example of a valve with a scalloped upstream edge is depicted and described, and that patent is incorporated herein by reference in its entirety and for all purposes. Here, the upstream edge 120 is also the terminus of the valve 100 and is disposed along a single flange 121 that extends radially outward from the sidewall of the valve 100. In other embodiments, the flange 121 may be located at a more downstream position on the valve 100 such that the flange 121 is not co-located with the upstream edge 120. The flange 121 can be used to attach a suture cuff to the exterior of the support structure 102. Those of ordinary skill in the art will readily understand the design and appearance of the suture cuff and how the suture cuff can be coupled to the support structure 102. Although multiple flanges 121 may be included, preferably only a single flange 121 is used to enhance the flexibility of the base 105.

[0021] The support structure 102 further includes three projecting structures 106-1, 106-2, and 106-3, which may be referred to herein as projections or extensions. The projections 106 project from the annular base portion 105 toward the downstream end 104, and one projection 106 is present between each pair of adjacent leaflets 110 such that the leaflets 110 and the projections 106 are arranged in an alternating manner around the valve 100. In an embodiment having only two leaflets 110, there will be only two projections 106. Each projection 106 tapers to a downstream end 107. Here, each downstream end 107 is also the apex or terminus of the projection 106.

[0022] The support structure 102 includes a curved interface 108, which is the location where the support structure 102 abuts the base of the leaflets 110. The base of each leaflet 110 may be a physical edge such as would exist if the leaflets 110 and the support structure 102 were manufactured separately and then later joined together. In the embodiments described herein, such as where the valve 100 is made of synthetic or artificial (i.e., non-tissue) leaflets 110, for example, using various casting (e.g., dip casting, etc.) and molding procedures to form the support structure 102 and the leaflets 110 in an integral or semi-integral manner, the curved interface 108 may define a seamless or uninterrupted boundary between the support structure 102 and the leaflets 110. Exemplary embodiments of methods for manufacturing the valve 100 are described elsewhere herein.

[0023] During operation, the valve 100 moves cyclically between an open position that permits blood flow through the interior of the valve and a closed position where the leaflets 110 prevent blood flow through the interior of the valve. Each of these leaflets 110 has a free edge 111 that moves radially inward (toward the closed position) and radially outward (toward the open position). Each leaflet 110 also has an upstream end (or most upstream portion) 112, which in this embodiment is also the upstream tip or end of the leaflet 110.

[0024] Figure 1A and Figure 1B depict the valve 100 with the leaflets 110 in a neutral position, such as may be presented during casting or other shaping of the valve 100. The neutral position is the same as or similar to the rest position of the valve 100. Figure 2A-2C are a perspective view, a top view, and a side view, respectively, depicting an exemplary embodiment of the valve 100 in the open position. Here, specifically visible in the Figure 2B top view, the free edges 111 of the leaflets 110 have moved radially outward from the central axis 101 and a relatively large opening has been formed to permit blood flow. As will be discussed further herein, the movement of the leaflets 110 toward this open position is due not only to the pressure exerted by the blood but also to the active movement of the support structure 102 earlier in the cycle.

[0025] Figure 3A-3C are a perspective view, a top view, and a side view, respectively, depicting an exemplary embodiment of the valve 100 in the closed position, where the protrusions 106 (e.g., ends 107) are closer to each other radially than in the open position. Here, the free edges 111 of the leaflets 110 have moved radially inward toward the central axis 101 (not shown) and are in contact with each other. In other words, free edge 111-1 is in contact with free edges 111-2 and 111-3, free edge 111-2 is in contact with free edges 111-1 and 111-3, and free edge 111-3 is in contact with free edges 111-1 and 111-2. This position is referred to herein as the engaged state of the leaflets 110. In this state, blood flow in the opposite incorrect direction (i.e., from downstream to upstream) is (at least substantially) prevented. As described in the incorporated U.S. Patent No. 9,301,837, certain embodiments of the valve 100 may be configured with a convex leaflet support structure interface.

[0026] One of ordinary skill in the art will appreciate that although the leaflets in the engaged state (or fully engaged state) that prevents blood flow are referred to, this does not require absolute engagement nor absolute prevention of blood flow, because there may be limited situations where when the valve 100 is in the closed position, there are very small and negligible gaps between the leaflets. Thus, when the valve 100 is in the closed position, at least most of the free edges 112 will contact each other, and in many embodiments, all of the free edges 112 will contact each other. Additionally, within a short time interval just prior to full engagement, the leaflet edges may begin to touch without being fully engaged. Such a state may be referred to as "partially engaged". Within a short time interval after the leaflets have disengaged from the fully engaged state and transitioned to the open state, the leaflets may similarly be in a partially engaged state.

[0027] Figure 4A is a graph that depicts an exemplary representation of the idealized across-valve blood (or other fluid in a test, for example) pressure across the leaflets 110 during a portion of the cardiac cycle. This graph shows a simulation or model of the across-valve pressure for a mitral valve and will be described in that context, but the pressure illustrated by this graph may also apply to an aortic valve. For a mitral valve, the across-valve pressure is generally the pressure in the left atrium minus the pressure in the left ventricle. For an aortic valve, the across-valve pressure is generally the pressure in the aorta minus the pressure in the left ventricle.

[0028] Region 402 indicates the period when there is a positive pressure across the leaflets 110 and generally corresponds to the period when the mitral valve is open (the leaflets 110 are not engaged). In region 402, the left ventricle is in diastole and the left atrium contracts to further fill the left ventricle with blood. This period is typically relatively long but has been compressed here for ease of illustration. Region 402 extends to point A where the across-valve pressure transitions from a positive number to zero and blood stops moving in the correct upstream-to-downstream direction (from the left atrium to the left ventricle).

[0029] Region 404 generally indicates the period starting at point A when the across-valve pressure is zero and then becomes negative and continues to decrease (becomes more negative). When negative, the blood is pressured to move in the opposite direction (from downstream to upstream). As the pressure transitions from zero to negative, the mitral valve begins to close. Region 404 terminates at point B which indicates the time point when the peak negative pressure is exhibited across the leaflets 110. In region 404, the aortic valve opens and the left ventricle undergoes isovolumetric contraction.

[0030] Region 406 generally indicates the period from point B to point C during which the peak negative pressure remains generally constant. At point B, the mitral valve leaflets are fully engaged. Those skilled in the art will recognize that, since Figure 4A is an idealized graph of the pressure across the valve, the pressure trajectories in regions 402 - 410 have generally constant slopes (or no slope as in the case of region 404). In an actual heart, these pressures across the valve will exhibit greater variation, as would be expected in a complex natural environment. Thus, the pressures in region 406 and others will vary in actual practice, and region 406 can be regarded as a transition region where the blood pressure exhibits discrete peaks or a peak curve before becoming more negative.

