Transcatheter artificial valve (THV) system

Abstract

To enable an accurate implant of an artificial valve and a precise development thereof in an aortic valve replacement surgery.SOLUTION: Disclosed is an artificial aortic valve which can expand and shrink in a radial direction and suitable for an implant of a balloon of a delivery catheter in a radially-shrunk state. The artificial aortic valve includes a support frame having three rows extending in a circumferential direction of an angled strut. One row of optional two continuous angles struts of the angles strut extending in the circumferential direction forms a peak and recess. A row of adjacent angled strut is mutually connected via a link (a diamond-shaped cell or a rhombohedral) and forms two rows of cell. The artificial aortic valve includes three valve projections, an inner skirt, and an outer skirt. The support frame and the delivery catheter provides a method for easily and accurately developing the artificial aortic valve at a target part.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to prosthetic systems, and more particularly to prosthetic transcatheter heart valve systems. [Background technology]

[0002] The function of a prosthetic heart valve is to replace a diseased natural heart valve. Replacement surgery can be performed surgically (using open-heart surgery) or percutaneously.

[0003] The design of the support frame plays a critical role in the performance of the prosthetic valve. For many years, the definitive treatment for this condition has been surgical repair or replacement of the heart valve through open-heart surgery, but such procedures are prone to numerous complications. Some patients cannot tolerate surgery due to the trauma associated with the procedure and the duration of extracorporeal blood circulation. As a result, many patients are deemed inoperable and remain untreated.

[0004] Instead of surgical procedures, percutaneous catheterization has been developed, which is much less invasive than open-heart surgery. In this procedure, the prosthetic valve is crimped onto a balloon at the tip of a flexible catheter, known as a transcatheter heart valve system (THV). The catheter is most commonly introduced into the blood vessels, usually via a peripheral artery (rarely via a vein). This may be the patient's common femoral artery, possibly the axillary or carotid artery, or most likely, a transapical route (through the cardiac peak). The catheter with the prosthetic valve crimped onto the balloon is advanced through the blood vessel until the crimped prosthetic valve reaches the implantation site. The valve can be expanded to a functional size in the place of the defective native valve by inflating the balloon to which the valve is attached. Alternatively, the prosthetic aortic valve may have a self-expanding stent or support frame that expands the valve to a functional size by withdrawing a retaining sheath. The artificial valve mentioned above is called a "balloon-expandable" valve, while the artificial valve described below is called a "self-expandable" valve.

[0005] Both balloon-expandable and self-expanding valves incorporate a support frame or stent, usually a tubular scaffold structure, and multiple leaflets, usually three.

[0006] The performance of a prosthetic valve is largely determined by the design of its support frame. To achieve long-term prosthetic valve performance, the support frame must have sufficient radial strength to withstand radially collapsing and compressive arterial forces. The support frame must also have sufficient fatigue resistance to withstand the arterial circulatory forces generated by the opening and closing of the prosthetic valve during systole and diastole. Considering these requirements, the design of a transcatheter prosthetic heart valve support frame should be based on structural robustness, sufficient radial strength or stiffness, and high fatigue strength. Furthermore, it is essential to optimize the size and / or axial length of the support frame to ensure a better interface with the native anatomy.

[0007] See patent documents relating to transcatheter aortic prosthetic heart valves (THVs) disclosed as U.S. Patent No. 5,627,992 and U.S. Patent No. 5,627,992. THVs manufactured using the configurations disclosed in the above patents have large size matrices, including conventional, medium, and oversized sizes, that are crimped directly onto the balloon of a delivery system.

[0008] The THV system disclosed in the above patent document addresses the following unmet clinical needs: It is to: 1. Severe aortic stenosis (moderate to high surgical risk, i.e., Society of Thoracic Surgeons (STS) risk level ≥ 4%). 2. Low-risk surgical population with STS risk level less than 4%. 3. Symptomatic moderate aortic stenosis. 4. Patients with low flow and low gradient. 5. Implants in young patients under 65 years of age. 6. Compatibility with bicuspid aortic valve anatomy. 7. Compatibility with highly calcified aortic root complex. 8. Compatibility with valve-in-valve interventions, i.e., SAVR-within-TAVR (a procedure in which a transcatheter aortic valve replacement (TAVR) is performed to treat aortic valve stenosis after SAVR) and TAVR-within-TAVR (a procedure in which a TAVR is performed to treat aortic valve stenosis after TAVR). 9. Compatibility with pulmonary valve replacement. 10. Treatment of aortic regurgitation (AR). 11. Treatment of asymptomatic severe aortic stenosis.

[0009] The frame of the preferred embodiment of the THV disclosed in the above invention has three rows of hexagonal cells.

[0010] Furthermore, in the case of balloon-expandable prosthetic heart valves, they are delivered to the implantation site by a balloon catheter. The delivery system, i.e., the balloon catheter, plays a very important role in expanding the balloon to accurately identify the deployment site where the prosthetic heart valve will be placed (implanted). There is a continuing need to optimally and accurately position the valve at the patient's desired implantation site and deploy it accurately.

[0011] In view of the above, therefore, a need has arisen for a stented transcatheter prosthetic heart valve system that overcomes the shortcomings of existing systems. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] International Publication No. 2018 / 109779 [Patent Document 2] US Patent Application Publication No. 2018 / 0289476 Summary of the Invention [Problem to be solved by the invention]

[0013] The present invention relates to a balloon-expandable prosthetic heart valve and delivery system comprising a balloon catheter. The invention described in the following description uniquely retains the core legacy technology of THVs disclosed in the aforementioned patent applications provided as background and incorporates several enhancements.

[0014] In aortic valve replacement, accurate placement and precise deployment of the prosthetic valve are crucial to achieving optimal performance. Optimal performance refers to reducing the transvalvular pressure difference (sustainable hemodynamics), preventing paravalvular regurgitation, and avoiding iatrogenic damage to the conduction system (which would require implantation of a new permanent pacemaker). In aortic valve replacement, the ideal implantation position for the prosthetic valve is, in principle, the midline position, attempting to align the prosthetic annulus (neoprosthetic annulus) with the native annulus. Implanting the prosthetic valve in this position has three important advantages:

[0015] The first advantage is improved anatomical placement of the prosthetic valve. The native annulus and its leaflets are It may be stenotic and calcified. In situ expansion of a prosthetic valve sized to the native annulus securely anchors the frame within the stenotic annulus with calcified leaflets, providing anatomic fixation that eliminates the risk of embolism due to prosthetic valve dislodgement.

[0016] The second advantage is minimal valve protrusion into the left ventricle. It is important to implant the prosthetic valve in the annular position and not deeply implant it on the ventricular side, i.e., in the subannular position, because of the presence of two critical anatomical regions below the aorta. The first region is the membranous septum between the atria and ventricles, which contains the dense cardiac conduction muscle (the atrioventricular node) that conducts electrical impulses to maintain a normal heartbeat. Ensuring that the prosthetic valve does not become lodged in the left ventricular outflow tract (LVOT) is important to reduce the risk of disrupting the cardiac conduction system. The second region is the aortic curtain and the position of the native mitral valve, which is located posterolateral to the aortic valve. An incorrectly positioned prosthetic valve may interfere with the normal function of the anterior mitral valve leaflet, thereby affecting mitral valve function. A prosthetic valve implanted using this recommended method minimizes the amount of prosthetic valve protrusion in the LVOT.

[0017] A third advantage is that it minimizes obstruction of the coronary artery ostia located along the coronary sinus of Valsalva or above the aortic root transition (aortic root transition). Ideally, the prosthetic valve does not obstruct blood flow to the coronary arteries by blocking or maintaining the ostia. By accurately implanting the prosthetic valve in a midline position, protrusion of the frame 101 into the left main artery can be minimized, preventing obstruction of blood flow to the coronary arteries. The prosthetic valve of the present invention avoids obstruction of the coronary artery ostia due to its large exposed outflow end, uncovered cells, and short frame height. [Means for solving the problem]

[0018] The present invention allows for accurate in-situ implantation and precise deployment of a prosthetic aortic valve. This is achieved through the design of the prosthetic aortic valve and delivery system of the present invention. The prosthetic aortic valve and its delivery system are described below.

[0019] The prosthetic aortic valve is radially expandable and is suitable for loading onto a balloon of a delivery catheter in a radially contracted state. The prosthetic valve includes a distal end, a proximal end, and a radially contractible and expandable support frame with three circumferentially extending angled strut rows: an upper row at the distal end, a lower row at the proximal end, and a middle row between them. The distal position refers to the position away from the surgeon. The lower row is toward the inflow end of the support frame. The angled strut rows have an undulating shape with peaks and valleys, with the peaks of the angled struts in the upper row facing the valleys of the angled struts in the middle row, and the peaks of the angled struts in the middle row facing the valleys of the angled struts in the lower row. The angled strut rows are connected to each other to form a support frame including two rows of cells adjacently arranged between the distal and proximal ends. The valleys of the top row of angled struts are connected to the corresponding peaks of the middle row of angled struts by links, which are rhomboid cells or rhomboid cells (with or without holes), thereby forming a top row of cells containing alternating octagonal cells with alternating rhomboid cells (with or without holes) at each commissure (junction). The rhomboid cells have an open structure, and the rhombohedrons have a solid structure. The valleys of the middle row of angled struts are connected to the corresponding peaks of the bottom row of angled struts by links, which are rhomboid cells (open structure) or rhombohedrons (solid structure), thereby forming a bottom row of cells containing alternating octagonal cells with alternating rhomboid cells at each commissure (junction).

