Prosthetic Heart Valve

Description

1 / 42 Prosthetic Heart Valve Request for division of BR112019023310-5 dated 05 / 31 / 2018.

[0001] This patent application is a division of BR 11 2019 023310 5, filed on 05 / 31 / 2018. FIELD

[0002] The present invention description relates to implantable and expandable prosthetic devices and to methods and apparatus for such prosthetic devices. FUNDAMENTALS

[0003] The human heart can suffer from various valvular diseases. These valvular diseases can result in significant heart malfunction and ultimately require the replacement of the native valve with an artificial valve. There are a number of known artificial valves and several known methods of implanting these artificial valves in humans. Due to the disadvantages associated with conventional open-heart surgery, percutaneous and minimally invasive surgical approaches are receiving intense attention. In one technique, a prosthetic valve is configured to be implanted in a much less invasive procedure via catheterization. For example, compressible transcatheter prosthetic heart valves can be pinched to a compressed state and introduced percutaneously in the compressed state into a catheter and expanded to a functional size in the desired position by balloon inflation or by using a self-expanding frame or stent.

[0004] A prosthetic valve for use in such a procedure may include a radially retractable and expandable structure to which the leaflets of the prosthetic valve may be attached. For example, US Patents Nos. 6,730,118, 7,393,360, 7,510,575 and 7,993,394 describe exemplary foldable transcatheter heart valves (THVs).

[0005] A challenge in catheter-implanted prosthetic valves is the process of crimping a prosthetic valve into a profile suitable for percutaneous administration to an individual. Another challenge is the control of paravalvular leakage around the valve, which can occur for a period of time after initial implantation.

[0006] Paravalvular leakage has been a known problem since the introduction of the first replacement valves. Older prosthetic heart valves, Petition 870260077472, dated 04 / 08 / 2026, page 12 / 91 2 / 42 of those that were surgically implanted included a circumferential suture ring that was adapted to extend into spaces in the tissue surrounding the implanted prosthesis to prevent paravalvular leaks. For example, US Patent No. 3,365,728 describes a prosthetic heart valve for surgical implantation that includes a rubber cushioning ring that adapts to tissue irregularities to form an effective seal between the valve and surrounding tissue. From there, vascular stents or stent grafts were developed that could be implanted by non-surgical catheterization techniques. These stents included a tissue covering that allowed the stent to be used to isolate and reinforce the wall of a blood vessel from the vessel lumen.These tissue coverings served essentially the same purpose in stents as the O-rings in surgical heart valves; they reduced the risk of blood leakage between the prosthesis and the surrounding tissue. Several graft designs were developed that further improved the external seal to prevent blood flow between the graft and the surrounding cardiovascular tissue. For example, US Patent No. 6,015,431 by Thornton describes a seal attached to the outer surface of a stent that is adapted to obstruct leakage flow externally around the stent wall between the outer surface and the endoluminal wall when the stent is implanted, by adapting to the irregular surface of the surrounding tissue. US Patent Publication 2003 / 0236567 by Elliot similarly describes a tubular prosthesis having a stent and one or more tissue skirts to seal against internal leaks. US Patent Publication 2004 / 0082989 by Cook et al.He also acknowledged the potential for internal leaks and described a stent graft with a cuff portion that has an external sealing zone extending around the stent body to prevent leaks. The cuff portion can be folded to create a pocket that collects any blood that passes around the leading edge of the graft to prevent an internal leak.

[0007] Based on this technology, in the late 1980s, the first permanent bioprosthetic heart valve was implanted using transcatheter techniques. Andersen's US patent 5,411,552 describes a THV comprising a valve mounted within a foldable and expandable stent structure. Certain designs have additional graft material used along the outer and inner surfaces of the THV. As with stent grafts, the proposed coverings for use with Petition 870260077472, dated 04 / 08 / 2026, page 13 / 91 3 / 42 THVs were designed to conform to the surface of the surrounding tissue in order to prevent paravalvular leaks.

[0008] As with stents, cuffs or other external seals have been used in THVs. Bessler's US patent 5,855,601 describes a self-expanding THV with a cuff portion that extends along the outside of the stent. After compression of the stent for delivery, the external seal folds to form folds and then expands with the stent to provide a seal between the THV and the surrounding tissue.

[0009] Subsequently, a different THV design was described by Pavcnik in US Patent Application Publication 2001 / 0039450. Pavcnik's improved sealing structure is in the form of corner flaps or pockets attached to the stent at the edges of each flap or pocket and positioned in discreet locations around the prosthesis. The corner flap is designed to capture retrograde blood flow to provide a better seal between the THV and the vessel wall, as well as providing an improved substrate for the ingrowth of native tissue.

[0010] Thus, tissues and other materials used to cover and seal internal and external surfaces of THVs and other endovascular prostheses, such as stents and stent grafts, are well known. These coverings can be made with low-porosity tissue materials, as described, for example, by US patent 5,957,949 by Leonhardt et al., which describes a valve stent with an outer covering that can adapt to the surrounding living tissue after implantation to help prevent blood leakage.

[0011] Several more recent THV designs include a THV with an outer cover. Spenser's US patent 7,510,575 describes a THV with a cuff portion wrapped around the outer surface of the supporting stent at the inlet. The cuff portion is wrapped over the edge of the frame so as to provide a glove-like portion at the inlet to form a cuff over the inlet that helps prevent blood leakage. Letac and Cribier's US patent 8,002,825 describes an inner cover that extends from the base of the valve to the lower end of the stent and then to the outer wall of the stent so as to form an outer cover. The one-piece cover can be made with any of the materials described for the manufacture of the valve structure, which includes fabric (e.g., Dacron), biological material (e.g., pericardium), or Petition 870260077472, dated 04 / 08 / 2026, p. 14 / 91 4 / 42 other synthetic materials (e.g., polyethylene).

[0012] Although the coverings used on the outer surface of an endovascular prosthesis to prevent paravalvular leaks are well known, there continues to be a need for improved coverings that provide enhanced sealing while also providing a small profile suitable for percutaneous delivery to the patient. SUMMARY

[0013] Embodiments of a radially foldable and expandable prosthetic valve are described in this document which include an enhanced outer skirt to reduce perivalvular leakage, as well as related methods and devices, including these prosthetic valves. In several embodiments, the described prosthetic valves are configured as replacement heart valves for implantation in a patient.

[0014] In a representative embodiment, a prosthetic heart valve comprises an annular structure comprising an inlet end and an outlet end and is radially compressible and expandable between a radially compressed configuration and a radially expanded configuration. The prosthetic heart valve further includes a leaflet structure positioned within and attached to the structure, and an external sealing element mounted outside the structure and adapted to seal against surrounding tissue when the prosthetic heart valve is implanted within a patient's native heart valve ring. The sealing element may comprise a mesh layer and a hair layer comprising a plurality of hair strands extending outward from the mesh layer.

[0015] In some embodiments, the mesh layer comprises a knitted or woven fabric.

[0016] In some forms, the hair strands are arranged to form a circle.

[0017] In some styles, the hair strands are arranged to form a hair in a circle.

[0018] In some forms, the height of the hair strands varies along a height and / or circumference of the outer skirt.

[0019] In some forms, the hair strands comprise a first Petition 870260077472, dated 04 / 08 / 2026, p. 15 / 91 5 / 42 group of yarns along an upstream portion of the outer skirt and a second group of yarns along a downstream portion of the outer skirt, wherein the yarns of the first group have a height that is less than the height of the yarns of the second group.

[0020] In some embodiments, the hair strands comprise a first group of strands along an upstream portion of the outer skirt and a second group of strands along a downstream portion of the outer skirt, wherein the strands of the first group have a height that is greater than the height of the strands of the second group.

[0021] In some embodiments, the hair strands comprise a first group of strands along an upstream portion of the outer skirt, a second group of strands along a downstream portion of the outer skirt, and a third group of strands between the first and second groups of strands, wherein the strands of the first and second groups have a height that is greater than the height of the strands of the third group.

[0022] In some embodiments, the prosthetic heart valve further comprises an inner skirt mounted on an inner surface of the structure, the inner skirt having an inlet end portion that is attached to an inlet end portion of the outer sealing element.

[0023] In some embodiments, the inlet end portion of the inner skirt is wrapped around an inlet end of the structure and overlaps the inlet end portion of the outer sealing element on the outside of the structure.

[0024] In some embodiments, the mesh layer comprises a first mesh layer and the outer sealing element further comprises a second mesh layer arranged radially outside the pile layer.

[0025] In some embodiments, the external sealing element is configured to stretch axially when the frame is radially compressed to the radially compressed state.

[0026] In some embodiments, the mesh layer comprises warp yarns and weft yarns woven with the warp yarns, and the pile layer comprises the warp yarns or the weft yarns of the mesh layer that are woven or knitted to form the pile yarns.

[0027] In some embodiments, the mesh layer comprises a fabric layer and the hair layer comprises a separate hair layer that is sewn to the fabric layer. Petition 870260077472, dated 04 / 08 / 2026, p. 16 / 91 6 / 42

[0028] In some embodiments, the mesh layer has a first height that extends axially along the structure and the hair layer comprises a second height that extends axially along the structure, where the first height is greater than the second height.

[0029] In some embodiments, the mesh layer extends closer to the exit end of the structure than the hair layer.

[0030] In another representative embodiment, a prosthetic heart valve comprises an annular structure comprising an inlet end and an outlet end and is radially compressible and expandable between a radially compressed configuration and a radially expanded configuration. The prosthetic heart valve further comprises a leaflet structure positioned within and attached to the structure, an external sealing element mounted outside the structure and adapted to seal against surrounding tissue when the prosthetic heart valve is implanted within a patient's native heart valve ring. The sealing element may comprise tissue with a variable thickness.

[0031] In some embodiments, the thickness of the fabric layer varies along a height and / or a circumference of the outer sealing element.

[0032] In some embodiments, the fabric comprises a plush fabric.

[0033] In some forms, the fabric comprises a plurality of hair strands and the height of the hair strands varies along a height and / or circumference of the outer skirt.

[0034] In some embodiments, the hair strands comprise a first group of strands along an upstream portion of the outer skirt and a second group of strands along a downstream portion of the outer skirt, wherein the strands of the first group have a height that is less than the height of the strands of the second group.

[0035] In some embodiments, the hair strands comprise a first group of strands along an upstream portion of the outer skirt and a second group of strands along a downstream portion of the outer skirt, wherein the strands of the first group have a height that is greater than the height of the strands of the second group.

[0036] In some embodiments, the hair strands comprise a first group of strands along an upstream portion of the outer skirt, a second group of strands along a downstream portion of the outer skirt, and a third group of strands Petition 870260077472, dated 04 / 08 / 2026, p. 17 / 91 7 / 42 between the first and second groups of wires, where the wires in the first and second groups have a height that is greater than the height of the wires in the third group.

