JP2010527745A - Prosthetic heart valve - Google Patents

Abstract

  The present invention includes a prosthetic heart valve having a flexible lobular portion and a method of manufacturing a heart valve that is improved over the prior art.

Description

Cross-reference of related applications

  This application claims the priority of US patent application Ser. No. 11 / 754,249, filed May 25, 2007 under the title of the invention “Prosthetic Heart Valve”, the disclosure thereof. Is incorporated by reference for all purposes.

  The present invention relates to a prosthetic heart valve having a flexible lobule portion made of tissue or synthetic material, and is also directed to an improved method of manufacturing such a valve.

  The human heart has four main valves that regulate the direction of blood flow in the circulation. The aortic and mitral valves are the “left” part of the heart and regulate oxygen-rich blood flow from the lungs to the body, while the pulmonary and tricuspid valves are the “right” part of the heart, Regulates the flow of hypoxic blood from the lungs to the lungs. The aortic valve and the mitral valve are located between the pumping chamber (ventricle) and the main artery and prevent blood from flowing back into the ventricle after it has been pumped into the circulation. The pulmonary and tricuspid valves are located between the receiving chamber (atrium) and the ventricle and prevent blood from flowing back into the ventricle during drainage.

 Heart valves may exhibit anatomical abnormalities as a result of congenital or acquired valve disease. Congenital heart valve abnormalities are well tolerated for many years, but eventually result in life-threatening problems in older patients or are very severe and the first in life Emergency surgery may be required within a few hours. Hypertension also causes heart valve abnormalities. Acquired valve diseases include degenerative processes (eg, Barlow disease (infant scurvy), elastic fiber deficiency), inflammatory processes (eg, rheumatic heart disease) and infectious processes (eg, endocarditis). Can be mentioned. In addition, ventricular damage from a previous heart attack (ie, myocardial infarction following coronary artery disease) or other heart diseases (eg, cardiomyopathy) can deform the shape of the valve and cause dysfunction.

Since heart valves have a passive structure that simply opens and closes in response to pressure differences on either side of a particular valve, there are two categories of problems that can arise with the valve: Can be classified into stenosis that does not open and (2) dysfunction that the valve does not close properly. Valve stenosis exists when the valve does not open completely, creating a relative obstruction in the bloodstream. Valve regurgitation exists when the valve does not close completely, resulting in blood regurgitation in the previous chamber. Stenosis and dysfunction can occur concomitantly with the same or different valves. Both of these conditions increase the work of the heart and become very serious. The severity of this increased stress in the heart and patient, and the matching heart function, determines whether it needs to be replaced surgically or in some cases needs to be repaired. . When left untreated, these medical conditions produce debilitating symptoms, including congestive heart failure, permanent heart failure, and eventual lethality.
A dysfunctional valve can be repaired while the patient's own valve is preserved, or it can be replaced with a mechanical or biological valve replacement. Because all heart valve prostheses have several disadvantages, such as the need for lifelong treatment with blood anticoagulants, the risk of thrombus formation, and limited endurance, When possible, valve repair is usually preferred over valve replacement. However, many dysfunctional valves are afflicted beyond repair.

 Since the left ventricle is the main pumping chamber of the heart, dysfunction of the left valve, the aortic valve and the mitral valve, is typically more severe. The aortic valve is more likely to constrict, which typically results in accumulation of calcifications on the valve leaflets, usually requiring replacement of the aortic valve. Refluxing aortic valves may be repairable but are usually replaced. The most common mitral valve pathology in modern society includes regurgitation due to the overall undulation of lobule, as well as ischemic disease, for relatively minor chordal lengthening . In many of these cases, the mitral leaflet is soft and flexible, and can be held for a long time in various repair means. However, in the Third World countries and central countries with a high proportion of immigrants from third world countries, the most common medical condition or disease is rheumatic mitral valve disease. This, often coupled with the fusion of two leaflets, results in a hypertrophic implied leaflet with striations or chords that are significantly deformed. Rheumatic valves are not suitable for either type of repair and are therefore almost always replaced.

