Multi-frame prosthetic heart valve

Abstract

To provide a durable prosthetic valve that may be delivered either surgically or endovascularly.SOLUTION: A prosthetic valve comprises: a frame defining a generally tubular shape and including frame members defining an opened pattern of meshes, where the opened pattern of meshes includes a plurality of windows and a plurality of circumferentially extending rows of meshes, the windows each have a first width, each mesh of the circumferentially extending rows of meshes has a second width, the first width is at least twice the second width, and the first and second widths are defined in the circumferential direction; and a plurality of leaflets formed of a single sheet of material and extending from the frame.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 61 / 739,721, filed December 19, 2012, the contents of which are incorporated herein by reference in their entirety.

[0002] The present disclosure relates generally to prosthetic valves, and more specifically to synthetic flexible leaflet-type prosthetic valve devices, systems and methods. [Background technology]

[0003] Biological valves have been developed to mimic the function and performance of natural valves. Flexible leaflets are fabricated from biological tissue, e.g., bovine pericardium. In some valve designs, the biological tissue is sewn to a relatively stiff frame that supports the leaflets, providing dimensional stability during implantation. Although biological valves can provide excellent short-term hemodynamic and biomechanical performance, they are prone to calcification and cusp rupture, among other failure conditions, requiring reoperation and replacement.

[0004] Attempts have been made to create more durable and flexible leaflet valves (referred to herein as synthetic leaflet valves (SLVs)) by using synthetic materials, such as polyurethanes in particular, as substitutes for biological tissue. However, synthetic leaflet valves have not been a viable option for valve replacement, primarily due to suboptimal designs and a lack of durable synthetic materials that result in premature failure.

[0005] A number of manufacturing techniques have been used to connect the leaflets to the frame, including sewing the individual leaflets to the frame (bio-based and synthetic) and, for synthetic leaflets only, injection molding and dip coating the frame with a polymer. In many cases, the resulting leaflets are supported on the frame and constitute flaps with an attachment edge that connects the leaflet to the frame and a free edge that allows movement of the flap.

[0006] The leaflets move under the influence of fluid pressure. In operation, the leaflets open when the upstream fluid pressure exceeds the downstream fluid pressure and close when the downstream fluid pressure exceeds the upstream fluid pressure. The free edges of the leaflets come together under the influence of the downstream fluid pressure to close the valve and prevent downstream blood from flowing backward through the valve.

[0007] The durability of a valve under cyclic loading of the leaflets opening and closing depends in part on the distribution of the load between the leaflets and the frame. Furthermore, when in the closed position, significant loads are placed on the leaflets. For example, mechanical failure of the leaflets can occur at the attachment edges where the relatively stiff frame supports the flexible leaflets. The cyclic loading of the leaflets opening and closing can lead to material failure due to fatigue, creep or other processes and depends in part on the leaflet material. Mechanical failure at the attachment edges is particularly common with synthetic leaflets.

[0008] The durability of a valve leaflet is also a function of, but not limited to, the bending characteristics of the leaflet during the opening and closing cycle. Small radius bends, creases and cross wrinkles can create high stress areas in the leaflet. These high stress areas can lead to the formation of holes and tears under repeated loading.

[0009] Biological valves may be delivered using surgical or transcatheter techniques. Surgical biological valves are implanted in patients using open heart surgery techniques. Surgical valves are typically manufactured to have a fixed diameter, in contrast to transcatheter valves, which must be in a range of diameters for access and delivery. Surgical valves are typically provided with a sewing cuff around the valve periphery to allow for sewing to the natural tissue opening. Sewing cuffs are well known in the art.

[0010] Transcatheter prosthetic valves are delivered through blood vessels via catheters, which helps minimize trauma to the patient compared to open-heart surgery, which causes extensive trauma to the patient, resulting in high morbidity and long recovery times. Valves delivered to the implantation site via catheter avoid the trauma of open-heart surgery and may be used in patients who are too sick or debilitated to tolerate open-heart surgery.

[0011] Some transcatheter valves comprise flexible leaflets mounted inside a tubular metal frame. The metal frame may be self-expanding or balloon-expandable from a compressed diameter before deployment to a functional diameter after deployment. The diameter of the delivery system depends in part on the resulting thickness of the valve leaflets compressed within the frame when loaded into the delivery catheter. In addition to the valve durability issues discussed above, transcatheter valves must also be able to withstand the handling and deployment stresses associated with being compressed and expanded.

[0012] A transcatheter valve must be capable of securely coupling to a tissue opening at the implantation site after placement within a blood vessel, e.g., so that the valve does not become dislodged or migrate after placement. Coupling of the valve to the implantation site is typically assisted by the relatively high hoop strength of a frame that is placed in biased engagement with the tissue opening.

[0013] There is a need for durable prosthetic valves that can be delivered surgically or intravascularly. Summary of the Invention

[0014] The described embodiments are directed to devices, systems and methods for valve replacement, such as heart valve replacement. More specifically, the described embodiments are directed to flexible leaflet valve devices and systems having a multi-piece support member or frame, and methods of manufacturing and delivering the valve devices.

[0015] In one embodiment, the prosthetic valve comprises a leaflet frame, an outer frame, and a film. The leaflet frame has a generally tubular shape defining a plurality of leaflet windows. The outer frame has a generally tubular shape. The leaflet frame is at least partially coaxially disposed within the outer frame. The leaflet frame and the outer frame are at least partially connected by an abutment of the film. At least a portion of the abutment of the film is received between and connects the leaflet frame and the outer frame to prevent relative movement and contact between the leaflet frame and the outer frame. The film defines a leaflet extending from each leaflet window.

[0016] In one embodiment, the prosthetic valve comprises a leaflet frame, an outer frame, and a film. The leaflet frame has a generally tubular shape defining a plurality of leaflet windows. The outer frame has a generally tubular shape. The leaflet frame is at least partially coaxially disposed within the outer frame. The outer frame includes frame elements that overlie the leaflet windows defined by the leaflet frame in a cooperative arrangement to provide structural support to the leaflet windows. The film defines a leaflet extending from each leaflet window.

[0017] In one embodiment, a method of making a prosthetic valve includes: wrapping a first layer of film in a tubular shape around a mandrel; providing a generally tubular leaflet frame, the leaflet frame having a leaflet frame leaflet surface and a leaflet frame outer surface, the leaflet frame defining a plurality of leaflet windows having window tops; providing a generally tubular outer frame, the outer frame having an outer frame leaflet surface and an outer frame outer surface; placing the leaflet frame and the outer frame on the first layer of film such that the leaflet frame and the outer frame are spaced apart from one another to define a bridge therebetween, the leaflet frame inner surface and the outer frame inner surface contacting the first layer of film; forming a second layer of film on the leaflet frame and the outer frame in contact with the leaflet frame outer surface and the outer frame outer surface; connecting the first layer of film and the second layer of film to one another and to the leaflet frame and the outer frame; forming the first layer of film and the second layer of film on the leaflet frame and the outer frame such that a leaflet free edge is defined therebetween. cutting the window upper portion transversely within the leaflet window so as to allow the leaflet to be positioned within the leaflet window; masking with release material a portion of the film disposed within the leaflet window defining the leaflet to prevent further bonding of the leaflet during subsequent processing steps; tubularly winding a third layer of film over the second layer of film and the release material on the leaflet window such that the third layer of film overlaps the leaflet frame, the outer frame and the bridge portion between the leaflet frame and the outer frame; connecting the third layer of film and the second layer of film to one another; removing the assembly from the mandrel; coaxially and at least partially placing the leaflet frame within the outer frame to at least partially fold and overlap the bridge portion so that the bridge portion is received between the leaflet frame and the outer frame; returning the assembly to the mandrel; and connecting the bridge portion to itself and to the third layer adjacent the outer surface of the leaflet frame and the first layer adjacent the inner surface of the outer frame in a nesting engagement. [Brief description of the drawings]

