Heart valve prosthesis and method of making the same

Abstract

The application provides a heart valve prosthesis and a preparation method thereof, the heart valve prosthesis comprising a stent and an integrated valve, the integrated valve comprising artificial valve leaves and a skirt, and the integrated valve being fixed to the stent by sewing threads; the preparation method comprises the following steps: obtaining an integrated valve material, and sequentially subjecting the integrated valve material to cutting, pre-shaping and folding processes, and finally sewing the folded integrated valve material on the stent to obtain the heart valve prosthesis. The application can minimize the damage to the valve, increase the durability of the valve, simplify the sewing process, reduce the production cost and improve the production efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of medical devices, in particular to a heart valve prosthesis and a preparation method thereof. BACKGROUND

[0002] The heart contains four chambers, the left atrium and left ventricle are located on the left side of the heart, and the right atrium and right ventricle are located on the right side of the heart. The atrium and ventricle form an atrioventricular inflow tract, the left ventricle and the aorta form a left ventricular outflow tract, and the right ventricle and the pulmonary artery form a right ventricular outflow tract. There are valves with "one-way valve" function at the atrioventricular inflow tract and the left ventricular outflow tract, which ensure the normal flow of blood in the heart chamber. When the valve is problematic, the cardiac hemodynamics changes, and the heart function is abnormal, which is called valvular heart disease.

[0003] With the development of social economy and the aging of the population, the incidence of valvular heart disease has increased significantly, and research shows that the incidence of valvular heart disease in the elderly population over 75 years old is as high as 13.3%. At present, the traditional surgical treatment is still the preferred treatment for patients with severe valvular disease, but for the elderly, patients with multiple organ diseases, patients with a history of thoracotomy, and patients with poor heart function, the risk of traditional surgical treatment is high, and the mortality rate is high. Part of the patients do not even have the opportunity to operate. Transcatheter valve replacement / repair surgery has the advantages of no need for thoracotomy, small trauma, and rapid recovery of patients, and has received widespread attention. In recent years, artificial valve technology has developed rapidly, but there are still some problems to be solved, mainly including insufficient durability of the valve, complex production and preparation process, high production cost, and low production efficiency.

[0004] It should be noted that the information disclosed in the background section of the present application is only intended to deepen the understanding of the general background of the present application, and should not be regarded as acknowledging or implying in any form that the information constitutes prior art known to those skilled in the art. SUMMARY

[0005] The purpose of the present application is to provide a heart valve prosthesis and a preparation method thereof, in order to solve the problems of insufficient durability, complex production and preparation process, and high production cost of the artificial heart valve in the prior art.

[0006] To achieve the above-mentioned purpose, the present application provides a heart valve prosthesis, comprising a stent and an integrated valve, the integrated valve comprising an artificial valve leaflet and a skirt, the integrated valve being fixed by suturing with the stent through a suture.

[0007] In one embodiment, the length of the artificial valve leaflet in the outflow tract portion is greater than the length in the inflow tract portion.

[0008] In one of the embodiments, the length of the skirt in the outflow portion is greater than or equal to the length in the inflow portion, so that the skirt can better fit the stent or the tissue.

[0009] In one of the embodiments, the skirt comprises an inner skirt and an outer skirt, the inner skirt is arranged at the inner side of the stent, and the outer skirt is folded at the outer side of the stent; the length of the inner skirt in the outflow portion is greater than or equal to the length in the inflow portion; and / or, the length of the outer skirt in the outflow portion is greater than or equal to the length in the inflow portion.

[0010] In one of the embodiments, the length of the artificial valve leaflet when unfolded is greater than the inner circumference of the stent.

[0011] In one of the embodiments, the length of the inner skirt when unfolded is less than or equal to the inner circumference of the stent, and the length of the outer skirt when unfolded is greater than the outer circumference of the stent.

[0012] In one of the embodiments, the skirt comprises an inner skirt and an outer skirt, the inner skirt is arranged at the inner side of the stent, and the outer skirt is folded at the outer side of the stent; the integrated valve at least meets one of the following conditions:

[0013] The height of the outer skirt is greater than the height of the inner skirt;

[0014] The ratio of the height of the artificial valve leaflet to the length of the inner skirt when unfolded is 0.15-0.3;

[0015] The ratio of the ear height of the artificial valve leaflet to the length of the inner skirt when unfolded is 0.01-0.05.

[0016] In one of the embodiments, each valve of the artificial valve leaflet comprises a valve leaflet free edge portion, an ear, a valve leaflet fixed portion, and a valve leaflet transition portion, the ear is arranged between the two ends of the valve leaflet free edge portion and the two ends of the valve leaflet fixed portion, the valve leaflet transition portion is arranged between the valve leaflet fixed portion and the skirt, the number of sewing stitches of the valve leaflet fixed portion is 3, the number of sewing stitches of the ear is 2, the number of sewing stitches of the skirt in the circumferential direction of the stent is 3-4, and the number of sewing stitches of the sewing edge of the artificial valve leaflet and the skirt in the axial direction of the stent is 2.

[0017] To achieve the above-mentioned purpose, the application further provides a preparation method of a heart valve prosthesis, which is used for preparing any one of the heart valve prostheses, and the preparation method comprises:

[0018] The integrated valve material is obtained, and the integrated valve material is sequentially subjected to cutting, pre-shaping and folding processes, and finally the folded integrated valve material is sewn on a stent to obtain a heart valve prosthesis.

[0019] In one of the embodiments, the pre-shaping process comprises:

[0020] The cutting integrated valve material is pre-shaped by using a shaping tool, and the shaping tool comprises a shaping mold and a gravity block.