 Because the right heart needs are much less than the left, the dysfunction that accompanies the pulmonary and tricuspid valves is fairly rare. The pulmonary valve has a structure and function similar to that of the aortic valve. Pulmonary valve dysfunction is often associated with complex congenital heart defects. Pulmonary valve replacement is sometimes performed in adults with many years of congenital heart disease. The anatomy and function of the tricuspid valve is similar to that of the mitral valve. The tricuspid valve also has annulus, striated tissue and papillary muscles, but has three leaflets (anterior, posterior, and septum). The shape of the annulus is slightly different, more snail shaped and slightly asymmetric.

 A prosthetic heart valve can be used to replace any heart valve. Two main types of prosthetic heart valves are known. One is a mechanical type heart valve that uses a pivoting mechanical closure, or a ball and cage design to provide unidirectional blood flow. The other is a “living” valve, made up of leaflets made of living tissue, which, for example, seal together, or join the seams of surrounding tissue known as seams, etc. It functions very much like the lobule of a natural human heart valve in that it mimics the natural action of. Another type of prosthetic valve has a structure similar to that of a biological valve, but its leaflets are made of a flexible synthetic material.

 Each type of prosthetic valve has its own advantages and disadvantages. Currently, mechanical valves have the longest durability of the available replacement heart valves. However, mechanical valve implantation must prescribe an anticoagulant to the recipient to prevent thrombus formation. Continuous use of anticoagulants can be dangerous because it greatly increases the risk of severe bleeding for the user. In addition, mechanical valves are often audible to the recipient and may fail without warning and can have serious consequences leading to death.

 In contrast, prosthetic valves with living leaflets and / or artificial leaflets are flexible and quiet, and those using living tissue leaflets do not require the use of blood anticoagulants. However, the processes that occur naturally in the human body include stresses on the valve, particularly the joint junctions between the leaflets of the valve and the attachment points of the surrounding leaflets, or the “tip” of the outer edge of each leaflet. In high areas, the leaflets may harden or calcify over time. Furthermore, the valve is subjected to stresses in the body resulting from certain mechanical movements. In particular, the leaflets are in a stretched state when in the closed position and in a compressed state when in the open position. Therefore, these types of prosthetic valves must wear and replace over time. Biological and artificial lobular heart valves are also much more difficult and time consuming to manufacture than mechanical heart valves because they are made by hand by highly trained experts.

 As a biological valve, a homologous valve including a valve extracted from a human organ donor or a cadaver; a homogeneous valve including a biological material supplied from a human cadaver; a self-transplant including a biological material supplied from an individual receiving the valve Valves; and heterologous valves that include biomaterials derived from non-human biological sources, including pigs, cows, or other animals.

 Currently available heterogeneous valves are available by sewing the leaflets of the porcine aortic valve to a wire frame / foam or stent (to hold the leaflets in place) or in cattle, horses, pigs or other animals Constructed by constructing valve leaflets from the pericardium (the membrane surrounding the heart) and stitching them to the wire frame / foam, in other words, connecting to a supporting stent or ring, which is often the pericardium It is called a valve. An example of a commercially available valve having the latter configuration is the Carpentier-Edwards Perimount ™ pericardial valve. The valve stent has an upper surface that “fits” the lower surface of the wire foam, with the leaflet edge sandwiched therebetween. In these types of heterogeneous valve embodiments, the wire frame / stent provides a dimensionally stable support structure that controls the degree of flexibility to reduce stress on the leaflet tissue during valve opening and closing. Built to provide valve leaflets. The wire frame / stent is covered with a biocompatible fabric (typically a polyester fiber material such as Dacron ™ or PTFE) that provides a stitched connection between the leaflet seam and the leaflets. Alternatively, the fabric covering the suture ring is attached to a wire frame or stent and provides a connection site for suturing the valve structure located within the patient's heart during surgical valve replacement. A number of prosthetic tissue valves having these configurations are disclosed in US Pat.