[0037] In another representative embodiment, a prosthetic heart valve comprises an annular structure comprising an inlet end and an outlet end and is radially compressible and expandable between a radially compressed configuration and a radially expanded configuration. The prosthetic heart valve further comprises a leaflet structure positioned within and attached to the structure, an external sealing element mounted outside the structure and adapted to seal against surrounding tissue when the prosthetic heart valve is implanted within a patient's native heart valve ring. The sealing element may comprise a hair tissue comprising a plurality of hair strands, wherein the density of the hair strands varies in an axial and / or circumferential direction along the sealing element.

[0038] In some forms, the hair strands are arranged in rows of hair strands that extend circumferentially and the density of the hair strands varies from one row to another.

[0039] In some forms, the hair strands are arranged in rows of hair strands that extend axially and the density of the hair strands varies from one row to another.

[0040] In some embodiments, the sealing element comprises a mesh layer and a pile layer comprising pile yarns. In some embodiments, the weave density of the mesh layer varies in an axial and / or circumferential direction along the sealing element. In some embodiments, the mesh layer comprises one or more rows of higher density mesh parts and one or more rows of lower density mesh parts. One or more rows of higher density mesh parts and one or more rows of lower density mesh parts may be circumferentially extending rows and / or axially extending rows.

[0041] In another representative embodiment, a prosthetic heart valve comprises an annular structure comprising an inlet end and an outlet end and is radially compressible and expandable between a radially compressed configuration and a radially expanded configuration. A Petition 870260077472, dated 04 / 08 / 2026, p. 18 / 91 The 8 / 42 prosthetic heart valve further comprises a leaflet structure positioned within and attached to the structure, an external sealing element mounted outside the structure and adapted to seal against surrounding tissue when the prosthetic heart valve is implanted within a patient's native heart valve ring. The sealing element comprises a textile formed from a plurality of fibers arranged in a plurality of axially extending rows with higher stitch density, interspersed between a plurality of axially extending rows with lower stitch density. The sealing element is configured to stretch axially between a first, substantially relaxed, axially shortened configuration when the structure is in the radially expanded configuration and a second, axially elongated configuration when the structure is in the radially compressed configuration.

[0042] In some embodiments, each of the rows with the highest dot density can extend into a wavy pattern when the sealing element is in the axially shortened configuration. When the sealing element is in the axially lengthened configuration, the rows with the highest dot density move from the wavy pattern to the straight pattern.

[0043] In another representative embodiment, a prosthetic heart valve comprises an annular structure comprising an inlet end and an outlet end and is radially compressible and expandable between a radially compressed configuration and a radially expanded configuration. The prosthetic heart valve further comprises a leaflet structure positioned within and attached to the structure, an external sealing element mounted outside the structure and adapted to seal against surrounding tissue when the prosthetic heart valve is implanted within a patient's native heart valve ring. The sealing element comprises a tissue comprising a plurality of axially extending filaments and a plurality of circumferentially extending filaments.The sealing element is configured to stretch axially when the structure is radially compressed, moving from the radially expanded configuration to the radially compressed configuration. The axially extending filaments move from a deformed or twisted state when the structure is in the radially expanded configuration to a less deformed or less twisted state when the structure is in the radially compressed configuration. Petition 870260077472, dated 04 / 08 / 2026, page 19 / 91 9 / 42 radially compressed configuration.

[0044] In some embodiments, the axially extending filaments are heat-stabilized in the deformed or twisted state.

[0045] In some embodiments, the thickness of the sealing element decreases when the axially extending filaments move from the deformed or twisted state to the less deformed or twisted state. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a perspective view of a prosthetic heart valve, according to one embodiment.

[0047] Figure 2 is an enlarged perspective view of the inlet end portion of the prosthetic heart valve of Figure 1.

[0048] Figure 3 is a cross-sectional view of the prosthetic heart valve of Figure 1, showing the attachment of the outer skirt to the inner skirt and to the structure.

[0049] Figures 4-10 show an exemplary structure of the prosthetic heart valve of Figure 1.

[0050] Figures 11-12 show an exemplary inner skirt of the prosthetic heart valve of Figure 1.

[0051] Figures 13 - 15 show the inner skirt assembly of Figure 11 with the structure of Figure 4.

[0052] Figures 16 - 17 show the set of an exemplary leaflet structure.

[0053] Figure 18 shows the set of commissure parts of the leaflet structure with parts of the window frame of the structure.

[0054] Figures 19-20 show the leaflet structure assembly with the inner skirt along a lower edge of the leaflets.

[0055] Figures 21-23 are different views of an exemplary outer skirt of the prosthetic heart valve of Figure 1.

[0056] Figures 24-26 are seen in cross-section similar to Figure 3, but showing different modalities of the outer skirt.

[0057] Figures 27-28 show an alternative way of attaching an outer skirt to an inner skirt and / or to the structure of a prosthetic heart valve.

[0058] Figures 29-32 show another way of attaching an outer skirt to an inner skirt and / or to the structure of a prosthetic heart valve. Petition 870260077472, dated 04 / 08 / 2026, page 20 / 91 10 / 42

[0059] Figures 33-35 show another embodiment of an external sealing element for a prosthetic heart valve.

[0060] Figure 36 shows another embodiment of an external sealing element, shown mounted on the structure of a prosthetic heart valve.

[0061] Figure 37 is a flattened view of a woven mesh layer of the sealing element of Figure 36.

[0062] Figure 38 is a flattened view of a layer of hair from the sealing element of Figure 36.

[0063] Figure 39 is a flattened view of the external surface of an external sealing element for a prosthetic heart valve, according to another embodiment.

[0064] Figure 39A is an enlarged view of a part of the sealing element of Figure 39.

[0065] Figure 40 is a flattened view of the inner surface of the sealing element of Figure 39.

[0066] Figure 40A is an enlarged view of a part of the sealing element of Figure 40.

[0067] Figure 41 is a flattened view of an external sealing element for a prosthetic heart valve shown in a relaxed state when the prosthetic heart valve is radially expanded to its functional size, according to another embodiment.

[0068] Figure 42 is a flattened view of the outer sealing element of Figure 41 shown in a tensioned, axially elongated state when the prosthetic heart valve is in a radially compressed state for delivery.

[0069] Figure 43A is an enlarged view of a portion of another embodiment of an external sealing element for a prosthetic heart valve, in which the sealing element is shown in a relaxed state when the prosthetic heart valve is radially expanded to its functional size.

[0070] Figure 43B is an enlarged view of the sealing element of Figure 43A shown in a tensioned, axially elongated state when the prosthetic heart valve is in a radially compressed state for delivery.

[0071] Figure 44A is a cross-sectional view of the fabric of the sealing element of Figure 43A in a relaxed state. Petition 870260077472, dated 04 / 08 / 2026, page 21 / 91 11 / 42

[0072] Figure 44B is a cross-sectional view of the fabric of the sealing element of Figure 43B in a tensioned state. DETAILED DESCRIPTION

[0073] Figure 1 shows a prosthetic heart valve 10, according to one embodiment. The illustrated prosthetic valve is adapted for implantation in the native aortic annulus, although in other embodiments it may be adapted for implantation in the other native rings of the heart (e.g., the pulmonary, mitral, and tricuspid valves). The prosthetic valve may also be adapted for implantation in other tubular organs or passages in the body. The prosthetic valve 10 may have four main components: a stent or structure 12, a valve structure 14, an inner skirt 16, and a perivalvular outer sealing element or outer skirt 18. The prosthetic valve 10 may have an inlet end portion 15, an intermediate portion 17, and an outlet end portion 19.

[0074] The valve structure 14 may comprise three leaflets 40 (Figure 17), collectively forming a leaflet structure, which may be arranged to compress into a tricuspid arrangement. The lower edge of the leaflet structure 14 desirably has a wavy, curved, and scalloped shape (suture line 154 shown in Figure 20 follows the scalloped shape of the leaflet structure). By forming the leaflets with this scalloped geometry, the stresses on the leaflets are reduced, which in turn improves the durability of the prosthetic valve. Furthermore, by virtue of the scalloped shape, folds and undulations in the belly of each leaflet (the central region of each leaflet), which can cause premature calcification in these areas, can be eliminated or at least minimized. The scalloped geometry also reduces the amount of tissue material used to form the leaflet structure, thus allowing for a smaller and more uniform pleated profile at the inlet end of the prosthetic valve.The leaflets 40 may be formed from pericardial tissue (e.g., bovine pericardial tissue), biocompatible synthetic materials, or various other suitable natural or synthetic materials, as known in the art and described in U.S. Patent No. 6,730,118.

[0075] The bare structure 12 is shown in Figure 4. The structure 12 can be formed with a plurality of circumferentially spaced grooves or commissure windows 20 (three in the illustrated embodiment) that are adapted to mount the commissures of the valve structure 14 in the structure, as described in greater detail. Petition 870260077472, dated 04 / 08 / 2026, page 22 / 91 12 / 42 detail below. Structure 12 can be made of any of several suitable plastically expandable materials (e.g., stainless steel, etc.) or self-expanding materials (e.g., nickel-titanium alloy (NiTi), such as nitinol), as known in the art. When constructed of a plastically expandable material, structure 12 (and therefore the prosthetic valve 10) can be crimped to a radially compressed configuration in a delivery catheter and then expanded within a patient by an inflatable balloon or equivalent expansion mechanism. When constructed of a self-expanding material, structure 12 (and therefore the prosthetic valve 10) can be crimped to a radially compressed configuration and contained in the compressed configuration by insertion into a sheath or equivalent mechanism of a delivery catheter.Once inside the body, the prosthetic valve can be advanced from the delivery sheath, allowing the prosthetic valve to expand to its functional size.

[0076] Suitable plastically expandable materials that can be used to form structure 12 include, without limitation, stainless steel, biocompatible high-strength alloys (e.g., cobalt-chromium or nickel-cobalt-chromium alloys), polymers, or combinations thereof. In particular embodiments, structure 12 is made from a nickel-cobalt-chromium-molybdenum alloy, such as the MP35N® alloy (SPS Technologies, Jenkintown, Pennsylvania), which is equivalent to the UNS R30035 alloy (covered by ASTM F562-02). The MP35N® / UNS R30035 alloy comprises 35% nickel, 35% cobalt, 20% chromium, and 10% molybdenum, by weight. The use of the MP35N® alloy to form structure 12 has been found to provide superior structural results compared to stainless steel. In particular, when MP35N® alloy is used as the structural material, less material is needed to achieve the same, or better, performance in radial and crush strength, fatigue resistance, and corrosion resistance.Furthermore, since less material is required, the pleated profile of the structure can be reduced, thus providing a lower-profile prosthetic valve assembly for percutaneous delivery to the treatment site in the body.