[0018] The accompanying drawings are included to provide a further understanding of the disclosure, are incorporated in and constitute a part of this specification, illustrate embodiments described herein, and together with the content herein serve to explain the principles discussed in the present disclosure. [Figure 1A] FIG. 2 is a side view of an embodiment of a valve. [Figure 1B] FIG. 1B is a side view of the embodiment of the valve of FIG. 1A. [Figure 1C] FIG. 1B is a perspective view of an embodiment of the valve of FIG. 1A. [Figure 1D] FIG. 2 is a diagram of the valve in an expanded position. [Figure 1E] FIG. 2 is a diagram of the valve in a compressed position. [Figure 2A] FIG. 1B is a view of the valve embodiment of FIG. 1A unfolded and flat. [Figure 2B] FIG. 1B is an exploded view of the valve embodiment of FIG. 1A unfolded and flat. [Figure 3A] FIG. 1B is an axial or top view of the valve embodiment of FIG. 1A in an open configuration. [Figure 3B] FIG. 1B is an axial or top view of the valve embodiment of FIG. 1A in a closed configuration. [Figure 4A] FIG. 1 is a side view of an embodiment of a transcatheter delivery system within an anatomical structure. [Figure 4B] FIG. 1 is a side view of an embodiment of a surgical valve within an anatomical structure. [Figure 5A] 1A-1C are cross-sectional views of an embodiment of a valve during manufacture. [Figure 5B] 1 is a cross-sectional view of an embodiment of a valve. [Figure 6A] FIG. 13 illustrates an embodiment of an outer frame unfolded and flat. [Figure 6B] FIG. 13 illustrates an embodiment of an outer frame unfolded and flat. [Figure 7A] FIG. 2 illustrates an embodiment of a leaflet frame unfolded and flat. [Figure 7B] FIG. 2 illustrates an embodiment of a leaflet frame unfolded and flat. [Figure 8A] FIG. 2 illustrates an embodiment of a leaflet frame unfolded and flat. [Figure 8B] FIG. 2 illustrates an embodiment of a leaflet frame unfolded and flat. [Figure 8C] FIG. 2 illustrates an embodiment of a leaflet frame unfolded and flat. [Figure 8D] FIG. 2 illustrates an embodiment of a leaflet frame unfolded and flat. [Figure 8E] FIG. 2 illustrates an embodiment of a leaflet frame unfolded and flat. [Figure 9A] FIG. 1 is a side view of a valve component on an assembly mandrel in an embodiment. [Figure 9B] FIG. 1 is a side view of a valve component on an assembly mandrel in an embodiment. [Figure 10A] FIG. 2 is a lateral exploded view of another embodiment of a prosthetic valve including a generally tubular leaflet frame and a generally tubular outer frame connected by a mechanical engagement member. [Figure 10B] FIG. 10B is an assembled view of the embodiment of FIG. 10A. [Figure 11A] FIG. 2 is a side view of an embodiment of a valve. [Figure 11B] FIG. 11B is a perspective view of the valve embodiment of FIG. [Figure 12] FIG. 13 is a side view of a leaflet frame on an assembly mandrel in one embodiment. [Figure 13A] FIG. 13 is a side view of a leaflet frame on a cutting mandrel in one embodiment. [Figure 13B] FIG. 13B is a perspective view of a leaflet frame on the cutting mandrel of FIG. 13A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Those skilled in the art will readily appreciate that the various aspects of the present disclosure can be implemented in a number of methods and devices configured to perform the intended functions. In other words, other methods and devices may be incorporated into the present invention to perform the intended functions. It should also be noted that the accompanying drawings referred to herein are not necessarily drawn to scale, and emphasis may be placed on illustrating the various aspects of the present disclosure. In this regard, the drawings should not be construed as limiting.

[0020] Although embodiments herein are described in conjunction with various principles and concepts, the described embodiments should not be bound by theory. For example, embodiments are described herein in conjunction with prosthetic valves, and more specifically, prosthetic heart valves. However, embodiments within the scope of the present disclosure may also be applied to valves or mechanisms of similar structure and / or function. Additionally, embodiments within the scope of the present disclosure may also be applied to non-cardiac applications.

[0021] The term "leaflet" as used herein in the context of prosthetic valves is a component of a one-way valve that is movable between an open position and a closed position under the influence of a pressure differential. When in the open position, the leaflet allows blood to flow through the valve. When in the closed position, the leaflet substantially blocks backflow through the valve. In embodiments with multiple leaflets, each leaflet cooperates with at least one adjacent leaflet to block backflow of blood. A pressure differential in the blood is caused, for example, by contraction of the ventricles or atria of the heart, and such a pressure differential typically occurs when the leaflet is closed due to increased fluid pressure on one side of the leaflet. When the pressure on the inflow side of the valve becomes higher than the pressure on the outflow side of the valve, the leaflet opens and blood flows through the valve. As blood flows through the valve into an adjacent heart chamber or blood vessel, the pressure on the inflow side becomes equal to the pressure on the outflow side. When the pressure on the outflow side of the valve becomes higher than the blood pressure on the inflow side of the valve, the leaflet returns to the closed position, generally preventing blood from flowing back through the valve.

[0022] As used herein, the term "film" refers to a sheet of material comprising a single composition, such as, but not limited to, expanded fluoropolymer.

[0023] The term "composite" as used herein refers to a combination of an expanded fluoropolymer membrane and an elastomer, such as, but not limited to, a fluoroelastomer, which may be impregnated into the porous structure of the membrane, coated on one or both sides of the membrane, or a combination thereof, both coated on and impregnated into the membrane.

[0024] As used herein, the term "laminate" refers to multiple layers of films, composites or other materials, such as elastomers, and combinations thereof.

[0025] As used herein, the term "film" refers generically to one or more of a membrane, a composite, or a laminate.

[0026] As used herein, the term "biocompatible material" refers generally to films or biological materials, such as, but not limited to, bovine pericardium.

[0027] The term "leaflet window" is defined as the space defined by the frame and into which the leaflets extend. The leaflets may extend from the frame element or may extend adjacent to but spaced from the frame element.

[0028] The term "native valve orifice and tissue orifice" refers to anatomical structures in which a prosthetic valve may be placed. Such anatomical structures include, but are not limited to, locations where a heart valve has or has not been surgically removed. It is understood that other anatomical structures that may receive a prosthetic valve include, but are not limited to, veins, arteries, ducts, and shunts. Although reference is made herein to replacing a natural valve with a prosthetic valve, it is understood that a valve orifice or implantation site may also refer to a location in a synthetic or biological conduit that may receive a valve for a particular purpose. Thus, the scope of the embodiments described herein is not limited to valve replacement.

[0029] As used herein, "couple" means to join, connect, attach, attach, affix or adhere, whether directly or indirectly, and whether permanently or temporarily.

[0030] Embodiments herein include various devices, systems and methods for surgical and catheter-based placement of prosthetic valves suitable for, for example, but not limited to, heart valve replacement, which operate as one-way valves, defining a valve opening into which leaflets open to allow blood flow and close to block the valve opening in response to differential fluid pressure.

[0031] The embodiments described herein represent advances in prosthetic valve technology related to, but not limited to, mechanical and biological performance advantages. In some embodiments described herein, the prosthetic valve comprises two frames connected by an adjacent film, where the leaflet frame is nested within the outer frame in a telescopic manner, such that the valve does not leak between the leaflet frame and the outer frame.

[0032] Typically, the leaflets of a flexible leaflet-type prosthetic heart valve are sewn directly to the frame. In an alternative configuration, the leaflet material can be attached to the inside of the frame, but this arrangement can lead to the leaflet material peeling off if not adequately adhered. In another configuration, the leaflet material can be attached to the outside of the frame, but this arrangement often leads to issues with the leaflets wearing on the frame. In the embodiments described herein, these issues are avoided by using a pair of frames with the leaflet material contained between them. In the embodiments described herein, the pair of frames can be compressed and re-expanded while still retaining their original shape relative to each other, allowing for transcatheter delivery.

[0033] In some embodiments described herein, the prosthetic valve comprises two frames: a leaflet frame and an outer frame. The film defining the leaflets may be coupled to the inner surface of the leaflet frame. In some other embodiments, the film defining the leaflets is contained between the leaflet frame and the outer frame and spans the leaflet window defined by the leaflet frame. Thus, because the leaflets are contained between the leaflet frame and the outer frame, peeling or delamination of the leaflets is largely prevented compared to when the leaflets are coupled only to the inner surface of the leaflet frame.

[0034] In some embodiments described herein, the prosthetic valve comprises two frames, a leaflet frame and an outer frame, which are separated from each other by a film, in other words, a metal / polymer / metal interconnect, with no metal-to-metal contact between the two frames.

[0035] In some embodiments described herein, the prosthetic valve comprises two frames, a leaflet frame and an outer frame. The leaflet frame fits within the outer frame, and the leaflet frame and the outer frame cooperate to provide a relatively high resistance, particularly to plate compression. In some embodiments, the outer frame provides structural support for the leaflet window by providing frame elements that overlap the leaflet window defined by the leaflet frame. In some embodiments, the outer frame provides frame elements that overlap the leaflet window defined by the leaflet frame to prevent tissue from ingressing into the leaflet window upon implantation. In some embodiments, the outer frame provides frame elements that overlap the leaflet window defined by the leaflet frame and cooperate to allow uniform compression and expansion of the frame assembly in the case of transcatheter embodiments.

[0036] In some embodiments described herein, the prosthetic valve comprises two frames, a leaflet frame and an outer frame. The leaflet frame defines a leaflet window, which in part forms the shape of the leaflet. In some embodiments, the leaflet comprises a flat base from which the leaflet bends toward the free edge of the leaflet with minimal creases and flutter. In some embodiments, the leaflet comprises a flat base that, among other things, defines one or more shorter valve lengths, which substantially prevents blood stagnation and pooling at the base and facilitates flushing, as compared to leaflets having rounded bases.

[0037] In some embodiments described herein, the prosthetic valve comprises two frames: a leaflet frame and an outer frame. The leaflet frame defines a leaflet window from which the leaflets extend. The leaflets are defined by the intersection of films forming overlap regions to at least partially define the leaflet base and / or leaflet sides.

[0038] valve FIG. 1A is a side view of a valve 100 according to an embodiment. FIG. 1B is also a side view of the valve 100 of FIG. 1A rotated 60° about the longitudinal axis X. FIG. 1C is a perspective view of the valve 100 of FIG. 1A. FIG. 2A is a side view of the valve 100 of FIG. 1A, cut longitudinally to better illustrate the generally tubular elements of the valve 100. FIG. 2B is an exploded view of the embodiment of FIG. 2A. FIGS. 3A and 3B are axial views of the valve 100 of FIG. 1A in open and closed positions, respectively. In FIG. 3B, the leaflets 140 are depicted slightly open to better illustrate their features, but in a fully closed valve 100, the leaflet free edges 142 of the leaflets 140 come together under the influence of downstream fluid pressure to close the valve and prevent downstream blood from backflowing through the valve.

[0039] Valve 100 comprises an outer frame 120, a leaflet frame 130, and a film 160 that covers and connects the outer frame 120 to the leaflet frame 130 and comprises the leaflets 140. Embodiments of valve 100 are discussed further in connection with transcatheter valves that may be compressed and re-expanded. Embodiments of valve 100 are also applicable to surgical valves with the addition of a soling cuff 170, as shown in FIG. 4B. Leaflet frame and outer frame configurations relevant to embodiments where the valve is a fixed diameter surgical valve only are discussed in other embodiments later in this disclosure.