[0021] During the pre-shaping process, the cutting integrated valve material is placed on the shaping mold, and the integrated valve material placed on the shaping mold is subjected to a circumferential tension by using the gravity block, and the integrated valve material is tensioned, and the valve material is pre-shaped under a predetermined condition.

[0022] In one of the embodiments, the valve material is pre-shaped in a treatment chamber containing a cross-linking agent, or the valve material is pre-shaped in a treatment chamber with a certain temperature, humidity and treatment time.

[0023] In one of the embodiments, the cross-linking agent is glutaraldehyde or genipin.

[0024] In one of the embodiments, the temperature is 60-120℃, the humidity is 10-80%, and the treatment time is 1-6 hours.

[0025] In one of the embodiments, the folding process comprises: placing the pre-shaped integrated valve material in a mold core to fold the pre-shaped integrated valve material into a three-dimensional shape by the mold core.

[0026] In summary, the heart valve prosthesis provided by the application comprises: a stent and an integrated valve, the integrated valve comprises artificial valve leaflets and a skirt, and the integrated valve is fixedly sewn with the stent by a sewing thread. In this way, the use of the integrated valve can minimize the damage to the valve, increase the durability of the valve, simplify the sewing process, reduce the production cost, and improve the production efficiency.

[0027] Since the preparation method of the heart valve prosthesis provided by the application belongs to the same inventive concept as the heart valve prosthesis provided by the application, the preparation method of the heart valve prosthesis provided by the application has all the advantages of the heart valve prosthesis provided by the application, and therefore the beneficial effects of the preparation method of the heart valve prosthesis provided by the application will not be described one by one. BRIEF DESCRIPTION OF DRAWINGS

[0028] Those skilled in the art will understand that the drawings provided herein are for illustrative purposes and constitute any limitation to the scope of the present application. Among them:

[0029] Figure 1 is a simplified structural schematic diagram of a heart valve prosthesis of an embodiment of the present application;

[0030] Figure 2a is a simplified structural schematic diagram of an integrated valve when it is deployed;

[0031] Figure 2b is a front view structural schematic diagram of a heart valve prosthesis of an embodiment of the present application;

[0032] Figure 2c is a perspective structural schematic diagram of a heart valve prosthesis of an embodiment of the present application;

[0033] Figure 3 is a partial schematic diagram of the relative suturing of the leaflet sewing edges of an embodiment of the present application;

[0034] Figure 4 is a schematic diagram of the sewing stitches of an integrated valve when it is deployed in an embodiment of the present application;

[0035] Figure 5 is a scenario diagram in which the heart valve prosthesis of an embodiment of the present application can reduce regurgitation when an integrated valve is used, and the arrows in the diagram represent the blood flow of regurgitation;

[0036] Figure 6a is a flowchart of the preparation of a heart valve prosthesis in an embodiment of the present application;

[0037] Figure 6b is a flowchart of the preparation of a heart valve prosthesis in another embodiment of the present application;

[0038] Figure 7a is a simplified structural schematic diagram of a sizing tool of an embodiment of the present application;

[0039] Figure 7b is a top view of a sizing tool of an embodiment of the present application;

[0040] Figure 8a is a structural schematic diagram of a sizing mold loaded with pericardial tissue of an embodiment of the present application;

[0041] Figure 8b is a structural schematic diagram of a female mold of an embodiment of the present application;

[0042] Figure 9 is a force schematic diagram of an artificial valve leaflet of an embodiment of the present application;

[0043] Figure 10a is a structural schematic diagram of a mold core in a first perspective of an embodiment of the present application;

[0044] Figure 10b Figure 6 is a structural schematic diagram of the mold core of the embodiment of the present application at a second perspective view.

[0045] In the drawings:

[0046] 10 - integrated valve material; 100 - heart valve prosthesis; 110 - stent; 111 - stent strut; 120 - integrated valve; 121 - artificial valve leaflet; 1211 - free edge portion of valve leaflet; 1212 - ear; 1213 - fixed portion of valve leaflet; 1214 - transition portion of valve leaflet; 1215 - sewn edge of valve leaflet; 122 - inner skirt; 1221 - sewn edge of inner skirt; 1222 - first side of inner skirt edge; 123 - outer skirt; 1231 - sewn edge of outer skirt; 1232 - second side of outer skirt edge; 130 - suture; 200 - sizing tool; 210 - holding container; 220 - support seat; 230 - sizing mold; 2310 - female mold; 2311 - concave surface; 2320 - male mold; 2321 - convex surface; 240 - gravity block; 300 - mold core; L1 - length of artificial valve leaflet when unfolded, i.e. length of outflow portion of artificial valve leaflet; L2 - length of inner skirt when unfolded, i.e. length of inflow portion of artificial valve leaflet, inner skirt or outer skirt; L3 - length of outer skirt when unfolded, i.e. length of outflow portion of outer skirt; H1 - ear height of artificial valve leaflet; H2 - height of artificial valve leaflet; H3 - height of inner skirt; H4 - height of outer skirt; A - inflow; B - outflow; F1 - circumferential force on valve leaflet; F2 - radial force on valve leaflet. DETAILED DESCRIPTION

[0047] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0048] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0049] In the description of the present application, it is necessary to point out that, unless otherwise explicitly specified and limited, the terms "mount", "connect", "connection" should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integrally connected; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0050] "Circumferential" as described herein refers to a direction around the stent central axis, "axial" refers to a direction parallel to the stent central axis. "Inflow tract" as described herein corresponds to the position of blood flow into the prosthesis when the heart valve prosthesis is operated, and "outflow tract" corresponds to the position of blood flow out of the prosthesis when the heart valve prosthesis is operated.