[0020] The reduced number of rows and the special shape of the cells reduces shrinkage at the front of the frame during radial expansion, making it easier to accurately implant the prosthetic heart valve.

[0021] The two cell rows consist of an upper cell row located at the outflow end of the support frame and a lower cell row located at the inflow end of the support frame. The upper cell row contains three solid rhombohedrons with holes arranged at 120° angles to each other, forming three commissure attachment points to which the commissure attachment points or tabs of two adjacent valve leaflets attach.

[0022] In one embodiment, the prosthetic aortic valve includes three rows of circumferentially arranged angled struts forming two rows of cells, and a plurality of links, each link comprising either a diamond-shaped cell or a rhombohedron (with or without holes).

[0023] Two consecutive struts in the circumferentially arranged struts form a peak or a valley. The peaks of the struts in one row of the circumferentially arranged struts face the valleys of the struts in an adjacent row of the circumferentially arranged struts. The valleys of the struts in one row of the circumferentially arranged struts are connected to the corresponding peaks of the struts in the adjacent row of the circumferentially arranged struts via links. Thus, the peaks of one row of the circumferentially arranged struts face the corresponding valleys of the adjacent row of the circumferentially arranged struts. Similarly, the valleys of one row of the circumferentially arranged struts face the corresponding peaks of the adjacent row of the circumferentially arranged struts.

[0024] Connecting the angled struts of one row to the adjacent row with links creates a cellular structure with intersecting octagonal cells and rhomboidal cells or solid rhombohedrons. The three links of the upper cellular row are perforated rhombohedrons positioned at 120° angles to each other, forming three commissure (junction) attachments.

[0025] The prosthetic aortic valve has three leaflets made from a biocompatible material with sufficient flexibility to allow blood to flow in one direction from the inflow end to the outflow end and prevent blood from flowing in the reverse direction by opening and closing the leaflets during systole and diastole.

[0026] The prosthetic aortic valve includes an inner skirt made of a biocompatible material at least partially covering the inner surfaces of the lower row of cells, an outer skirt also made of a biocompatible material at least partially covering the outer surfaces of the lower row of cells, and an outer skirt having excess material to provide slack when the support frame is in a radially expanded state and to reduce slack when the support frame is in a radially contracted state.

[0027] The delivery system includes a balloon catheter consisting of an elongate shaft having a distal end and a proximal end. The distal end of the elongate shaft has an expandable balloon attached thereto, and the proximal end of the elongate shaft has a handle attached thereto. The delivery system also includes other components necessary for a balloon catheter. The distal end is the end away from the operator.

[0028] The portion of the balloon catheter shaft located within the balloon is provided with four radiopaque markers: a distal marker, a proximal marker, a middle marker, and a landing zone marker. The distal marker is located toward the distal end of the balloon, and the proximal marker is located toward the proximal end of the balloon. The middle marker is located equidistant between the proximal and distal markers, and the landing zone marker is located between the distal and middle markers at a specific distance from the distal marker.

[0029] The prosthetic aortic valve and balloon catheter form an assembly. The prosthetic aortic valve is fluoroscopic. When the prosthetic aortic valve is crimped onto the balloon of the balloon catheter between the two stoppers and the two extreme radiopaque markers (i.e., the proximal and distal markers), alternating light and dark areas appear under fluoroscopy. The dark areas are formed by the circumferential extension of rows of diagonal struts, while the light areas are formed by the curved struts or rhombohedrons of the diamond-shaped cells and the commissures.

[0030] The landing zone marker on the delivery catheter is located posterior to the midpoint of the bright area toward the inflow end of the prosthetic aortic valve.

[0031] As described above, the present invention allows for precise positioning and deployment of a prosthetic aortic valve in situ. The first step in the deployment method involves introducing an introducer sheath into the patient's vasculature. Next, a standard angiographic pigtail catheter is passed through the introducer sheath into the patient's vasculature, and its distal tip is positioned at the lowest point of the non-coronary cusp under fluoroscopic guidance.

[0032] Next, a standard recommended guidewire is inserted under fluoroscopic guidance and navigated across the patient's aortic valve orifice.The prosthetic aortic valve, pre-crimped onto the balloon of the delivery catheter, is then introduced through the introducer sheath and navigated under fluoroscopic guidance along the guidewire to the patient's aortic valve orifice.

[0033] Next, the prosthetic aortic valve is accurately positioned in the annular plane by aligning the center of the landing zone marker in the balloon of the delivery catheter with the lowest point of the pigtail and the center of the bright area toward the inflow zone with the lower end of the pigtail. The prosthetic aortic valve is deployed at this position by inflating the balloon of the delivery catheter. After the prosthetic aortic valve is implanted, the balloon of the delivery catheter is deflated and the delivery catheter shaft along with the balloon is withdrawn from the patient's vascular system.

[0034] The above-mentioned and other features and advantages of the present invention will become more apparent from the following detailed description which proceeds with reference to the accompanying drawings.

[0035] The foregoing summary, as well as the following detailed description of exemplary embodiments, can be better understood when read in conjunction with the accompanying figures. For the purpose of illustrating the disclosure, various exemplary embodiments are shown in the figures. However, the disclosure is not limited to the descriptions and figures disclosed herein. Furthermore, those skilled in the art will understand that the figures are not to scale. Wherever possible, like elements have been numbered identically. [Brief explanation of the drawings]

[0036] [Figure 1] FIG. 1 is an exploded view of a frame 101 according to an embodiment of the present disclosure. [Figure 1a] 1 shows a commissure (junction) portion 101d of a frame 101 according to an embodiment of the present disclosure. [Figure 1b] FIG. 1 is an exploded view of a frame 101 according to an embodiment of the present disclosure. [Figure 1c] FIG. 10 is an exploded view of a frame 101 according to another embodiment of the present disclosure. [Figure 1d] 1 shows an exploded view of a frame 101 according to different embodiments of the present disclosure. [Figure 1e] 1 shows an exploded view of a frame 101 according to different embodiments of the present disclosure. [Figure 1f] 1 shows an exploded view of a frame 101 according to different embodiments of the present disclosure. [Figure 1g] 1 shows an exploded view of a frame 101 according to different embodiments of the present disclosure. [Figure 2] 1 shows a valve leaflet 103 according to an embodiment of the present disclosure. [Figure 2a] 1 shows a valve leaflet 103x according to another embodiment of the present disclosure. [Figure 3] 1 shows a prosthetic valve 100 having an inner skirt 105 according to an embodiment of the present disclosure. [Figure 4]1 shows a THV 100 having an outer skirt 107 according to an embodiment of the present disclosure. [Figure 5] 2 shows a delivery catheter 200 according to one embodiment of the present disclosure. [Figure 6] 2 shows an exploded view of a balloon 201 with a support tube 207 according to an embodiment of the present disclosure. [Figure 7] 1 shows a THV 100 implanted in an aortic valve annulus according to an embodiment of the present disclosure. [Figure 8] 1 and 1b shows a schematic representation of a THV 100 fabricated using the frame 101 of FIGS. 1 and 1b mounted over the balloon of a delivery system 200 in a crimped state visible under fluoroscopy, in accordance with an embodiment of the present disclosure. [Figure 9] 1 shows a schematic representation of a THV 100 fabricated with a frame 101 mounted over the balloon of a delivery system 200 in a crimped state visible under fluoroscopy, in accordance with an embodiment of the present disclosure. [Figure 10] 1 shows a schematic representation of the native aortic root complex. [Figure 11] 1 shows a schematic representation of the native aortic root complex. [Figure 12] Methods of implanting a THV 100 according to different embodiments of the present disclosure are disclosed. [Figure 13] 10A-10C are schematic diagrams illustrating the positioning of a THV 100 according to different embodiments of the present disclosure. [Figure 14] 10A-10C are schematic diagrams illustrating the positioning of a THV 100 according to different embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0037] Before describing the present invention, certain words and terms are defined as follows: "Include" and "Comprise" and their derivatives refer to an open-ended inclusion. The term "or" is inclusive, meaning and / or. "Coupled" and "Associated" and their derivatives may mean include, include, interconnect, include, contain, connect or be connected, couple, be in communication with, cooperate with, interleave, juxtapose, adjoin, be connected or associated with, have a characteristic, and the like. Definitions of certain words and terms are provided throughout this application, and one of ordinary skill in the art will understand that these definitions apply to past as well as future uses of these words and terms.