[0040] In one embodiment, the prosthetic valve comprises a leaflet frame 130 having a generally tubular shape, an outer frame 120 having a generally tubular shape, and a film 160. The leaflet frame 130 is at least partially coaxially disposed within the outer frame 120. The outer frame 120 provides structural support to the leaflet windows defined by the leaflet frame 130 by providing a frame element that overlies the leaflet windows, as shown in Figures 1A-1B. The leaflet frame 130 defines a plurality of leaflet windows, and the film 160 defines a leaflet extending from each leaflet window.

[0041] Outer frame In one embodiment, the outer frame 120 is a generally tubular member that describes a generally open pattern of mesh 122. In a transcatheter embodiment, the outer frame 120 can be compressed and expanded between different diameters. The outer frame 120 includes an outer frame first end 121a and an outer frame second end 121b opposite the outer frame first end 121a. The outer frame 120 includes an outer frame outer surface 126a and an outer frame inner surface 126b opposite the outer frame outer surface 126a, as shown in FIG. 5A. The outer frame 120 can include a structure known in the art as a stent. A stent is a tubular member that can have a small diameter suitable for percutaneous transcatheter delivery to an anatomical structure and can expand to a larger diameter when deployed into the anatomical structure. Stents of various designs and material properties are well known in the art.

[0042] For example, as shown in the embodiment of Figures 1A-1C and 2A-2B, valve 100 includes an outer frame 120 that defines a stent having mesh 122 that has a generally diamond shape when in a large diameter configuration, as generally shown in Figure 1D. When compressed to a smaller diameter, mesh 122 deforms to a generally elongated diamond shape, as generally shown in Figure 1E. When re-expanded to a larger diameter, mesh 122 re-expands to once again assume a generally diamond shape.

[0043] 6A and 6B are side views of alternative embodiment outer frames 120a and 120b, cut longitudinally through the outer frames to better illustrate the elements of the outer frames. Of course, there are numerous outer frame embodiments having configurations suitable for particular purposes.

[0044] The open framework of the stent may repeat or otherwise vary in pattern, for example, a geometric shape and / or a series of straight or sinuous lines. The geometric shape may include any shape that facilitates substantially uniform circumferential compression and expansion. The outer frame 120 may comprise a cut tube or other element suitable for a particular purpose. The outer frame 120 may be etched, cut, laser cut, or punched into a tube or sheet of material, and the sheet then formed into a substantially cylindrical structure. Alternatively, an elongated material, such as a wire, bendable strip, or a combination thereof, may be bent or braided into a substantially cylindrical structure, with the walls of the cylinder comprising an open framework that is generally uniformly circumferentially compressible to a small diameter and expandable to a larger diameter.

[0045] It is known that stents of various designs can be elastically deformable so that they can self-expand under a spring load. It is also known that stents of various designs can be plastically deformable so that they can be mechanically expanded, for example using a balloon. Stents of various designs are also known that are plastically deformable as well as elastically deformable. The embodiments of the outer frame 120 described herein are not limited to any particular stent design or mode of expansion.

[0046] The outer frame 120 may comprise any metallic or polymeric biocompatible material. For example, the outer frame 120 may comprise materials such as, but not limited to, Nitinol, cobalt-nickel alloy, stainless steel, polypropylene, acetyl homopolymer, acetyl copolymer, ePTFE, other alloys or polymers, or other biocompatible materials that have sufficient physical and mechanical properties to function as described herein.

[0047] In embodiments, the outer frame 120 and / or leaflet frame 130 may be configured to positively engage an implantation site to securely anchor the valve 100 at the site, as shown in FIG. 4A depicting transcatheter deployment of the valve 100. In one embodiment, the outer frame 120 may comprise a sufficiently stiff frame with low elastic bounce to maintain sufficient apposition to the tissue opening 150 to hold position. In another embodiment, the outer frame 120 and / or leaflet frame 130 may be configured to expand to a diameter larger than the tissue opening 150 to allow the valve 100 to expand into the tissue opening 150 to seat the valve 100 securely within the opening 150. In another embodiment, the outer frame 120 may comprise one or more anchors (not shown) configured to engage an implantation site, such as the tissue opening 150, to secure the valve at the implantation site.

[0048] Of course, other elements or means for connecting the valve 100 to the implantation site are contemplated, for example, but not limited to, other means may be used to connect the valve 100 to an artificial or biological conduit, including mechanical and adhesive means.

[0049] Leaflet Frame 1C and 2B, in one embodiment, the leaflet frame 130 is a generally tubular member defining a plurality of leaflet windows 137 connected by frame elements 139. The leaflet frame 130 includes a leaflet frame first end 138a and a leaflet frame second end 138b opposite the leaflet frame first end 138a. As shown in FIGS. 5A and 3A, the leaflet frame 130 includes a leaflet frame outer surface 132a and a leaflet frame inner surface 132b opposite the leaflet frame outer surface 132a. The leaflet frame first end 138a and the leaflet frame second end 138b are generally zig-zag shaped to facilitate bending about a bend point 136 and to facilitate compression and expansion between different diameters when compressed onto a delivery device and expanded by a balloon for the transcatheter valve 100 embodiments, as generally described with respect to the outer frame 120. As described below, surgical valve 100 embodiments may or may not have a zigzag configuration, since surgical valve 100 may be of a fixed diameter and does not require compression and re-expansion.

[0050] The leaflet frame 130 may also be referred to in a general sense as a stent or frame. As used herein, the term "frame element" 139 refers to any portion of the leaflet frame 130 or outer frame 120, such as, but not limited to, the individual portions that define the leaflet windows 137 or mesh 122.

[0051] The leaflet frame 130, in one embodiment, follows a predetermined repeating pattern as shown in FIG. 2B. The leaflet frame 130 defines three interconnected leaflet windows 137 that are substantially triangular. Each leaflet window 137 includes two leaflet window sides 133, including posts 131, a leaflet window base 134, and a leaflet window top 135. In this embodiment, the leaflet window base 134 defines a bend point 136, which will be described below. The leaflet window sides 133 and leaflet window top 135 of one leaflet window 137 are interconnected with the leaflet window sides 133 of an adjacent leaflet window 137 at posts 131.

[0052] The leaflet frame 130 may be patterned with a variety of patterns and geometries that facilitate substantially uniform circumferential compression and expansion. The leaflet frame 130 may comprise a cut tube or other element suitable for a particular purpose. The leaflet frame 130 may be etched, cut, laser cut, or stamped into a tube or sheet of material, and then the sheet formed into a substantially cylindrical structure. Alternatively, an elongated material, such as a wire, bendable strip, or a series of these, may be bent or braided into a substantially cylindrical structure, with the cylindrical walls comprising an open framework that is generally uniformly circumferentially compressible to a small diameter and expandable to a larger diameter.

[0053] The leaflet frame 130 may comprise any metallic or polymeric biocompatible material. For example, the leaflet frame 130 may comprise a material, such as, but not limited to, Nitinol, cobalt-nickel alloy, stainless steel, polypropylene, acetyl homopolymer, acetyl copolymer, ePTFE, other alloys or polymers, or other biocompatible materials that have sufficient physical and mechanical properties to function as described herein.

[0054] As described in more detail below, a film 160 is placed over each of the three leaflet windows 137 to form the leaflets 140. Further embodiments are described below in which the leaflet windows 137 have shapes other than a substantially triangular shape, with or without a leaflet window top 135, including, but not limited to, parabolic, trapezoidal, suitable for particular purposes of surgical and transcatheter valve 100 embodiments.

[0055] 7A and 7B are side views of alternative embodiment leaflet frames 130a and 130b, cut open longitudinally to better illustrate the leaflet frame elements. Leaflet frame 130a includes a substantially triangular leaflet window 137a defining a pointed leaflet window base 134a. Leaflet frame 130b includes a substantially triangular leaflet window 137b defining a flat leaflet window base 134b that may be used to define the leaflet base.

[0056] 8A-8C are side views of alternative embodiment leaflet frames 130c-e, cut open longitudinally to better illustrate the leaflet frame elements. Leaflet frame 130c includes a substantially triangular leaflet window 137c that defines a pointed leaflet window base 134c. Leaflet frame 130d includes a substantially parabolic leaflet window 137d that defines a rounded leaflet window base 134d. A flat leaflet window base 134b may be used to define the leaflet base. Leaflet frame 130e includes a substantially triangular leaflet window 137e that defines a pointed leaflet window base 134e but does not have a leaflet window top.

[0057] FIG. 8D is a side view of an alternative embodiment of a leaflet frame 130f, cut longitudinally through the leaflet frame 130f to better illustrate the elements of the leaflet frame 130f of a valve substantially shown as the valve 100 of FIGS. 11A and 11B. The leaflet 140f is shown in dotted lines to indicate where it is located in the leaflet window 137f, which is defined by the leaflet window side 133f and the window base 134f. The two leaflet sides 141f diverge from the leaflet base 143f, which is substantially flat, with the leaflet free edge 142f on the opposite side of the leaflet base 143f, as shown by the dashed lines in FIG. 8D. The leaflet frame 130f further defines a post 1121 from which the leaflet free edge 142f extends.

[0058] FIG. 8E is a side view of an alternative embodiment of a leaflet frame 130g, cut open longitudinally to better illustrate the elements of the leaflet frame 130g. The dotted lines indicate where the leaflets 140g are located in the leaflet window 137g, which is defined by the leaflet window sides 133g and the window base 134g. The two leaflet sides 141g diverge from the leaflet base 143g, which is substantially flat, with the leaflet free edge 142g on the opposite side of the leaflet base 143g, as shown by the dashed lines in FIG. 8E. The leaflet frame 130g comprises a plurality of leaflet frame elements that define a plurality of isosceles triangles, which are interconnected by the leaflet window base 134g forming the leaflet window 137g that describes an isosceles rectangle. Each leaflet window side 133g is defined by one side of one triangle and one side of an adjacent triangle.