[0077] Referring to Figures 4 and 5, structure 12 in the illustrated embodiment comprises a first lower row I of angled struts 22 arranged end to end and extending circumferentially at the entrance end of the structure; a second row II of angled struts extending Petition 870260077472, dated 04 / 08 / 2026, page 23 / 91 13 / 42 circumferentially 24; a third row III of circumferentially extending angled struts 26; a fourth row IV of circumferentially extending angled struts 28; and a fifth row V of circumferentially extending angled struts 32 at the structure's exit end. A plurality of substantially straight, axially extending struts 34 can be used to interconnect the struts 22 of the first row 1 with the struts 24 of the second row II. The fifth row V of angled struts 32 is connected to the fourth row IV of angled struts 28 by a plurality of axially extending window frame parts 30 (which define the commissure windows 20) and a plurality of axially extending struts 31.Each axial strut 31 and each part of the frame 30 extend from a location defined by the convergence of the lower ends of two angled struts 32 to another location defined by the convergence of the upper ends of two angled struts 28. Figures 6, 7, 8, 9 and 10 are enlarged views of the parts of the frame 12 identified by the letters A, B, C, D and E, respectively, in Figure 5.

[0078] Each commissure portion of the window frame 30 mounts a respective commissure of the leaflet structure 14. As can be seen, each portion of the frame 30 is fastened at the upper and lower ends to the adjacent rows of struts to provide a robust configuration that enhances the fatigue resistance under cyclic loading of the prosthetic valve compared to known cantilever struts for supporting the commissures of the leaflet structure. This configuration allows a reduction in the wall thickness of the frame to obtain a smaller pleated diameter of the prosthetic valve. In particular embodiments, the thickness T of the frame 12 (Figure 4) measured between the inner diameter and the outer diameter is about 0.48 mm or less.

[0079] The braces and frame parts collectively define a plurality of open frame cells. At the entry end of frame 12, braces 22, braces 24, and braces 34 define a lower row of cells defining openings 36. The second, third, and fourth rows of braces 24, 26, and 28 define two intermediate rows of cells defining openings 38. The fourth and fifth rows of braces 28 and 32, together with frame parts 30 and braces 31, define an upper row of cells defining openings 41. Openings 41 are relatively large and are sized to allow parts of the structure to Petition 870260077472, dated 04 / 08 / 2026, page 24 / 91 14 / 42 leaflet 14 project or protrude into and / or through the openings 41 when the frame 12 is gathered, in order to minimize the gathering profile.

[0080] As best shown in Figure 7, the lower end of strut 31 is connected to two struts 28 at a node or junction 44, and the upper end of strut 31 is connected to two struts 32 at a node or junction 46. Strand 31 may have a thickness SI less than the thicknesses S2 of junctions 44, 46. Junctions 44, 46, together with junctions 64, prevent complete closure of openings 41. The geometry of struts 31 and junctions 44, 46, and 64 helps create sufficient space in openings 41 in the compressed configuration to allow portions of the prosthetic leaflets to project or protrude outward through the openings. This allows the prosthetic valve to be crimped to a relatively smaller diameter than if all the leaflet material were confined within the crimped framework.

[0081] The frame 12 is configured to reduce, prevent, or minimize the possible overexpansion of the prosthetic valve at a predetermined balloon pressure, especially at the final outlet part of the frame, which supports the leaflet structure 14. In one aspect, the frame is configured to have relatively larger angles 42a, 42b, 42c, 42d, 42e between the struts, as shown in Figure 5. The larger the angle, the greater the force required to open (expand) the frame. As such, the angles between the frame struts can be selected to limit the radial expansion of the frame at a given opening pressure (e.g., balloon inflation pressure). In particular embodiments, these angles are at least 110 degrees or greater when the frame is expanded to its functional size, and more particularly, these angles are up to approximately 120 degrees when the frame is expanded to its functional size.

[0082] Furthermore, the entry and exit ends of a framework generally tend to expand more than the middle part of the framework due to the boning effect of the balloon used to expand the prosthetic valve. To protect against excessive expansion of the leaflet structure 14, the leaflet structure is desirably fixed to the framework 12 below the top row of braces 32, as best shown in Figure 1. Thus, in the event that the exit end of the framework is excessively expanded, the leaflet structure is positioned at a level below which excessive expansion is likely to occur, thereby protecting the Petition 870260077472, dated 04 / 08 / 2026, page 25 / 91 15 / 42 structure of the overexpansion leaflet.

[0083] In a known prosthetic valve construction, parts of the leaflets may project longitudinally beyond the frame outlet end when the prosthetic valve is shriveled IF the leaflets are mounted too close to the distal end of the frame. If the delivery catheter on which the shriveled prosthetic valve is mounted includes a push mechanism or stop element that pushes or stops against the prosthetic valve outlet end (e.g., to maintain the position of the shriveled prosthetic valve on the delivery catheter), the push element or stop element may damage the exposed leaflet portions that extend beyond the frame outlet end. Another benefit of mounting the leaflets at a location away from the frame outlet end is that when the prosthetic valve is shriveled onto a delivery catheter, the frame outlet end 12, rather than the leaflets 40, is the component closest to the prosthetic valve 10.Therefore, if the delivery catheter includes a push mechanism or stop element that pushes or rests against the outlet end of the prosthetic valve, the push mechanism or stop element contacts the outlet end of the frame, and not the leaflets 40, to avoid damage to the leaflets.

[0084] Furthermore, as can be seen in Figure 5, the openings 36 of the lowest row of openings in the frame are relatively larger than the openings 38 of the two intermediate rows of openings. This allows the frame, when pleated, to assume an overall conical shape that decreases from a maximum diameter at the exit end of the prosthetic valve to a minimum diameter at the inlet end of the prosthetic valve. When pleated, the frame 12 has a reduced diameter region that extends along a portion of the frame adjacent to the inlet end of the frame, which generally corresponds to the region of the frame covered by the outer skirt 18. In some embodiments, the reduced diameter region is reduced compared to the diameter of the upper part of the frame (which is not covered by the outer skirt), so that the outer skirt 18 does not increase the overall pleating profile of the prosthetic valve.When the prosthetic valve is implanted, the frame can expand to the generally cylindrical shape shown in Figure 4. In one example, the frame of a 26 mm prosthetic valve, when folded, has a first diameter of 14 French (unit of measurement). Petition 870260077472, dated 04 / 08 / 2026, page 26 / 91 16 / 42 (equivalent to 0.3 mm) at the outlet end of the prosthetic valve and a second diameter of 12 French at the inlet end of the prosthetic valve.

[0085] The main functions of the inner skirt 16 are to assist in fixing the valve structure 14 to the frame 12 and to assist in forming a good seal between the prosthetic valve and the native annulus, blocking blood flow through the open cells of the frame 12 below the lower edge of the leaflets. The inner skirt 16 preferably comprises a firm, tear-resistant material such as polyethylene terephthalate (PET), although various other synthetic materials or natural materials (e.g., pericardial tissue) may be used. The desirable thickness of the skirt is less than about 6 thousandths of an inch (about 0.15 mm) and desirably less than about 4 thousandths of an inch (about 0.1 mm) and even more desirably about 2 thousandths of an inch (about 0.05 mm). In particular variations, skirt size 16 may have varying thickness; for example, the skirt may be thicker at least on one of its edges than in its center.In one implementation, skirt 16 may comprise a PET skirt with a thickness of approximately 0.07 mm at its edges and about 0.06 mm at its center. The thinner skirt may provide better pleating performance while also providing good perivalve sealing.

[0086] The inner skirt 16 can be attached to the inside of the frame 12 by means of sutures 70, as shown in Figure 20. The valve structure 14 can be fixed to the skirt by means of one or more reinforcing strips 72 (which collectively can form a sleeve), for example, thin PET reinforcing strips, discussed below, which allow for secure suturing and protect the pericardial tissue of the leaflet structure from tearing. The valve structure 14 can be sandwiched between the skirt 16 and the thin PET strips 72, as shown in Figure 19. The sutures 154, which attach the PET strip and the leaflet structure 14 to the skirt 16, can be any suitable suture, such as Ethibond Excel® PEI suture (Johnson & Johnson, New Brunswick, New Jersey). The sutures 154 desirably follow the curvature of the lower border of the leaflet structure 14, as described in more detail below.

[0087] Known fabric skirts may comprise a fabric of warp and weft fibers extending perpendicularly to each other and with a set of fibers extending longitudinally between the upper and lower edges of the skirt. When the metal frame to which the fabric skirt is attached is Petition 870260077472, dated 04 / 08 / 2026, p. 27 / 91 17 / 42 radially compressed, the overall axial length of the frame increases. Unfortunately, a fabric skirt with limited elasticity cannot stretch along with the frame and therefore tends to deform the frame braces and prevent uniform gathering.

[0088] Referring to Figures 12, in contrast to known fabric skirts, skirt 16 is desirably woven from a first set of fibers, yarns or cords 78 and a second set of fibers, yarns or cords 80, both of which are not perpendicular to the upper edge 82 and the lower edge 84 of the skirt. In particular embodiments, the first set of fibers 78 and the second set of fibers 80 extend at angles of approximately 45 degrees (or 15-75 degrees or 30-60 degrees) relative to the upper and lower edges 82, 84. For example, skirt 16 can be formed by weaving the fibers at angles of 45 degrees relative to the upper and lower edges of the fabric. Alternatively, skirt 16 can be cut diagonally (cut on the bias) from a vertically woven fabric (where the fibers extend perpendicularly to the edges of the material), so that the fibers extend at 45-degree angles to the cut edges of the top and bottom skirt.As further shown in Figure 12, the opposite short edges 86, 88 of the skirt are desirably not perpendicular to the upper and lower edges 82, 84. For example, the short edges 86, 88 desirably extend at angles of approximately 45 degrees relative to the upper and lower edges and are therefore aligned with the first set of fibers 78. Therefore, the overall shape of the skirt is that of a rhomboid or parallelogram.

[0089] Figures 13 and 14 show the inner skirt 16 after the opposite short edge parts 90, 92 have been sewn together to set up the annular shape of the skirt. As shown, the edge part 90 can be placed in an overlapping relationship with respect to the opposite edge part 92 and the two edge parts can be sewn together with a row of stitches 94 that extends diagonally 94 which is parallel to the short edges 86, 88. The upper edge part of the inner skirt 16 can be formed with a plurality of projections 96 that define a wavy shape that generally follows the shape or contour of the fourth row of braces 28 immediately adjacent to the lower ends of the axial braces 31. In this way, as best shown in Figure 15, the upper edge of the inner skirt 16 can be firmly attached to the braces 28 with stitches 70. The inner skirt 16 also Petition 870260077472, dated 04 / 08 / 2026, p. 28 / 91 18 / 42 can be formed with slits 98 to facilitate the attachment of the skirt to the frame. The slits 98 are sized to allow a portion of the upper edge of the inner skirt 16 to be partially wrapped around the struts 28 and to reduce stress on the skirt during the attachment procedure. For example, in the illustrated embodiment, the inner skirt 16 is placed inside the frame 12 and a portion of the upper edge of the skirt is wrapped around the upper surfaces of the struts 28 and secured in place with sutures 70. Wrapping the portion of the upper edge of the inner skirt 16 around the struts 28 in this manner provides a stronger and more durable attachment of the skirt to the frame. The inner skirt 16 can also be attached to the first, second and / or third rows of struts 22, 24 and 26, respectively, with sutures 70.