[0038] References throughout this application to "one embodiment," "an embodiment," or similar phrases mean that a particular feature, structure, or characteristic is included in at least one embodiment. Thus, appearances of "in one embodiment," "in an embodiment," and similar phrases throughout this specification do not necessarily all refer to the same embodiment and may mean "one or more, but not all, embodiments," unless expressly specified otherwise. The terms "including," "comprising," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise. Listing of items does not imply that any or all of the items are mutually exclusive and / or mutually inclusive, unless expressly specified otherwise. Terms in the singular may also refer to the plural unless expressly specified otherwise.

[0039] Although the operations of exemplary embodiments of the disclosed method may be described in a particular sequential order for convenience of description, it should be understood that embodiments of the present disclosure may encompass orders of operations other than the particular sequential order disclosed. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Furthermore, descriptions and disclosures provided in connection with a particular embodiment are not limited to that embodiment but may be applicable to any embodiment disclosed herein. Furthermore, Additionally, for the sake of simplicity, the accompanying figures may not show the various ways in which the disclosed systems, methods, and apparatus can be used in combination with other systems, methods, and apparatus.

[0040] Furthermore, the described features, advantages, and characteristics of these embodiments may be combined in any suitable manner. Those skilled in the relevant art will recognize that embodiments can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in all embodiments that are not present in a particular embodiment. The features and advantages of these embodiments will become more fully apparent from the following description and appended claims, or may be learned by the embodiments described hereinafter.

[0041] In the drawings and description herein, the terms "frame" or "stent" or "frame" or "scaffold structure" or "support frame" or "scaffold" refer to the metallic frame of the present invention. These terms are used interchangeably and have the same meaning. The terms "valve" or "prosthetic valve" refer to the prosthetic valve of the present invention, and also refer to a prosthetic valve assembled using a support frame and other components, such as leaflets and a skirt, of animal tissue, and these terms are also used interchangeably. The term "native valve" refers to a natural valve found in a human heart.

[0042] Similarly, the terms "delivery system," "delivery catheter," "catheter," "balloon catheter," and "delivery balloon catheter" refer to delivery devices used in the present invention. These terms are used interchangeably and have the same meaning.

[0043] The present invention provides a balloon-expandable prosthetic heart valve system (or simply, system). The system of the present invention includes a transcatheter prosthetic heart valve (THV) and a THV delivery system. The THV of the present invention can be implanted into a stenosed aortic ostium of a human via catheterization techniques using the THV delivery system. The THV and THV delivery system work in concert to improve the performance of the system.

[0044] The present invention cleverly retains the core prior art of THVs disclosed in the background patents mentioned above, with some improvements: THVs consist of a stretchable and flexible frame, multiple valve leaflets (preferably three leaflets) made of animal tissue or synthetic material, and inner and outer skirts attached to the frame.

[0045] The THV frame of the present invention offers several structural and clinical advantages over conventional frames and mitigates the disadvantages of conventional frames. The THV frame of the present invention is composed of intersecting octagonal cells, with diamond bodies (with or without holes) or diamond cells incorporated at each intersection. This structure increases columnar strength, resulting in improved radial strength and fatigue resistance.

[0046] Unlike conventional transcatheter bioprosthetic valve frames, the frame has two rows of overlapping octahedral cells. The reduced number of rows and the special shape of the cells reduces shrinkage at the front of the frame during radial expansion, making it easier to accurately implant the prosthetic heart valve.

[0047] Furthermore, the delivery system of the present invention facilitates accurate placement and precise deployment of the THV.

[0048] A THV 100 according to an embodiment of the present invention is shown in Figures 3 and 4. Figure 3 shows the THV 100 without an outer skirt 107, and Figure 4 shows the THV 100 with an outer skirt 107. Because the THV100 is implanted into a human's stenotic aortic valve orifice, the THV100 is also called an "artificial aortic valve."

[0049] The frame of the THV100 (also referred to as the "support frame") is radially expandable. The THV100 is suitable for attachment to the balloon of a delivery catheter in a radially contracted state. The balloon delivery catheter, in a contracted state together with the THV100, is advanced to the implantation site, and the THV100 is radially expanded, thereby implanting it into the orifice of a stenotic aortic valve in a human. The THV100 exhibits fluoroscopic properties.

[0050] The THV 100 has an inlet end 100a and an outlet end 100b. Blood enters the THV 100 at the inlet end 100a and exits at the outlet end 100b.

[0051] 3 and 4, the THV 100 includes a frame 101 (or support frame 101), a plurality of valve leaflets 103, an inner skirt 105 (as shown in FIG. 3), and an outer skirt 107 (as shown in FIG. 4).

[0052] Exploded views of two exemplary embodiments of a frame 101 of the present invention are shown in Figures 1, 1b, and 1c. The frame 101 is cylindrical and has an inflow end 100a and an outflow end 100b. The frame 101 is also radially collapsible and radially expandable. The exemplary embodiment frame 101 is balloon expandable and also self-expandable.

[0053] The frame 101 can be formed according to a predetermined method. For example, the frame of the THV 100 can be formed by laser cutting a metal tube. The metal tube can be made from a metal or metal alloy, including, but not limited to, stainless steel, cobalt-chromium alloy, cobalt-chromium-nickel alloy, cobalt-chromium-nickel-molybdenum alloy such as MP35N, nitinol, etc. The material used for the frame 101 can be fluoroscopically compatible. In a preferred embodiment of the present invention, the frame 101 is balloon expandable and made from a tube of cobalt-chromium-nickel-molybdenum alloy. MP35N ensures the THV frame 101's adequate radiointensity, radiopacity, and rapid MRI compatibility.

[0054] In one embodiment, at least the outer surface of the frame 101 can be coated with a titanium niobium nitride (TiNbN) ceramic surface coating, which is highly biocompatible and provides the following benefits: 1.Improved radial strength of the frame. 2.Improved radiolucency of the frame 3.Improved frame fatigue resistance. 4. Reduced allergic reactions due to cobalt and other components of the alloy used in the frame. 5. Advanced surface finish with TiNbN coating provides extremely low roughness average (RA value), minimizing platelet aggregation and potential thrombus and pannus formation.

[0055] The structure of the frame 101 of an exemplary embodiment is shown in Figures 1, 1a and 1b. With respect to Figure 1b, it should be noted that the frame scaffold design is shown flat for convenience only, and that the frame 101 is not necessarily made from a flat metal plate.

[0056] As can be seen from Figures 1 and 1b, the frame 101 includes an inflow end 100a, an outflow end 100b, and a plurality of rows of cells 101b. The cells 101b are predefined 1 and 1b, the frame 101 includes two adjacent rows of octagonal rectangular cells 101b extending between its distal and proximal ends: a lower row of cells 101b1 (towards the inflow end 100a) and an upper row of cells 101b2 (towards the outflow end 100b). In 1 and 1b, the frame 101 includes two adjacent rows of octagonal rectangular cells 101b extending between its distal and proximal ends: a lower row of cells 101b1 (towards the inflow end 100a) and an upper row of cells 101b2 (towards the outflow end 100b).

[0057] 3 and 4, blood enters the THV 100 at the inflow end 100a (also referred to as the "lower end" or "distal end") and exits at the outflow end 100b (also referred to as the "upper end" or "proximal end"). The row of octagonal cells 101b at the inflow end 100a / distal end of the frame 101 is also referred to as the lower row of cells 101b1. The row of octagonal cells 101b at the outlet end 100a / proximal end of the frame 101 is also referred to as the upper row of cells 101b2.

[0058] The embodiment shown in Figures 1 and 1b has two rows of cells, which is fewer than the three rows of cells in the aforementioned patent application. The reduced number of rows and the special shape of the cells 101b reduce contraction of the proximal side of the frame 101 during radial expansion, making it easier for the surgeon to accurately implant the THV 100. Additionally, the use of octagonal cells 101b provides high columnar and radial support to the structure.

[0059] As shown in the frame 101, the cells 101b in the top row 101b2 and the bottom row 101b1 are the same or equal in size. However, frames 101 having cells 101b of different sizes are also within the scope of the present invention. For example, the size of the cells 101b in the frame 101 in the top row 101b2 may be larger or smaller than the size of the cells 101b in the bottom row 101b1.

[0060] The sum of the angles of a polygon is (n-2) x 180°, where n represents the number of sides. Therefore, for an octagon (with eight sides), the sum of the angles is 1080°. Thus, the sum of all angles of the octagonal cells 101b of the frame 101 of the exemplary embodiment is 1080°.

[0061] As can be seen in FIG. 1b, the aforementioned rows of cells 101b1, 101b2 of frame 101 are formed by three rows of circumferentially extending angled struts (also referred to simply as "angled struts") 10a, 10b, and 10c. The rows of circumferentially extending angled struts include a first row of angled struts 10a (or an upper row of angled struts 10a), a second row of angled struts 10b (or a middle row of angled struts 10b), and a third row of angled struts 10c (or a lower row of angled struts 10c). The first row of angled struts 10a is located at the proximal end 100b of frame 101. The third row of angled struts 10c is located at the distal end 100a (or inflow end) of frame 101. The second row of angled struts 10b is disposed between the first row of angled struts 10a and the third row of angled struts 10c.

[0062] In one embodiment, the angle (A) between the two angled struts in the embodiment depicted in Figure 1b is 116°, although it should be noted that this angle can be less than or greater than 116°.