[0059] As discussed above, the leaflet window base may be used to define the leaflet base according to embodiments. As also discussed above, the leaflet base may be defined as the imaginary leaflet base 143a by the fold line 146 of the film 160 in the folding region away from the leaflet window base 134, as shown in Figures 1A and 1B, and as shown in dashed lines in Figure 2B. Of course, there are numerous outer frame embodiments having configurations suitable for a particular purpose.

[0060] In the transcatheter valve 100 embodiment, the leaflet frame 130 is compressible, either elastically, plastically, or both, to obtain a relatively small diameter that allows for percutaneous transcatheter loading and delivery. In the embodiment of FIG. 2B, the leaflet frame 130 may comprise one or more bend points 136 to provide preferential bending sites for the leaflet frame 130 to bend when compressed to a small diameter. The bend points 136 include sites on the leaflet frame 130 that experience the greatest degree of bending when transitioning from an expanded state to a collapsed state and vice versa. The bend points 136 may comprise, among other things, geometric, structural, or material changes that bias the leaflet frame 130 to bend at the bend points 136 upon compression.

[0061] The leaflet frame 130 may include, for example and without limitation, any elastically deformable metallic or polymeric biocompatible material according to embodiments. The leaflet frame 130 may include a shape memory material, such as Nitinol, a nickel-titanium alloy. Other materials suitable for the leaflet frame 130 include, but are not limited to, other titanium alloys, stainless steel, cobalt-nickel alloys, polypropylene, acetyl homopolymers, acetyl copolymers, other alloys or polymers, or other biocompatible materials that have sufficient physical and mechanical properties to function as the leaflet frame 130 as described herein.

[0062] In one embodiment, the leaflet frame 130 and the outer frame 120 comprise a shape memory material that flexes under load and retains its initial shape when the load is removed, allowing the leaflet frame 130 and the outer frame 120 to self-expand from a compressed shape to a pre-defined shape. The leaflet frame 130 and the outer frame 120 may comprise the same or different materials. In one embodiment, the leaflet frame 130 and the outer frame 120 are plastically deformable and balloon expandable. In another embodiment, the outer frame 120 and the leaflet frame 130 are elastically deformable such that they are self-expanding.

[0063] film The film 160 is generally any sheet-like material that is biocompatible and configured to couple to the outer frame 120 and the leaflet frame 130 depending on the embodiment. It is understood that the term "film" is used generically for one or more biocompatible materials suitable for a particular purpose. The leaflet 140 also comprises a film 160.

[0064] In some embodiments, the biocompatible material is not biologically derived but is sufficiently flexible and tough for a particular purpose, such as a biocompatible polymer, for example, the film 160. In some embodiments, the film 160 includes a biocompatible polymer in combination with an elastomer, referred to as a composite.

[0065] It is also understood that, depending on the embodiment, the film 160 coupled to the outer frame 120 may not be the same film 160 that is coupled to the leaflet frame 130. Details of the various types of films 160 are provided below. In some embodiments, the film 160 may be formed from a generally tubular material and at least partially covers the outer frame 120 and the leaflet frame 130. The film 160 may include one or more of a membrane, a composite, or a laminate. Details of the various types of films 160 are provided below.

[0066] Leaflet Each leaflet window 137 has attached thereto a biocompatible material, such as a film 160, which is connected to a portion of the leaflet window side 133, the film 160 defining a leaflet 140. In one embodiment, each leaflet 140 defines a leaflet free edge 142 and a leaflet base 143. It is contemplated that multiple embodiments of leaflet base configurations may be provided, as described below. In one embodiment, the film 160 is connected to a portion of the leaflet window side 133 and to the leaflet window base 134, such that the leaflet 140 is defined by that portion of the leaflet window side 133 and the leaflet window base 134. In another embodiment, the film 160 is connected to a portion of the leaflet window side 133 but not to the leaflet window base 134 of the leaflet frame 130, such that the leaflet 140 is defined by a virtual leaflet base 143a defined by that portion of the leaflet window side 133 and a folding region, as described below.

[0067] The shape of the leaflet 140 is determined in part by the shape of the leaflet window 137 and the leaflet free edge 142. In one embodiment, as described below, the shape of the leaflet 140 is also determined in part by a process that induces folding at fold lines 145 that define a virtual leaflet base 143a, as described below, to bring the leaflet 140 into a predefined shape. Due to the high bending stresses experienced by the leaflet base, defining a virtual leaflet base 143a that is unconstrained by the leaflet window base 134 may greatly reduce the likelihood of the leaflet 140 tearing at the interface between the leaflet base 143 and the leaflet window base 134. Additionally, blood pooling and stagnation at the leaflet base 143 may be reduced compared to a rounded leaflet base.

[0068] In one embodiment, as shown in Figure 3A, substantially the entire leaflet frame 130 is adjacent to the outer frame inner surface 126b. Thus, when the leaflets 140 are in a fully open position, the valve 100 exhibits a substantially circular valve opening 102, as shown in Figure 3A. When the leaflets 140 are in the open position, fluid can flow through the valve opening 102.

[0069] As the leaflets 140 switch between the open and closed positions, the leaflets 140 bend generally near the leaflet base 143 and at the leaflet window sides 133 where the leaflets join. When the valve 100 is closed, generally about half of each leaflet free edge 142 abuts the adjacent half of the leaflet free edge 142 of an adjacent leaflet 140, as shown in Figure 3B. The three leaflets 140 in the embodiment of Figure 3B meet at a tri-point 148. When the leaflets 140 are in the closed position, the valve opening 102 is blocked, stopping fluid flow.

[0070] 3B, in one embodiment, each leaflet 140 includes a central region 182 and two lateral regions 184 on either side of the central region 182. The two central region sides 183 converge from the leaflet base 143 toward the leaflet free edge 142. Each lateral region 184 has a substantially triangular shape, with each lateral region being defined by one of the central region sides 183, one of the leaflet sides 141, and the leaflet free edge 142.

[0071] Leaflets 140 may be configured to be actuated by a blood pressure differential, such as that caused by contraction of the ventricles or atria of the heart, which typically results from an increase in fluid pressure on one side of valve 100 when it is closed. When the pressure on the inflow side of valve 100 becomes greater than the pressure on the outflow side of valve 100, leaflets 140 open to allow blood to flow through the valve. As blood flows through valve 100 into an adjacent heart chamber or blood vessel, the pressures equalize. When the pressure on the outflow side of valve 100 becomes greater than the pressure on the inflow side of valve 100, leaflets 140 return to a closed position, generally preventing blood from flowing backwards through the inflow side of valve 100.

[0072] It will be appreciated that depending on the embodiment, the leaflet frame 130 may comprise any number of leaflet windows 137 and therefore leaflets 140 suitable for a particular purpose. Leaflet frames 130 with one, two, three or more leaflet windows 137 and corresponding leaflets 140 are contemplated.

[0073] Valve Film As shown in the exploded view of Figure 2B of the unfolded embodiment of Figure 2A, the outer frame 120 is substantially coplanar and laterally spaced adjacent to the leaflet frame 130. The leaflet window base 134 of the leaflet window 137 is located adjacent the outer frame first end 121a of the outer frame 120, and the leaflet frame first end 138a of the leaflet frame 130 extends away from the outer frame 120. As will be described below, this arrangement is also used in the manufacture of the valve 100. In this arrangement, a film 160 is connected to the outer frame 120 and a portion of the leaflet frame 130, and the film 160 connects the outer frame 120 to the leaflet frame 130.

[0074] The film 160 spanning the space between the outer frame 120 and the leaflet frame 130 at least partially defines a folding region 144, shown in dashed lines in Figure 2B. As described below, in one embodiment, the folding region 144 is provided such that the leaflet frame 130 is nested within the outer frame 120, which, in one embodiment of a method of manufacturing the valve 100, has an inner diameter that is greater than the outer diameter of the leaflet frame 130, thereby forming folds within the folding region 144 along generally circumferential lines 146.

[0075] Depending on the embodiment, it is contemplated that the film 160 may be coupled to the leaflet frame 130 and the outer frame 120 in a number of ways suitable for a particular purpose. In some embodiments, the outer frame 120 may be wrapped with an overlapping layer of film 160 having a first composition. The leaflet frame 130 may be wrapped with an overlapping layer of film 160 having a second composition. The wrapped leaflet frame 130, the wrapped outer frame 120, and the space between the outer frame 120 and the leaflet frame 130 may be wrapped with an overlapping layer of film 160 having a third composition that at least partially defines the fold region 144.

[0076] In another embodiment, the film 160 may be coupled to the inner or outer surfaces of the leaflet frame 130 and the outer frame 120. In another embodiment, the film 160 may be coupled to the inner and outer surfaces of the leaflet frame 130 and the outer frame 120, sandwiching the leaflet frame 130 and the outer frame 120 between the film 160. As will be described below, as shown in Figures 3A, 5A-5B, the film 160 may be coupled to at least the leaflet frame outer surface 132a and the outer frame inner surface 126b to provide additional support for the leaflet 140 and prevent it from becoming detached from the leaflet frame 130. This is because a portion of the film 160 is received between the leaflet frame 130 and the outer frame 120, as shown in Figure 5B.