[0031] Region 408 indicates the period beginning at point C during which the pressure steadily increases (becomes less negative) until it reaches zero at point D. In region 408, the left ventricle undergoes isovolumic relaxation, the aortic valve closes, and the native mitral valve remains closed.

[0032] Region 410 generally indicates the period beginning at point D during which the pressure increases from zero and becomes more positive. When positive, the blood is pressured to move in the correct direction (from upstream to downstream). As the pressure transitions from zero to positive, the native mitral valve begins to disengage. Region 410 generally corresponds to the start of a new cardiac cycle and is essentially a repetition of region 402.

[0033] Figure 4B is a graph depicting how the potential energy and kinetic energy of the support structure 102 itself vary with time during the idealized pressure cycle across the valve in Figure 4A . The potential energy is indicated by the trajectory 420, and the kinetic energy is indicated by the trajectory 440. The positions of points A - D from Figure 4A are indicated along the time scale.

[0034] Figure 4B depicts the characteristics of some exemplary embodiments of the valve 100, where as the artificial leaflets 110 move radially inward toward the engaged state, the artificial leaflets 110 transfer or unload the load to the elastic support structure 102, which then stores the transferred load as potential energy. Tissue (i.e., non - artificial) leaflets may over - expand and not transfer the load in the same way. The potential energy stored in the support structure 102 when in the closed position can then be released in the form of kinetic energy (such as when the pressure across the valve becomes less negative).

[0035] Embodiments of the support structure 102 are thus able to move from the closed position toward the open position long before the pressure across the valve becomes positive, as is the case with a native valve. This may be referred to as a "springback" or "active springback" property of the support structure 102, wherein the support structure 102 rebounds from the closed position back to the open position before the pressure across the valve becomes positive (or "early" compared to a native valve), and in many cases, well before the pressure across the valve becomes positive (before normal blood flow). Thus, the anticipatory transition occurs without the support structure initiating movement due to the leaflets (e.g., the support structure being pulled or dragged by the leaflets), and without the support structure being initially forced open due to positive back pressure or the flow of blood through the valve.

[0036] exist Figure 4B In region 402, the potential energy 420 and kinetic energy 440 of the support structure 102 are substantially minimal, while the pressure across the valve is in region 402. As the pressure across the valve transitions from zero in region 404 and becomes more negative, the potential energy 420 begins to increase in a manner comparable to the pressure decrease ( Figure 4A ) increases with a slope that is comparable but opposite to that of the support structure 102. As the pressure becomes more negative, the leaflets 110 experience a higher load from the fluid and accelerate radially inward toward the location of engagement. The increase in potential energy 420 in region 404 is primarily due to the transfer or removal of this load from the leaflets 110 to the support structure 102, which stores the potential energy in the form of elastic deformation of the material body of the support structure 102.

[0037] As the pressure across the valve becomes more negative from zero in region 404, kinetic energy 440 exhibits a peak 442 corresponding to the initial rapid movement of support structure 102 from the open position toward the closed position. At 444, as support structure 102 elastically deforms toward the closed position, potential energy 420 increases from zero, and kinetic energy 440 decreases at a non-constant decreasing rate.

[0038] At point B, leaflets 110 touch and enter a fully coapted state. This corresponds to a sharp drop 446 in kinetic energy 440, indicating that support structure 102 has substantially reached the closed position. As support structure 102 settles into the closed position, there continues to be some decrease in kinetic energy to point C in region 406. Potential energy 420 has reached its maximum value in region 406 and remains substantially constant, corresponding to a substantially constant peak negative pressure across the valve.

[0039] At point C, the pressure across the valve is at its peak negative pressure, and immediately thereafter, the pressure across the valve becomes less negative (increases). In this embodiment, the stored potential energy 420 begins to unload from the support structure 102 in the form of kinetic energy 440. Thus, immediately after point C, or just as the pressure across the valve decreases from the peak negative pressure, there is a sharp increase 448 in the kinetic energy 440. The kinetic energy 440 reaches the transition energy 450, where the kinetic energy initially reaches a steady state and then, as the potential energy 420 continues to decrease through region 408, the kinetic energy gradually increases. In this embodiment, the kinetic energy 440 can be described as behaving substantially like a step function at both point B and point C.

[0040] The increase 448 in the kinetic energy 440 corresponds to a pre - movement of the support structure back towards the open position (more details of this movement are described later). At point C, the leaflets 110 are still fully engaged. As the pressure becomes less negative towards point D, the leaflets 110 disengage from the fully - engaged state. In some embodiments, at point D, the valve 100 can open up to 20% or more (i.e., the valve 100 allows 20% or more of its fluid flow in the normal open state), in other embodiments, the valve 100 can fully open at point D or before reaching point D, and in still other embodiments, the valve 100 fully opens just as the peak positive pressure of the subsequent cycle is reached. This increase 448 in kinetic energy is driven by the unloading of the potential energy 420 stored in the form of elastic deformation of the support structure 102. Thus, the support structure 102 has the advantage of pre - transitioning (e.g., springing back or rebounding) to its open position or pre - transitioning towards its open position before the leaflets 110 disengage from the fully - engaged state and before the blood begins to flow through the interior of the valve 100. The benefits of this pre - transition 448 can include a significantly reduced pressure gradient or resistance to opening, which in turn can result in a lower effective orifice area (EOA) and increased effective forward blood flow.

[0041] As mentioned above, in the actual operation of the valve 100, the pressure across the valve may not exhibit a constant peak negative pressure as shown in region 406. Instead, the pressure across the valve may exhibit a curved or parabolic behavior, with the peak negative pressure at the apex. In some embodiments, the peak negative pressure across the valve is approximately 120 mmHg. However, it is emphasized that this is only an example and other peak negative pressures may be exhibited. In the embodiment described with respect to Figure 4A the pre - transition 448 begins immediately after the peak negative pressure when the pressure across the valve becomes less negative. Figure 4B

[0042] However, in other embodiments, the support structure 102 can be configured such that this anticipatory transition begins at a later time. In some exemplary embodiments, the anticipatory transition can occur when the pressure across the valve is 90 - 99.9% of the peak pressure across the valve, when the pressure across the valve is 85 - 95% of the peak pressure across the valve, when the pressure across the valve is 75 - 90% of the peak pressure across the valve, when the pressure across the valve is 50 - 75% of the peak pressure across the valve, or when the pressure across the valve is 25 - 50% of the peak pressure across the valve.