[0063] Each of the circumferentially extending rows of angled struts 10a, 10b, 10c may include an undulating shape having a plurality of peaks "P" and valleys "V", as shown in FIG. 1b. Thus, any two consecutive angled struts in a circumferentially extending row of angled struts 10a / 10b / 10c form either a peak P or a valley V. In FIG. 1b, the peak "P" of an angled strut 10a in the first row faces the valley "V" of an angled strut 10b in the second row. Similarly, the peak P of an angled strut in the second row faces the valley V of an angled strut 10c in the third row. When a peak of an angled strut in one row faces a valley of an angled strut in an adjacent row, they are referred to as corresponding peaks or valleys.

[0064] The rows of circumferentially extending angled struts 10a, 10b, 10c defined above are connected to each other by links to form first and second rows of cells 101b1, 101b2 arranged adjacently on the frame 101. Each link is either a diamond-shaped cell 101c or a solid rhombohedron (101d) with a hole. The top row of cell 101b2 has three rhombohedrons (101d).

[0065] In the embodiment of the framework shown in FIG. 1b, the top row of cells 101b2 is formed by connecting the valleys V of the top row of angled struts 10a with the corresponding peaks P of the middle row of angled struts 10b with links. Each link is either a diamond-shaped cell defined by a pair of bent struts or a solid rhombohedron. A pair of bent struts (s1 / s2 and s3 / s4, as shown in exploded view Y) forms a diamond-shaped cell 101c. Thus, the top row of cells 101b2 includes octagonal cells with alternating rhombohedrons or diamond-shaped cells at each commissure. There are three rhombohedrons 101d, each with four holes evenly spaced 120° from one another. FIG. 1a shows details of an exemplary rhombohedron 101d, with four holes 101d' provided for suturing the commissure tabs of the valve leaflets. The number of holes can be less than four or more than four. In this embodiment, the bottom row of cells 101b1 are formed by connecting the valleys V of the middle row of angled struts 10b with the corresponding peaks P of the bottom row of angled struts 10c with links. Each link is a diamond-shaped cell defined by a pair of bent struts (s1 / s2 and s3 / s4, as shown in exploded view Y) that form a diamond-shaped cell 101c. The interconnection of angled struts 10a / 10b / 10c in one row with those in an adjacent row through such links forms a cellular structure having intertwined octagonal cells 101b and diamond-shaped cells 101c or perforated solid rhombohedrons 101d.

[0066] With respect to FIG. 1c, it should be noted that the frame scaffold design is shown flat for convenience only, and that the frame 101 is not necessarily made from a flat metal plate. In this embodiment, the upper row of cells 101b2 is formed by connecting the valleys "V" of the angled struts 10a in the first row to the corresponding peaks "P" of the angled struts 10b in the second row with links. Each link is defined by a diamond-shaped cell formed by a pair of curved struts or solid rhombohedrons. Thus, the upper row of cells 101b2 includes octagonal cells with alternating rhombohedron or diamond-shaped cells at each commissure (junction). The upper row of cells 101b2 in this embodiment is similar to the upper row of cells in the embodiment of FIG. 1b, with the links consisting of three perforated rhombohedrons 101d and the remaining diamond-shaped cells 101c. In this embodiment, the lower row 101b1 of cells 101b is formed by connecting the valleys "V" of the second row of angled struts 10b to the corresponding peaks "P" of the third row of angled struts 10c by rhombohedrons 101c' without holes. View Z shows a close-up of links 101c and 101c'.

[0067] The exemplary structure described above helps to increase the columnar strength of frame 101, which in turn improves the radial strength and fatigue resistance of frame 101. Details of the interlocking octagons are shown in close-up Y of a portion of frame 101 in FIG. 1b and close-up Z of a portion of frame 101 in FIG. 1c. There are.

[0068] As shown in Figures 1b-1c, the rhomboid cells 101c have an open configuration. That is, each rhomboid cell 101c includes an opening 101c1 surrounded by a pair of curved struts s1 / s2 and s3 / s4. A rhomboid cell 101c with an opening 101c1 is also referred to as an "open rhombohedron" (a rhombohedron with an open structure). A solid rhombohedron is a rhomboid cell without openings (a rhombohedron with a solid structure).

[0069] Those skilled in the art will be able to conceive of numerous alternative frame scaffold structures having various combinations of diamond-shaped cells (101c) and rhombohedrons (101c' / 101d) connecting the angled struts 10a / 10b / 10c. Several exemplary embodiments of frame scaffold structures are described below. In all embodiments described below, the frame scaffold designs are shown in a flat state for convenience, and the frame 101 may not be made from a flat metal sheet.

[0070] In the embodiment of the frame structure shown in FIG. 1d, the top row of cells 101b2 is formed by connecting the valleys V of the top row of angled struts 10a with corresponding peaks P of the middle row of angled struts 10b with links. The links are defined by rhombohedrons 101c' (without holes) or 101d (with holes). Thus, the top row of cells 101b2 includes octagonal cells with alternating rhombohedrons (with or without holes) at each commissure (junction). There are three rhombohedrons 101d, each with four holes evenly spaced 120° apart. The remaining links are rhombohedrons 101c' without holes. In this embodiment, the bottom row of cells 101b1 is formed by connecting the valleys V of the middle row of angled struts 10b with corresponding peaks P of the bottom row of angled struts 10c with links formed by rhombohedrons (101d) without holes.

[0071] Other exemplary embodiments of frame scaffold structures are shown in Figures 1e-1g, with links connecting rows of angled struts in different combinations of rhomboid cells 101c, rhombohedrons without holes 101c', and rhombohedrons with holes 101d.

[0072] For example, in the frame structure of the embodiment of FIG. 1e, the cells in the upper row 101b2 are formed by links 101c, 101c', and 101d, and the cells in the lower row 101b1 are formed by link 101c.

[0073] Another exemplary embodiment frame structure is shown in FIG. 1f, where the cells in the upper row 101b2 are formed by links 101c, 101c', 101d, and the cells in the lower row 101b1 are formed by link 101c'.

[0074] Another exemplary embodiment of the frame structure is shown in FIG. 1g, where the cells in the upper row 101b2 are formed by links 101c, 101c' and 101d, and the cells in the lower row 101b1 are formed by links 101c and 101c'.

[0075] Several other alternative configurations providing diamond-shaped cells 101c and diamond-shaped bodies 101d / 101c' (with or without holes) will be readily realized by those skilled in the art in light of the above disclosure and are within the scope of the teachings of the present invention.

[0076] In all of the above-described embodiments, the top row of cells 101b2 includes three rhombohedrons 101d with holes arranged at a 120° angle relative to each other. These perforated rhombohedrons 101d form commissure attachments with multiple holes 101d1 (shown in FIG. 1a) for suturing the commissures of the leaflets 103 to the frame 101 (discussed below). In a preferred embodiment, each commissure (junction) attachment portion 101d includes four holes 101d1, although it should be noted that the number of holes 101d1 may be more or less than four.

[0077] In one embodiment, at least one radiopaque marker (not shown) may be provided on any of the struts on frame 101, preferably on the curved struts forming rhomboid cell 101c, or on rhomboid body 101c', for easy visualization under fluoroscopy. In a preferred embodiment, at least one radiopaque marker is provided on a strut of rhomboid cell 101c, or on a rhomboid body 101c' located in the bottom row of cell 101b1. In another preferred embodiment, at least one radiopaque marker may be provided on at least one rhomboid body 101c'.

[0078] It is clear that the solid rhombohedron 101c' or 101d has a higher metal content than the open rhombohedron cell 101c. Thus, the rhombohedron cell 101c' / 101d exhibits higher radiopacity than the rhombohedron cell 101c. Higher radiopacity aids in accurate placement of the THV 100, as it is better visualized under fluoroscopy, as described below.

[0079] The THV 100 of the present invention further includes multiple valve leaflets. In one embodiment, the THV 100 includes three valve leaflets. The valve leaflets may be made from a biocompatible material that is flexible enough to allow movement of the valve leaflets. For example, in the present invention, the valve leaflets of a preferred embodiment are made from animal tissue, such as bovine pericardial tissue. Alternatively, the valve leaflets may be formed from a synthetic polymer material.

[0080] Those skilled in the art will appreciate that the leaflets of a prosthetic heart valve function to allow unidirectional blood flow from the inflow end 100a to the outflow end 100b of the THV 100 and prevent reverse blood flow. This is accomplished by opening and closing the leaflets during systolic and diastolic cycles.

[0081] An exemplary embodiment of the structure of the leaflets 103 is shown in Figure 2. As shown, each leaflet 103 in this embodiment can include a body 103' having a relatively straight upper end 103a. In the embodiment shown in Figure 2, there is an apex 103a1. However, there may be cases where the apex 103a1 is absent. The upper edge 103a is kept free for commissure with the corresponding free edge of the other leaflet 103.