[0051] The core of the present application is to provide a heart valve prosthesis and a preparation method thereof, to solve the problems of insufficient durability, complex production process, high production cost, low production efficiency and the like of the prior art heart valve prosthesis.

[0052] The following is described with reference to the accompanying drawings. In the case of no conflict, the embodiments and features in the embodiments described below can be supplemented or combined with each other.

[0053] As shown in Figure 1 The embodiment of the present application provides a heart valve prosthesis 100 which can be implanted in the heart to replace the native valve, such as to replace the mitral valve, tricuspid valve, aortic valve or pulmonary valve, to enable one-way blood flow, and basically has the function of a natural heart valve. The heart valve prosthesis 100 specifically comprises a stent 110, an integrated valve 120 and a suture 130. The integrated valve 120 is sutured and fixed with the stent 110 by the suture 130.

[0054] The stent 110 can provide several functions for the heart valve prosthesis 100, including serving as the main structure of the valve, bearing the integrated valve 120 for support, connecting structure (hanging ear or fixed ear) with the delivery system, etc. The stent 110 is a tubular structure, having a contracted state for delivery and an expanded state for deployment. The stent 110 can be woven or cut. The stent 110 can be made of a metal material such as nickel-titanium, titanium alloy, cobalt-chromium alloy, MP35n, 316 stainless steel, or a biocompatible metal frame made of other biocompatible metals known to those skilled in the art or a laser-cut solid metal tube, preferably nickel-titanium alloy. The stent 110 can also be selected from materials that can be elastically or plastically deformed, such as balloon-expandable materials.

[0055] As shown in Figures 2a to 2cAs shown, depending on their function, the integrated valve 120 can be divided into an artificial leaflet 121, an inner skirt 122, and an outer skirt 123 connected in sequence. The outer skirt 123 is an optional structure. It should be noted that the integrated valve 120 means that the artificial leaflet 121 and the skirt are manufactured as a single piece or integrally molded. In this invention, the integrated valve 120 minimizes damage to the valve, increases valve durability, simplifies the suturing process, reduces production costs, and improves production efficiency. Furthermore, as... Figure 5 As shown, when the integrated valve 120 closes, the number of sutures is reduced, and regurgitation is less likely to occur (the arrow indicates the direction of regurgitated blood flow), resulting in better tightness and better performance.

[0056] In the illustrated embodiment, the artificial leaflet 121 is a three-lobed type, with an open state and a closed state, and can dynamically switch between the open and closed states. When the artificial leaflet 121 is in the closed state, the free edge 1211 of the artificial leaflet 121 (see...) Figure 2a The artificial leaflets 121 are closed or joined together in a sealing manner. When the artificial leaflets 121 are in the open state, the free edges 1211 of the artificial leaflets 121 are opened in a way that they are far apart from each other.

[0057] like Figure 1 As shown, according to the normal flow of blood, the heart valve prosthesis 100 is axially divided into an inflow tract A and an outflow tract B. To prevent paravalvular leakage, a skirt is provided at the inflow tract A of the heart valve prosthesis 100. The skirt can be single-layered or double-layered. A double-layered skirt means that an inner skirt 122 is provided on the inner side of the inflow tract A of the heart valve prosthesis 100 (corresponding to the inner side of the stent), and an outer skirt 123 is provided on the outer side of the inflow tract A of the heart valve prosthesis 100 (corresponding to the outer side of the stent). The outer skirt 123 is folded over the outer side of the stent 110. A single-layered skirt means that the inner skirt 122 is only provided on the inner side of the inflow tract A. The inner skirt 122 is fixedly connected to the artificial valve leaflet 121. In this embodiment, the inner skirt 122 is provided on the inner side of the inflow tract A, and the outer skirt 123 is sutured at the contact position with the original valve annulus tissue to effectively prevent paravalvular leakage. The outer skirt 123 can completely wrap around the entire circumference of the stent 110 at the inflow tract A, which can effectively prevent paravalvular leakage. After the heart valve prosthesis 100 is implanted, the inner skirt 122 is close to the inner surface of the stent 110, while the outer skirt 123 is close to the tissue at the original valve site to prevent paravalvular leakage and promote endothelialization.

[0058] The integrated valve 120 can be selected from biological tissue, such as chemically stabilized tissue from heart valves of animals, such as pigs, or from pericardial tissue of animals, such as bovine (bovine pericardium) or ovine (ovine pericardium) or porcine (porcine pericardium) or equine (equine pericardium), preferably bovine pericardium tissue. In addition, artificial synthetic materials can also be used to produce the integrated valve 120. The artificial synthetic material is, for example, selected from expanded polytetrafluoroethylene or polyester. Alternatively, the artificial synthetic material can also be selected from at least one of thermoplastic polycarbonate urethane, polyether urethane, segmented polyether urethane, silicone polyether urethane, silicone-polycarbonate urethane, and ultra-high molecular weight polyethylene. The artificial synthetic material can also be selected from other biocompatible polymers, which can optionally include polyolefins, elastomers, polyethylene glycol, polyether sulfone, polysulfone, polyvinylpyrrolidone, polyvinyl chloride, other fluoropolymers, silicone polyesters, siloxane polymers and / or oligomers, and / or polylactones, and block copolymers using them, in particular a combination of one or more of these materials.

[0059] The suture 130 is selected from conventional medical suture materials, including but not limited to PTFE, ePTFE, and PE, and the like.