[0090] Due to the angular orientation of the fibers relative to the upper and lower edges, the skirt can undergo greater elongation in the axial direction (i.e., in a direction from the upper edge 82 to the lower edge 84). Thus, when the metal frame 12 is gathered, the inner skirt 16 can elongate in the axial direction along with the frame and therefore provide a more uniform and predictable gathering profile. Each cell of the metal frame in the illustrated embodiment includes at least four angled struts that rotate in the axial direction during gathering (i.e., the angled struts become more aligned with the length of the frame). The angled struts of each cell function as a mechanism to rotate the fibers of the skirt in the same direction as the struts, allowing the skirt to extend along the length of the struts. This allows for greater elongation of the skirt and avoids undesirable deformations of the struts when the prosthetic valve is gathered.

[0091] In addition, the spacing between the fibers or yarns of the fabric can be increased to facilitate stretching of the skirt in the axial direction. For example, for a 16-pound PET inner skirt formed from 20-pound yarn, the yarn density can be approximately 15% to about 30% lower than in a typical PET skirt. In some examples, the yarn spacing of the 16-pound inner skirt can vary from approximately 60 yarns per cm (about 155 yarns per inch) to about 70 yarns per cm (approximately 180 yarns per inch), as well as approximately 63 yarns per cm (about 160 yarns per inch), while in a typical PET skirt the yarn spacing can vary from 85 yarns per cm (about 217 yarns per inch) to approximately 97 yarns per cm (about 247 yarns per inch). The Petition 870260077472, dated 04 / 08 / 2026, page 29 / 91 19 / 42 oblique edges 86, 88 promote a uniform and even distribution of fabric material along the inner circumference of the frame during gathering, so as to reduce or minimize fabric bunching to facilitate uniform gathering to the smallest possible diameter. Furthermore, cutting diagonal seams in a vertical manner can leave loose fringes along the cut edges. Oblique edges 86, 88 help to minimize this. Compared to the construction of a typical skirt (fibers running perpendicular to the upper and lower edges of the skirt), the inner skirt construction 16 avoids undesirable deformation of the frame supports and provides more uniform compression of the frame.

[0092] In alternative embodiments, the skirt may be formed from woven elastic fibers that can stretch in the axial direction during the gathering of the prosthetic valve. The warp and weft fibers may run perpendicular and parallel to the upper and lower edges of the skirt or, alternatively, may extend at angles between 0 and 90 degrees relative to the upper and lower edges of the skirt, as described above.

[0093] The inner skirt 16 can be sutured to the frame 12 at locations distant from the suture row 154, so that the skirt can be more flexible in that area. This configuration can avoid stress concentrations on the suture line 154, which attaches the lower edges of the leaflets to the inner skirt 16.

[0094] As noted above, the leaflet structure 14 in the illustrated embodiment includes three flexible leaflets 40 (although a greater or lesser number of leaflets may be used).

[0095] Additional information about the leaflets, as well as additional information about the skirt material, can be found, for example, in US Patent Application No. 14 / 704,861, filed on May 5, 2015.

[0096] Leaflets 40 can be fastened together on their adjacent sides to form commissures 122 of the leaflet structure (Figure 20). A plurality of flexible connectors 124 (one of which is shown in Figure 16) can be used to interconnect pairs of adjacent sides of the leaflets and to mount the leaflets onto the commissure parts of the window frame 30 (Figure 5). Figure 16 shows the adjacent sides of two leaflets 40 interconnected by a flexible connector 124. Three leaflets 40 can be fastened together side-by-side using three flexible connectors 124, as shown in Figure 17. Additional information on connecting the Petition 870260077472, dated 04 / 08 / 2026, page 30 / 91 The arrangement of 20 / 42 leaflets together, as well as the connection of the leaflets to the structure, can be found, for example, in US Patent Application Publication No. 2012 / 0123529.

[0097] As noted above, the inner skirt 16 can be used to assist in suturing the leaflet structure 14 to the frame. The inner skirt 16 may have a wavy temporary marking suture to guide the attachment of the lower edges of each leaflet 40. The inner skirt 16 itself can be sutured to the frame struts 12 using sutures 70, as noted above, before attaching the leaflet structure 14 to the skirt 16. The struts that cross the marking suture are desirably not attached to the inner skirt 16. This allows the inner skirt 16 to be more flexible in the areas not attached to the frame and minimizes stress concentrations along the suture line attaching the lower edges of the leaflets to the skirt. As noted above, when the skirt is attached to the frame, the 78, 80 fibers of the skirt (see Figure 12) generally align with the angled braces of the frame to promote uniform gathering and expansion of the frame.

[0098] Figure 18 shows a specific approach for attaching the corner parts 122 of the leaflet structure 14 to the corner parts of the window frame 30 of the frame. The flexible connector 124 (Figure 17) attaching two adjacent sides of two leaflets is folded in width and the upper parts of the flap 112 are folded down against the flexible connector. Each upper flap portion 112 is folded longitudinally (vertically) to assume an L-shape having an inner portion 142 folded against the inner surface of the leaflet and an outer portion 144 folded against the connector 124. The outer portion 144 can then be sutured to the connector 124 along a suture line 146. Next, the commissure flap assembly is inserted through the commissure window 20 of a corresponding window frame portion 30, and the folds outside the window frame portion 30 can be sutured to the portions 144.

[0099] Figure 18 also shows that the upper flap parts 112 folded down can form a double layer of leaflet material at the corners. The inner parts 142 of the upper flap parts 112 are positioned flat against the layers of the two leaflets 40 forming the corners, so that each corner comprises four layers of leaflet material just inside the window frames 30. This four-layer part of the corners can be Petition 870260077472, dated 04 / 08 / 2026, page 31 / 91 21 / 42 more resistant to bending or articulation than the leaflet portion 40 only radially inward from the relatively stiffer four-layer portion. This causes the leaflets 40 to articulate primarily at the inner edges 143 of the inner portions 142 bent downward in response to blood flowing through the prosthetic valve during operation within the body, rather than articulating around or near the axial struts of the window frames 30. Because the leaflets articulate at a location spaced radially inward from the window frames 30, the leaflets can avoid contact and damage from the frame. However, under high forces, the four-layer portion of the commissures can separate around a longitudinal axis adjacent to the window frame 30, with each inner portion 142 bent against its respective outer portion 144.For example, this can occur when the prosthetic valve 10 is compressed and mounted on a delivery shaft, allowing for a smaller crimp diameter. The four-layered commissure portion can also separate around the longitudinal axis when the balloon catheter is inflated during prosthetic valve expansion, which can relieve some of the pressure on the commissures caused by the balloon, reducing potential damage to the commissures during expansion.

[0100] After all three sets of corner tabs are attached to their respective parts of the window frame 30, the lower edges of the leaflets 40 between the sets of corner tabs can be sutured to the inner skirt 16. For example, as shown in Figure 19, each leaflet 40 can be sutured to the inner skirt 16 along suture line 154 using, for example, Ethibond Excel® PET suture. The sutures can be entry and exit sutures that extend through each leaflet 40, the inner skirt 16, and each reinforcement strip 72. Each leaflet 40 and its respective reinforcement strip 72 can be sewn separately to the inner skirt 16. In this way, the lower edges of the leaflets are attached to the frame 12 through the inner skirt 16.As shown in Figure 19, the leaflets can be further attached to the skirt with blanket sutures 156 that extend through each reinforcement strip 72, leaflet 40 and the inner skirt 16 while encircling the edges of the reinforcement strips 72 and leaflets 40. The blanket sutures 156 can be formed from PTFE suture material. Figure 20 shows a side view of the frame 12, leaflet structure 14 and the inner skirt 16 after attaching the leaflet structure 14 and the inner skirt 16 to the frame 12 and the leaflet structure 14 to the inner skirt 16. Petition 870260077472, dated 04 / 08 / 2026, p. 32 / 91 22 / 42

[0101] Figure 21 is a flattened view of the outer skirt 18 before its attachment to the frame 12, showing the outer surface of the skirt. Figure 22 is a flattened view of the outer skirt 18 before its attachment to the frame 12, showing the inner surface of the skirt. Figure 23 is a perspective view of the outer skirt before its attachment to the frame 12. The outer skirt 18 may be laser-cut or otherwise formed from a strong and durable material, such as PET or various other suitable synthetic or natural materials configured to restrict and / or impede blood flow through it. The outer skirt 18 may comprise a substantially straight lower edge portion 160 (inlet or upstream), an upper edge portion 162 (outlet or downstream) defining a plurality of alternating projections 164, and notches 166, or constellations, which generally follow the form of a row of frame struts.The lower and upper edge parts 160, 162 may have other shapes in alternative embodiments. For example, in one implementation, the lower edge part 160 may be formed with a plurality of projections generally conforming to the shape of a row of braces of the frame 12, while the upper edge part 162 may be straight.

[0102] In particular embodiments, the outer skirt 18 may comprise at least one soft surface, a radially outward oriented plush surface 168 so as to cushion and seal against native tissues around the prosthetic valve. In certain examples, the outer skirt 18 may be made from a variety of plain, knitted or crocheted fabrics, wherein the surface 168 is the surface of a plush pile or fur of the fabric. Examples of pile fabrics include velour, velvet, corduroy, terry cloth, fleece, etc. As best shown in FIG. 23, the outer skirt may have a base layer 170 (a first layer) from which a pile layer 172 (a second layer) extends. The base layer 170 may comprise warp and weft yarns woven or knitted in a mesh-like structure.For example, in a representative setup, the yarns for base layer 170 could be flat yarns and could have a weight range of approximately 7 dtex (decitex = yarn mass in grams for 10,000 m of yarn) to about 100 dtex, and could be knitted with a density of about 20 to about 100 stitches per inch and from approximately 30 to about 110 rows per inch. The yarns could be made of, for example, biocompatible thermoplastic polymers such as PET, PTFE. Petition 870260077472, dated 04 / 08 / 2026, p. 33 / 91 23 / 42 (polytetrafluoroethylene), nylon, etc., or any other suitable natural or synthetic fiber.