[0082] The upper edge 103a of each leaflet 103 may extend to oppositely positioned side tabs (or commissure (coaptation) tabs) marked 103b1, 103b2 on either side of the leaflet 103. Multiple holes may be located in both side tabs 103b1, 103b2 to facilitate suturing. In the embodiment shown in FIG. 2, two vertical rows of holes, marked Y and Z, are provided near the portions of the side tabs 103b1, 103b2 that are closer to the body 103' of the leaflet 103. In one embodiment, each row of holes Y and Z may include four holes (labeled 1, 2, 3, 4). The number of holes may be more or less than four. Similarly, the number of holes in a column may be one or more than two. The holes are used to attach the leaflets 103 to the connecting fabric and / or frame 101 by suturing.

[0083] Each leaflet 103 further includes a lower edge 103c. As shown in the embodiment of FIG. 2, the lower edge 103c can include a wavy shape with optional small straight sections 103c1, 103c2 located at the commissures (junctions) of the lower edge 103c and the side tabs 103b1, 103b2. The wavy lower edge of the leaflet 103 in the preferred embodiment can include a constant radius R. However, the wavy lower edge of the leaflet 103 can have a varying radius. The wavy lower edge of each leaflet 103 can be attached to the inner skirt 105 by known methods, such as suturing.

[0084] Alternatively, the THV 100 can include leaflets 103x as shown in the embodiment of Figure 2a. Figure 2a is the same as the embodiment of Figure 2, except that it has a straight bottom edge 103c' and vertically oriented sides 103c" (as opposed to a wavy bottom edge). 2. The sides 103c" can be vertical or angled relative to the bottom straight edge 103c'. Figure 2a shows an embodiment in which the sides 103c" are not exactly vertical, but are angled relative to the base 103'.

[0085] The leaflets 103 / 103x can be attached to the frame 101 in a predetermined manner. Those skilled in the art are familiar with various methods known in the art for attaching the leaflets to the commissure attachment portions 101d of the frame 101 using one or more support fabrics. One side tab 103b1 / 103b2 of a given leaflet 103 or 103x pairs with one side tab 103b1 / 103b2 of another leaflet 103 or 103x to form a leaflet. The leaflets can then be attached to the commissure attachment portions 101d of the frame 101 using the support fabric to avoid direct tissue contact with the metal of the frame 101. As described above, the lower edge 103c of the leaflet 103 (FIG. 2) can be attached to the inner skirt 105. Similarly, the straight lower edge 103c' and the vertically oriented edge 103c" of the leaflet 103x (FIG. 2a) can also be attached to the inner skirt 105.

[0086] The inner skirt 105 is attached to the inner (or interior) surface of the frame 101 and, in a preferred embodiment, at least partially covers the inner surfaces of the lower row 101b1 of octagonal cells 101b, as shown in Figure 3. The scalloped lower edge 103c or straight lower edge 103c' of the leaflet 103 or 103x is attached to the inner surface of the inner skirt 105. The vertical edges 103c" of the leaflets 103x are also attached to the inner surface of the inner skirt 105. The inner skirt 105 of the preferred embodiment may be made from a fabric such as PET. However, any other biocompatible fabric or animal tissue having the necessary flexibility, strength and porosity can be used to make the inner skirt 105. The inner skirt 105 prevents blood from leaking through the openings in the cells 101b of the frame 101 of the lower row 101b1 and also prevents inadvertent damage to the leaflets 103 / 103x of the THV 100 from calcium spurs present in diseased native valves.

[0087] FIG. 4 shows the outer skirt 107 of a preferred embodiment. The outer skirt 107 has an upper end 107b and a lower end 107a. In one embodiment, the upper end 107b (the outflow end) of the outer skirt 107 may be attached to the inner skirt 105 and the frame 101 by sutures at the midpoint of the frame 101, as shown in FIG. 4. In the same embodiment, the lower end 107a (the inflow end 100a) of the outer skirt 107 is attached to the lower end 105a of the inner skirt 105 by sutures. As is known to those skilled in the art, the function of the outer skirt 107 is to seal the very small passage between the THV 100 and the inner surface of the blood vessel, thereby preventing or minimizing blood leakage between the prosthetic valve and the blood vessel.

[0088] 4 illustrates a preferred embodiment in which an outer skirt 107 is attached to the outer (or exterior) surface of the frame 101 and at least partially covers the outer surface of the lower row 101b1 of octagonal cells 101b. This degree of coverage further aids in minimizing error in positioning the THV 100 around asymmetrical cusp shapes, cusps with heavy calcification, anatomically challenging aortas such as the horizontal aorta, etc. This coverage also reduces the operator's learning curve during placement and deployment.

[0089] The outer skirt 107 of the present invention may be made from a fabric such as PET, however, other biocompatible fabrics or materials, such as animal tissue, that provide the necessary flexibility, strength, and porosity may also be used. Additionally, as shown in FIG. 4, outer skirt 107 has excess material that fits loosely to frame 101 to create slack when frame 101 is in a radially expanded state. The excess material of the loosely fitting outer skirt 107 fills the irregular inner surface of the aortic annulus (which also contains the native valve leaflets), occludes microchannels, and prevents or minimizes paravalvular leakage. The slack is reduced when frame 101 is in a radially contracted state.

[0090] The delivery system, i.e., delivery catheter 200, of the THV 100 of the present invention is described below. FIG. 5 shows an exemplary delivery catheter 200. The delivery catheter 200 is used to deploy the THV 100 into a damaged native valve at a target location. The framework structure of the THV 100 and the delivery catheter 200 of the present invention provide an easy and accurate method for deploying the THV 100 at a target location.

[0091] The delivery catheter 200 shown in Figure 5 is a balloon catheter. Those skilled in the art will be familiar with the structure of balloon catheters used to radially expand balloon-expandable devices such as stents and prosthetic valves. The exemplary delivery catheter 200 includes a proximal end A and a distal end B. The delivery catheter 200 further includes a balloon 201 at its distal end B (shown in Figure 6), an outer shaft 203, an inner shaft 205, a support tube 207, one or more stoppers 209, a handle 211, and a connector 213 at its proximal end.

[0092] The outer shaft 203 is in the form of an elongated outer tube, also referred to as an "elongated shaft." The outer shaft 203 defines an outer lumen through which extends coaxially the inner shaft 205. The inner shaft 205 defines an inner lumen through which a guidewire passes.

[0093] The outer shaft 203 and the inner shaft 205 have respective proximal and distal ends (A and B). The proximal end faces the handle 211, i.e., toward the operator. The opposite end of the balloon 201 is the distal end, away from the operator. The proximal ends of the outer shaft 203 and the inner shaft 205 pass through the handle 211 and are attached to a connector 213. The connector 213 may be a Y-connector having a guidewire exit port 213A and a port 213B for injecting inflation fluid into the catheter 200. The guidewire port 213A communicates with the inner lumen. The inflation fluid port 213B communicates with the annular space between the two shafts 203 and 205. Those skilled in the art will appreciate that this arrangement is commonly found in balloon catheters.

[0094] An exemplary embodiment of balloon 201 is shown in Figure 6. Balloon 201 is attached to the distal end of outer shaft 203. Lumen 205 extends through balloon 201 and terminates at soft tip 215 at the distal-most end of catheter 200. A guidewire (not shown) enters the guidewire lumen at the distal end of soft tip 215 of catheter 200, passes through the lumen, passes through balloon 201, and exits connector 213 at guidewire port 213a.

[0095] The balloon 201 is radially expanded by injecting pressurized inflation fluid into the balloon 201 through the annular space between the outer shaft 203 and the inner shaft 205 .

[0096] In a preferred embodiment, a support tube 207 is attached to the distal end of the outer shaft 203. The support tube 207 extends into the balloon 201, and the inner tube 205 passes coaxially within the support tube 207 (see FIG. 6).

[0097] 6, the support tube 207 includes a proximal end 207a and a distal end 207b. The proximal end 207a is attached to the outer shaft 203. The distal end 207b is a free end that protrudes into the balloon 201.

[0098] The delivery catheter 200 can include at least one stopper made of a resilient, biocompatible material. The preferred embodiment of Figure 6 includes two stoppers: a proximal stopper 209a and a distal stopper 209b. As shown in Figure 6, the proximal stopper 209a and the distal stopper 209b are attached to the outer surface of the support tube 207.

[0099] The proximal stopper 209a and the distal stopper 209b may be spaced apart by a predetermined distance. In a preferred embodiment, the clearance between the distal end of the proximal stopper 209a and the proximal end of the distal stopper 209b is slightly greater than the length of the crimped THV 100. The THV 100 is crimped onto the balloon 201 within this gap. The clearance defined above may vary depending on the length of the crimped THV 100.

[0100] Crimping the THV 100 between the proximal stopper 209a and the distal stopper 209b as described above prevents the THV 100 from slipping off or dislodging from the balloon 201 during insertion of the crimped THV 100 into the patient's vasculature and during manipulation of the THV 100 through tortuous vascular pathways to reach the implant site. The stoppers 209a and 209b also prevent inadvertent valve embolization during balloon expansion. The resilience of the stoppers 209a and 209b creates a lower entry profile at each end, aiding in smoother transition of the THV 100 from the introducer sheath into the patient's aorta and facilitating easy retrieval of the undeployed THV 100. Inflation fluid enters the balloon 201 through the hole 207c in the proximal end 207a of the support tube 207 and also through its free-open distal end 207b. This feature allows the balloon 201 to steadily expand from the distal and proximal ends simultaneously, creating a dogbone that stabilizes the THV 100 during deployment and prevents inadvertent valve embolization.