[0077] Regardless of where film 160 is present, film 160 prevents blood from flowing through or past valve 100 except through the valve openings 102 and the uncovered portions of leaflet frame 130 or outer frame 120 when leaflets 140 are in the open position. Thus, film 160 forms a barrier to blood flow through the lattice or mesh 122 of outer frame 120 and leaflet frame 130 that it covers, as well as between outer frame 120 and leaflet frame 130.

[0078] The film 160 is secured or otherwise connected at one or more locations to the interior or exterior surfaces of the outer frame 120 and the leaflet frame 130, for example, using one or more of taping, heat shrinking, gluing, and other methods known in the art. In some embodiments, multiple membrane / composite layers, i.e., laminates, may be used and connected to both the interior and exterior surfaces of the outer frame 120 and the leaflet frame 130 to form at least a portion of the film 160.

[0079] The film 160 comprises any material having suitable physical and mechanical properties to perform the functions described herein. The film 160 may comprise the same materials as the leaflets 140, as described above, or different materials. Similarly, the material composition of the film 160 may be homogenous or non-homogeneous. Different portions of the film 160 may comprise different materials, which may impart different physical and mechanical properties to the film 160.

[0080] As shown in Figures 5A and 5B, both of which show elements in cross section, the leaflet frame 130 has a generally tubular shape that defines a plurality of leaflet windows (not shown). The outer frame 120 has a generally tubular shape. The leaflet frame 130 is at least partially coaxially disposed within the outer frame 120. The leaflet frame 130 and the outer frame 120 are at least partially connected by adjacent portions of the film 160. At least a portion of the adjacent portions of the film 160 are received between the leaflet frame 130 and the outer frame 120 and connect the leaflet frame 130 to the outer frame 120 so as not to move relative therebetween. The film defines a leaflet 140 extending from each leaflet window. A leaflet base 143 is defined by a fold line 145 of the film 160. In one embodiment, at least a portion of the adjacent portion of the film 160 contained between and connecting the leaflet frame 130 and the outer frame 120 prevents contact between the leaflet frame 130 and the outer frame 120 .

[0081] As mentioned above, in one embodiment of the method of manufacturing the valve 100, the leaflet frame 130 is placed within the outer frame 120 in a telescopic manner such that the film 160 is folded at the folding region 144, as shown in Figures 5A and 5B. The leaflet frame 130 is thus nested within the outer frame 120 while remaining coaxial therewith. Further processing of this assembly connects the folding region 144 to itself and the wrapped leaflet frame 130 and outer frame 120, while preventing the film 160 that comprises the leaflets 140 from adhering to unintended areas of the valve 100 where it may interfere with leaflet function.

[0082] In another embodiment, the frame members defining the meshes of the leaflet frame 130 and the outer frame 120 are aligned, preferably in an overlapping, complementary arrangement to provide structural rigidity to the assembly.

[0083] In one embodiment of the transcatheter valve 100, referring to Figures 1D-1E, the valve 100 may be compressed to a collapsed configuration having a small diameter and expanded to an expanded configuration. Thus, the valve 100 may be delivered through a vessel in the collapsed configuration and expanded upon deployment within a tissue opening 150, as shown in Figure 4A. The leaflet frame 130 and outer frame 120 may regain circumferential uniformity as they transition from the collapsed configuration to the expanded configuration.

[0084] The valve 100 may be loaded into a delivery catheter suitable for a particular purpose. The diameter of the valve 100 in the collapsed configuration is determined in part by the thickness of the leaflet frame 130 within the outer frame 120 and the thickness of the leaflets.

[0085] Leaflet Film The biocompatible material forming the leaflet 140 may include any biological tissue or synthetic biocompatible material that is sufficiently compliant and flexible, such as a biocompatible polymer. In one embodiment, the leaflet 140 includes a biocompatible polymer in combination with an elastomer, referred to as a composite. The material in one embodiment includes a composite including an expanded fluoropolymer membrane (with multiple voids within a matrix of fibrils) and an elastomeric material. It is understood that multiple types of fluoropolymer membranes and multiple types of elastomeric materials may be combined to form a laminate while remaining within the scope of the present disclosure. It is also understood that the elastomeric material may include multiple types of elastomers, multiple types of non-elastomeric components, such as inorganic fillers, therapeutic agents, radiopaque markers, and the like, while remaining within the scope of the present disclosure.

[0086] In some embodiments, the composite material includes an expanded fluoropolymer material formed from a porous ePTFE membrane, such as generally described in US Pat. No. 7,306,729 to Bacino.

[0087] The expandable fluoropolymer used to produce the described expanded fluoropolymer material may include PTFE homopolymer. In alternative embodiments, PTFE blends, expandable modified PTFE and / or expanded copolymers of PTFE may be used. Non-limiting examples of suitable fluoropolymer materials are described, for example, in U.S. Patent No. 5,708,044 to Branca, U.S. Patent No. 6,541,589 to Baillie, U.S. Patent No. 7,531,611 to Sabol et al., U.S. Patent Application No. 11 / 906,877 to Ford, and U.S. Patent Application No. 12 / 410,050 to Xu et al.

[0088] The expanded fluoropolymer membrane may have any suitable microstructure to obtain desired leaflet performance.In some embodiments, the expanded fluoropolymer has a microstructure of nodes interconnected by fibrils, as described, for example, in US Patent No. 3,953,566 to Gore. The fibrils radiate from the nodes in multiple directions, and the membrane has a generally homogeneous structure.Membranes with this microstructure may typically exhibit a matrix tensile strength ratio in two orthogonal directions of less than 2, and possibly less than 1.5.

[0089] In another embodiment, the expanded fluoropolymer membrane has a microstructure that is substantially entirely of microfibers, as generally taught in U.S. Patent No. 7,306,729 to Bacino. Expanded fluoropolymer membranes having substantially entirely of microfibers have a large surface area, e.g., up to 20 m2. 2 / g wider or 25m 2 / g and in some embodiments result in a material with a very good balance of strengths having a product of matrix tensile strengths in two perpendicular directions of at least 1.5x105 MPa2 and / or a matrix tensile strength ratio in two perpendicular directions of less than 4, possibly less than 1.5.

[0090] The expanded fluoropolymer membrane may be formed to have an appropriate thickness and weight to provide the desired leaflet performance. For example, and without limitation, the leaflet 140 comprises an expanded fluoropolymer membrane having a thickness of about 0.1 μm. The expanded fluoropolymer membrane has a thickness of about 1.15 g / m. 2 A membrane according to an embodiment of the invention may have a matrix tensile strength of about 411 MPa in the longitudinal direction and 315 MPa in the transverse direction.

[0091] Additional materials may be incorporated into the pores or within the membrane material or between the membrane layers to enhance desired properties of the leaflet. The composite materials described herein may be prepared to have an appropriate thickness and mass to provide the desired leaflet performance. The composite material in an embodiment may include a fluoropolymer membrane and may have a thickness of about 1.9 μm and a mass of about 4.1 g / m2 The mass per unit area may be

[0092] Expanded fluoropolymer membranes combined with elastomers to form composites provide elements of the present disclosure with the necessary performance attributes for use in a variety of high cycle flexing implantable applications, such as heart valve leaflets. For example, the addition of elastomers can improve fatigue performance of leaflets by eliminating or reducing stiffening observed in ePTFE-only materials. In addition, it can reduce the tendency of the material to develop permanent deformations, such as crinkling or creases, which can lead to reduced performance. In one embodiment, the elastomer occupies substantially all of the pore volume or space within the porous structure of the expanded fluoropolymer membrane. In another embodiment, the elastomer is present in substantially all of the pores of at least one fluoropolymer layer. Filling the pore volume with elastomer or having elastomer present in substantially all of the pores reduces the space available for undesirable incorporation of foreign matter into the composite. An example of such a foreign matter is calcium, which can be drawn into the membrane by contact with blood. If calcium is incorporated into composite materials used in heart valve leaflets, for example, mechanical damage can occur during the opening and closing cycle, leading to the formation of holes in the leaflets and poor hemodynamics.

[0093] In one embodiment, the elastomer combined with ePTFE is a thermoplastic copolymer of tetrafluoroethylene (TFE) and perfluoromethylvinylether (PMVE), as described in U.S. Patent No. 7,462,675 to Chang et al. As described above, the elastomer is combined with the expanded fluoropolymer membrane so that the elastomer occupies substantially all of the voids or pores in the expanded fluoropolymer membrane to form a composite material. This filling of the pores of the expanded fluoropolymer membrane with the elastomer can be achieved in various ways. In one embodiment, the method of filling the pores of the expanded fluoropolymer membrane includes dissolving the elastomer in a suitable solvent to prepare a solution with suitable viscosity and surface tension to flow partially or completely into the pores of the expanded fluoropolymer membrane, and evaporating the solvent to leave the filler.

[0094] In one embodiment, the composite material comprises three layers, two outer layers of ePTFE and an inner layer of fluoroelastomer disposed therebetween. Additional fluoroelastomers may be suitable and are described in U.S. Patent Application Publication No. 2004 / 0024448 to Chang.

[0095] In another embodiment, a method of filling the pores of an expanded fluoropolymer membrane includes delivering a filler via a dispersion to partially or completely fill the pores of the expanded fluoropolymer membrane.

[0096] In another embodiment, a method of filling the pores of an expanded fluoropolymer membrane comprises contacting a porous expanded fluoropolymer membrane with a sheet of elastomer under conditions of heat and / or pressure such that the elastomer flows into the pores of the expanded fluoropolymer membrane.

[0097] In another embodiment, a method of filling the pores of an expanded fluoropolymer membrane includes the steps of first filling the pores with a prepolymer of an elastomer and then at least partially curing the elastomer to polymerize the elastomer within the pores of the expanded fluoropolymer membrane.