[0103] The pile layer 172 may comprise pile yarns 174 woven or knitted into loops. In certain configurations, pile yarns 174 may be the warp yarns or weft yarns of the base layer 170 woven or knitted to form the loops. Pile yarns 174 may also be separate yarns incorporated into the base layer, depending on the particular characteristics desired. In a representative configuration, pile yarns 174 may be flat yarns and may have a weight range from approximately 7 dtex (decitex = yarn mass in grams for 10,000 m of yarn) to about 100 dtex, and may be knitted with a density of about 20 to about 100 columns per inch and from approximately 30 to about 110 rows per inch. The yarn can be made from, for example, biocompatible thermoplastic polymers such as PET, PTFE, nylon, etc., or any other suitable natural or synthetic fibers.

[0104] In certain embodiments, the loops may be cut so that the pile layer 172 is a pile cut in the manner of, for example, a velour fabric. Figures 1 and 21 illustrate a representative embodiment of the outer skirt 18 configured as a velour fabric. In other embodiments, the loops may be left intact to form a looped pile in the manner of, for example, terrycloth. Figure 23 illustrates a representative embodiment of the outer skirt 18 in which the pile strands 174 are knitted to form loops 176.

[0105] The height of the hair strands 174 (e.g., loops 176) may be the same for all hair strands throughout the length of the outer skirt, so as to provide an outer skirt that has a constant thickness. In alternative embodiments, the height of the hair strands 174 may vary along the height and / or circumference of the outer skirt, so as to vary the thickness of the outer skirt along its height and / or circumference, as described below.

[0106] The hair layer 172 has a much larger surface area than similarly sized skirts formed from flat materials or tissue and therefore can increase tissue growth compared to known skirts. Promoting tissue growth in the hair layer 172 may decrease perivalvular leakage, increase valve retention at the implant site, and contribute to long-term valve stability. In some configurations, Petition 870260077472, dated 04 / 08 / 2026, p. 34 / 91 24 / 42 The surface area of ​​hair strands 174 can be further increased by using textured strands with an increased surface area due to, for example, a wavy structure. In configurations such as the looped hair modality of Figure 23, the loop structure and increased surface area provided by the textured yarn of the loops 176 can allow the loops to act as a scaffold for tissue growth within and around the hair loops.

[0107] The outer skirt embodiments described in this document may also contribute to improving the compressibility and shape memory properties of the outer skirt over known valve linings and skirts. For example, the 172 hair layer may be compliant so that it compresses under load (e.g., when in contact with tissue, other implants, or the like) and returns to its original size and shape when the load is relieved. This may help improve the seal between the outer skirt and the native annulus tissue or a surrounding support frame in which the prosthetic valve is implanted. Embodiments of an implantable support frame that is adapted to receive a prosthetic valve and retain it within the native mitral valve are described in co-pending application No. 62 / 449,320, filed on January 23, 2017, and application No. 15 / 876,053, filed on January 19, 2018.The compressibility provided by the 172 layer of the outer skirt 18 is also beneficial in reducing the valve's puckering profile. Furthermore, the outer skirt 18 can prevent the leaflets 40 or parts thereof from extending through gaps between the frame struts 12 when the prosthetic valve is puckered, thus protecting against damage to the leaflets due to compression between the struts.

[0108] In alternative embodiments, the outer skirt 18 is made of a nonwoven fabric, such as felt, or fibers, such as nonwoven cotton fibers. The outer skirt 18 may also be made of porous or spongy materials, such as, for example, any of a variety of compatible polymer foam materials or fabrics, such as PET fabric.

[0109] Various techniques and configurations can be used to attach the outer skirt 18 to the frame 12 and / or to the inner skirt 16. As best shown in Figure 3, a portion of the lower edge 180 of the inner skirt 16 can be wrapped around the entry end 15 of the frame 12, and a portion of the lower edge 160 of the outer skirt 18 can be attached to a portion of the lower edge 180 of the inner skirt 16 and / or to Petition 870260077472, dated 04 / 08 / 2026, p. 35 / 91 25 / 42 frame 12, as with one or more sutures or stitches 182 (as best shown in Figure 2) and / or an adhesive. Instead of or in addition to sutures, the outer skirt 18 may be attached to the inner skirt 16, for example, by ultrasonic welding. In the illustrated embodiment, the lower edge 160 of the outer skirt 18 may be free of loops, and the lower edge 180 of the inner skirt 16 may overlap and be attached to the base layer 170 of the outer skirt 18. In other embodiments, the lower edge 180 of the inner skirt 16 may extend over one or more rows of loops 176 of the hair layer 172 (see Figure 27), as described below. In other embodiments, the lower edge portion 180 of the inner skirt 18 may be wrapped around the entry end of the frame and extend between the outer surface of the frame and the outer skirt 18 (i.e., the outer skirt 18 is radially outward from the lower edge portion 180 of the inner skirt 18).

[0110] As shown in Figure 1, each projection 164 of the outer skirt 18 can be attached to the third row III of the braces 26 (Figure 5) of the frame 12. The projections 164 can, for example, be wrapped around the respective braces 26 of row III and fastened with sutures 184. The outer skirt 18 can also be fixed to the frame 12 by suturing an intermediate part of the outer skirt (a part between the lower and upper edge parts) to the braces of the frame, just as the supports 24 of the second row II of braces are attached to the braces of the frame, just as the braces 24 of the second row II of braces are attached to the braces of the frame.

[0111] The height of the outer skirt (as measured from the bottom edge to the top edge) may vary in alternative embodiments. For example, in some embodiments, the outer skirt may cover the entire outer surface of the frame 12, with the bottom edge portion 160 attached to the entry end of the frame 12 and the top edge portion attached to the exit end of the frame. In another embodiment, the outer skirt 18 may extend from the entry end of the frame to the second row II of the braces 24, or to the fourth row IV of the braces 28, or to a location along the frame between two rows of braces. Still in other embodiments, the outer skirt 18 need not extend to the entry end of the frame and, instead, the entry end of the outer skirt may be attached to another location on the frame, such as the second row II of braces 24.

[0112] The outer skirt 18 is desirably dimensioned and shaped in relation to the frame, so that when the prosthetic valve 10 is in its state Petition 870260077472, dated 04 / 08 / 2026, page 36 / 91 26 / 42 radially expanded, the outer skirt 18 fits snugly (in a well-fitting manner) against the outer surface of the frame. When the prosthetic valve 10 is radially compressed to a compressed state for delivery, the part of the frame on which the outer skirt is mounted can elongate axially. The outer skirt 18 desirably has sufficient elasticity to stretch in the axial direction after radial compression of the frame, so that it does not impede full radial compression of the frame or deform the struts during the ruffling process.

[0113] It is difficult to assemble known skirts that exhibit slack or folding of the material when the prosthetic valve is expanded to its functional size, because the material must be adjusted as it is sutured to the framework. On the other hand, because the outer skirt 18 is sized to fit comfortably around the framework in its fully expanded state, the assembly process of attaching the skirt to the framework is greatly simplified. During the assembly process, the outer skirt can be placed around the framework with the framework in its fully expanded state and the outer skirt in its final shape and position when the valve is fully functional. In this position, the skirt can then be sutured to the framework and / or the inner skirt. This simplifies the suturing process compared to skirts that are designed to have slack or folds when expanded radially.

[0114] As shown in Figure 3, the height of the loops of the fur layer 172 may be constant throughout the length of the outer skirt, so that the outer skirt 18 has a constant thickness, except along the upper and lower edge parts which may be free of loops to facilitate attachment of the outer skirt to the frame and / or inner skirt 16. The height of the loops is measured in the radial direction when the skirt is mounted on the frame. In another embodiment, as shown in Figure 24, the loops may comprise the lower loops 176a along the bottom or upstream of the skirt which are relatively lower in height (as represented by a thinner cross-sectional area) than the upper loops 176b (as represented by a thicker cross-sectional area) along the top or downstream of the skirt.The skirt 18 may also include a group of intermediate loops 176c that gradually increase in height from the lower loops 176a to the upper loops 176b. Thus, in the embodiment of Figure 24, the thickness of the outer skirt 18 increases by a minimum thickness along the part. Petition 870260077472, dated 04 / 08 / 2026, p. 37 / 91 27 / 42 lower for maximum thickness along the top.

[0115] Figure 25 shows another embodiment in which the outer skirt loops comprise lower loops 176d along the bottom of the skirt that are relatively larger or longer in height than the upper loops 176e along the top of the skirt. The skirt 18 may further include a group of intermediate loops 176f that gradually decrease in height from the lower loops 176d to the upper loops 176e. Thus, in the embodiment of Figure 25, the thickness of the outer skirt 18 decreases from a maximum thickness along the bottom to a minimum thickness along the top.

[0116] Figure 26 shows another embodiment in which the loops comprise lower loops 176g, upper loops 176h, and intermediate loops 176i that are relatively smaller in height than the lower and upper loops. As shown, the lower loops 176g can gradually decrease in height from the lower edge of the skirt towards the intermediate loops 176i, and the upper loops 176h can gradually decrease in height from the upper edge of the skirt towards the intermediate loops 176i. Thus, in the embodiment of Figure 26, the thickness of the outer skirt decreases from a maximum thickness along the bottom to a minimum thickness along the middle and then increases from the middle to the maximum thickness along the top. In the illustrated embodiment, the upper part of the skirt containing the upper loops 176h has the same thickness as the lower part of the skirt containing the lower loops 176g.In other versions, the thickness of the upper part of the skirt containing the upper ties 176h may be greater or less than the same thickness of the lower part of the skirt containing the lower ties 176g.

[0117] Furthermore, in any of the embodiments described above, where the height of the loops varies along the height of the skirt, the height of the loops need not vary gradually from one section of the skirt to another section of the skirt. Thus, an outer skirt may have loops of different heights, where the height of the loops changes abruptly at locations along the skirt. For example, in the embodiment of Figure 24, the lower part of the skirt containing the lower loops 176a may extend all the way to the upper part of the skirt containing the upper loops 176g without the intermediate loops 176c forming a transition between the upper and lower parts. Petition 870260077472, dated 04 / 08 / 2026, p. 38 / 91 28 / 42

[0118] Instead of or in addition to having loops that vary in height along the height of the skirt, the height of the loops 176 (and therefore the thickness of the outer skirt) may vary along the circumference of the outer skirt. For example, the height of the loops may be increased along circumferential sections of the skirt where larger spaces between the outer skirt and the native ring may be expected, such as circumferential sections of the skirt that are aligned with the commissures of the native valve.