 While improvements have been made over the last 20 years, existing biological valves have drawbacks. One such drawback is a mismatch in size and mass between the facing surfaces of the wire foam and the stent. Misalignment is often due to variations in the shape of the stent ring. Prior art stents are manufactured from a length of material formed or bent into an annular structure, the ends of which are welded together. The forming and welding process results in a stent that is susceptible to "springback", i.e., slightly strained by the ring and over time, it no longer lacks the annular shape. The tension that is applied to the stent when it is sutured with the wire foam and experienced while the valve is functioning normally makes the stent more susceptible to springback. As shown in FIG. 1, the misalignment 2 exists between the annular wire form 4 and the stent ring 6 that lacks the annular shape. This misalignment 2 often results in a wire form 4 that is offset in either direction from the stent ring 6, in other words, instability between the components. This instability results in non-uniform stress points, especially in the leaflet of the valve, and promotes subsequent valve wear.

 Another disadvantage of the existing tissue valve configuration is the possibility of thrombus formation within the coating placed on the wire foam and stent ring. This is best illustrated in FIG. 2, which shows a cross-sectional side view of a seam portion in a prior art bioprosthesis when the seam is exposed to the natural forces provided by the leaflets in the closed position (wires). (The form is not shown). To reinforce the wire foam-stent assembly, the seam extensions or support members 8 are often incorporated into the valve at each seam. The support member 8 is an elongated protrusion extending upward from the stent ring 6 (in the direction of the outflow opening of the valve), and the space formed between the stent ring 6 and the wire foam (not shown) at the joint portion of the valve. Is substantially within the range. These seams are generally made of a relatively stiff but supple (bendable) material, such as the acetate material sold under the brand name MYLAR. In this way, the component is subjected to a radial inward force exerted on the valve leaflets and a tension exerted on the valve seam under natural operating conditions such as blood backflow pressure. May be slightly inwardly bent, deflected, or distorted. When this deflection occurs, a sac 7 can be formed between the fabric covering 5 and the support 8 of the seam, thereby forming a thrombus and interfering with blood flow and valve function.

US Pat. No. 4,106,129 US Pat. No. 4,501,030 U.S. Pat. No. 4,647,283 US Pat. No. 4,648,881 US Pat. No. 4,885,005 US Pat. No. 5,002,566 US Pat. No. 5,928,281 US Pat. No. 6,102,944 US Pat. No. 6,214,054 US Pat. No. 6,547,827 US Pat. No. 6,585,766 US Pat. No. 6,936,067 US Pat. No. 6,945,997 US Pat. No. 7,097,659 US Pat. No. 7,189,259 US Patent Application Publication No. 2003/0226208 US Patent Application Publication No. 2006/0009842

 Therefore, there is room for improving the performance and stability of the biological valve and improving the manufacturing technology of the valve. The present invention seeks to address the aforementioned drawbacks while maintaining desirable structural and functional characteristics and ensuring the functional life of the valve.

  The present invention includes prosthetic heart valves and methods for their manufacture. The intended prosthetic heart valve comprises a stent structure, wire foam, and flexible valve leaflets. The stent structure includes a ring-like substrate and a seam extension extending from the substrate in the direction of valve flow. The wire foam is operably coupled to the stent structure at its outflow end. The leaflets are formed from a flexible biocompatible material including biological tissue such as pericardial tissue and / or synthetic materials such as polyurethane, or combinations thereof.

 The subject valve incorporates various improvements to address and overcome the shortcomings of prior art biological valves. Some of these improvements address the problem of “misalignment” that can occur between the wire foam and the stent. For example, in one variation, the stent thickness dimension (ie, the outer and inner diameter dimensions of the stent) is greater than or equal to the wire foam diameter dimension. In other variations, the stent structure has an outflow surface having a dimension that is greater than the dimension of the inflow surface. In certain embodiments, the ratio of stent outflow dimension to stent inflow dimension can be 1: 1 to at least about 8: 5 or greater. In another variation, the outflow surface of the stent includes a recess in the leaflet portion for adjusting the diameter dimension of the wire foam. In yet another variation, the stent is formed in such a way that there is no seam in its structure and has a diameter shape that remains substantially constant under the normal function of the valve. Furthermore, the valve wire foam has a diameter shape that is substantially the same as that of the stent structure such that the wire foam and the stent structure are spaced apart from each other so that the spacing is normal for the valve. It remains constant under function.