[0098] Leaflets constructed from fluoropolymer materials or ePTFE generally perform better with higher elastomer percentages after a minimum weight percent of elastomer is reached, resulting in significantly increased cycle life. In one embodiment, the elastomer combined with ePTFE is a thermoplastic copolymer of tetrafluoroethylene and perfluoromethylvinylether as described in U.S. Patent No. 7,462,675 to Chang et al. and other references known to those skilled in the art. Other biocompatible polymers that may be suitable for use in the leaflet 140 include, but are not limited to, the following groups: urethanes, silicones (organopolysiloxanes), silicone-urethane copolymers, styrene / isobutylene copolymers, polyisobutylene, polyethylene-co-poly(vinyl acetate), polyester copolymers, nylon copolymers, fluorinated hydrocarbon polymers, and copolymers or mixtures of each of these.

[0099] Other considerations 10A and 10B are side exploded and assembled views, respectively, of a prosthetic valve 1000 according to another embodiment, comprising a generally tubular leaflet frame 1130 and a generally tubular outer frame 1120 connected by mechanical engagement members 1110. The leaflet frame 1130 includes engagement members 1110 that engage the outer frame 1120 to affect the connection, and the leaflet frame 1130 telescopes into the outer frame 1120. The leaflet frame 1130 defines a plurality of leaflet windows 137, and the film defines a leaflet extending from each leaflet window 137.

[0100] In certain embodiments, the valve 100 may be configured to not cover the crura of the left ventricle during implantation to prevent interference with the cardiac conduction system, as occurs with aortic valve replacement. For example, the valve 100 may have a length of less than about 25 mm, or less than about 18 mm. The valve 100 may also have an aspect ratio of less than 1, which describes the relationship between the length of the valve 100 and its functional diameter when expanded. However, the valve 100 may be constructed to any length, or more broadly, to any desired size.

[0101] In a transcatheter embodiment, in a collapsed state, the valve 100 may have a collapsed profile that is less than about 35% of its expanded profile. For example, a valve 100 with an expanded diameter of 26 mm may have a collapsed diameter of less than about 8 mm or less than about 6 mm. This percentage difference in diameter will depend on the dimensions and materials of the valve 100 and its various applications, and therefore the actual percentage difference is not limited to this disclosure.

[0102] Valve 100 may further include a bioactive agent that may be coated onto some or all of film 160 for sustained release of the agent once valve 100 is implanted. Bioactive agents may include, but are not limited to, vasodilators, anticoagulants, antiplatelet agents, and antithrombotic agents, such as, but not limited to, heparin. Other bioactive agents also include, but are not limited to, natural products such as vinca alkaloids (i.e., vinblastine, vincristine, and vinorelbine), paclitaxel, epidipodophyllotoxins (i.e., etoposide, teniposide), antibiotics (dactinomycin (actinomycin D), daunorubicin, doxorubicin, idarubicin), anthracyclines, mitoxantrone, bleomycin, plicamycin (mithramycin), and mitomycin, enzymes (L-asparaginase, which metabolizes L-asparagine systemically, nutrient-starving cells that cannot synthesize asparagine on their own); antiplatelet agents, such as G(GP)IIb / IIIa inhibitors and vitronectin receptor antagonists; antiproliferative / antimitotic alkylating agents, such as nitrogen mustards (mechlorethamine, cyclophosphatase, and the like). amides and analogs, melphalan, chlorambucil), ethylenimines and methylmelamines (hexamethylmelamine and thiotepa), alkyl-busulfan sulfonates, nitrosoureas (carmustine (BCNU) and analogs, streptozocin), trazene-decarbazinine (DTIC); antiproliferative / antimitotic antimetabolites such as folic acid analogs (methotrexate), pyrimidine analogs (fluorouracil, floxuridine and cytarabine), purine analogs and related inhibitors (mercaptopurine, thioguanine, pentostatin and 2-chlorodeoxyadenosine {cladribine}); platinum coordination complexes (cisplatin, carboplatin), procarbazine, hydroxyurea, mitotane, aminoglutethimide; hormones (i.e., estrogens); anticoagulants (heparin, synthetic heparin salts and other thrombin inhibitors);Fibrinolytics (e.g. tissue plasminogen activator, streptokinase and urokinase), aspirin, dipyridamole, ticlopidine, clopidogrel, abciximab; antimigratory drugs; antisecretory drugs (breveldin); anti-inflammatory drugs such as corticosteroids (cortisol, cortisone, fludrocortisone, prednisone, prednisolone, 6α-methylprednisolone, triamcinolone, betamethasone and dexamethasone), non-steroidal drugs (salicylic acid derivatives, i.e. aspirin; para-aminophenol derivatives, i.e. acetaminophen; indole and indene acetic acids (indomethacin, sulindac and etodalac), heteroaryl acetic acids (tolmetin, diclofenac and ketorolac), arylpropionic acids (ibuprofen and derivatives), anthranilic acids (mefenamic acid and meclofenamic acid), enolic acids (enolic acids) (piroxicam, tenoxicam, phenylbutazone and oxyphenthatrazone, nabumetone, gold compounds (auranofin, aurothioglucose, sodium gold thiomalate); immunosuppressants: (cyclosporine, tacrolimus (FK-506), sirolimus (rapamycin), azathioprine, mycophenolate mofetil); angiogenics: vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF); angiotensin receptor blockers; nitric oxide donors; antisense oligonucleotides and combinations thereof; cell cycle inhibitors, mTOR inhibitors and growth factor receptor signaling kinase inhibitors; retenoids; cyclin / CDK inhibitors; HMG coenzyme reductase inhibitors (statins) and protease inhibitors;

[0103] Transcatheter Delivery System In one embodiment, referring to FIG. 4A , a valve delivery system 500 includes a valve 100 having a collapsed configuration and an expanded configuration as described above, and an elongated flexible catheter 480, e.g., a balloon catheter, configured to deploy the valve 100 via intravascular access. The catheter 480 may include a balloon to expand the valve 100 and / or modify the valve 100 to properly seat as needed. The valve 100 may be attached to a distal portion of the catheter 480 for delivery through the vasculature. To hold the valve on the catheter 480 in the collapsed configuration, the valve delivery system may further include a detachable sheath (not shown) that fits snugly over the transcatheter valve 100.

[0104] The delivery method may include radially compressing the valve into its collapsed configuration onto a distal end of an elongated flexible catheter having a proximal end and a distal end, delivering the valve via a transfemoral or transapical route to a tissue opening, such as a native aortic valve opening, and expanding the valve into the tissue opening. The valve may be expanded by inflating a balloon.

[0105] The delivery method may include radially compressing the valve into its collapsed configuration onto a distal portion of an elongated flexible catheter having a proximal end and a distal end. A restraint is attached near the post of the valve, which may be connected to a tether that passes through the opening of the valve and the lumen of the catheter. The valve is then delivered to a native valve opening, such as a native aortic valve opening, via a native opening delivery and expansion route. The delivery route may include a transfemoral or transapical route. The valve may be expanded by inflating a balloon.

[0106] Manufacturing method The embodiments described herein also relate to methods of manufacturing the valve 100 embodiments described herein. To manufacture the various embodiments, a cylindrical mandrel 710 may be used. Referring to Figure 9A, the mandrel 710 includes a structural configuration capable of receiving the leaflet frame 130 and outer frame 120 thereon.

[0107] 9A and 9B, one embodiment of a method for manufacturing valve 100 includes wrapping a first layer of film 160, such as a composite material as described herein, in a tubular shape around mandrel 710; placing leaflet frame 130 and outer frame 120 over the first layer of film 160 as shown in FIG. 9A; forming a second layer of film 160 over leaflet frame 130 and outer frame 120; heat curing the assembly; cutting film 160 across the top of leaflet window 137 within leaflet window 137 and shaping leaflets 140 with release material 170. the leaflet frame 130 is secured to the outer frame 120 by a first pair of film 160 and a second pair of film 160 which are spaced apart from the leaflet frame 130 by a second pair of film 160; the leaflet frame 130 is secured to the outer frame 120 by a second pair of film 160 which are spaced apart from the leaflet frame 130 by a second pair of film 160; the leaflet frame 130 is secured to the outer frame 120 by a second pair of film 160;

[0108] Referring to Figure 12, the mandrel 710 is provided with a structural configuration capable of receiving the leaflet frame 130 thereon. One embodiment of a method of manufacturing the valve 100 includes the steps of tubularly winding a first layer of film 160, such as a composite material as described herein, around the mandrel 710; placing the leaflet frame 130 on the first layer of film 160 as shown in Figure 12; forming a second layer of film 160 on the leaflet frame 130; heat setting the assembly; receiving the assembly on a cutting mandrel 712 as shown in Figures 13A and 13B; and cutting the film 160 within the leaflet window 137 and across the top of the leaflet window to obtain the valve 100 of Figures 11A and 11B. Figures 11A and 11B depict the leaflets 140 on the cutting mandrel 712 in a partially open state. It can be seen that in a fully closed valve 100, under the influence of downstream fluid pressure, the free leaflet edges 142 of the leaflets 140 will come together and merge, thereby closing the valve and preventing downstream blood from flowing backward through the valve. EXAMPLES

[0109] Example 1 A heart valve was fabricated that was formed from a composite material having an expanded fluoropolymer membrane and an elastomeric material, with polymer leaflets bonded between two foldable metal frames.

[0110] The leaflet frame and outer frame were laser machined from lengths of hard-hardened SS316LVM tubing with an outer diameter of 23.0 mm, a wall thickness of 0.65 mm, and the shape roughly shown for illustration in Figure 9 A. The leaflet frame 130 and outer frame 120 were electropolished to remove 0.0127 mm of material from each face and to round the edges.