[0119] Figures 27 and 28 show an alternative configuration for mounting the outer skirt 18 on the frame 12. In this embodiment, as best shown in Figure 27, the lower edge portion 180 of the inner skirt 16 is wrapped around the entry end of the frame and extended by one or more rows of loops along the lower edge portion 160 of the outer skirt. The lower edge portion 180 of the inner skirt 16 can then be attached to the lower edge portion 160 of the outer skirt, as with sutures or stitching 186 (Figure 28), an adhesive and / or welding (e.g., ultrasonic welding). The stitching 186 can also extend around selected struts adjacent to the entry end of the frame. The lower edge portion 180 of the inner skirt is effective in partially compressing the hair layer loops 172, which creates a thinned edge at the entry end of the prosthetic valve.The thinned edge reduces the insertion force required to push the prosthetic valve through an introducer sheath when inserted into a patient's body. In a specific implementation, the seam 186 attaches the lower edge portion 180 of the inner skirt to the outer skirt 18 at a distance of at least 1 mm from the lower edge of the outer skirt. The upper edge portion 162 and the middle portion of the outer skirt can then be attached to the frame as described previously.

[0120] Figures 29-32 show another configuration for mounting the outer skirt 18 on the frame 12. In this embodiment, the outer skirt 18 is initially placed in a tubular configuration with the base layer 170 facing outwards and the lower edge portion 160 (which may be free of ties 176) may be placed between the inner surface of the frame 12 and the lower edge portion 180 of the inner skirt 16, as shown in Figure 30. The lower edge portions of the outer skirt and the inner skirt may be fastened to each other, such as with stitches, an adhesive and / or welding (e.g., ultrasonic welding). In one implementation, the lower edge portions of the outer skirt and the inner skirt are fastened to each other with stitches. Petition 870260077472, dated 04 / 08 / 2026, page 39 / 91 29 / 42 entry and exit points and locking points. The outer skirt 18 is then inverted and pulled upwards around the outer surface of the frame 12, so that the base layer 170 is placed against the outer surface of the frame and the fur layer 172 faces outwards, as shown in Figure 29. In this assembled configuration, the lower edge portion 160 of the outer skirt wraps around the entry end of the frame and is attached to the inner skirt inside the frame. The upper edge portion 162 and the middle portion of the outer skirt can then be attached to the frame as described previously.

[0121] The prosthetic valve 10 can be configured and mounted on a suitable delivery device for implantation in a patient. Several catheter-based delivery devices are known; a non-limiting example of a suitable catheter-based delivery device includes that described in U.S. Patent Application Publication No. 2013 / 0030519 and U.S. Patent Application Publication No. 2012 / 0123529.

[0122] To implant a plastically expandable prosthetic valve 10 within a patient, the prosthetic valve 10 including the outer skirt 18 can be pleated over an elongated shaft of a delivery device. The prosthetic valve, together with the delivery device, can form a delivery assembly to implant the prosthetic valve 10 into a patient's body. The shaft may comprise an inflatable balloon to expand the prosthetic valve within the body. With the balloon deflated, the prosthetic valve 10 can then be delivered percutaneously to a desired implantation site (e.g., a native aortic valve region). Once the prosthetic valve 10 is delivered to the implantation site (e.g., the native aortic valve) within the body, the prosthetic valve 10 can be radially expanded to its functional state by inflating the balloon or equivalent expansion mechanism.

[0123] The outer skirt 18 can fill gaps between the frame 12 and the surrounding native ring to help form a good fluid-tight seal between the prosthetic valve 10 and the native ring. The outer skirt 18 therefore cooperates with the inner skirt 16 to prevent perivalvular leakage after implantation of the prosthetic valve 10. Furthermore, as discussed above, the hair layer of the outer skirt further enhances the perivalvular seal by promoting tissue growth with the surrounding tissue.

[0124] Alternatively, a self-expanding prosthetic valve 10 may be Petition 870260077472, dated 04 / 08 / 2026, page 40 / 91 30 / 42 pleated into a radially collapsed configuration and contained within the collapsed configuration by inserting the prosthetic valve 10, including the outer skirt 18, into a sheath or equivalent mechanism of a delivery catheter. The prosthetic valve 10 can then be delivered percutaneously to a desired implantation site. Once inside the body, the prosthetic valve 10 can be advanced from the delivery sheath, allowing the prosthetic valve to expand to its functional state.

[0125] Figure 33 illustrates a sealing element 200 for a prosthetic valve, according to another embodiment. The sealing element 200 in the illustrated embodiment is formed from a spacer fabric. The sealing element 200 can be positioned around the outer surface of the frame 12 of a prosthetic valve (in place of the outer skirt 18) and attached to the inner skirt 16 and / or to the frame using stitching, adhesive and / or welding (e.g., ultrasonic welding).

[0126] As best shown in Figure 34, the spacer fabric may comprise a first inner layer 206, a second outer layer 208, and an intermediate spacer layer 210 extending between the first and second layers to create a three-dimensional fabric. The first and second layers 206, 208 may be woven or mesh layers. In certain configurations, one or more of the first and second layers 206, 208 may be woven so as to define a plurality of openings 212. In some examples, openings such as the openings 212 may promote fabric growth in the sealing element 200. In other embodiments, the layers 206, 208 need not define openings but may be porous as desired.

[0127] The spacer layer 210 may comprise a plurality of hair strands 214. The hair strands 214 may be, for example, monofilament strands arranged to form a scaffold-like framework between the first and second layers 206, 208. For example, Figures 34 and 35 illustrate an embodiment in which the hair strands 214 extend between the first and second layers 206, 208 in a sinusoidal or loop pattern.

[0128] In certain examples, the hair strands 214 may have a higher stiffness than the stiffness of the tissue of the first and second layers 206, 208, so that the hair strands 214 may extend between the first and second layers 206, 208 Petition 870260077472, dated 04 / 08 / 2026, p. 41 / 91 31 / 42 without collapsing under the weight of the second layer 208. The hair strands 214 may also be sufficiently resilient, such that the hair strands can bend or yield when subjected to a load, allowing the tissue to compress and return to its undeflected state when the load is removed. For example, when the prosthetic valve is radially compressed for delivery into the patient's body and placed in a delivery sheath of a delivery device or advanced through an introducer sheath, the hair strands 214 may compress to reduce the overall puckering profile of the prosthetic valve and then return to their undeflected state when implanted from the delivery sheath or introducer sheath, as the case may be.

[0129] The spacer fabric can be knitted in warp or weft, as desired. Some configurations of the spacer fabric can be made on a double-bar knitting machine. In a representative example, the first and second layer yarns 206, 208 can have a weight range of about 10 dtex to about 70 dtex (dtex = decitex = yarn mass in grams for 10,000 m of yarn), and the yarns of the monofilament pile yarn 214 can have a weight range of approximately 2 mil to about 10 mil. The pile yarn 214 can have a knitting density of approximately 20 to about 100 columns per inch and approximately 30 to about 110 rows per inch. Furthermore, in some configurations (e.g., warp spacer fabrics), materials with different flexibility properties can be incorporated into the spacer fabric to improve the overall flexibility of the spacer fabric.

[0130] Figure 36 shows an external sealing element 18' mounted on the outside of the frame 12 of a prosthetic heart valve 10, according to another embodiment. Figure 37 shows the base layer 170 of the sealing element 18' in a flattened configuration. Figure 38 shows the base layer 172 of the sealing element 18' in a flattened configuration. The external sealing element 18' is similar to the sealing element 18 of Figures 1 and 21-23, except that the height (H1) of the base layer 170 is greater than the height (H2) of the base layer 172. As described in the embodiments above, the sealing element 18 is desirably dimensioned and shaped relative to the frame 12, so that when the prosthetic valve is in its radially expanded state, both layers 170, 172 of the sealing element 18 fit together. Petition 870260077472, dated 04 / 08 / 2026, page 42 / 91 32 / 42 fits comfortably (in a well-fitting manner) around the outer surface of the frame.

[0131] In the illustrated configuration, base layer 170 extends axially from the entry end of frame 12 to the third row III of struts 26 of frame 12. The upstream and downstream edges of base layer 170 can be sutured to struts 22 of first row I and struts 26 of third row III with sutures 182 and 184, respectively, as described previously. The fur layer 172 in the illustrated configuration extends from the entry end of frame 12 to a plane that crosses the frame at the nodes formed at the intersection of the upper ends of struts 24 of second row II and the lower ends of struts 26 of third row III, where the plane is perpendicular to the central axis of the frame.

[0132] The brace layer 172 can be formed separately and subsequently attached to the base layer 170, such as by sutures, an adhesive, and / or welding. Alternatively, the hair layer 172 can be formed from yarns or fibers woven into the base layer 170. The hair layer 172 can have any of the configurations shown in Figures 24-26.

[0133] In particular embodiments, the height Hi of the base layer 170 may be from approximately 9 mm to about 25 mm or approximately 13 mm to about 20 mm, with approximately 19 mm being a specific example. The height Ha of the hair layer 172 may be at least 2 mm less than Hi, at least 3 mm less than Hi, at least 4 mm less than Hi, at least 5 mm less than Hi, at least 6 mm less than Hi, at least 7 mm less than Hi, at least 8 mm less than Hi, at least 9 mm than Hi, or at least 10 mm less than Hi. The height of the frame 12 in the radially expanded state may be approximately 12 mm to about 27 mm or approximately 15 mm to about 23 mm, with approximately 20 mm being a specific example.

[0134] The relatively shorter hair layer 172 reduces the puckering profile along the intermediate section of the prosthetic valve 10, but still provides improved paravalvular sealing along most of the prosthetic valve landing zone. The base layer 170 also provides a downstream sealing function of the downstream edge of the hair layer 172.

[0135] Figures 39-40 show an external sealing element 300 for Petition 870260077472, dated 04 / 08 / 2026, page 43 / 91 33 / 42 a prosthetic heart valve (e.g., a prosthetic heart valve 10) according to another embodiment. Figures 39A and 40A are enlarged views of parts of the sealing element shown in Figures 39 and 40 respectively. The sealing element 300 can be mounted on the outside of the frame 12 of a prosthetic valve 10 instead of the sealing element 18, using, for example, sutures, ultrasonic welding or any other suitable fixation method. As described previously in the embodiments, the sealing element 300 is desirably dimensioned and shaped relative to the frame 12, so that when the prosthetic valve is in its radially expanded state, the sealing element 300 fits snugly (in a well-fitting manner) against the outer surface of the frame.

[0136] The sealing element 300, like the sealing elements 18, 18', may be a double-layer fabric comprising a base layer 302 and a pile layer 304. Figure 39 shows the outer surface of the sealing element 300 defined by the pile layer 304. Figure 40 shows the outer surface of the sealing element 300 defined by the pile layer 302. The base layer 302 in the illustrated configuration comprises a mesh weave with rows or bands 306 extending circumferentially from denser mesh portions interspersed with rows or bands 308 of less dense mesh portions.

[0137] In particular embodiments, the wire count of wires extending in the circumferential direction (side by side or horizontally in Figures 40 and 40A) is higher in the higher density rows 306 than in the lower density rows 308. In other embodiments, the wire count of wires extending in the circumferential direction and the wire count of wires extending in the axial direction (vertically in Figures 40 and 40A) is higher in the higher density rows 306 than in the lower density rows 308.