Certain other improvements provided by the present invention address the problem of thrombus formation in the region of the coating placed on the valve wire foam and stent. In particular, the targeted improvement is the sac between the coating and the inner surface of the stent seam extension, particularly when the extension is tensioned inward by the force imposed on the valve under normal operating conditions. Minimize or prevent the formation of
In one variation of the prosthetic valve of the present invention, the stent structure has a seam extension aligned within the seam peak of the wire foam, where the extension is slightly angled inwardly. With the inner wall of the stent, a pre-fixed angle is defined, typically in the range of about 0 ° to about 10 °. In this way, the range of motion to which the extension of the seam is exposed is minimized, thereby minimizing the possibility of sac formation between the capsule and the stent wall. Angulation of the seam extension can be accomplished by connecting the separately formed seam extension to the stent substrate by mechanical means such as stitches, which can be flexible. Define the bond that has sex. Alternatively, the extension may be integrally formed within the stent at a pre-fixed angle or a predetermined angle. In either case, the softness of the joint between the stent seam and the stent substrate is such that the seam shrinks or bends inward when subjected to normal operating forces acting on the valve and its leaflets. enable. Furthermore, the coating is provided substantially integral with the inner surface to avoid the formation of a sac between the fabric material and the inner surface of the seam extension. This can be achieved by providing a suture between the two.

 The method of the present invention comprises the steps of manufacturing a prosthetic valve, wherein the stent structure is shaped to have a shape that at least partially matches the shape of the wire foam. Such a method further comprises forming a seam extension from a mold similar to that of a stent substrate to form a monolithic structure. Another valve manufacturing method of the present invention comprises the step of forming or providing the extension of the stent seam at an angle to the inner wall of the stent. In other embodiments, the extension of the seam is molded separately from the stent substrate and then provides a flexible bond between each seam extension and the stent substrate. And then it is combined there.

 Other features, objects and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings.

 The invention is best understood from the following detailed description when read in conjunction with the accompanying drawings. It is noted that, according to common practice, the various features of the drawings are not to scale. In other words, the dimensions of the various features are scaled up or down for clarity. Also, for the purpose of clarity, certain features of the invention may not be depicted in some drawings. The following shapes are included in the drawing:

1 is a schematic view of the top surface of a prior art biological valve. The solid line represents the wire form and the broken line represents the stent structure. FIG. 4 is a side cross-sectional view of the extension of a prior art prosthetic valve joint at the joint. 1 is a side view of an assembled wire foam and stent structure of an artificial valve of the present invention. FIG. 3B is a cross-sectional view of the valve assembly of FIG. 3A taken along line BB of FIG. 3A. FIG. 3B is an enlarged end view of a cross section of the valve assembly defined by circle C in FIG. 3B. 3D is an enlarged cross-sectional view of the valve assembly along line DD in FIG. 3B. FIG. The sectional side view of the base material of the leaflet part of the valve assembly of this invention.

  The present invention will be described in further detail with respect to FIGS. 3A-3D and 4 and by the following description of exemplary embodiments and variations of the novel apparatus, systems and methods. The present invention generally includes an implantable prosthetic heart valve 10 having an annulus stent in the form of a ring 12 and an annulus wire form or frame 14, wherein the stent and wire form have substantially similar diameters. Have The wire form has an alternating pattern of arcuate leaflets 14a and upstanding seams 14b, so that it most closely matches the structure and function of a natural heart valve, such as an aortic valve, for replacement purposes. Each number typically comprises three (however, the three leaflet of the present invention is also suitable for replacing a bicuspid valve such as a mitral valve). This undulation pattern mimics the natural contour of leaflet connection and serves to support an artificial leaflet (not shown) within the valve. The stent 12 is aligned with the leaflets 14a and seams 14b of the corresponding wire foam 14 when the stent and wire foam are operatively coupled (open or open seam tips). And a closely matched pattern of leaflet portion 12a and seam 12b. The distal end of the valve 10 with the seam components 12b, 14b defines the outflow end of the valve and the opposite end defines the inflow end.