[0101] Those skilled in the art will readily appreciate that the support tube 207 described above is provided to facilitate accurate placement of the stoppers 209a, 209b and to allow free flow of inflation fluid to the balloon 201. A delivery system without the support tube 207 will also work, in which case the stopper would be located on the inner shaft 205.

[0102] The support tube 207 of the present invention can include multiple radiopaque marker bands (or markers). In a preferred embodiment, the support tube 207 includes four radiopaque marker bands, including a proximal marker band M1, a distal marker band M2, an intermediate marker band M3, and a landing zone marker band M4. If the delivery system 200 does not include a support tube 207, these markers can be provided on the portion of the inner shaft 205 that is located within the balloon 201.

[0103] The above description refers to a particular THV frame scaffold structure 101 having diamond-shaped cells 101c' or octagonal cells 101b intersecting diamond-shaped cells 101c and a particular shaped commissure (junction) 101d. Those skilled in the art will readily appreciate that the concept of providing radiopaque markers (proximal markers, distal markers, intermediate markers, landing zone markers, etc., disclosed below) for accurate in situ placement of the THV 100 can also be applied to frame scaffold structures having cells of any polygonal shape (e.g., diamond, hexagon, etc.).

[0104] As their names suggest, the proximal and distal marker bands M1 and M2 are positioned toward the proximal and distal ends 207a and 207b of the support tube 207, respectively. The intermediate marker band M3 is located between the proximal and distal marker bands M1 and M2 and is equidistant from M1 and M2. In one embodiment, the landing zone marker M4 is positioned between the distal and intermediate marker bands M2 and M3, approximately 32-33% of the distance between the proximal and distal markers M1 and M2. That is, dimension B is 32-33% of dimension A, and is positioned as shown in FIG. 6.

[0105] The landing zone marker M4 serves as a guide for accurately positioning the THV 100 at the implantation site to achieve implantation in the most favorable position, i.e., the original position. Accurate positioning of the THV 100 can be achieved without the landing zone marker M4, as described below.

[0106] The distal end of the shaft of the exemplary catheter 200 is configured to bend in a controlled manner to facilitate passage through the aortic arch. In alternative embodiments, the distal end of the shaft of the catheter 200 may not be configured to bend. In yet another alternative embodiment, the distal end of the shaft of the catheter 200 is pre-shaped with a fixed radius to facilitate passage through the aortic arch. Pre-shaping the catheter shaft can be achieved by known methods, such as heat treatment.

[0107] The following description pertains to aortic valve replacement.

[0108] In aortic valve replacement, accurate placement and precise deployment of the prosthetic valve are crucial to achieving optimal performance. Optimal performance refers to reducing the transvalvular pressure difference (sustainable hemodynamics), preventing paravalvular regurgitation, and avoiding iatrogenic damage to the conduction system (which would require implantation of a new permanent pacemaker). In aortic valve replacement, the ideal implantation position for the prosthetic valve is, in principle, the midline position, attempting to align the prosthetic annulus (neoprosthetic annulus) with the native annulus. Implanting the prosthetic valve in this position has three important advantages:

[0109] One advantage of placing a prosthetic valve in situ is the ease of anatomical placement of the prosthetic valve. The native valve annulus and its leaflets may be stenotic and calcified. In situ expansion of a prosthetic valve sized to the native annulus securely fixes the frame within the stenotic annulus with its calcified leaflets, providing anatomical fixation that eliminates the risk of embolism due to prosthetic valve dislodgement.

[0110] The second benefit of placing a prosthetic valve in its native position is minimal valve protrusion into the left ventricle. It is important to implant the prosthetic valve in the annulus and not deeply implant it on the ventricular side, i.e., in the subannular position, due to the presence of two critical anatomical regions below the aorta. The first region is the membranous septum between the atria and ventricles, which contains the dense cardiac conduction muscle (the atrioventricular node) that conducts electrical impulses to maintain a normal heartbeat. Ensuring that the prosthetic valve does not locate within the left ventricular outflow tract (LVOT) is important to reduce the risk of disrupting the cardiac conduction system. The second region is the aortic-mitral curtain, located posterolateral to the aortic valve, and the native mitral valve. An incorrectly positioned prosthetic valve may interfere with the normal function of the anterior mitral valve leaflet, potentially affecting mitral valve function. The THV100, implanted using this recommended method, minimizes prosthetic valve protrusion in the left ventricular outflow tract. 7 is a schematic diagram of the aortic root complex (described in more detail below). In one embodiment, as shown in FIG. 7, 80% to 85% of the length of the expanded THV 100 remains above the aortic annulus, and the remaining 15% to 20% is within the subvalvular space, which is the imaginary annular plane 6. stay.

[0111] A third advantage of placing a prosthetic valve in situ is minimizing occlusion of the coronary artery origins, as shown in Figures 3 and 4. The coronary artery origins may be located along the coronary sinus of Valsalva or above the transitional portion of the origin. Ideally, the prosthetic valve does not impede blood flow to the coronary arteries by occluding or maintaining occlusion at the ostia of these arteries. Accurate placement of the THV 100 in situ prevents this by minimizing protrusion of the frame 101 into the ascending aorta. In the present invention, the short height of the THV 100 frame after deployment and the large uncovered cells at the outflow end further avoid occlusion of the coronary artery ostia (3 and 4).

[0112] As shown in Figures 1b-1g, the frame 101 of the THV 100 has three rows of circumferentially extending angled struts 10a, 10b, 10c, each of which has a diamond-shaped cell 101c, a diamond-shaped body 101c', and three rows of angled struts 10a, 10b, 10c interconnected by commissures (junctions) 101d. The THV 100 is crimped onto the balloon 201 between two stoppers 209a, 209b and two distal radiopaque markers M1, M2. Under fluoroscopy, the frame 101 of the THV 100 shown in Figures 1 and 1b, when crimped onto the balloon 201, exhibits alternating light and dark regions (LA) and DA, as shown in Figure 8. The dark area DA is formed by the circumferentially extending rows of angled struts (10a, 10b, 10c), and the light area LA is formed by the commissures (junctions) (101d) formed by the combination of curved struts (s1 / s2 / s3 / s4) of diamond-shaped cells (101c) and octagonal cells (101b). When the THV 100 is crimped onto the balloon 201 of the delivery system 200 between the two stoppers 209a, 209b and the extremely radiopaque markers M1, M2, the landing zone marker M4 is located posterior to the midpoint of the first light area toward the inflow end 100a of the THV 100, as shown schematically in Figure 8, which illustrates an embodiment of the frame 101 and Figure 101b.

[0113] In the embodiment shown in Figure 1c, the bottom row 101b1 of cells 101b includes rhombohedrons 101c', which provide relatively higher radiolucency than the diamond-shaped cells 101c. Thus, the light area (LA) toward the inflow end 100a of the crimped frame 101 is relatively darker than the LA formed by the diamond-shaped cells 101c, making it more easily discernible under fluoroscopy, as shown in Figure 9.

[0114] Another embodiment of the support frame shown in FIGS. 1c-1gg forms LA and DA similar to those shown in FIGS.

[0115] Figure 10 shows the aortic root complex 1. The aortic root is the first dilated portion attached to the distal end of the aorta. It is the portion of the ascending aorta (AA) 2 that contains the native aortic valve. A native aortic valve typically has three cusps. Coronary arteries arise from two of the three cusps near the aortic bulb. The right coronary artery (RCA) 3 ideally arises from the right coronary cusp (RCC), and the left coronary artery (LCA) 4 ideally arises from the left coronary cusp (LCC). The remaining cusp is called the "non-coronary cusp" (NCC) because no coronary arteries arise near it. There are two distinct interfaces: the virtual annular plane (VAP) 6 and the aortic root transition zone (SJ) 7. During standard fluoroscopic imaging, the native coronary valve cusps are coplanar. At this time, the hinge points of each cusp are aligned in a straight line, and all three cusps are well separated. The VAP6 obtained in this way can be confirmed under fluoroscopy and serves as a guide for optimal placement of the prosthetic valve for implantation.

[0116] During THV replacement, under fluoroscopy, the three native coronary artery cusps (sinuses) RCC, LCC, The NCCs are visually aligned in a coplanar view with the non-coronary cusp (NCC) on the patient's right side, the left coronary cusp (LCC) on the patient's left side, and the right coronary cusp (RCC) in the center. This is shown schematically in Figure 11. Note that the fluoroscopic image is a mirror image of the anatomical / AP true image. Therefore, in the schematic view of Figure 11, the NCC appears to the patient's right and the LCC appears to the patient's left.