[0060] It should be noted that, Figure 2a is the two-dimensional form of the integrated valve 120 after deployment, i.e. the form when not folded for use. As Figure 2a shown, in some embodiments, the length of the artificial leaflet 121 in the outflow portion (corresponding to L1) is greater than the length in the inflow portion (corresponding to L2), so that the artificial leaflet 121 can be freely opened and closed, better meeting the clinical needs. In some embodiments, the length of the skirt in the outflow portion is greater than or equal to the length in the inflow portion (corresponding to L2), thereby improving the performance of the skirt. In one of the embodiments, the length of the inner skirt 122 in the outflow portion (corresponding to L1) is greater than or equal to the length in the inflow portion (corresponding to L2), so that the inner skirt 122 is in close contact with the stent 110, so that the blood flows smoothly into the valve, reducing the risk of thrombosis. In one of the embodiments, the length of the outer skirt 123 in the outflow portion (corresponding to L3) is greater than or equal to the length in the inflow portion (corresponding to L2), so that the outer skirt 123 is in close contact with the tissue, better preventing paravalvular leakage. In this embodiment, the length of the inner skirt 122 in the outflow portion is greater than the length in the inflow portion, and the length of the outer skirt 123 in the outflow portion is greater than the length in the inflow portion, which is more effective.

[0061] In the illustrated embodiment, the integrated valve 120 presents a waist shape with a small middle and large ends, i.e., L3>L2, L1>L2. At this time, the artificial valve leaflets 121 can freely open and close, better meeting the clinical needs, while the inner skirt 122 can be closely attached to the stent 110 in a relatively compact manner, so that the blood flows smoothly into the valve, reducing the risk of thrombosis, and the outer skirt 123 can be better attached to the tissue, better preventing paravalvular leakage.

[0062] Referring to Figure 2a It can be understood that the inner skirt 122 has a first side 1222 engaged with the outer skirt 123, and the first side 122 is the inflow portion of the integrated valve 120, which includes the inflow portion of the artificial valve leaflets 121, the inflow portion of the inner skirt 122, and the inflow portion of the outer skirt 123. In addition, the outer skirt 123 has a second side 1232 away from the first side 1222, and the second side 1232 is the outflow portion of the outer skirt 123. The outer skirt 123 is folded outward along the first side 1222 of the inner skirt 122 to the outside of the stent 110, and after folding, the length of the outer skirt 123 in the outflow portion (i.e., L3) is greater than the length in the inflow portion (i.e., L2) along the normal flow direction of the blood.

[0063] As Figure 2b shown, the second side 1232 of the outer skirt 123 can be arranged according to the mesh shape of the stent 110, so that the second side 1232 of the outer skirt 123 matches the mesh shape. It should be understood that the stent 110 includes a plurality of stent rings (not labeled) arranged in sequence along the axial direction thereof, and each stent ring is formed by a plurality of stent bars 111 connected end to end. The waveform shape of the stent ring is generally sawtooth or sinusoidal. Accordingly, the second side 1232 of the outer skirt 123 can be sawtooth or sinusoidal, which is beneficial to save materials.

[0064] Further, before suturing, a certain amount of redundancy is configured for the artificial valve leaflets 121, so that the length (L1) of the artificial valve leaflets 121 when unfolded is slightly larger than the inner circumference of the stent 110, so that the artificial valve leaflets 121 have a certain amount of redundancy in the circumferential direction of the stent 110, and further, after the artificial valve leaflets 121 are folded into a three-dimensional shape, the artificial valve leaflets 121 can more smoothly and freely open and close, better meeting the clinical needs.

[0065] Since the inner skirt 122 needs to be closely attached to the stent 110, therefore, before suturing, a certain amount of redundancy is not configured for the inner skirt 122, so that the length (L2) of the inner skirt 122 when unfolded is slightly smaller than the inner circumference of the stent 110, or equal to the inner circumference of the stent 110, and further, after the inner skirt 122 is folded into a three-dimensional shape, the inner skirt 122 is closely attached to the inner surface of the stent 110, so that the blood flows smoothly into the valve.

[0066] Further, before suturing, the outer skirt 123 is configured with a certain amount of redundancy, so that the length (L3) of the outer skirt 123 when unfolded is slightly larger than the outer circumference of the stent 110, so that after the outer skirt 123 is folded into a three-dimensional shape, the outer skirt 123 can better adhere to the tissue and prevent paravalvular leakage.

[0067] The production and preparation method of the integrated valve 120 can be various, such as cutting, cutting, injection molding, thermoforming, etc., and at least one of them can be selected to perform.

[0068] Referring to Figure 2a , each leaflet of the artificial valve leaflet 121 includes a leaflet free edge portion 1211, a clamping ear 1212, and a leaflet fixed portion 1213, and the leaflet free edge portion 1211 and the leaflet fixed portion 1213 are connected by the clamping ear 1212. In Figure 2a , the left side of the leaflet free edge portion 1211 and the left side of the leaflet fixed portion 1213 are connected by the left clamping ear 1212, and the right side of the leaflet free edge portion 1211 and the right side of the leaflet fixed portion 1213 are connected by the right clamping ear 1212. The artificial valve leaflet 121 also includes a leaflet transition portion 1214, which serves as a transition zone between the artificial valve leaflet 121 and the inner skirt 122. Functionally, the leaflet transition portion 1214 can function as an inner skirt. The shape of the leaflet free edge portion 1211 is not particularly limited by the present application, such as flat or arcuate, arcuate or concave in the inflow direction or protruding in the outflow direction. In addition, the leaflet fixed portion 1213 is usually arcuate.