[0111] Fluorinated ethylene propylene (FEP) powder (Daikin America, Orangeburg, NY) was then applied to the leaflet frame 130 and the outer frame 120. More specifically, the FEP powder was stirred in an internal mixing device, such as a standard kitchen type blender, to create a suspended "cloud" and the frame was suspended in the cloud. The frame was exposed to the FEP powder cloud until a uniform layer of powder was deposited on all sides of the frame. The frame was then subjected to a heat treatment by placing it in a forced air oven set at 320°C for approximately 3 minutes. This melts the powder and deposits it as a thin coating over the entire frame. The frame was removed from the oven and allowed to cool to room temperature.

[0112] Initial Assembly and Heat Treatment Cycle The sintered ePTFE fiber was spirally wrapped around a 21 mm diameter vented cylindrical metal mandrel with a diameter corresponding to the inner diameter of the leaflet frame 130 and the outer frame 120. A thin film of Type 1 (ASTM D3368) FEP was made using melt extrusion and drawing. The Type 1 (ASTM D3368) FEP film was approximately 40 μm thick and approximately 7.7 cm wide. The mandrel was spirally wrapped with one layer of this Type 1 FEP film over the sintered ePTFE fiber in the area of ​​the outer frame only.

[0113] The mandrel was wrapped radially with five layers of ePTFE membrane, with the FEP coating facing the mandrel. The ePTFE membrane was manufactured according to the general teachings described in U.S. Pat. No. 7,306,729. The ePTFE membrane was 2.3 g / m 2 mass per unit area of ​​10.0 MPa, a bubble point of 101.5 MPa, a thickness of about 356 nm, and matrix tensile strengths of 319 MPa in the longitudinal direction and 407 MPa in the transverse direction.

[0114] The mandrel was spirally wrapped with one layer of Type 1 FEP film.

[0115] The leaflet frame and outer frame were expanded slightly in diameter and placed over the wrapped mandrel with approximately 10 mm of space between them. No rotational alignment was required.

[0116] The leaflet frame, outer frame and the space between them were spirally wrapped with one layer of Type 1 FEP film.

[0117] The leaflet frame, outer frame and the space therebetween which would become bridge section 162 and fold region 144 as shown in FIG. 2B were then circumferentially wrapped with five layers of ePTFE membrane having the same FEP coating as described above, with the coating facing the mandrel.

[0118] The wrapped leaflet frame, outer frame and the space between were encased in several layers of ePTFE membrane impregnated with a polyimide material referred to as a release liner.

[0119] A substantially non-porous ePTFE membrane was configured into a cylinder and placed over the assembly, referred to as the sacrificial tube, and both ends of the sacrificial tube were sealed to the mandrel using sintered ePTFE fibers.

[0120] The assembly, including the mandrel, was heated in a furnace where air pressure could be applied external to the sacrificial tube while a vacuum was maintained inside the mandrel for 40 minutes, resulting in a mandrel temperature of approximately 360° C. The assembly was removed from the furnace and allowed to cool to room temperature while still under pressure and vacuum.

[0121] The sacrificial tube and release liner were removed. The sintered ePTFE fiber was removed and the frame assembly was removed from the mandrel.

[0122] The polymeric material was trimmed and removed from the leaflet windows of the leaflet frames. The ends of each frame were trimmed circumferentially with a scalpel.

[0123] Intermediate Assembly and Heat Treatment Cycle An unsintered 15 mm diameter ePTFE tube was placed on a 21.5 mm diameter vented metal mandrel. Two layers of FEP coated substantially non-porous ePTFE membrane were wrapped circumferentially around the mandrel, coated side facing the mandrel. The wrapped mandrel was placed in a convection oven set at 320° C. and heated for 20 minutes. The combined ePTFE and substantially non-porous ePTFE membrane acted as a release liner and were perforated to provide pressure communication between the vents in the mandrel.

[0124] The leaflet frame was placed over a vented metal mandrel and vent holes were formed in the leaflet frame mesh above the mandrel vent holes.

[0125] The leaflet material was then prepared. An ePTFE membrane was manufactured according to the general teachings of U.S. Patent No. 7,306,729. The ePTFE membrane had a thickness of 0.452 g / m 2 The membrane had a mass per unit area of ​​about 100 nm, a thickness of about 508 nm, and a matrix tensile strength of 705 MPa in the longitudinal direction and 385 MPa in the transverse direction. The membrane was impregnated with a fluoroelastomer. The copolymer consisted essentially of about 65-70% by weight perfluoromethylvinylether and about 35-30% by weight tetrafluoroethylene complementary thereto.

[0126] The fluoroelastomer was dissolved in Novec HFE7500 (3M, St. Paul, MN) at a concentration of 2.5%. The solution was coated onto the ePTFE membrane (supported by a polypropylene release film) using a Mayer bar and dried in a convection oven set at 145° C. for 30 seconds. After the two coating steps, the final ePTFE / fluoroelastomer or composite had a mass of 1.75 g / m 2 %, 29.3% by weight fluoropolymer, a dome burst strength of about 8.6 KPa and a thickness of 0.81 μm.

[0127] The following test methods were used to characterize the ePTFE layers and multilayer composites. Thickness was measured using a Mutitoyo Snap Gauge Absolute, made in Japan, with a 0.50 inch (12.7 mm) diameter foot, model ID-C112E, serial number 10299. Density was determined using a Mettler analytical balance PM400 (NJ, USA) and weight / volume calculations. Break force and tensile strength were measured using an Instron model number 5500R (Norwood, MA) using flat jaws with a 50 kg load cell, gauge length = 25.4 cm, and crosshead speed = 25 mm / min (strain rate = 100% / min). Unless otherwise specified, these test methods were used to obtain the data for the examples that follow.

[0128] Ten layers of composite leaflet material were wrapped around the leaflet frame with the elastomer rich side of the composite facing the mandrel. In a preferred embodiment, the composite is stretched to have a predetermined matrix tensile strength along a direction generally perpendicular to the longitudinal axis of the mated tool assembly. More specifically, the predetermined matrix tensile strength is about 705 MPa.

[0129] The mandrel was radially wrapped with one layer of substantially non-porous ePTFE membrane, with the FEP coating facing the mandrel and spaced 8 mm from the base of the leaflet frame. The ePTFE membrane was manufactured according to the general teachings set forth in U.S. Pat. No. 7,306,729. The ePTFE membrane had a mass of approximately 11 g / m 2 mass per unit area, a thickness of about 5.5 μm, and matrix tensile strengths of 310 MPa in the longitudinal direction and 103 MPa in the transverse direction.

[0130] A Kapton® (EI DuPont de Nemours, Inc., Wilmington, Del.) polyimide film, which served as a mask, was wrapped over the substantially non-porous ePTFE membrane having the FEP coating layer.

[0131] The outer frame was placed on the mandrel with 10 mm separation between the leaflet frame and the outer frame. The leaflet frame and the outer frame were aligned so that the longitudinal outer frame posts were collinear with the leaflet frame posts.

[0132] The leaflet frame and outer frame were then wrapped with 24 layers of the composite leaflet material described above, with the elastomer rich side of the composite facing the mandrel. In a preferred embodiment, the composite material is stretched to have a predetermined matrix tensile strength along a direction generally perpendicular to the longitudinal axis of the combined tool assembly. More specifically, the predetermined matrix tensile strength is about 705 MPa.

[0133] The final leaflets contained 29.3 wt% fluoropolymer and were approximately 27 μm thick. Each leaflet had 34 layers of composite, giving a thickness / number of layers ratio of 0.8 μm.

[0134] The mandrel was again radially wrapped with one layer of substantially non-porous ePTFE membrane, with the FEP coating facing the mandrel, 8 mm away from the base of the leaflet frame.

[0135] The assembly was wrapped in several layers of a sacrificial release liner. A sacrificial tube was placed over the assembly and both ends of the sacrificial tube were sealed to the mandrel using sintered ePTFE fiber.

[0136] The assembly was processed in a furnace where air pressure could be applied from outside the sacrificial material configured in the tube while a vacuum was maintained inside the tube for 25 minutes, resulting in a mandrel temperature of approximately 330° C. The assembly was removed from the furnace and allowed to cool to room temperature while still under pressure and vacuum.

[0137] The sacrificial tube and liner were removed from the frame assembly and the frame assembly was removed from the mandrel. The Kapton® mask was removed.

[0138] A scalpel was used to trim circumferentially the free edge of each leaflet and the distal end of the leaflet frame.

[0139] Final Assembly and Heat Treatment Cycle The outer frame was radially expanded to a diameter of 24 mm using a tapered mandrel.

[0140] A release liner as described above was placed onto a 21.5 mm vented mandrel.

[0141] Three Kapton® masks were cut into a leaflet window shape with 30 mm tapered extensions.

[0142] The frame with the leaflet material was placed over the mandrel and the tapered extension of the Kapton® mask was inserted from the trimmed end under the top ring of the leaflet frame and advanced axially until the mask was flush with the leaflet window.

[0143] The leaflet frame was wrapped in two layers of Type 1 FEP film.

[0144] A hot iron was used to remove the FEP film from the leaflet window area by melting it away from the perimeter and tacking the FEP film onto the entire area of ​​the leaflet frame on the outside of the mask.

[0145] Vents were made in all of the frame meshes and in the polymer tubing areas connecting the inner and outer frames.

[0146] While holding the leaflet frame in place, the bridge portions of the adjacent tubes were flipped over in a telescopic fashion so that the outer frame was placed coaxially over the leaflet frame.

[0147] The entire frame assembly was then circumferentially wrapped with a sheet of substantially non-porous ePTFE membrane with the FEP coating facing the mandrel.