[0138] The pile layer 304 may be formed from yarns woven into the base layer 302. For example, the pile layer 304 may comprise a velvet fabric formed from yarns incorporated into the base layer 302. The pile layer 304 may comprise circumferentially extending rows or bands 310 of pile formed at axially spaced locations along the height of the sealing element 300, so that there are extended axial spaces. Petition 870260077472, dated 04 / 08 / 2026, page 44 / 91 34 / 42 between adjacent rows 310. In this way, the density of the hair layer varies along the height of the sealing element. In alternative embodiments, the hair layer 304 may be formed without gaps between adjacent rows of hair, but the hair layer may comprise rows or strips extending circumferentially of denser hair interspersed with rows or strips 312 of less dense hair.

[0139] In alternative embodiments, the base layer 302 may comprise a uniform mesh fabric (the density of the fabric pattern is uniform) and the pile layer 304 has a variable density.

[0140] Varying the density of the hair layer 304 and / or the base layer 302 along the height of the sealing element 300 is advantageous, as it facilitates the axial elongation of the sealing element 300 caused by the axial elongation of the frame 12 when the prosthetic heart valve is crimped to a radially compressed state for delivery. The variable density also reduces the volume of the sealing element in the radially compressed state and therefore reduces the overall crimping profile of the prosthetic heart valve.

[0141] In alternative embodiments, the density of the sealing element 300 may vary along the circumference of the sealing element to reduce the volume of the sealing element in the radially compressed state. For example, the hair layer 304 may comprise a plurality of axially extending, circumferentially spaced rows of hair strands, or alternatively, alternating axially extending rows of higher density hair interspersed with axially extending rows of lower density hair. Similarly, the base layer 302 may comprise a plurality of axially extending rows of higher density mesh interspersed with rows of lower density mesh.

[0142] In other embodiments, the sealing element 300 may include a base layer 302 and / or a hair layer 304 that varies in density along the circumference of the sealing element and along the height of the sealing element.

[0143] In other embodiments, a sealing element may be knitted, crocheted, or woven to have rows or sections of higher stitch density and rows or sections of lower stitch density without two distinct layers. Figure 41, for example, shows a sealing element 400 comprising a fabric with Petition 870260077472, dated 04 / 08 / 2026, page 45 / 91 35 / 42 a plurality of axially extending rows 402 of higher stitch density alternating with axially extending rows 404 of lower stitch density. The sealing element 400 can be formed, for example, by knitting, crocheting or weaving a single-layer fabric with the formed rows 402, 404, increasing the stitch density along rows 402 and decreasing the stitch density along rows 404 as the fabric is formed. The sealing element 400 can be mounted on the outside of the frame 12 of a prosthetic valve 10 instead of the sealing element 18, using, for example, sutures, ultrasonic welding or any other suitable fixation method.As previously described in the embodiments, the sealing element 400 is desirably dimensioned and shaped in relation to the frame 12, so that when the prosthetic valve is in its radially expanded state, the sealing element 400 fits snugly (in a well-fitting manner) against the outer surface of the frame.

[0144] The sealing element 400 can be resiliently elastic between a first substantially relaxed and axially shortened configuration (Figure 41) corresponding to a radially expanded state of the prosthetic valve and a second axially elongated or tensioned configuration (Figure 42) corresponding to a radially compressed state of the prosthetic valve. As shown in Figure 41, when the prosthetic valve is radially expanded and the sealing element 400 is in the first configuration, the higher density rows 402 extend in a wavy pattern from the bottom (upstream edge) to the top (downstream edge) of the sealing element 400.In the illustrated embodiment, for example, each of the higher density rows 402 comprises a plurality of right-angled sections 406a, 406b arranged end-to-end in a zigzag or herringbone pattern extending from the bottom (upstream edge) to the top (downstream edge) of the sealing element 400. In alternative embodiments, the rows 402 may be sinusoidal rows with curved longitudinal edges.

[0145] When the prosthetic valve is crimped to its radially compressed state, the frame 12 elongates, causing the sealing element to stretch in the axial direction, as shown in Figure 42, to its second configuration. The lower density rows 404 facilitate the elongation of the element. Petition 870260077472, dated 04 / 08 / 2026, page 46 / 91 36 / 42 sealing and allow straightening of the higher density rows 402. Figure 42 represents the higher density rows 402 as straight sections extending from the inlet edge to the outlet edge of the sealing element. However, it should be understood that the higher density rows 402 do not need to form perfectly straight rows when the prosthetic valve is in the radially compressed state. Instead, straightening of the higher density rows 402 occurs when the angle 408 between the adjacent angular segments 406a, 406b of each row increases with the axial elongation of the sealing element.

[0146] The variable density of the sealing element 400 points reduces the overall volume of the sealing element to minimize the puckering profile of the prosthetic valve. The zigzag or wavy pattern of the high-density rows 402 in the radially expanded state of the prosthetic valve facilitates the elongation of the sealing element in the axial direction by radial compression of the prosthetic valve and allows the sealing element to return to its pre-stretched state, in which the sealing element fits tightly around the frame by radial expansion of the prosthetic valve. Furthermore, the zigzag or wavy pattern of the higher-density rows 402 in the radially expanded state of the prosthetic valve eliminates any straight flow paths for blood between adjacent rows 402 extending along the outer surface of the sealing element from the exit edge to its entry edge to facilitate sealing and tissue growth with the surrounding tissue.

[0147] In alternative embodiments, a 400 sealing element may have a plurality of high-density rows that extend circumferentially (like 402 rows, but extending in the circumferential direction). In some embodiments, a 400 sealing element may have high-density rows that extend axially and with circumferential extension interspersed with lower-density rows that extend axially and with circumferential extension.

[0148] Figures 43A, 43B, 44A, and 44B illustrate an external sealing element 500 for a prosthetic heart valve (e.g., a prosthetic heart valve 10) according to another embodiment. The sealing element 500 may have a plush outer surface 504. The sealing element 500 may be fixed to a frame 12 of the prosthetic valve using, for example, sutures, ultrasonic welding, or any other suitable fixation method, as described. Petition 870260077472, dated 04 / 08 / 2026, page 47 / 91 37 / 42 previously in this document. For illustrative purposes, enlarged or augmented portions of the sealing element 500 are shown in the figures. It should be understood that the overall size and shape of the sealing element 500 may be modified as necessary to cover the entire outer surface of the frame 12 or part of the outer surface of the frame, as described previously in this document.

[0149] The sealing element 500 may comprise a fabric or mesh. The fabric may be resiliently elastic between a first, natural or relaxed configuration (Figures 43A) and a second, axially elongated or tensioned configuration (Figures 43B). When arranged in the frame 12, the relaxed configuration may correspond to the radially expanded functional configuration of the prosthetic valve, and the elongated configuration may correspond to the radially compressed delivery configuration of the prosthetic valve. Thus, with reference to Figure 43A, the sealing element 500 may have a first length L1 in the axial direction when the prosthetic valve is in the radially expanded configuration and a second length L2 (Figure 43B) in the axial direction that is greater than L1 when the valve is compressed in the delivery configuration, as described in more detail below.

[0150] The fabric may comprise a plurality of warp yarns of circumferential length 512 and a plurality of weft yarns of axial length 514. In some embodiments, the warp yarns 512 may have a yarn density (denier) of approximately 1 D to approximately 300 D, approximately 10 D to approximately 200 D, or approximately 10 D to approximately 100 D. In some embodiments, the warp yarns 512 may have a thickness t1 (Figure 44A) of approximately 0.01 mm to approximately 0.5 mm, approximately 0.02 mm to approximately 0.3 mm, or approximately 0.03 mm to approximately 0.1 mm. In some embodiments, the 512 warp yarns may have a thickness t1 of approximately 0.03 mm, approximately 0.04 mm, approximately 0.05 mm, approximately 0.06 mm, approximately 0.07 mm, approximately 0.08 mm, approximately 0.09 mm, or approximately 0.1 mm.In a representative embodiment, the 512 warp yarns may have a thickness of approximately 0.06 mm.

[0151] Weft yarns 514 may be textured yarns comprising a plurality of textured filaments 516. For example, the filaments 516 of the yarns Petition 870260077472, dated 04 / 08 / 2026, page 48 / 91 38 / 42 weft 514 yarns can be augmented, whereby, for example, 516 filaments are twisted, heated, and untwisted, so that the filaments retain their deformed and twisted shape in the relaxed, unstretched configuration. 516 filaments can also be textured by puckering, winding, etc. When 514 weft yarns are in a relaxed, tension-free state, 516 filaments can be loosely packed and can provide bulk or compressible volume to the fabric, as well as a plush surface. In some embodiments, 514 weft yarns may have a yarn density (denier) of approximately 1 D to approximately 500 D, approximately 10 D to approximately 400 D, approximately 20 D to approximately 350 D, approximately 20 D to approximately 300 D, or approximately 40 D to approximately 200 D. In certain embodiments, 514 weft yarns may have a yarn density of approximately 150 D.In some embodiments, a filament count of the 514 weft yarns may be from 2 filaments per yarn to 200 filaments per yarn, 10 filaments per yarn to 100 filaments per yarn, 20 filaments per yarn to 80 filaments per yarn, or approximately 30 filaments per yarn to 60 filaments per yarn. Furthermore, although the axial extension textured yarns 514 are referred to as weft yarns in the illustrated configuration, the fabric may also be manufactured so that the axial extension textured yarns are warp yarns and the circumferential extension yarns are weft yarns.

[0152] Figures 44A and 44B illustrate a cross-sectional view of the sealing element in which the weft yarns 512 extend to the page plane. With reference to Figure 44A, the fabric of the sealing element 500 may have a thickness t2 of approximately 0.1 mm approximately 10 mm, approximately 1 mm approximately 8 mm, approximately 1 mm approximately 5 mm, approximately 1 mm approximately 3 mm, approximately 0.5 mm, approximately 1 mm, approximately 1.5 mm, approximately 2 mm, approximately 2.5 mm or approximately 3 mm when in a relaxed state and attached to a frame. In some embodiments, the sealing element 500 may have a thickness of approximately 0.1 mm, approximately 0.2 mm, approximately 0.3 mm, approximately 0.4 mm or approximately 0.5 mm, as measured in a relaxed state with a drop gauge weighted with a presser foot.In a representative example, the sealing element may have a thickness of approximately 1.5 mm when fixed to... Petition 870260077472, dated 04 / 08 / 2026, page 49 / 91 39 / 42 a prosthetic valve frame in the relaxed state. The textured filaments 516 and loosely packed weft yarns 514 in the relaxed state can also promote tissue growth in the sealing element 500.