[0069] Considering that the clamping ear 1212 is subjected to greater stress, therefore, the clamping ear 1212 requires more suturing allowance than the leaflet fixed portion 1213 to meet the strength requirement, and along the normal flow direction of blood, the artificial valve leaflet 121 opens and closes more in the outflow portion than in the inflow portion. It also needs more redundancy, therefore, the length (L1) of the artificial valve leaflet 121 in the outflow portion is greater than the length (L2) in the inflow portion, so that the artificial valve leaflet 121 can be freely opened and closed while meeting the strength requirement.

[0070] As shown in Figure 2a , when unfolded, the artificial valve leaflet 121 has two opposite leaflet suturing edges 1215. As shown in Figure 3As shown, when folded, the two leaflet sewing edges 1215 are sewn together by the sewing thread 130, and the artificial valve leaflet 121 is folded into a three-dimensional shape. Then, the artificial valve leaflet 121 is sewn along the stent rod 111 and arranged on the side of the stent 110 to reduce the overall size after sewing. When the artificial valve leaflet 121 is sewn, the leaflet fixing portion 1213 is sewn and fixed to the stent rod 111 in the circumferential direction of the stent 110, and the ear 1212 is sewn and fixed to the stent rod 111 in the axial direction of the stent 110.

[0071] As shown, when unfolded, the inner skirt 122 has two opposite inner skirt sewing edges 1221, and the outer skirt 123 has two opposite outer skirt sewing edges 1231. When folded, the two inner skirt sewing edges 1221 are sewn together by the sewing thread 130, and the inner skirt 122 is folded and placed on the inner side of the stent 110. Then, the inner skirt 122 is sewn to the stent rod 111. Similarly, the two outer skirt sewing edges 1231 are sewn together by the sewing thread 130, and the outer skirt 123 is folded and placed on the outer side of the stent 110. Then, the second side 1232 of the outer skirt 123, which is away from the inner skirt 122, is sewn to the stent rod 111. Figure 2a Preferably, the height H4 of the outer skirt 123 is greater than the height H3 of the inner skirt 122, so that the valve has a high tolerance rate after implantation and further reduces paravalvular leakage. Preferably, the height H2 of the artificial valve leaflet 121 and the length (L2) of the inner skirt 122 when unfolded have a certain relationship, and the ratio of H2 / L2 is preferably 0.15-0.3, more preferably 0.2-0.25, which can ensure that the artificial valve leaflet 121 has a good opening and closing shape. Preferably, the ear height H1 of the artificial valve leaflet 121 and the length (L2) of the inner skirt 122 when unfolded have a certain relationship, and the ratio of H1 / L2 is preferably 0.01-0.05, more preferably 1 / 70-1 / 50, which can ensure that the valve has sufficient closing margin and reduce regurgitation through the center of the valve.

[0072] It should also be understood that when the valve is formed by sewing multiple parts together, regurgitation is likely to occur at the seam. Therefore, more sewing stitches are needed to reduce the gap and thus reduce regurgitation, but more sewing stitches can easily damage the material and thus reduce the service life of the valve. The one-piece valve 120 of the present application can reduce the number of sewing stitches when sewing, which reduces regurgitation while reducing damage to the valve and improving the service life of the valve.

[0073] As shown, when unfolded, the inner skirt 122 has two opposite inner skirt sewing edges 1221, and the outer skirt 123 has two opposite outer skirt sewing edges 1231. When folded, the two inner skirt sewing edges 1221 are sewn together by the sewing thread 130, and the inner skirt 122 is folded and placed on the inner side of the stent 110. Then, the inner skirt 122 is sewn to the stent rod 111. Similarly, the two outer skirt sewing edges 1231 are sewn together by the sewing thread 130, and the outer skirt 123 is folded and placed on the outer side of the stent 110. Then, the second side 1232 of the outer skirt 123, which is away from the inner skirt 122, is sewn to the stent rod 111.

[0074] Figure 4 ​As shown, when the integrated valve 120 is stitched with the stent 110: (1) the number of stitches of the leaflet fixing portion 1213 is at least 3 stitches, and generally no more than 4 stitches, in the embodiment, the number of stitches of the leaflet fixing portion 1213 is 3 stitches, which are respectively at the middle a, the left middle b and the right middle c of the leaflet fixing portion 1213; (2) the number of stitches of the clamping ear 1212 is at least 2 stitches, and generally no more than 3 stitches, in the embodiment, the number of stitches of the clamping ear 1212 is 2 stitches, which are respectively at the upper side d and the lower side e of the clamping ear 1212; (3) the first side 1222 of the inner skirt 122 is stitched with the stent 110 in the circumferential direction at least 3 stitches, and no more than 4 stitches, and the stitches are arranged at equal angles along the circumferential direction of the stent 110; (4) the second side 1232 of the outer skirt 123 is stitched with the stent 110 in the circumferential direction at least 3 stitches, and no more than 4 stitches, and the stitches are arranged at equal angles along the circumferential direction of the stent 110; (4) the leaflet stitching edge 1215, the inner skirt stitching edge 1221 and the outer skirt stitching edge 1231, each of which is stitched with the stent 110 in the axial direction at least 2 stitches, in the embodiment, the number of stitches of each of the stitching edges is 2 stitches, which are respectively at the upper side and the lower side along the blood flow direction. The simplified stitching method can maximize the reduction of damage to the material, increase the durability of the valve, simplify the stitching process, reduce the production cost, and improve the production efficiency.

[0075] The embodiment of the present application also provides a preparation method of the heart valve prosthesis, which is used for preparing the heart valve prosthesis 100 described in the embodiment, and the preparation method comprises the following steps:

[0076] The integrated valve material 10 is obtained, and the integrated valve material 10 sequentially undergoes the cutting, pre-shaping and folding processes, and finally the folded integrated valve material 10 is stitched on the stent 110 to obtain the complete heart valve prosthesis 100.