[0117] Figure 12 illustrates a method for accurately positioning and stepwise deploying the prosthetic aortic valve 100 in the annular plane, i.e., in situ, using a delivery catheter 200. Figures 13 and 14 show schematics of the implantation position. Figure 13 shows the THV 100 crimped onto the balloon 201 of the catheter 200 shown in Figure 8 (corresponding to the frame shown in Figure 1b). Figure 14 shows the THV 100 crimped onto the balloon 201 of the catheter 200 shown in Figure 9 (corresponding to the frame shown in Figure 1c). These frame structures are shown only to illustrate the implantation method. This method can also be applied to the other frame structures mentioned above.

[0118] A person skilled in the art of percutaneous heart valve implantation typically inserts an introducer sheath into the patient's vasculature in step 301. Then, in step 303, under fluoroscopic guidance, a standard angiographic pigtail catheter 8 (preferably 5F size) is inserted and guided through the introducer sheath into the patient's vasculature, with its distal end implanted at its lowest point within the NCC (note that the NCC is typically the lowest reference cusp, lacking the origin of the coronary arteries). This is shown in Figures 13 and 14, where the curved distal end 8a of the pigtail catheter 8 is positioned within the NCC. In step 305, a standard recommended guidewire 9 is inserted under fluoroscopic guidance and guided past the patient's aortic valve orifice.

[0119] Injection of saline diluted contrast through the pigtail catheter 8 allows the operator to visualize the aortic root 1. The VAP is determined as an imaginary line 6 connecting the low points of the aortic root 1 (see Figure 10).

[0120] In step 307, the THV 100 of the present invention, pre-crimped onto the delivery catheter 200, is inserted, guided, and directed across the patient's aortic valve orifice over a standard recommended guidewire under fluoroscopic guidance.

[0121] In step 309, for accurate positioning of the THV 100 in the annular plane, the center of the landing zone marker M4 in the balloon 201 of the THV delivery system 200 must coincide with the lower end 8a of the pigtail 8 located within the lowest part of the NCC (identifying the VAP 6), as shown in FIGS. 13 and 14 . In other words, the center of the landing zone marker M4 coincides with the VAP 6. In the absence of the landing zone marker M4, accurate positioning of the THV 100 in the annular plane is achieved by aligning the center of the LA toward the distal end of the frame 101 with the lower end 8a of the pigtail 8 located within the lowest part of the NCC (identifying the VAP 6). Therefore, the landing zone marker M4 is not absolutely necessary but serves only as a guide to facilitate accurate positioning. The THV 100 is coaxial with the virtual annular plane 6 and therefore adjacent to the pigtail 8 as visualized under fluoroscopy. This ensures that the THV 100 reaches the desired position before deployment. This can be achieved by simultaneous injection of saline-diluted contrast under fluoroscopy.

[0122] Alternatively, or in combination, the THV 100 can be positioned so that the center of the light area (LA) toward the inlet end 100a coincides with either the lower end 8a of the pigtail 8 located within the bottom of the NCC, or with the VAP 6, as shown in Figures 13 and 14.

[0123] Once the above annular position is achieved, the heart is then repositioned using standard known techniques in step 311. The THV100 can be deployed by balloon inflation while rapidly pacing. The previously mentioned two-row octagonal cell shape of the present invention allows for accurate midline deployment through expansion of the frame 101 and the associated low foreshortening. Because the THV100 has a small number of cell rows and a frame scaffold structure, the foreshortening rate is low, improving deployment accuracy.

[0124] Rapid pacing is discontinued after deployment of the THV 100. In step 313, the balloon 201 is quickly deflated and the catheter 200 is withdrawn from the deployed THV 100, which is then removed from the patient in step 315. The guidewire and pigtail catheter are then similarly removed using standard techniques.

[0125] The description of the preferred embodiment of the present disclosure provides illustration and description, but is not intended to be exhaustive or to limit the disclosure to the particularly disclosed form. Modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosure.

[0126] For example, a frame may include two or more rows of overlapping octagonal cells formed by multiple circumferentially extending rows of angled struts. In such cases, the frame may include a top row of angled struts at the upper end of the frame, a bottom row of angled struts at the lower end of the frame, and multiple intermediate rows of angled struts therebetween. The bottom row of struts is positioned toward the inflow end of the support frame. Furthermore, in such embodiments, the top row is referenced relative to the adjacent lower row, which will be referred to as the lower row.

[0127] In the above example, the row of circumferentially extending angled struts may have a wave shape in which two consecutive angled struts in the row of circumferentially extending angled struts form a peak or a valley, with the peak of the upper row of angled struts pointing towards the valley of the adjacent lower row of angled struts.

[0128] Adjacent rows of circumferentially extending angled struts are connected to one another to form a support frame including a plurality of adjacently disposed rows of cells between a proximal end and a distal end, the plurality of adjacently disposed rows of cells including a top row of cells and a bottom row of cells.

[0129] The valleys of the angled struts in the top row are connected to the corresponding peaks of the angled struts in the adjacent bottom row by links (rhomboidal cells or rhombohedrons), forming rows of cells containing intertwined octagonal cells. This results in alternating rhombohedrons or rhomboidal cells at each commissure (junction). The rhombohedrons may have solid interiors, while the rhomboidal cells have open interiors. The top row of cells may contain three rhombohedrons, which are angularly arranged relative to one another to form three commissure (junction) attachments. The rhombohedrons may have holes.

[0130] Various arrangements of the links in different cell rows are possible, resulting in multiple embodiments of the support frame.

[0131] Such prosthetic valves may further include leaflets, an inner skirt, and an outer skirt, similar to the prosthetic valves described above.

[0132] Such a frame provides the necessary columnar strength. The method of deploying such a stent is also modified accordingly to properly position the stent using a corresponding delivery system.

[0133] The scope of the present invention is limited only by the appended claims. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are exemplary only, and that the actual parameters, dimensions, materials, and / or configurations will vary depending on the particular application or uses for which the teachings of the present invention are used.

Claims

1. A radially expandable and collapsible prosthetic aortic valve (100) adapted to be mounted in a radially collapsed state on a balloon of a delivery system, comprising: The prosthetic aortic valve (100) comprises a radially foldable and deployable support frame (101) having a distal end (100a), a proximal end (100b) and three rows of circumferentially extending angled struts (10a, 10b, 10c), the three rows of circumferentially extending angled struts (10a, 10b, 10c) including an upper row of angled struts (10a) at the proximal end (100a) of the support frame (101), a lower row of angled struts (10c) at the distal end (100b) of the support frame (101), and a middle row of angled struts (10b) located between the upper row of angled struts (10a) and the lower row of angled struts (10c), the lower row of angled struts (10c) being located at the inflow end (100b) of the support frame (101); the three rows of circumferentially extending angled struts (10a, 10b, 10c) have a wave-like shape in which every two consecutive angled struts form a peak or a valley, the peaks of the angled struts (10a) in the upper row facing the valleys of the angled struts (10b) in the middle row, and the peaks of the angled struts (10b) in the middle row facing the valleys of the angled struts (10c) in the lower row; adjacent rows of the three circumferentially extending angled struts (10a, 10b, 10c) are interconnected to form a support frame (101) comprising two adjacently disposed rows of cells (101b) between the distal end (100a) and the proximal end (100b); the valleys of the upper row of angled struts (10a) are connected by links to corresponding peaks of the middle row of angled struts (10b), each link forming a rhomboid cell (101c) or a rhombohedron (101d / 101c') to form a cell row (101b2) comprising intersecting octagonal cells, the rhombohedrons (101d / 101c') or rhomboid cells (101c) being alternately arranged at each commissure, the rhombohedrons (101d / 101c') having a solid internal structure and the rhomboid cells (101c) having an open internal structure; the valleys of the middle row of angled struts (10b) are connected by links to corresponding peaks of the lower row of angled struts (10c), each link forming a rhomboid cell (101c) or a rhombohedron (101d / 101c') to form a row of cells (101b1) comprising intersecting octagonal cells adjacent to an upper row of cells (101b2) comprising intersecting octagonal cells, the rhomboid cells (101c) or rhombohedrons (101d / 101c') being alternately arranged at each commissure, the rhomboid cells (101c) having an open structure and the rhombohedrons (101d / 101c') having a solid structure; The lower row of cells (101b1) is located at the inlet end (100b) of the support frame (100), and the upper row of cells (101b2) is located at the outlet end (100a) of the support frame (101); the upper row of cells (101b2) is composed of three rhombohedrons, the three rhombohedrons being arranged at angles to each other and forming three commissure attachment portions (101d) to which leaflet tabs (103) are attached, and the three rhombohedrons (101d) are drilled with holes (101d1); The prosthetic aortic valve (100) further comprises three valve leaflets (103) made of a biocompatible material that are flexible enough to allow blood to flow unidirectionally from the inflow end to the outflow end of the prosthetic aortic valve (100) and to provide sufficient movement to open and close the leaflets (103) to prevent blood from flowing in the reverse direction; The prosthetic aortic valve (100) further comprises an inner skirt (105) made of a biocompatible material, the inner skirt (105) at least partially covering the inner surfaces of the lower row of cells (101b1); The prosthetic aortic valve (100) further comprises an outer skirt (107) made of a biocompatible material. wherein the outer skirt (107) at least partially covers the outer surfaces of the lower row of cells (101b1).