[0153] When the fabric is in the relaxed state, the textured filaments 516 of the weft yarns 514 can be widely dispersed, so that the individual weft yarns are not easily distinguished, as represented in Figure 43 A. When tensioned in the axial direction, the filaments 516 of the weft yarns 514 can be pulled together as the weft yarns lengthen and the folds, twists, etc. of the filaments are pulled straight, so that the fabric is stretched and the thickness decreases. In certain embodiments, when sufficient tension is applied to the fabric in the axial direction (the weft direction in the illustrated embodiment), such as when the prosthetic valve is pleated on a shaft of a delivery device, the textured fibers 516 can be pulled together so that the individual weft yarns 514 become distinguishable, as best shown in Figures 43B.

[0154] Thus, for example, when fully stretched, the sealing element may have a second thickness t3, as shown in Figure 44B, which is less than the thickness h. In certain embodiments, the thickness of the tensioned weft yarns 514 may be the same or nearly the same as the thickness t1 of the warp yarns 512. Thus, in certain examples, when stretched, the fabric may have a thickness equal to or nearly equal to three times the thickness t1 of the warp yarns 512, depending, for example, on the amount of flattening of the weft yarns 514. Therefore, in the example above, in which the warp yarns 512 have a thickness of approximately 0.06 mm, the thickness of the sealing element may vary from approximately 0.2 mm to about 1.5 mm as the fabric stretches and relaxes. In other words, the thickness of the fabric may vary by 750% or more as you stretch and relax it.

[0155] Furthermore, as shown in Figure 44A, the warp yarns 512 can be spaced apart from each other in the fabric by a distance y1 when the outer covering is in a relaxed state. As shown in Figures 43B and 44B, when tension is applied to the fabric in a direction perpendicular to the warp yarns 512 and parallel to the weft yarns 514, the distance between the warp yarns 512 can increase as the weft yarns 514 are elongated. In the example illustrated in Figure 44B, where the fabric has been stretched so that the weft yarns 514 have been Petition 870260077472, dated 04 / 08 / 2026, pp. 50 / 91 40 / 42 elongated and narrowed to approximately the diameter of the 512 warp yarns, the distance between the 512 warp yarns can increase to a new distance y2 which is greater than the distance y1.

[0156] In certain embodiments, the distance y1 may be, for example, approximately 1 mm to approximately 10 mm, approximately 2 mm to approximately 8 mm, or approximately 3 mm to approximately 5 mm. In a representative example, the distance y1 may be approximately 3 mm. In some embodiments, when the tissue is stretched as in Figures 43B and 44B, the distance y2 may be approximately 6 mm to approximately 10 mm. Thus, in certain embodiments, the length of the sealing element 500 in the axial direction may vary by 100% or more between the relaxed length L1 and the fully stretched length (e.g., L2). The ability of the tissue to elongate in this manner facilitates the folding of the prosthetic valve. Thus, the 500 sealing element can be soft and bulky when the prosthetic valve is expanded to its functional size and relatively thin when the prosthetic valve is crimped to minimize the overall crimping profile of the prosthetic valve. General Considerations

[0157] It should be understood that the modalities described can be adapted to deliver and implant prosthetic devices in any of the native rings of the heart (e.g., the pulmonary, mitral, and tricuspid rings) and can be used with any of several approaches (e.g., retrograde, antegrade, transseptal, transventricular, transatrial, etc.). The modalities described can also be used to implant prostheses in other lumens of the body. Additionally, besides prosthetic valves, the delivery set modalities described in this document can be adapted to deliver and implant various other prosthetic devices, such as stents and / or other prosthetic repair devices.

[0158] For the purposes of this description, certain aspects, advantages, and novel features of the embodiments of the present descriptive memorandum are described in this document. The methods, apparatus, and systems described should not be interpreted as limiting in any way. Instead, the present invention is directed to all the novel and non-obvious features and aspects of the various embodiments described, alone and in various combinations and sub-combinations with each other. The methods, Petition 870260077472, dated 04 / 08 / 2026, pp. 51 / 91 41 / 42 devices and systems are not limited to any specific aspect or feature or combination thereof, nor do the described modalities require that any one or more specific advantages be present or that the problems be solved.

[0159] Although the operations of some of the described modalities are described in a specific sequential order for convenient presentation, it should be understood that this manner of description encompasses rearrangement unless a specific order is required by the specific language set forth below. For example, operations described sequentially may, in some cases, be rearranged or executed concurrently. Furthermore, for the sake of simplicity, the attached figures may not show the various ways in which the described methods can be used in conjunction with other methods. Additionally, the description sometimes uses terms such as provide or achieve to describe the described methods. These terms are high-level abstractions of the actual operations that are performed. The actual operations that correspond to these terms may vary depending on the specific implementation and are easily discernible by a specialist in the technique.

[0160] As used in this application and claims, the singular forms a, an and the include the plural forms unless the context clearly indicates otherwise. Furthermore, the term includes means comprises. Additionally, the terms coupled and associated generally mean electrically, electromagnetically and / or physically (e.g., mechanically or chemically) coupled or linked and do not exclude the presence of intermediate elements between the coupled or associated items, without specific contrary language.

[0161] As used herein, the term proximal refers to a position, direction, or part of a device that is closest to the user and furthest from the implantation site. As used herein, the term proximal refers to a position, direction, or part of a device that is furthest from the user and closest to the implantation site. Thus, for example, proximal movement of a device is movement of the device toward the user, while distal movement of the device is movement of the device away from the user. The terms longitudinal and axial refer to an axis extending in the proximal and axial directions. Petition 870260077472, dated 04 / 08 / 2026, page 52 / 91 42 / 42 distal, unless expressly defined otherwise.

[0162] As used herein, the terms integrally formed and unitary construction refer to a construction that does not include welds, fasteners, or other means of fastening separately formed material parts together.

[0163] As used in this document, operations that occur simultaneously or concomitantly generally occur at the same time as one another, although delays in the occurrence of one operation relative to another due to, for example, spacing, play or clearance between components in a mechanical coupling, such as threads, gears, etc., are expressly within the scope of the above terms, in the absence of specific contrary language.

[0164] In view of the many possible embodiments to which the principles of the invention described may be applied, it should be recognized that the embodiments illustrated are only preferred examples of the invention and should not be considered as limiting the scope of the invention. Instead, the scope of the invention is defined by the following claims. Therefore, everything that is within the scope and spirit of these claims has been claimed in the invention. Petition 870260077472, dated 04 / 08 / 2026, p. 53 / 91

Claims

1 / 3 CLAIMS 1. Prosthetic heart valve (10), characterized in that it comprises: an annular frame (12) comprising an inlet end and an outlet end and being radially compressible and expandable between a radially compressed configuration and a radially expanded configuration; a valve structure (14) positioned within the frame (12) and fixed thereto; and an external sealing element (18) mounted outside the frame (12) and adapted to seal against surrounding tissue when the prosthetic heart valve (10) is implanted within a patient's native heart valve ring, wherein when the prosthetic valve (10) is in its radially expanded state, the external sealing element (18) fits snugly against the outer surface of the frame (12); wherein the external sealing element (18) is configured to stretch axially when the structure (12) is radially compressed to the radially compressed state;wherein the external sealing element (18) comprises a fabric or mesh, wherein the fabric is resiliently elastic between a first relaxed configuration and a second axially tensioned configuration, wherein the relaxed configuration corresponds to the radially expanded configuration of the prosthetic valve (10), and wherein the axially tensioned configuration corresponds to the radially compressed delivery configuration of the prosthetic valve (10).

2. Prosthetic heart valve (10), according to claim 1, characterized in that the structure (12) comprises a first row of angular struts (22) arranged end to end and extending circumferentially at the entry end of the structure (12), a second row of angular struts extending circumferentially (24), a third row of angular struts extending circumferentially (26), a fourth row of angular struts extending circumferentially (28), and a fifth row of angular struts extending circumferentially (32) at the exit end of the structure, wherein the fifth row of angular struts (32) is connected to Petition 870260077472, dated 04 / 08 / 2026, page.54 / 91 2 / 3 fourth row of angle braces (28) by a plurality of axially extending window frame parts (30) and a plurality of axially extending braces (31), wherein each axial brace (31) and each window frame part (30) extend from a location defined by the convergence of the lower ends of two angle braces (32) of the fifth row to another location defined by the convergence of the upper ends of two angle braces (28) of the fourth row.

3. Prosthetic heart valve (10), according to claim 2, characterized in that the external sealing element (18) comprises a straight entry edge part (160) and an exit edge part (162) that defines a plurality of alternating projections (164) and notches (166) that follow the shape of a row of frame struts (12).

4. Prosthetic heart valve (10), according to claim 3, characterized in that the external sealing element (18) extends from the inlet end of the structure (12) to the second row of struts (24).

5. Prosthetic heart valve (10), according to claim 3, characterized in that the external sealing element (18) extends from the inlet end of the structure (12) to the third row of struts (26).

6. Prosthetic heart valve (10), according to claim 3, characterized in that the external sealing element (18) extends from the inlet end of the structure (12) to the fourth row of struts (28).

7. Prosthetic heart valve (10), according to claim 3, characterized in that the inlet edge portion (160) is sutured to the first row of angled struts (22) with sutures (182), and the outlet edge portion (162) is sutured to the second row of struts (24), to the third row of struts (26) or to the fourth row of struts (28) with sutures (184).

8. Prosthetic heart valve (10) according to any of the preceding claims, characterized in that it further comprises an inner skirt (16) mounted on an inner surface of the structure (12), the inner skirt (16) having an inlet end portion that is attached to an inlet end portion of the outer sealing element (18).

9. Prosthetic heart valve according to claim 8, characterized in that the inlet end part of the inner skirt (16) Petition 870260077472, dated 04 / 08 / 2026, page 55 / 91 3 / 3 is wrapped around an inlet end of the structure (12) and overlaps the inlet end part of the outer sealing element (18) on the outside of the structure (12).

10. Prosthetic heart valve (10) according to any of the preceding claims, characterized in that the lower edge of the leaflet structure (14) has a wavy, curved and cut shape.

11. Prosthetic heart valve (10) according to claim 1, characterized in that the fabric comprises a plurality of circumferentially extending warp yarns (512) and a plurality of axially extending weft yarns (514).

12. Prosthetic heart valve (10) according to claim 11, characterized in that the weft yarns (514) are textured yarns comprising a plurality of textured filaments (516).

13. Prosthetic heart valve (10) according to claim 12, characterized in that when the weft yarns (514) are in a relaxed and tension-free state, the filaments (516) are loosely packed and provide compressible bulk or volume to the tissue.

14. Prosthetic heart valve (10) according to claim 13, characterized in that the thickness of the tensioned weft yarns (514) is the same or nearly the same as the thickness of the warp yarns (512). Petition 870260077472, dated 04 / 08 / 2026, p. 56 / 91

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