[0077] Further, the pre-shaping process comprises the following steps: the cut integrated valve material is pre-shaped by using a shaping tool 200; during the pre-shaping process, the cut integrated valve material 10 is placed on a shaping mold 230 of the shaping tool 200, a gravity block 240 of the shaping tool 200 is used to apply a circumferential tension to the integrated valve material 10 on the shaping mold 230, and the integrated valve material 10 is tensioned, and the pre-shaped valve material 10 is pre-shaped under a predetermined condition, which can be specifically referred to Figure 7a and Figure 7b . The pre-determined condition is set according to the valve material 10. If the valve material 10 is biological tissue, the pre-determined condition is cross-linking agent shaping. If the valve material 10 is a high polymer material, the pre-determined condition is heat shaping. Generally, the shaping mold 230 and the gravity block 240 are both placed in a treatment chamber, so that the valve material 10 on the shaping mold 230 is pre-shaped in the treatment chamber with the pre-determined condition.

[0078] As shown in Figures 7a to 7b , and Figures 8a to 8b in one embodiment, the processing chamber is a fixed container 210 for containing a cross-linking agent, which constitutes the predetermined condition for the predetermined shaping. The cross-linking agent is not particularly limited, and is generally glutaraldehyde, genipin, etc. The cross-linking agent is conducive to the shaping of the integrated valve material 10 prepared from the biological tissue, and does not damage the structure of the integrated valve material 10.

[0079] In another embodiment, the processing chamber is a temperature and humidity chamber configured to have a certain temperature, humidity, and processing time, which constitute the predetermined condition for the heat shaping. Further, the temperature is 60-120°C, preferably 80-100°C, the humidity is 10-80%, preferably 30-60%, and the processing time is 1-6 hours, preferably 2-4 hours. The predetermined conditions given herein can ensure a better predetermined shaping effect.

[0080] Further, the folding process includes placing the predetermined shaped integrated valve material 10 in a mold core 300 to fold the predetermined shaped integrated valve material 10 into a three-dimensional shape by the mold core 300. For details, see Figure 10a , and 10b Compared with manual folding, the mold core 300 folding has a better effect, and is more convenient and faster.

[0081] In an exemplary embodiment, as shown in Figure 6a , the process of preparing the heart valve prosthesis 100 includes the following steps S(1) to S(5).

[0082] Step S(1): Obtain pericardial tissue. The pericardial tissue serves as the integrated valve material 10.

[0083] After obtaining the pericardial tissue, the pericardial tissue is quickly placed in sterile saline (e.g., sterile saline at about 4°C) for cleaning, and the cleaned pericardial tissue is stored in antibiotic-containing saline (e.g., 1% antibiotic-containing saline) for fat stripping, trimming, and cleaning of the pericardial tissue.

[0084] Step S(2): Cutting. The pericardial tissue is cut according to the specified leaflet shape. Here, the cutting can be achieved by laser cutting or blade cutting, with laser cutting being preferred.

[0085] Step S(3): Pre-shaping. The cut pericardial tissue needs to be pre-shaped to enhance the mechanical properties of the leaflets in the circumferential direction, reduce leaflet wrinkles, and improve leaflet durability. At this time, the shaping mold 230 containing the pericardial tissue and the gravity block 240 are placed together in the fixed container 210, and the pre-shaping is completed under the action of the crosslinking agent.

[0086] Step S(4): Folding. The pre-shaped pericardial tissue is folded to form a three-dimensional pericardial tissue.

[0087] Step S(5): Suturing. The folded pericardial tissue is sutured and fixed to the stent 110 to obtain a complete heart valve prosthesis 100.

[0088] like Figure 6b As shown, in another exemplary embodiment, another heart valve prosthesis 100 is prepared using the following steps S(1') to S(5'), in which the pericardial tissue of the above embodiment is replaced with a polymer material.

[0089] Specifically, step S(1'): Obtaining the polymer material. The polymer material can be selected from PU, PTFE, PET, SIBS, etc., and can be obtained through synthesis, weaving, heat setting, etc., to obtain the polymer material for artificial valves. The polymer material here is also used as the integrated valve material 10.

[0090] Step S(2'): Cutting. Cut the polymer material according to the specified petal shape. Similarly, cutting can be achieved by laser cutting or blade cutting, with laser cutting being preferred.

[0091] Step S(3'): Pre-forming. The cut polymer material is pre-formed using a pre-forming fixture 200. Pre-forming enhances the circumferential mechanical properties of the valve leaflets, reduces leaflet wrinkles, and improves valve durability. Specifically, the pre-forming mold 230 containing the polymer material and the gravity block 240 are placed together in a temperature and humidity chamber, and the heat pre-forming is completed in the chamber with specific temperature, humidity, and processing time.

[0092] Step S(4'): Folding. The pre-shaped polymer material is also folded using the mold core 300, and excess polymer material is trimmed off.

[0093] Step S(5'): Suturing. The folded polymer material is sutured and fixed to the stent 110 to obtain a complete heart valve prosthesis 100.

[0094] like Figure 7a and Figure 7bAs shown, the embodiment of the present application also provides a shaping tool 200 for pre-shaping the cut integrated valve material 10. In the following description, the pericardial tissue is exemplarily described.