[0043] Figure 5A is a partial side view depicting an exemplary embodiment of the support structure 102, where the vectors simulate the relative velocity across the surface of the elastic support structure 102 as the structure 102 transitions from a closed position to an open position. In this example, the velocity vectors are at the time when the anticipatory transition begins (e.g., immediately Figure 4B after point C in). Here, only the front half of the support structure 102 is shown, and for ease of illustration, the leaflets 110 (but their presence) have been omitted. The position where the upstream end 112 - 1 of the leaflet 110 - 1 will be placed is indicated by an arrow.

[0044] The support structure 102 has a plurality of first sites 501 and second sites 502 that are aligned with the downstream end 107 of the protrusion 106 and the upstream end 112 of the leaflet 110. In Figure 5A the positions of the first sites 501 - 1 and 501 - 3 respectively indicate directly upstream of the downstream ends 107 - 1 and 107 - 3. The position of the second site 502 - 1 indicates directly upstream of the upstream leaflet end 112 - 1. When the first site 501 - 1 is aligned with the end 107 - 1 and extends radially outward, the first site 501 - 1 is below the sidewall of the protrusion 106 - 1 and along the flange 121 and directly upstream of the downstream end 107 - 1. Although in various embodiments there may be a degree of asymmetry, in normal operation, embodiments of the valve 100 operate in a symmetric manner, where each leaflet 110 and protrusion 106 generally move in the same manner back and forth between the open position and the closed position.

[0045] The longer the velocity vector, the greater the magnitude of the instantaneous velocity. As can be seen here, the relatively highest instantaneous velocity occurs along the protrusion 106, specifically at and near the downstream end 107, because these sites are regions with the highest amount of elastic deformation at the closed position.

[0046] In many embodiments, when the support structure 102 begins to anticipatorily transition from the closed position to the open position, the elastic upstream edge 120 also exhibits movement. In Figure 5AIn the embodiment, the upstream edge 120 moves in the upstream direction at each first portion 501, and simultaneously, the upstream edge 120 moves in the downstream direction at each second portion 502.

[0047] This characteristic is shown in Figure 5B wherein the flange 121 is shown with corresponding velocity vectors, and for the sake of illustration, the magnitudes of these velocity vectors have been increased compared to Figure 5A . The remainder of the support structure 102 is shown schematically, and for clarity, the remaining velocity vectors (see Figure 5A ) and the leaflets 110 are no longer shown.

[0048] In Figure 5B , the velocity vectors have a generally sinusoidal distribution along the upstream edge 120 around the entire periphery of the valve 100 translated into a sinusoidal displacement. For example, the region surrounding each first portion 501 has velocity vectors in the downstream direction, where the maximum magnitude exists at or near the first portion 501 itself, and these velocity vectors generally decrease or taper as the distance from the first portion 501 increases on both sides. Conversely, the region surrounding each second portion 502 has velocity vectors in the upstream direction, where the maximum magnitude exists at or near the second portion 502 itself, and these velocity vectors generally decrease or taper as the distance from the second portion 502 increases on both sides. The third portion 503 is located approximately in the middle between each first portion 501 and the immediately adjacent second portion 502, and the third portion 503 is the position where the velocity vector reaches zero, and the velocity vector reaching zero indicates no movement at that portion and at that time point. The portion 503 is a pivot point between the oscillating segments. For each portion around the periphery of the upstream edge 120, as traveling radially outward from the inner edge of the flange 121 to the outer edge of the flange 121, the velocity vectors become relatively larger (indicated by the concentric three rows of vectors in Figure 5B ).

[0049] Thus, in many embodiments, when considering the edge 120 as a whole, the velocity and motion profile are generally sinusoidal, where the specific points along the upstream edge 120 can alternate from full upstream displacement to neutral displacement, full downstream displacement, back to neutral displacement, etc., depending on the location along the upstream edge 120 being examined. In the closed position, the upstream edge 120 has a sinusoidal-shaped surface, where portion 501 is displaced relatively downstream and portion 502 is displaced relatively upstream. In the open position, the upstream edge 120 also has a sinusoidal-shaped surface but with a complementary or opposite profile, where portion 501 is displaced relatively upstream and portion 502 is displaced relatively downstream. In the embodiment shown herein, when the valve 100 transitions between the open and closed positions, the pivot point portion 503 does not cause relative displacement.

[0050] Similarly, in this embodiment, the base edge 120 does not have a sinusoidal shape at the neutral position but is planar or flat. In alternative embodiments where the base edge 120 is not planar at the neutral position, such as in a scalloped aortic configuration where the base edge 120 is scalloped, the sinusoidal displacement starts from the scalloped neutral position as opposed to a planar neutral position. Although the velocities and displacements are described as being sinusoidal, these velocities and displacements can also be substantially sinusoidal, and after reading this description, one of ordinary skill in the art will readily recognize that those shapes are substantially sinusoidal. In any event, those skilled in the art understand that the sine function can vary in amplitude and frequency. They also understand that the manufacture and use of the prosthetic valve can result in deviations due to manufacturing differences, differences caused by implantation, the duration of valve implantation (e.g., material accumulation such as calcification, etc.), and / or noise, and that the effects of these deviations on the sine function fall within the scope of the term sinusoidal as used herein.

[0051] Figure 5A-5B Depict the instantaneous velocity on the support structure 102 at the time when the previous transition starts (which can follow Figure 4B point C) or at other times indicated elsewhere in this document. Continue to move in these directions at the last decreasing velocity until the support structure 102 reaches its open position (see Figure 2A-2C ), which can occur any number of times. For example, if the support structure 102 reaches its open position when the pressure across the valve becomes positive, it can continue from the start of the previous transition (e.g., just Figure 4AAfter point C, when the pressure is 90 - 99.9% of the peak value, 85 - 95% of the peak value, 75 - 90% of the peak value, 50 - 75% of the peak value, or 25 - 50% of the peak value, etc., it moves in the direction indicated by these vectors until the time when the pressure across the valve becomes positive. Similarly, if when the maximum fluid flow occurs in the downstream direction (e.g., peak positive pressure), the support structure 102 reaches its fully open position, it can continue to move in the direction indicated by these vectors from the start of the leading transition until the time when the pressure across the valve becomes positive.

[0052] Figure 5A-5B Depicts the velocity when the support structure 102 moves from the closed position (see, for example Figure 3A -C) towards the open position (see, for example Figure 2A-2C ). In these embodiments, when the support structure 102 moves from the open position to the closed position, a similar but opposite movement (not shown) occurs. Thus, for example, Figure 5A the directions of the velocity vectors in can each be reversed to depict the direction of movement when the support structure 102 moves from the open position to the closed position (e.g., the protrusion 106 moves radially inward, the first portion 501 moves in the upstream direction, the second portion 502 moves in the downstream direction, etc.). The magnitude of the instantaneous velocity will be relatively less than those instantaneous velocities depicted in Figure 5A-5B because the peak positive pressure across the valve (e.g., approximately 20 mmHg) is generally significantly less than the peak negative pressure across the valve (e.g., approximately 120 mmHg).