[0148] The assembly was wrapped in several layers of a sacrificial release liner. A sacrificial tube was placed over the assembly and both ends of the sacrificial tube were sealed to the mandrel using sintered ePTFE fiber.

[0149] The assembly was processed in a furnace where air pressure could be applied from outside the sacrificial material configured in the tube while a vacuum was maintained inside the tube for 25 minutes, resulting in a mandrel temperature of approximately 330° C. The assembly was removed from the furnace and allowed to cool to room temperature while still under pressure and vacuum.

[0150] The frame assembly was removed from the mandrel.

[0151] A scalpel was used to trim each end of the leaflet frame circumferentially.

[0152] The Kapton was peeled away from the inner side of the outer frame and the leaflets while rotating.

[0153] Using scissors, both ends of the leaflet frame were trimmed to follow the contours of the frame.

[0154] The resulting valve 100 includes leaflets 140 formed from a composite of two or more fluoropolymer layers having a plurality of pores and an elastomer present in substantially all of the pores of the two or more fluoropolymer layers. Each leaflet 140 is movable between a closed position, shown in Figure 3B, in which blood is substantially prevented from flowing through the valve assembly, and an open position, shown in Figure 3A, in which blood is permitted to flow through the valve assembly. Thus, the leaflets 140 of the valve 100 generally regulate the direction of blood flow in a human patient by switching between the closed and open positions.

[0155] Characterization of the valve leaflet performance was performed with a real-time pulsatile replicator measuring typical anatomical pressures and flows on both sides of the valve. Characterization of flow performance was performed using the following process:

[0156] The valve assembly was then fitted with a silicone annular ring (support structure) and subsequently evaluated in a real-time pulsatile replicator. Fitting was performed according to the instructions of the pulsatile replicator manufacturer (ViVitro Laboratories Inc., Victoria, BC, Canada).

[0157] The ring-mounted valve assembly was then placed into a real-time left heart pulsatile reproduction system, which contained the following components supplied by VSI ViVitro Systems Inc. (Victoria, BC, Canada): Super Pump, servo power amplifier part number SPA 3891; Super Pump Head, part number SPH 5891B, cylinder area 38.320 cm 2 ;valve station / fixture;wave generator, TriPack, part number TP 2001;sensor interface, part number VB 2004;sensor amplification components, part number AM 9991;square wave electromagnetic flowmeter (Carolina Medical Electronics Inc., East Bend, NC, USA).

[0158] Generally, blood flow pulsatile replication systems use a fixed displacement piston pump to generate the desired fluid flow through the valve under test.

[0159] The cardiac flow pulsatile system was adjusted to produce the desired flow (5 L / min), mean pressure (15 mmHg) and simulated rate (70 bpm). The valve under test was then cycled for approximately 5-20 minutes.

[0160] Pressure and flow data were measured and collected during the study, including right ventricular pressure, pulmonary artery pressure, flow rate, and pump piston position.

[0161] The parameters used to characterize the valve were the effective orifice area and the regurgitation rate. The effective orifice area (EOA) can be calculated as follows: EOA (cm 2 )=Qrms / (51.6*(ΔΡ)1 / 2). Qrms is the root mean square systolic / diastolic flow (cm 3 / sec) and ΔP is the mean systolic / diastolic pressure drop (mmHg).

[0162] Another measure of the hydrodynamic performance of a valve is the regurgitation rate, which is the amount of fluid or blood that regurgitates through the valve divided by the stroke volume.

[0163] Hydrodynamic performance measurements are EOA=2.06cm 2 , reflux rate = 8.2%.

[0164] Example 2 Another valve was constructed as described in Example 1, with the following differences:

[0165] Initial Assembly and Heat Treatment Cycle The leaflet frame and outer frame were expanded slightly in diameter and placed 16 mm apart on the wrapped mandrel. Once the leaflet frame and outer frame were formed they were rotated into alignment.

[0166] Final Assembly and Heat Treatment Cycle A scalpel was used to cut above the mechanical connection tabs, which deformed to connect the inner and outer frames.

[0167] The resulting valve 100 includes leaflets 140 formed from a composite of two or more fluoropolymer layers having a plurality of pores and an elastomer present in substantially all of the pores of the two or more fluoropolymer layers. Each leaflet 140 is movable between a closed position, shown in Figure 3B, in which blood is substantially prevented from flowing through the valve assembly, and an open position, shown in Figure 3A, in which blood is permitted to flow through the valve assembly. Thus, the leaflets 140 of the valve 100 generally regulate the direction of blood flow in a human patient by switching between the closed and open positions.

[0168] The hydrodynamic performance was measured. The performance value was EOA=2.3 cm 2 , reflux rate = 11.8%.

[0169] Numerous features and advantages, including various alternatives, have been described above, together with details of the structure and function of the device and / or method. This disclosure is for convenience of explanation only and is not intended to be comprehensive. It will be apparent to those skilled in the art that various modifications may be made, particularly with respect to the structure, materials, elements, components, shapes, sizes and arrangements of parts, including combinations within the principles of this disclosure, to the fullest extent indicated in the broad and general meaning of the terms as expressed in the appended claims. To the extent that these modifications do not depart from the spirit and scope of the appended claims, they are intended to be included within their scope.

Claims

1. An artificial valve, a frame including frame members defining a generally tubular shape and defining an open mesh pattern, the open mesh pattern including a plurality of windows and a plurality of circumferentially extending rows of mesh, each window having a first width and each stitch in the circumferentially extending rows of mesh having a second width, the first width being at least twice the second width, the first width and the second width defined in a circumferential direction; a plurality of leaflets formed from a single sheet of material, the plurality of leaflets extending from the frame; An artificial valve comprising:

2. 2. The prosthetic valve of claim 1, wherein the frame includes a first end and a second end, and the plurality of circumferentially extending rows of mesh are disposed between the plurality of windows and the first end of the frame.

3. The prosthetic valve of claim 2 , wherein the plurality of windows are disposed adjacent the second end of the frame, the second end of the frame defining an outflow side of the prosthetic valve.

4. 2. The prosthetic valve of claim 1, wherein the plurality of circumferentially extending rows of mesh include at least two rows of mesh extending continuously around the circumference of the frame, the at least two rows of mesh being disposed adjacent to one another at a first end of the frame that defines an inflow side of the prosthetic valve.

5. The prosthetic valve of claim 1 , wherein the frame member includes a plurality of axially extending posts spaced circumferentially about the frame.

6. The prosthetic valve of claim 5 , wherein each axially extending post defines a side shared by two adjacent windows of the plurality of windows.

7. The prosthetic valve of claim 6 , wherein each axially extending post is coupled to a mesh having the second width.

8. The prosthetic valve of claim 1 , wherein the plurality of leaflets comprises tissue.

9. The prosthetic valve of claim 1 , wherein each window is defined by two angled frame members that join to form a cusp of the window.

10. An artificial valve, a frame comprising frame members defining an open mesh pattern between a first end and a second end of the frame, the open mesh pattern comprising: a plurality of first meshes circumferentially spaced apart about the frame at locations between the first end and the second end; a plurality of second meshes arranged in a plurality of circumferentially extending mesh rows extending continuously around the frame; a frame, a first portion of the plurality of circumferentially extending rows being disposed between the first end of the frame and the plurality of first meshes, and a second portion of the plurality of circumferentially extending rows being disposed between a second end of the frame and the plurality of first meshes, each first mesh being wider than each second mesh, the width being defined in a circumferential direction; a plurality of leaflets extending from the frame; An artificial valve comprising:

11. The prosthetic valve of claim 10 , wherein the first portion of the plurality of circumferentially extending rows includes a single row of a second mesh.

12. The prosthetic valve of claim 10 , wherein the second portion of the plurality of circumferentially extending rows includes two or more rows of second meshes.

13. The prosthetic valve of claim 10 , wherein the first end of the frame defines an outflow side of the prosthetic valve and the second end of the frame defines an inflow side of the prosthetic valve.

14. 11. The prosthetic valve of claim 10, wherein a portion of the frame member at least partially defines the first and third meshes arranged in a plurality of circumferentially extending mesh rows that extend discontinuously around the frame.

15. The prosthetic valve of claim 10 , wherein the plurality of leaflets extend across the plurality of first meshwork inside the frame.

16. The prosthetic valve of claim 10 , wherein each second mesh of the plurality of second meshes is diamond-shaped.

17. An artificial valve, A frame including frame members defining an open mesh pattern, the open mesh pattern includes a circumferentially extending row of windows and a plurality of circumferentially extending rows of mesh, each window having a first width and each stitch in the circumferentially extending rows of mesh having a second width, the first width being at least twice the second width, and the first width and the second width being defined in a circumferential direction; a frame member including a plurality of axially extending posts spaced circumferentially about the frame, each post defining a side shared by two adjacent windows of the plurality of windows, a portion of the frame member defining a base of each window of the plurality of windows and a first circumferentially extending row of mesh extending continuously about the frame; a plurality of leaflets formed from a single sheet of material, the plurality of leaflets extending from the axially extending posts of the frame; An artificial valve comprising:

18. 18. The prosthetic valve of claim 17, wherein the frame comprises a first end defining an outflow side of the prosthetic valve and a second end defining an inflow side of the prosthetic valve, the plurality of circumferentially extending rows of mesh being disposed between the plurality of windows and the second end of the frame.

19. 20. The prosthetic valve of claim 18, wherein the row of circumferentially extending windows is disposed closer to the first end of the frame than to the second end.

20. 19. The prosthetic valve of claim 18, wherein the plurality of circumferentially extending mesh rows includes a second circumferentially extending mesh row extending continuously around the frame and adjacent to the first circumferentially extending mesh row, the first and second circumferentially extending mesh rows being disposed adjacent one another at the second end of the frame.

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