[0095] In one embodiment, the shaping tool 200 includes a fixed container 210, a support seat 220, a shaping mold 230, and a gravity block 240. The container 210 contains a crosslinking agent. The support seat 220 is arranged in the container 210 and is used to mount the shaping mold 230. The shaping mold 230 is used to place the cut pericardial tissue. The weight of the gravity block 240 is set according to the needs, which is used to tension the pericardial tissue. The gravity block 240 can be selected as a weight, and the weight of the weight is 1g-20g, preferably 5g-15g.

[0096] When pre-shaping is needed, first, the cut pericardial tissue is loaded into the shaping mold 230, and a gravity block 240 with a suitable weight is loaded at each end of the pericardial tissue along the length direction L, so that the gravity blocks 240 at both ends tension the pericardial tissue; then, the shaping mold 230 loaded with the pericardial tissue is placed on the support seat 220 and immersed in the container 210 containing the glutaraldehyde solution, and the mass percentage concentration of the glutaraldehyde solution is 0.1%-1%, preferably 0.3-0.7%, and is placed for several days, such as not less than 7 days; after the shaping is completed, the shaping mold 230 is taken out, and the pericardial tissue is taken out from the shaping mold 230.

[0097] The shaping mold 230 is made of a metal material, such as 316 stainless steel, 304 stainless steel, or a high polymer material, such as PTFE, PET, PE, etc.

[0098] As shown in Figure 8a and Figure 8b The shaping mold 230 includes a separable concave mold 2310 and a convex mold 2320, wherein the concave mold 2310 has a plurality of concave surfaces 2311 arranged in a straight line type, the convex mold 2320 has a plurality of convex surfaces 2321 arranged in a straight line type, and the convex surfaces 1321 and the concave surfaces 2311 correspond one by one. The cut pericardial tissue is placed between the convex surfaces 2321 and the concave surfaces 2311. The shapes of the convex surfaces 2321 and the concave surfaces 2311 are determined according to the shape of the required integrated valve 120. When cutting, the pericardial tissue is left with a certain amount of excess, which is convenient for connecting the gravity blocks 240 at both ends of the pericardial tissue, so that the gravity blocks 240 can be fixed on the pericardial tissue and exert a certain tension on the pericardial tissue. It should be understood that although the tension exerted by the gravity blocks 240 is along the direction of gravity, the tension exerted by the gravity blocks 240 will ultimately be mapped to the circumferential stress of the artificial valve in three-dimensional form.

[0099] Referring to Figure 9For the purpose of understanding, the three-leaflet integrated valve 120 is taken as an example for illustration. In normal use, the circumferential force F1 of the integrated valve 120 is greater than the radial force F2, so that, in the process of setting, the gravity block 240 exerts a pulling force on the pericardial tissue in the circumferential direction, thereby enhancing the mechanical properties of the integrated valve 120 in the circumferential direction, reducing the leaflet wrinkles, and improving the durability of the leaflets. Referring to FIG. 6, the integrated valve material 10 is set in the circumferential direction, i.e., the plurality of concave surfaces 2311 are arranged in the circumferential direction, and the concave surfaces 2311 are arranged upward or downward. In this embodiment, the concave surfaces 2311 are arranged upward. Figure 7a

[0100] Further, as shown in FIGS. 7 and 8, the integrated valve material 10 is set in the length direction L, i.e., the plurality of concave surfaces 2311 are arranged in the length direction L, and the concave surfaces 2311 are arranged upward or downward. In this embodiment, the concave surfaces 2311 are arranged upward. Figure 10a Figure 10b As shown in FIGS. 9 and 10, the present embodiment further provides a mold core 300 for folding the set integrated valve material 10. The mold core 300 can be made of metal, such as 316 stainless steel, 304 stainless steel, etc., or made of polymer material, such as PTFE, PET, PE, etc. The structure of the mold core 300 is determined according to the three-dimensional shape of the integrated valve 120. The set pericardial tissue is folded along the mold core 300, and the excess pericardial material is trimmed off. Finally, the folded pericardial tissue is sewn and assembled with the stent 110 to form a complete heart valve prosthesis 100.

[0101] In summary, the heart valve prosthesis provided by the present application has at least the following beneficial effects:

[0102] (1) The integrated valve can minimize the damage to the valve, increase the durability of the valve, simplify the sewing process, reduce the production cost, and improve the production efficiency.

[0103] (2) The length of the artificial valve leaflet in the outflow portion is greater than the length in the inflow portion, so that the artificial valve leaflet can be freely opened and closed, and better meet the clinical needs.

[0104] (3) The length of the inner skirt in the unfolded state is less than or equal to the inner circumference of the stent, so that the inner skirt is tightly attached to the stent in a relatively compact manner, so that the blood flows smoothly into the valve, reducing the risk of thrombosis.

[0105] (4) The length of the outer skirt in the outflow portion is greater than the length in the inflow portion, so that the outer skirt can be more tightly attached to the tissue, and better prevent paravalvular leakage.

[0106] (5) In the preparation of the integrated valve, the processing technology is optimized from the acquisition of raw materials to the sewing of the valve, greatly simplifying the valve production process. In particular, the pre-setting process is added, effectively enhancing the circumferential mechanical properties of the leaflets and improving the durability of the leaflets. ​​

[0107] Therefore, the present application improves the durability of the valve by optimizing the valve structure and the manufacturing process, and also simplifies the production process, reduces the production cost, and improves the production efficiency.

[0108] It should be noted that the various embodiments described in the specification are presented using a progression of embodiments, each presenting one or more features that are improved over previous embodiments. Each of the various embodiments described in the specification can be combined and / or combined with other embodiments described in the specification. It is intended that the specification and figures be considered as examples and not as limiting the scope of the application.