[0053] In many embodiments, when the structure 102 transitions between the closed position and the open position, the downstream end 107 of the support structure 102 exhibits the maximum displacement. When the support structure 102 leaves the open position or the closed position, the downstream end 107 of the support structure also exhibits a relatively high instantaneous velocity.

[0054] Depending on the size of the valve, embodiments of the valve 100 can have different maximum displacements as measured from the neutral position of the valve (see, for example Figure 1A-1B ). The following paragraphs describe embodiments having various displacements and velocities obtained from exemplary mitral valve configurations and aortic valve configurations. The exemplary mitral valve configuration has a displacement from the base edge of the leaflet 112 (see Figure 5A) The diameter of 27 millimeters and the length of the protrusion 510 of 13.5 mm are measured along the central longitudinal axis of the protrusion in a straight line position. The exemplary aortic configuration has a diameter of 23 millimeters and a protrusion length 510 of 12.5 mm. The speeds and displacements described herein increase and decrease proportionally in a substantially linear manner between multiple sizes. Various sizes of the embodiments regarding the mitral valve and the aorta are described in more detail below.

[0055] For a mitral valve configuration transitioning from a neutral position to a closed position, in some embodiments, the maximum radially inward displacement (D MRI ) of the downstream end 107 is 0.45 millimeters (mm) or greater, in some embodiments, D MRI is 0.50 mm or greater, in some embodiments, D MRI is 0.55 mm or greater, in some embodiments, D MRI is 0.60 mm or greater, in some embodiments, D MRI is 0.65 mm or greater, and in some embodiments, D MRI is 0.70 mm or greater. However, depending on the actual implementation, in certain exemplary embodiments, D MRI does not exceed 1.50 mm, and in other embodiments, D MRI does not exceed 0.90 mm.

[0056] For a mitral valve configuration transitioning from a neutral position to an open position, in some embodiments, the maximum radially outward displacement (D MRO ) of the downstream end 107 is 0.020 mm or greater, in some embodiments, D MRO is 0.021 mm or greater, and in some embodiments, D MRO is 0.022 mm or greater. However, depending on the actual implementation, in certain exemplary embodiments, D MRO does not exceed 0.060 mm, and in other exemplary embodiments, D MRO does not exceed 0.030 mm.

[0057] For an aortic valve configuration transitioning from a neutral position to a closed position, in some embodiments, the maximum radially inward displacement (D MRI ) of the downstream end 107 is 0.31 millimeters (mm) or greater, in some embodiments, D MRI is 0.35 mm or greater, in some embodiments, D MRI is 0.38 mm or greater, in some embodiments, D MRI is 0.40 mm or greater, in some embodiments, D MRIis 0.45 mm or greater, and in some embodiments, D MRI is 0.50 mm or greater. However, depending on the actual implementation, in certain exemplary embodiments, D MRI does not exceed 1.20 mm, and in other exemplary embodiments, D MRI does not exceed 0.60 mm.

[0058] In many embodiments, when the structure 102 begins to transition from the closed position to the open position, the downstream end 107 of the support structure 102 also exhibits a specific instantaneous velocity. For a mitral valve configuration transitioning from the closed position to the open position, in some embodiments, at the start of the initial transition, the instantaneous velocity (V ICO ) of each downstream end 107 is 5.10 millimeters per second (mm / s) or greater, and in some embodiments, V ICO is 5.20 mm / s or greater, and in some embodiments, V ICO is 5.30 mm / s or greater, and in some embodiments, V ICO is 5.40 mm / s or greater, and in some embodiments, V ICO is 5.50 mm / s or greater, and in some embodiments, V ICO is 5.60 mm / s or greater, and in some embodiments, V ICO is 5.80 mm / s or greater, and in some embodiments, V ICO is 6.00 mm / s or greater, and in some embodiments, V ICO is 6.20 mm / s or greater, and in some embodiments, V ICO is 6.40 mm / s or greater, and in some embodiments, V ICO is 6.60 mm / s or greater, and in some embodiments, V ICO is 6.80 mm / s or greater, and in some embodiments, V ICO is 7.00 mm / s or greater, and in some embodiments, V ICO is 7.10 mm / s or greater. However, depending on the actual implementation, in certain exemplary embodiments, V ICO does not exceed 14.50 mm / s, and in other exemplary embodiments, V ICO does not exceed 7.8 mm / s.

[0059] For a mitral valve configuration transitioning from the open position to the closed position, in some embodiments, at the start of the initial transition, the instantaneous velocity (V IOC ) of each downstream end 107 is 4.10 mm / s or greater, and in some embodiments, VIOC is 4.20 mm / s or greater, and in some embodiments, V IOC is 4.30 mm / s or greater, and in some embodiments, V IOC is 4.40 mm / s or greater, and in some embodiments, V IOC is 4.50 mm / s or greater. However, depending on the actual implementation, in certain exemplary embodiments, V IOC does not exceed 10.00 mm / s, and in other exemplary embodiments, V IOC does not exceed 5.00 mm / s.

[0060] For an aortic valve configuration transitioning from a closed position to an open position, in some embodiments, V ICO is 14.60 millimeters per second (mm / s) or greater, and in some embodiments, V ICO is 14.75 mm / s or greater, and in some embodiments, V ICO is 15.00 mm / s or greater, and in some embodiments, V ICO is 16.00 mm / s or greater, and in some embodiments, V ICO is 17.00 mm / s or greater, and in some embodiments, V ICO is 18.00 mm / s or greater, and in some embodiments, V ICO is 18.50 mm / s or greater. However, depending on the actual implementation, in certain exemplary embodiments, V ICO does not exceed 40.00 mm / s, and in other exemplary embodiments, V ICO does not exceed 21.00 mm / s.

[0061] For an aortic valve configuration transitioning from an open position to a closed position, in some embodiments, in some embodiments, V IOC is 6.10 mm / s or greater, and in some embodiments, V IOC is 6.20 mm / s or greater, and in some embodiments, V IOC is 6.50 mm / s or greater, and in some embodiments, V IOC is 7.00 mm / s or greater, and in some embodiments, V IOC is 7.50 mm / s or greater. However, depending on the actual implementation, in certain exemplary embodiments, V IOC does not exceed 15.00 mm / s, and in other exemplary embodiments, V IOC does not exceed 8.5 mm / s.