  As with many conventional prosthetic tissue valves, a tissue leaflet subassembly (not shown) is covered with a fabric material 42 (see FIG. 4) before the wire foam 14 is effectively connected to the stent 12. First fit, attach and secure to the existing wire form 14. The integrated tissue-wire foam structure is then secured to the stent structure 12 with the leaflet tissue edge 44 sandwiched therebetween to form the assembled valve 10. As shown in FIG. 4, the ring 12 is also covered with a cloth material 42 separately. A portion of the fabric material, along with both the stent and wire foam, extends radially outward from the component and each provides a means for stitching 46 the two components together 46a. And 42b are formed. When operatively coupled together, the wire foam 14 is attached to the upper side of the stent 12, thereby aligning and following the wire foam with the upper surface or outflow surface 34 of the stent 12. In a fully assembled valve with an integrated leaflet subassembly, the gap or spacing 20 defined between the two components has a leaflet tissue edge 44 over the entire length of the gap 20. Buried. As described above, the valve can be configured to be secured directly to the natural annulus, or otherwise attached to a suture ring (not shown) that is a natural annulus.

 The various techniques and materials used to form the leaflets that form / bend the wire form 14, manufacture the stent 12, attach and connect the various components, many of which are incorporated herein by reference. However, these are well known and understood by those skilled in the art. For example, tissue leaflets can be cut from excised tissue such as bovine pericardium. The fabric material used to cover the wire foam and stent can be DACRON ™ or another suitable fiber material. The wire form 14 can be made of a cobalt-nickel alloy wire (made by Elgiloy Ltd.), commonly used for such wire forms, and the stent 12 can be a machined metal or machined or molded. Manufactured plastic material (eg, DELRIN ™).

 The advantage of the present invention using a molded stent ring is that the stent structure has no seams (unlike the joints that are inevitably formed when welding the stent) and the stent shape is more accurately shaped as desired. Can be molded and therefore more accurately match the shape of the wire foam. In this way, a heavier and heavier stent component, with each shape very closely matched, is provided to the valve during the valve manufacturing process, for example when the stent and wire foam are sutured. Does not deform weaker and lighter wire foam when exposed to force. For example, without such an intimate fit, if the suture applied between the two component fabric coatings is too stiff or not stiff enough, the wire foam may There is a tendency to uncentered (see FIG. 4 which shows a wire form that is uniformly centered with respect to the outflow surface of the ring). This component fit ensures that the wire foam and the stent still maintain a uniform space with respect to each other, i.e. the spacing between them is constant for the entire valve and is thereby placed between them. Distribute the compressive force on the tissue evenly. The force evenly distributed over the valve is intended to minimize the risk of depletion of the immature valve as a whole and especially on leaflet tissue.

 Another feature of the present invention that helps to maintain proper alignment and centering of the wire foam with respect to the outflow end surface of the stent, independently or in combination with the closely matched shape of the stent and wire foam components, is: The relative thickness of the outflow surface 34 of the stent relative to the diameter of the wire foam. Typically, a conventional biological valve has a wire form with a diameter of about 0.508 mm to about 0.762 mm (about 0.020 "to about 0.030") and a stent thickness of about 0. .381 mm (about 0.015 "). These relative magnitudes are the natural force imparted on the valve by the blood flow and the tension imparted by the sutures formed to secure the wire foam to the stent. The wire foam tends to protrude above the outflow surface 34 of the stent, which can occur on either the inner surface 30 of the stent or the outer surface 32 of the stent. To address this problem, the targeted valve stent has an outflow stent surface 34 having a thickness that is equal to or greater than the diameter of the wire foam. May have a thickness in the range of 0.508 mm to about 2.54 mm (about 0.020 ″ to about 0.1 ″). In this way a “shoulder” is provided on the stent surface; Any deviation or movement of the wire foam thereon is adjusted to make it easier to achieve and maintain the centering of the wire foam on the stent surface.

 Another optional feature of the subject valve stent is to provide a recess or groove 38 in the outflow surface 34 of the leaflet portion of the stent, as shown in FIG. 3C. The recess has any suitable cross-sectional shape, such as a wedge shape, a circular shape, and has dimensions such as a radius of curvature sufficient to adjust the diameter of the wire (or the radius of the wire with the cloth coating), for example. sell.