2. 2. The prosthetic aortic valve (100) of claim 1, wherein the cells of the upper row of cells (101b2) and the cells of the lower row of cells (101b1) of the support frame (101) are the same size.

3. 2. The prosthetic aortic valve (100) of claim 1, wherein the cells of the upper row of cells (101b2) of the support frame (100) are larger or smaller in size than the cells of the lower row of cells (101b1).

4. 2. The prosthetic aortic valve according to claim 1, wherein each link of the support frame other than the three perforated rhombohedrons of the upper row of cells is a rhombohedron or a rhombohedron without a hole (101c'), and each link of the lower row of cells is at least one of a rhombohedron or a rhombohedron without a hole (101c').

5. 2. The prosthetic aortic valve (100) of claim 1, wherein the links of the support frame (101) other than the three perforated rhombohedrons (101d) of the upper row of cells (101b2) are rhombohedrons (101c'), and all links of the lower row of cells (101b1) are rhombohedrons (101c).

6. 2. The prosthetic aortic valve (100) of claim 1, wherein the links of the support frame (100) other than the three perforated rhombohedrons (101d) of the upper row of cells (101b2) are rhombohedrons (101c'), and all links of the lower row of cells (101b1) are rhombohedrons (101c).

7. 2. The prosthetic aortic valve (100) of claim 1, wherein all links of the upper row of cells (101b2) and the lower row of cells (101b1) of the support frame (101) other than the three perforated rhombohedrons (101d) of the upper row of cells (101b2) form a rhombohedron (101c').

8. 2. The prosthetic aortic valve (100) of claim 1, wherein all links of the upper row of cells (101b2) and the lower row of cells (101b1) of the support frame (101) other than the perforated rhombohedrons (101d) of the upper row of cells (101b2) are rhomboid cells (101c).

9. 2. The prosthetic aortic valve of claim 1, wherein each leaflet has a relatively straight upper end with or without an apex, one commissure tab on each leaflet on either side of the upper end, and a wavy lower end attached to the inner skirt, the upper end remaining free for the commissures.

10. 2. The prosthetic aortic valve of claim 1, wherein the leaflets have a relatively straight upper end with or without an apex, one commissure tab on each leaflet on either side of the upper end, and a straight lower end and two side ends attached to the inner skirt, the upper end remaining free for commissures.

11. The biocompatible material for the valve leaflets (103) includes animal tissue, and the leaflets (103) are 2. The prosthetic aortic valve according to claim 1, wherein the commissure tabs are attached to the support frame directly or via an intermediate fabric layer to prevent direct contact between the animal tissue and the metal of the support frame.

12. The prosthetic aortic valve (100) of claim 11, wherein the animal tissue comprises bovine pericardium.

13. 10. The prosthetic aortic valve (100) of claim 1, wherein the biocompatible material for the valve leaflets (103) is a biocompatible synthetic polymeric material.

14. The prosthetic aortic valve (100) of claim 13, wherein the synthetic polymer material comprises a fabric.

15. 10. The prosthetic aortic valve (100) of claim 1, wherein at least one of the inner skirt (105) and the outer skirt (107) is made of fabric or animal tissue.

16. 10. The prosthetic aortic valve (100) of claim 1, wherein the support frame (101) is made of a fluoroscopic material.

17. 10. The prosthetic aortic valve (100) of claim 1, wherein the support frame (100) is made of a metal or metal alloy.

18. 18. The prosthetic aortic valve (100) of claim 17, wherein the alloy comprises either a cobalt-chromium-nickel alloy or a cobalt-chromium-nickel-molybdenum alloy MP35N.

19. 2. The prosthetic aortic valve of claim 1, wherein the outer skirt includes excess material, causing slack in the outer skirt when the support frame is in a radially expanded state and reducing slack when the support frame is in a radially contracted state.

20. 2. The prosthetic aortic valve (100) of claim 1, wherein the commissure attachments (101d) are disposed at an angle of 120 degrees to each other.

21. 1. A prosthetic aortic valve that is radially expandable and collapsible and adapted to be mounted on a balloon of a delivery catheter in a radially collapsed state, comprising: the prosthetic aortic valve comprises a radially foldable and expandable support frame having a distal end, a proximal end, and three rows of circumferentially extending angled struts, the three rows of circumferentially extending angled struts including an upper row of angled struts at the proximal end of the support frame, a lower row of angled struts at the distal end of the support frame, and a middle row of angled struts located between the upper and lower row of angled struts, the lower row of angled struts being on the inflow end of the support frame; the three rows of circumferentially extending angled struts are undulating in shape, with any two consecutive circumferentially extending angled struts in a row forming a peak or a valley, with the peak of an angled strut in an upper row facing the valley of an angled strut in an adjacent lower row; adjacent rows of the three circumferentially extending angled struts are connected to one another to form the support frame, the support frame including a plurality of adjacently disposed rows of cells between the distal end and the proximal end, the plurality of adjacently disposed rows of cells consisting of an upper row of cells and a lower row of cells; The valleys of the upper row of angled struts are connected by links to the adjacent lower row of angled struts. each link is connected to a corresponding peak of the link, and each link forms a rhomboid cell or a rhombohedron, and a row of cells is formed in which the rhomboid cells and the rhombohedrons are alternately arranged, the rhombohedrons having a solid structure and the rhomboid cells having an open structure; a top row of cells comprised of three rhombohedrons, the three rhombohedrons being angularly disposed relative to one another to form three commissure attachments, the three rhombohedrons being perforated; the prosthetic aortic valve further comprises three leaflets made of a biocompatible material that allows unidirectional blood flow from the inflow end to the outflow end of the prosthetic aortic valve and provides sufficient flexibility to prevent reverse blood flow by opening and closing the leaflets, each leaflet having at least two commissure tabs to which the support frame is attached at the commissure attachment portion; the prosthetic aortic valve further comprises an inner skirt made of a biocompatible material, the inner skirt at least partially covering the inner surfaces of the lower row of cells; The prosthetic aortic valve further comprises an outer skirt made of a biocompatible material, the outer skirt at least partially covering an outer surface of the lower row of cells.

22. A delivery catheter (200) having a proximal end (A) and a distal end (B), an elongated shaft (203) having a distal end and a proximal end; an inflatable balloon (201) connected to the distal end of the elongated shaft (203) (the distal end being the end away from the operator), and a handle (211) connected to the proximal end of the elongated shaft (203); a plurality of opaque markers disposed on a portion of the elongated shaft (203), the plurality of opaque markers including at least a distal marker (M2), a proximal marker (M1), a middle marker (M3), and a landing zone marker (M4); A delivery catheter (200) wherein the distal marker (M2) is positioned on the distal end side of the balloon (201), the proximal marker (M1) is positioned on the proximal end side of the balloon (201), the intermediate marker (M3) is positioned midway between the proximal marker (M1) and the distal marker (M2) and is equidistant from the proximal marker (M1) and the distal marker (M2), and the landing zone marker (M4) is positioned between the distal marker (M2) and the intermediate marker (M3).

23. 23. The delivery catheter (200) of claim 22, wherein the landing zone marker (M4) is positioned from the distal marker (M2) at a distance of approximately 32-33% of the distance between the proximal marker (M1) and the distal marker (M2).

24. A prosthetic aortic valve (100) according to any one of claims 1 to 20; 24. An assembly comprising: a delivery catheter (200) according to claim 22 or 23; the prosthetic aortic valve (100) has fluoroscopy and, when crimped onto the balloon (201) of the delivery catheter (200), exhibits alternating light and dark regions under fluoroscopy; the dark regions are formed by circumferentially extending rows of angled struts (10a, 10b, 10c) and the light regions are formed by links and commissure attachments (101d) formed by rhomboid cells (101c) or rhombohedrons (101c'); An assembly wherein the landing zone marker (M4) of the delivery catheter (200) is positioned behind the midpoint of the bright area toward the inflow end of the prosthetic aortic valve (100).

25. A method for accurately positioning and deploying a prosthetic aortic valve (100) in an annular plane in an orthotopic position using a delivery catheter (200), comprising: introducing an introducer sheath into the patient's vascular system; introducing a standard angiographic pigtail catheter (8) into the patient's vasculature through an introducer sheath and positioning its distal end at its lowest point within the NCC under fluoroscopic guidance; introducing a guidewire (9) under fluoroscopic guidance through the aortic opening of the patient; introducing the prosthetic aortic valve (100) of claim 1, pre-crimped onto the balloon (201) of the delivery catheter (200) of claim 23, through the introducer sheath and guiding it over the guidewire (9) under fluoroscopic guidance to the aortic opening of the patient; a step of accurately positioning the prosthetic aortic valve (100) on the annular plane by aligning the center of a landing zone marker (M4) in the balloon (201) of the delivery catheter (200) with the lower end of the pigtail catheter (8) and aligning the midpoint of the bright area toward the inflow end with the lower end of the pigtail catheter (8); deploying the prosthetic aortic valve (100) at the location by expanding the balloon (201) of the delivery catheter (200); and withdrawing the elongate shaft (203) of the delivery catheter (200) along with the balloon (201) from the patient's vasculature.

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