[0062] By means of a balanced use of materials, cross-section, stiffness, and elasticity for both the leaflets 110 and the support structure 102, the characteristics of the previously mentioned embodiments are achieved. For example, if the support structure is made of a plastically deformable material, the support structure will not respond in such a way. Instead, the support structure will assume a deformed shape defined by the load unloaded by the leaflets, but the support structure material will gradually relax and lose its elasticity to return to the nominal geometry.

[0063] Conversely, if the leaflets are less structurally compliant, each leaflet will deform significantly, and the amount of load unloaded onto the support structure will be significantly reduced, and thus the potential energy stored in the support structure for the leading transition will be significantly reduced. This is typically the case for tissue-based prosthetic heart valves, where the leaflets are mainly made of bovine or porcine pericardial tissue, which can be deformed completely even with a very low elastic modulus. These tissue-based valves have a support structure typically made of a relatively rigid substrate, such as elgiloy wire or a thick curved section of polyoxymethylene or acetal polymer that has a large stiffness due to the moment of inertia of the cross-section.

[0064] The amount of stretch in the leaflets also affects the mechanism. If the support structure experiences very little fully closed load, there will be no stored potential energy to drive the leading transition mechanism, and thus as the minimum pressure becomes less negative, the leaflets will elastically recover, but the leaflets do not open the valve before the pressure becomes positive because the support structure has not yet recovered.

[0065] In the embodiments described herein, when the leaflets 110 engage, the leaflets 110 unload the load onto the support structure 102, and the support structure 102 in turn deforms. The magnitude of the deformation ensures that there is no additional in-plane stretch of the leaflets 110 and allows the leading transition mechanism to occur. Moreover, in many embodiments, the base 105 (and the upstream base edge 120) is flexible and allows for significant movement. If the base is rigidly constrained or prevented from deforming freely, as can be the case for a substantially rigid double-flange configuration, the resulting strain energy in the system to promote the leading transition will be reduced, and the maximum stress level will be significantly increased.

[0066] The support structure 102 can be prepared from one or more materials (e.g., a core structure of one material with a coating of the same or another material). The material is preferably a polymeric material (such as polyetheretherketone (PEEK), polyurethane, polyetherimide (PEI) (such as ULTEM)), any of the materials used to form the leaflets 110, and other materials. The leaflets 110 are also preferably prepared from polymeric materials including any biostable polyurethanes and polyurethane compositions known in the art (e.g., polyurethanes containing polysiloxanes, etc.). Examples of polyurethane-containing leaflets are described in U.S. Patent No. 6,984,700, U.S. Patent No. 7,262,260, U.S. Patent No. 7,365,134, and "Silicone-containing Copolymers: Synthesis, Properties, and Applications" by Yilgor et al. published in Prog. Polym. Sci. (2013), all of which are incorporated herein by reference in their entirety for all purposes. Materials with near-ideal isotropic non-creep properties are particularly suitable for use in many embodiments.

[0067] While many materials can be used, it may be preferred that the selected material has an appropriate elastic modulus to allow for the load relief and elastic deformation characteristics described herein. In many exemplary embodiments, the elastic modulus of the leaflets 110 is in the range of 10 - 45 megapascals (MPa). In certain exemplary embodiments, the elastic modulus of the leaflets 110 is in the range of 20 - 35 MPa, and in certain other exemplary embodiments, the elastic modulus of the leaflets 110 is in the range of 23 - 32 MPa, and in still other exemplary embodiments, the elastic modulus of the leaflets 110 is in the range of 25 - 30 MPa. In many exemplary embodiments, the elastic modulus of the support structure 102 is in the range of 3000 - 5000 MPa. In certain exemplary embodiments, the elastic modulus of the support structure 102 is in the range of 3300 - 3500 MPa.

[0068] Embodiments of the support structure 102 are relatively less rigid compared to prior art "rigid" valves. In many embodiments, the support structure 102 has a stiffness per unit force (R UF )(square millimeters) of 600 to 1500. In other embodiments, the support structure 102 has an R UF of 900 - 1400, and in still other embodiments, the support structure 102 has an R UF of 1100 - 1300. The protrusions 106 can be modeled as elastic beams, and R UF can be calculated according to (1):

[0069]

[0070] Wherein, E is Young's modulus, I is the moment of inertia of the cross-section, P is the force at the downstream end 107, L is the length 510 of the protrusion 106, and δ is the displacement at the downstream end 107.

[0071] In some embodiments, the support structure 102 may include a core frame. The leaflets 110 may be formed seamlessly on the core frame, such as by a casting process (e.g., dip casting), a molding process, or other processes. An exemplary dip casting process suitable for forming the leaflets is described herein. The core frame may be prepared from a suitable material (such as those described herein). This may be done by machining or injection molding. The core frame may then be placed on a dip mandrel having the shape of the inner surface of the support structure and the leaflets. The mandrel may be inserted into the polymer solution using forming equipment that encapsulates the core frame and casts the leaflets in the desired form.

[0072] The core frame and the mandrel may be dipped into the polymer solution not only at high temperatures but also under high humidity conditions and then withdrawn. However, the methods disclosed herein are not limited thereto. In some exemplary embodiments, the relative humidity (RH) may be in the range of 20 - 80%, and the temperature may be in the range of 20 - 50 °C. This step may result in the support structure 102 and the leaflets 110 being presented together in an integrally formed but unpolished state.

[0073] The dipping step may be performed only once to achieve a fully formed (but unpolished) valve, or it may be performed multiple times (e.g., two, three, or as many times as desired). In one embodiment, the core frame is prepared from a first material (e.g., PEEK) different from the polymer material used to prepare the leaflets. In this case, it may be desirable to form the leaflets onto the core frame only after the core frame has been pre-coated with the leaflet polymer to provide greater cohesion. The core frame may be pre-coated by first dipping it into the leaflet polymer having a first viscosity. This may be done with or without a mandrel. If done with a mandrel, the resulting leaflets may be removed. The pre-coated core frame may then be placed on the mandrel and dipped again, this time into the leaflet polymer having the same or a relatively higher viscosity. This second dipping may result in the formation of the body of the fully formed leaflets integrally formed with the support structure. Using a low viscosity followed by a higher viscosity regime may allow for the formation of a thin pre-coat that does not significantly distort the shape of the underlying core frame, followed by the formation of leaflets having the desired thickness.

[0074] The support structure 102 and the leaflets 110 can then be trimmed and otherwise polished to achieve accurate and precise edges and surface flatness. This can occur, for example, by laser cutting, ultrasonic trimming, water jet, mechanical clamshell cutters, and the like. The suture cuff can be coupled to the support structure 102 (using any flanges 121, if present), and the final device can be encapsulated in a desired sterile container.