 One skilled in the art will recognize that it is desirable to maintain the valve opening as wide as possible without including the function and stability of the valve. In this way, and also taking into account the positioning on the valve annulus of the present invention relative to the natural annulus, the valve of interest provides a thicker stent outflow surface while blood passing through the valve. Maintain a wide flow path. This is accomplished by selecting a stent cross-sectional shape that tapers from the outflow surface 34 to the inflow surface 36, ie, the stent outflow surface 34 is larger than the corresponding stent inflow surface 36. In the embodiment shown in FIG. 3C, the outflow surface 34 is thicker or larger than the inflow surface 36. In certain variations, the ratio of the outflow surface to the inflow surface can be from about 1: 1 to at least about 8: 5, but can be larger or smaller depending on the application. In one embodiment, the outflow surface has a size or thickness of about 1.016 mm (about 0.040 ″) and the inflow surface has a size or thickness of about 0.635 mm (about 0.025 ″). Have.

 In addition to the relative sizing of the outflow surface and the inflow surface of the stent, the particular shape of the stent cross-section can be designed to enhance flow dynamics. For example, the cross-sectional shape of the stent ring of FIG. 3C is a somewhat trapezoidal shape having an inner surface 30 that is substantially parallel to the direction of flow, while one outer surface 32 is angled toward the outer side to provide a natural valve. Define a ledge or step that extends toward the ring. Thus, the added thickness of the outflow surface 34 is adjusted without reducing the effective opening area. Although the illustrated embodiment shows an angled outer surface 32, a straight surface having other adjustable features integrated into the valve structure may be used.

 Stent 12 has a seam support member, or extension, or column 12b, each extending from a point of joinder having the stent substrate, where ring 12 is a wire form. 14 are operatively coupled to each seam portion of the wire form. Instead of being coplanar with and located in the base portion 12a of the stent in the existing biological valve structure, the extension 12b of the seam is bent slightly inwardly and has an inner wall 30 of the stent. Defines a fixed or predetermined angle α in the range of about 0 ° to about 10 ° (see FIG. 3D). Defined as the angle β when the extension member 12b is exposed to the natural force imparted on the valve leaflet by the flexibility of the material forming the support member 12b and the support member being compatible with the base portion of the ring 12 Provide a support member or bendable within a limited range of motion. The angle β is typically about 0 ° to about 45 °, and usually ranges from about 2 ° to about 5 °. In this way, the stress applied on the support member 12b is minimized. In one variation, the seam extension 12b may be a separately formed piece that is respectively coupled to the substrate 12 at a designated seam location. Extension may be coupled to the stent by stitching or other suitable means to define a flexible joint 48. Alternatively, the entire stent may be integrally molded with a predetermined angle α between the substrate 12a and the extension 12b, allowing the leaflet to bend within the angle range β when exposed to tension. Hinges may be provided. Optionally, suturing through or against the two to prevent thrombus formation that may occur between the inner surface 38 of the extension 12b and the fabric coating 38 during inward bending of the extension. 40 may be applied to maintain a substantially coplanar fabric coating with the inner surface 38. Alternatively, the fabric may be attached or secured to the inner surface of the extension by any other suitable means such as ultrasonic bonding.

 Methods relating to the subject valve device are also intended to be within the scope of the present invention. Methods of interest include, but are not limited to, stent ring molding and / or machining, wire foam bending, valve leaflet formation by bonding tissue to wire foam, wire foam and stent suturing, etc. Manufacturing and / or assembly processes or activities. Other methods relate to the use and implantation of valves in the body or provide potential steps and / or activities.

 Yet another aspect of the invention includes a kit having at least one valve of the invention. The kit may include various other components for valve preparation, delivery, implantation and fixation. The subject kit may also include instructions for implantation of the device. These instructions can be printed on a material such as paper or plastic. In this way, the instructions may be present in the kit as a package insert on the label of the container of the kit or its components, or stored on a suitable computer readable storage medium such as a CD-ROM, USB, etc. The electronic data file may be provided.

 The foregoing merely illustrates the principles of the invention. Those skilled in the art will recognize that although not explicitly described or shown herein, various arrangements may be devised that embody the principles of the invention and fall within its spirit and scope. I will. Furthermore, all examples and conditional languages cited herein are primarily intended to help readers understand the principles of the present invention and the concepts we have contributed to promote this technical field. It is intended to assist and should not be construed as being limited to such specifically cited examples and conditions. Also, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass their structural and mechanical equivalents. . In addition, such equivalents include both currently known and future developed equivalents, i.e., any element developed will perform the same function regardless of structure. Accordingly, the scope of the invention is not intended to be limited to the exemplary embodiments shown and described herein. Rather, the scope and spirit of the invention is embodied by the appended claims.