[0109] It should also be noted that, although the present application has been disclosed with reference to the preferred embodiments, the above embodiments are not intended to limit the present application. Any person skilled in the art, without departing from the scope of the present application, can make many possible changes and modifications to the above disclosed technical content of the present application, or modify it into equivalent embodiments. Therefore, any simple modification, equivalent change and modification made to the above embodiments without departing from the technical solution of the present application, in accordance with the technical essence of the present application, are still within the scope of protection of the present application.

[0110] It should also be understood that, unless specifically stated or indicated otherwise, the terms "first", "second", and the like in the specification are used only to distinguish different components, elements, steps, etc. in the specification, and not to indicate a logical relationship or sequence relationship between the components, elements, steps, etc.

[0111] In addition, it should be recognized that the terms described herein are used only to describe particular embodiments and do not limit the scope of the present application. It should be noted that the singular forms "a" and "an" and "the" as used in the specification and the appended claims include plural references unless the context clearly indicates otherwise. For example, a reference to "a step" or "a device" means a reference to one or more steps or devices, and can include sub-steps and sub-devices. All conjunctions used should be interpreted in the broadest sense. In addition, the word "or" should be interpreted as having the logical definition of "or", rather than the logical definition of "exclusive or", unless the context clearly indicates otherwise. In addition, the implementation of the methods and / or devices in the embodiments of the present application can include performing selected tasks manually, automatically or a combination thereof.

Claims

1. A heart valve prosthesis, characterized in that, The heart valve prosthesis comprises a stent and an integrated valve, the integrated valve comprises artificial valve leaflets and a skirt, the integrated valve is fixed with the stent by sewing thread; the skirt comprises an inner skirt connected with the artificial valve leaflets; the inner skirt is arranged at the inner side of the stent; the ratio of the height of the artificial valve leaflets to the length of the inner skirt when unfolded is 0.15-0.3; the ratio of the height of the artificial valve leaflet clamping ear to the length of the inner skirt when unfolded is 0.01-0.

05.

2. The heart valve prosthesis of claim 1, characterized in that The length of the artificial valve leaflets in the outflow tract part is greater than the length in the inflow tract part.

3. The heart valve prosthesis of claim 1 or 2, characterized in that The length of the skirt in the outflow tract part is greater than or equal to the length in the inflow tract part.

4. The heart valve prosthesis of claim 3, characterized in that The skirt further comprises an outer skirt, the outer skirt is folded at the outer side of the stent, the length of the inner skirt in the outflow tract part is greater than or equal to the length in the inflow tract part, and / or the length of the outer skirt in the outflow tract part is greater than or equal to the length in the inflow tract part.

5. The heart valve prosthesis of claim 2, characterized in that The length of the artificial valve leaflets when unfolded is greater than the inner circumference of the stent.

6. The heart valve prosthesis of claim 4, characterized in that The length of the inner skirt when unfolded is less than or equal to the inner circumference of the stent, and the length of the outer skirt when unfolded is greater than the outer circumference of the stent.

7. The heart valve prosthesis of claim 1 or 2, characterized in that The skirt further comprises an outer skirt, the outer skirt is folded at the outer side of the stent, and the height of the outer skirt is greater than the height of the inner skirt.

8. The heart valve prosthesis of claim 1 or 2, characterized in that Each valve of the artificial valve leaflets comprises a valve leaflet free edge part, a clamping ear, a valve leaflet fixed part and a valve leaflet transition part, the clamping ear is arranged between the two ends of the valve leaflet free edge part and the two ends of the valve leaflet fixed part, the valve leaflet transition part is arranged between the valve leaflet fixed part and the skirt, the number of sewing stitches of the valve leaflet fixed part is 3, the number of sewing stitches of the clamping ear is 2, the number of sewing stitches of the skirt in the circumferential direction of the stent is 3-4, and the number of sewing stitches of the sewing edge of the artificial valve leaflets and the skirt in the axial direction of the stent is 2.

9. A method of manufacturing a heart valve prosthesis for manufacturing a heart valve prosthesis according to any one of claims 1 to 8, characterized in that The preparation method comprises: obtaining an integrated valve material, making the integrated valve material sequentially pass through cutting, pre-shaping and folding processes, and finally sewing the folded integrated valve material on a stent to obtain a heart valve prosthesis; the pre-shaping process comprises: using a shaping tool to pre-shape the cut integrated valve material, the shaping tool comprises a shaping die and a gravity block, the shaping die comprises separable concave and convex dies, the concave die has a plurality of concave surfaces arranged in a straight line, and the convex die has a plurality of convex surfaces arranged in a straight line, the convex surfaces and the concave surfaces correspond one by one; during pre-shaping, the cut integrated valve material is placed between the convex surfaces and the concave surfaces, the gravity block is used to apply a circumferential tensile force to the integrated valve material placed on the shaping die, and the integrated valve material is tensioned, and the valve material is pre-shaped under predetermined conditions.

10. The method of producing a heart valve prosthesis according to claim 9, characterized in that The valve material is pre-shaped in a treatment chamber containing a crosslinking agent, or the valve material is pre-shaped in a treatment chamber with a certain temperature, humidity and treatment time.

11. The method of producing a heart valve prosthesis according to claim 10, characterized in that The crosslinking agent is glutaraldehyde or genipin.

12. The method of producing a heart valve prosthesis according to claim 10, characterized in that The temperature is 60-120 DEG C, the humidity is 10-80%, and the treatment time is 1-6 hours.

13. The method of manufacturing a heart valve prosthesis according to any one of claims 9-12, characterized in that, The folding procedure includes placing the pre-shaped integrated valve material in a mold core to fold the pre-shaped integrated valve material into a three-dimensional shape by the mold core.

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