[0075] One of ordinary skill in the art will readily recognize that, given this description, many variations of suitable dip casting procedures, pressures, and temperatures not set forth herein are also suitable for preparing the prosthetic heart valves described herein. Similarly, given this description, one of ordinary skill in the art will also recognize alternative dip casting options that can be used to prepare the prosthetic heart valves described herein.

[0076] The embodiments of the valve 100 described herein are suitable for implantation into the body of a subject (human or animal). This can be done using any number of medical procedures. Preferably, these embodiments of the valve 100 are used to be directly implanted, for example, into the mitral annulus or aortic annulus using a cardiac incision procedure.

[0077] In one such exemplary cardiac incision implantation procedure, an appropriately sized replacement valve can be determined and then the cardiac incision access procedure can be performed by a surgeon to gain access to the malfunctioning valve in the heart to be replaced. The surgeon can then position the selected prosthetic heart valve 100 at the appropriate location on the malfunctioning valve and attach the valve 100 to the surrounding tissue. The attachment can be performed, for example, by securing the suture cuff to the tissue using one or more sutures. Before attachment, if the surgeon determines that the selected valve size is not optimal, a different valve of a different size can be selected and placed at the appropriate location within the heart. In some other embodiments, the malfunctioning valve can be removed before positioning the valve 100 at the intended site. Once the valve 100 is attached, the incised heart chamber is sutured and the procedure is complete.

[0078] The embodiments of the valve 100 for cardiac incision procedures do not radially contract to insert into an intravascular delivery device (e.g., a catheter), nor are they transapical delivery devices. However, in other embodiments, the valve 100 can be configured with a support structure that can radially contract, which allows the transverse dimension of the valve 100 to be reduced to an extent sufficient to permit insertion into a suitably sized blood vessel or a transapical delivery device.

[0079] For most aortic valve replacement configurations, valve 100 can be implemented to mate with aortic tissue annuli in the following sizes: 17 mm, 19 mm, 21 mm, 23 mm, 25 mm, and 27 mm. Other sizes can be implemented, including: 18 mm, 20 mm, 22 mm, 24 mm, 26 mm, 28 mm, and 29 mm, as well as non-integer sizes between those listed (where there are many). This dimension is generally also referred to as the inner diameter or "ID" of the valve and refers to the lateral dimension of the valve at a location commensurate with leaflets 110. The valve can have an even larger diameter elsewhere (such as at the location of flange 121). For most mitral valve replacement configurations, valve 100 can be implemented in any of the following IDs: 23 mm, 25 mm, 27 mm, 29 mm, and 31 mm. Other sizes can be implemented, including: 22 mm, 24 mm, 26 mm, 28 mm, 30 mm, 32 mm, as well as non-integer sizes between those listed (where there are many).

[0080] Although support structure 102 can be in various non-cylindrical shapes, in all embodiments described herein, support structure 102 can be substantially cylindrical or cylindrical. As understood by those of ordinary skill in the art, being "cylindrical" does not require support structure 102 to be in the form of a perfect geometric cylinder (e.g., vertical walls oriented at right angles with respect to a circular cross-section), rather, it requires support structure 102 to be placed along a portion of a hypothetical geometric cylinder (with only minor deviations). For example, the entire inner lumen surface of support structure 102 (the surface adjacent to the blood flow) can be cylindrical as the term is used herein. Similarly, those of ordinary skill in the art understand that a "substantially cylindrical" support structure 102 is allowed to deviate more from a mathematical cylinder than a mere "cylindrical support structure" and will readily recognize those support structures that are considered substantially cylindrical.

[0081] Although the overall support structure 102 can be cylindrical or substantially cylindrical, it is also applicable that only a portion of support structure 102 can be cylindrical or substantially cylindrical and the remainder of support structure 102 is non-cylindrical. For example, in some embodiments, only the portion of support structure 102 along curved interface 107 can be cylindrical or substantially cylindrical.

[0082] When the support structure 102 is formed from a core frame coated with a polymer, then in some embodiments, only the core frame (in whole or in part) may be cylindrical or substantially cylindrical, while the outer surface of the polymer coating is not cylindrical or not substantially cylindrical. For example, in some embodiments, the inner lumen surface of the core frame is cylindrical, and the outer surface of the polymer coating (along the inner lumen of the core frame) is substantially cylindrical (or even non-cylindrical) due to variations in the coating thickness.

[0083] All embodiments of the valve 100 described herein may also be provided to (or retained by) medical professionals as part of a set (or group) of prosthetic valves sized for various tissue annulus dimensions. The sizes may include any combination of two or more of the following sizes: 17mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, and 31mm.

[0084] Although the embodiments described herein may exhibit active assistance in valve opening and closing by storing and releasing energy in response to pressure differences in the blood flow, these valve embodiments, when considered as a whole, may be characterized as "passive" devices that are not actively powered by an artificial power source. Some examples of actively powered devices include machines for cardiopulmonary bypass (e.g., heart-lung machines) and implantable artificial hearts.

[0085] The behavior of the valve 100 can be evaluated in various ways. For example, the behavior of the valve 100 can be observed after implanting the valve 100 in a subject. The pressure across the valve can be measured directly in the subject, for example, by placing catheter-based pressure sensors on opposite sides of the valve. Alternatively, the behavior of the valve 100 can be evaluated by testing the valve 100 in a test device that applies fluid pressure in a manner that simulates the pressure across the valve in the subject. Further, the behavior of the valve 100 can be evaluated by applying computer simulations such as an idealized model of the pressure across the valve in the subject as described with respect to Figure 4A -B.

[0086] Reviewing and / or supplementing the embodiments described thus far, various aspects of the subject matter are set forth below, with an emphasis herein on the relevance and interchangeability of the following embodiments. In other words, an emphasis is placed on the fact that, unless otherwise explicitly stated or logically inconsistent, each feature of an embodiment can be combined with each feature and every other feature.

[0087] In many embodiments, a prosthetic heart valve is provided that includes a plurality of synthetic leaflets and a support structure that includes a plurality of projections coupled to the plurality of leaflets and a base upstream of the plurality of projections, wherein the plurality of projections and the base are elastic. The prosthetic heart valve can have a closed position and an open position, and the plurality of leaflets and the support structure move between the closed position and the open position.