 As used in this specification and the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise. Please keep in mind. Thus, for example, reference to “a (single) yarn” includes a plurality of such yarns, and a reference to “cylindrical member” is known to one or more cylindrical members and those skilled in the art, and the like. Including their equivalents.

 If a range of numbers is provided, each intervening value between the upper and lower limits of the range, up to one-tenth of the lower limit, unless the context clearly indicates otherwise ) Is also understood to be specifically disclosed. Each of the smaller ranges between any stated numerical value or numerical value intervening in the stated range and any other numerical value or numerical value intervening in the stated range is encompassed by the invention. The The upper and / or lower limits of these smaller ranges may independently be included or excluded from the range, either one or both of the limiting values are included in the smaller range, Each range in the case where none is included is affected by the limit value specifically excluded in the described range. Where the stated range includes one or both of the limiting values, either or both of those included limiting values are also included in the invention.

 All publications mentioned in this specification are herein incorporated by reference to disclose and explain the methods and / or materials to which the publication is cited. The publications mentioned in this specification are provided solely for their disclosure prior to the filing date of the present application. The present invention should not be construed as an admission prior to such publications because of the prior invention. In addition, the date of publication provided may be different from the actual publication date and may need to be verified with other information.

Claims (15)

A stent having a thickness dimension;
A wire foam having a diameter dimension;
A prosthetic heart valve with
The thickness dimension is equal to or greater than the diameter dimension;
Artificial heart valve.  The thickness dimension ranges from about 0.508 mm to about 2.54 mm (about 0.020 "to about 0.1"), and the diameter dimension ranges from about 0.508 mm to about 0.762 mm (about 0.020 mm). The prosthetic heart valve according to claim 1, wherein the prosthetic heart valve is in the range "" to about 0.030 "). The wire foam has an alternating pattern of leaflets and seams;
The stent has an inflow surface and an outflow surface;
The outflow surface has an alternating pattern of leaflet and joint extension;
The prosthetic heart valve according to claim 1, wherein each extension of the seam of the stent is in a space defined by the seam of the wire foam.  The prosthetic heart valve of claim 1, wherein the stent includes a substrate made of DELRIN and an extension made of MYLAR. A wire foam having a diameter dimension;
In order to adjust the diameter dimension of the wire foam, a stent having an outflow surface and a recess inside thereof,
Including prosthetic heart valve.  6. The artificial heart valve according to claim 5, wherein the recess has a rounded shape.  6. The artificial heart valve according to claim 5, wherein the recess has a wedge-shaped structure.  6. The prosthetic heart valve of claim 5, wherein the stent comprises a substrate made of DELRIN and an extension made of MYLAR. An artificial heart valve,
A stent having a structure including a ring and a plurality of extensions extending from the ring;
At least the ring has a seamless structure and has a diameter shape that remains substantially constant under normal functioning of the valve when implanted.
Artificial heart valve.   10. The prosthetic heart valve of claim 9, wherein the ring is made of DELRIN and the plurality of extensions are made of MYLAR. Further comprising a wire foam having substantially the same shape as that of the stent structure;
The wire foam and stent structure are present at a fixed distance from each other;
The prosthetic heart valve according to claim 9, wherein the distance interval remains substantially constant under normal function of the valve when implanted. A method for producing a prosthetic valve comprising a stent and a wire foam,
The stent has an inflow surface and an outflow surface;
The wire foam is disposed on the outflow surface of the stent;
The method includes molding or machining the stent;
The method wherein the outflow surface of the stent has a shape that substantially matches that of the wire foam. Including a stent structure having an outflow surface and an inflow surface;
The outflow surface has a size larger than the size of the inflow surface,
Artificial heart valve.  14. The prosthetic heart valve of claim 13, wherein the ratio of the outflow surface dimension to the inflow surface dimension ranges from about 1: 1 to at least about 8: 5.  The artificial heart of claim 13, wherein the outflow surface dimension is about 0.040 "and the inflow surface dimension is about 0.025". valve.

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