[0088] In certain embodiments, the prosthetic heart valve can be configured to permit fluid to flow in the correct upstream-to-downstream direction when the fluid pressure across the valve is positive, and configured such that when the fluid pressure across the valve is a peak negative pressure, the plurality of leaflets are in a engaged state. The prosthetic heart valve can be configured such that when the fluid pressure across the valve is a negative value less than the peak negative pressure, the plurality of projections automatically begin to move from the closed position to the open position.

[0089] In certain embodiments, the support structure has a perimeter, and the base includes an edge that extends around the perimeter of the support structure. Each of the plurality of leaflets can have an upstream end, and each of the plurality of projections can have a downstream end. In certain embodiments, the edge can include: a first portion that is located immediately upstream of each downstream end of the plurality of projections such that a plurality of first portions are present on the edge; and a second portion that is located immediately upstream of each upstream end of the plurality of leaflets such that a plurality of second portions are present on the edge, wherein at a first time during movement of the support structure from the closed position to the open position, each first portion moves in an upstream direction and each second portion moves in a downstream direction.

[0090] In certain embodiments, the first time is when the fluid pressure across the valve is 90 - 99.9% of the peak negative pressure, 85 - 95% of the peak negative pressure, or 25 - 75% of the peak negative pressure. The first time can be when the fluid pressure across the valve is a negative value. In certain embodiments, as the fluid pressure across the valve transitions from 75% of the peak negative pressure to zero, each first portion of the edge continuously moves in a downstream direction and each second portion of the edge continuously moves in an upstream direction. In certain embodiments, in response to the fluid pressure across the valve transitioning from the peak negative pressure to a smaller negative pressure, each first portion of the edge moves in a downstream direction and each second portion of the edge moves in an upstream direction. The plurality of leaflets can begin to disengage at the first time. Moreover, at the first time, each downstream end of the plurality of projections can move in a radially outward direction.

[0091] In certain embodiments, the support structure includes a suture cuff and no more than one suture cuff flange.

[0092] In some embodiments, the heart valve is an aortic replacement valve or a mitral replacement valve, and the heart valve includes exactly three synthetic leaflets. In some embodiments, the heart valve is a mitral replacement valve that includes exactly two synthetic leaflets.

[0093] In some embodiments, the support structure cannot be radially contracted for placement within an intravascular delivery device. In some embodiments, the support structure cannot be radially contracted for placement within a transapical delivery device.

[0094] In some embodiments, the support structure and the plurality of leaflets are formed from the same material. In some embodiments, the support structure includes a coating, and the plurality of leaflets is a continuation of the coating. The plurality of leaflets can be a polymer.

[0095] In some embodiments, the plurality of leaflets are not sutured to the support structure. The plurality of leaflets can be seamlessly coupled to the support structure. The plurality of leaflets and the support structure can be an integral body.

[0096] In many embodiments, the prosthetic heart valve is neither part of a cardiopulmonary bypass machine or an implantable artificial heart, nor a prosthetic heart valve powered by an artificial power source.

[0097] In some embodiments, the support structure has an inner diameter selected from: 17 millimeters (mm), 19 mm, 21 mm, 23 mm, 25 mm, 27 mm, 29 mm, and 31 mm.

[0098] In some embodiments, the plurality of leaflets have a first elastic force, and the support structure has a second elastic force, and the first elastic force can be in the range of 10 - 45 megapascals (MPa). In some embodiments, the first elastic force can be in the range of 20 - 35 MPa. In some embodiments, the first elastic force can be in the range of 25 - 30 MPa. In some embodiments, the second elastic force can be in the range of 3000 - 5000 MPa. In some embodiments, the second elastic force can be in the range of 3300 - 3500 MPa.

[0099] In some embodiments, the support structure can have a stiffness per unit force between 600 and 1500 square millimeters. In some embodiments, the support structure can have a stiffness per unit force between 900 and 1400 square millimeters. In some embodiments, the support structure can have a stiffness per unit force between 1100 and 1300 square millimeters.

[0100] The plurality of protrusions can each have a downstream end. In some mitral valve embodiments, wherein, just when transitioning from the closed position to the open position, the downstream ends can each exhibit an instantaneous velocity (V) of 5.10 millimeters per second (mm / s) or greater ICO)。In various embodiments, V ICO can be any of a plurality of values and ranges between 5.10 mm / s and 14.50 mm / s. In certain embodiments, just as the transition is made from the open position to the closed position, the downstream ends can each exhibit an instantaneous velocity (V IOC ) of 4.10 millimeters per second (mm / s) or greater. In various embodiments, V IOC can be any of a plurality of values and ranges between 4.10 mm / s and 10.00 mm / s.

[0101] In certain aortic embodiments, where, just as the transition is made from the closed position to the open position, the downstream ends can each exhibit an instantaneous velocity (V ICO ) of 14.60 millimeters per second (mm / s) or greater. In various embodiments, V ICO can be any of a plurality of values and ranges between 14.60 mm / s and 40.00 mm / s. In certain embodiments, where, just as the transition is made from the open position to the closed position, the downstream ends can each exhibit an instantaneous velocity (V IOC ) of 6.10 millimeters per second (mm / s) or greater. In various embodiments, V IOC can be any of a plurality of values and ranges between 6.10 mm / s and 15.00 mm / s.

[0102] The prosthetic heart valve can have a closed position, a neutral position, and an open position, and, during valve operation, the plurality of leaflets and support structures transition between the closed position, the neutral position, and the open position. In certain mitral valve embodiments, during the transition from the neutral position to the closed position, the downstream ends can each move inwardly 0.45 millimeters (mm) or more. In various embodiments, the downstream ends can each move inwardly a distance between 0.45 mm and 1.50 mm. In certain aortic embodiments, during the transition from the neutral position to the closed position, the downstream ends can each move inwardly 0.31 millimeters (mm) or more. In various embodiments, the downstream ends can each move inwardly a distance between 0.31 mm and 1.20 mm.

[0103] Where a range of values is provided, each intermediate value between the upper and lower limits of the range (to the extent of one-tenth of the unit of the lower limit, unless the context clearly dictates otherwise) and any other stated value or intermediate value within the stated range is included within the present disclosure and can be claimed as a unique value or a smaller range. Where the stated range includes one or both of these limits, ranges excluding any one or both of those included limits are also included within the present disclosure.

[0104] Where discrete values or ranges of values are provided, unless otherwise indicated, the value or range of values may be claimed more broadly than as a discrete numerical value or range of numerical values. For example, each value or range of values provided herein may be claimed as an approximation, and at all times, this paragraph serves as a premise basis and written support for introducing claims that recite each such value or range of values as "about" the value, "about" the range of values, "approximately" the value, and / or "approximately" the range of values. Conversely, if a value or range of values is set forth as approximate or approximate (e.g., about X or approximately X), the value or range of values may be claimed discretely without using such terms of broadened meaning.

[0105] However, in the absence of an express recitation of the value or range of values in the claims, the specification should in no way be construed as meaning that the subject matter disclosed herein is limited to a particular value or range of values. Values and ranges of values are provided herein merely as examples.

[0106] All features, elements, components, functions, and steps described with respect to any embodiment provided herein are intended to be freely combinable with and replaceable by those from any other embodiment. If a particular feature, element, component, function, or step is described only with respect to one embodiment, it should be understood that the feature, element, component, function, or step may be used with every other embodiment described herein, unless otherwise clearly stated. Accordingly, at all times, this paragraph serves as a premise basis and written support for introducing claims that combine features, elements, components, functions, and steps from different embodiments, or replace features, elements, components, functions, and steps from one embodiment with those from another embodiment, even where the following description does not clearly state that such combination or replacement is feasible in a particular instance. It is clearly recognized that an express recitation of each feasible combination and replacement would be overly burdensome. In particular, it is considered that those of ordinary skill in the art will readily recognize the permissibility of each such combination and replacement.

[0107] As used herein, and in the appended claims, unless the context clearly dictates otherwise, the singular forms "a", "an", and "the" include plural referents.

[0108] While embodiments are susceptible to various modifications and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the embodiments are not limited to the particular forms disclosed, but on the contrary, these embodiments will cover all modifications, equivalents, and alternatives falling within the spirit of the present disclosure. In addition, any feature, function, step, or element of an embodiment may be recited or added to the claims and the negative limitations that define the scope of the invention of the claims by features, functions, steps, or elements that do not fall within that scope.

Claims

1. A prosthetic heart valve, comprising: a plurality of leaflets, wherein each leaflet is synthetic; and a support structure, comprising: a plurality of protrusions coupled to the plurality of leaflets; and a base upstream of the plurality of protrusions, wherein the plurality of protrusions and the base are elastic, and the elastic modulus of the support structure is between 3000 and 5000 MPa, and wherein the elastic modulus of the plurality of leaflets is in the range of 10 - 45 MPa, wherein the prosthetic heart valve has a closed position and an open position, and the plurality of leaflets and the support structure move between the closed position and the open position, wherein the prosthetic heart valve is configured to permit fluid to flow in the correct upstream - to - downstream direction when the fluid pressure across the valve is positive, and is configured such that when the fluid pressure across the valve is a peak negative pressure, the plurality of leaflets are in a engaged state, and wherein the prosthetic heart valve is configured such that when the fluid pressure across the valve is a negative value less than the peak negative pressure, the plurality of protrusions automatically begin to move from the closed position to the open position; wherein the base has an upstream edge that is sinusoidal in the closed position and a reverse profile that is sinusoidal in the open position.

2. The prosthetic heart valve according to claim 1, characterized in that, The support structure has a periphery, and the upstream edge extends around the periphery of the support structure.

3. The prosthetic heart valve according to claim 2, characterized in that, Each of the plurality of leaflets has an upstream end, and each of the plurality of protrusions has a downstream end, and the upstream edge comprises: a first portion that is upstream of each downstream end of the plurality of protrusions, such that a plurality of first portions are present on the edge; and a second portion that is upstream of each upstream end of the plurality of leaflets, such that a plurality of second portions are present on the upstream edge, wherein, at a first time during the movement of the support structure from the closed position to the open position, each first portion moves in an upstream direction, and each second portion moves in a downstream direction.

4. The prosthetic heart valve according to claim 3, characterized in that, The first time is when the fluid pressure across the valve is 90 - 99.9% of the peak negative pressure.

5. The prosthetic heart valve according to claim 3, characterized in that, The first time is when the fluid pressure across the valve is 85 - 95% of the peak negative pressure.

6. The prosthetic heart valve according to claim 3, characterized in that, The first time is when the fluid pressure across the valve is 25 - 75% of the peak negative pressure.

7. The prosthetic heart valve according to claim 3, characterized in that, The first time is when the fluid pressure across the valve is negative.

8. The prosthetic heart valve according to claim 3, characterized in that, As the fluid pressure across the valve transitions from 75% of the peak negative pressure to zero, each first portion of the upstream edge continuously moves in a downstream direction, and each second portion of the upstream edge continuously moves in an upstream direction.

9. The prosthetic heart valve according to claim 3, characterized in that, In response to the fluid pressure across the valve transitioning from the peak negative pressure to a smaller negative pressure, each first portion of the upstream edge moves in a downstream direction, and each second portion of the upstream edge moves in an upstream direction.

10. The prosthetic heart valve according to claim 3, characterized in that, At the first time, the plurality of leaflets begin to disengage from the engaged state.

11. The prosthetic heart valve according to claim 3, characterized in that, At the first time, each downstream end of the plurality of protrusions moves in a radially outward direction.

12. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The support structure includes a suture cuff and no more than one suture cuff flange.

13. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The prosthetic heart valve is an aortic replacement valve or a mitral replacement valve, and the prosthetic heart valve includes three synthetic leaflets.

14. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The prosthetic heart valve is a mitral replacement valve including two synthetic leaflets.

15. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The support structure is not radially contractible for placement in an intravascular delivery device.

16. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The support structure is not radially contractible for placement in a transapical delivery device.

17. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The support structure and the plurality of leaflets are formed of the same material.

18. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The support structure includes a coating, and wherein the plurality of leaflets is a continuation of the coating.

19. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The plurality of leaflets is not sutured to the support structure.

20. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The plurality of leaflets is seamlessly coupled to the support structure.

21. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The plurality of leaflets and the support structure are an integral body.

22. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The prosthetic heart valve is neither part of a cardiopulmonary bypass machine nor an implantable artificial heart.

23. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The prosthetic heart valve is not powered by an artificial power source.

24. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The support structure has an inner diameter selected from: 17 mm, 19 mm, 21 mm, 23 mm, 25 mm, 27 mm, 29 mm, and 31 mm.

25. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The plurality of leaflets is a polymer.

26. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The elastic modulus of the plurality of leaflets is in the range of 20 - 35 MPa, and the elastic modulus of the support structure is between 3300 - 3500 Mpa.

27. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The elastic modulus of the plurality of leaflets is in the range of 25 - 30 MPa, and the elastic modulus of the support structure is between 3300 - 3500 MPa.

28. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The support structure has a stiffness per unit force between 600 and 1500 square millimeters.

29. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The support structure has a stiffness per unit force between 900 and 1400 square millimeters.

30. The prosthetic heart valve according to any one of claims 1-11, characterized in that, The support structure has a stiffness per unit force between 1100 and 1300 square millimeters.

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