Valve stent, method for processing valve stent, and artificial valve

Abstract

The present application provides a valve stent, a method for processing a valve stent, and an artificial valve. The valve stent is formed by cutting a metal tube and has a cut state and an expanded state. The valve stent comprises a plurality of grid cell structure units distributed in a circumferential direction of the valve stent and extending in an axial direction of the valve stent. Each grid cell structure unit comprises a plurality of quadrilateral grid cells, and the plurality of quadrilateral grid cells comprise at least one end grid cell proximal to the heart, at least one middle supporting grid cell and at least one end grid cell distal to the heart that are sequentially arranged from a first axial end to a second axial end in the axial direction of the valve stent. Each quadrilateral grid cell comprises four stent rods sequentially connected end to end. Each stent rod comprises a straight rod section and a connecting section. In the cut state, the straight rod sections of two stent rods, opposite to each other in the circumferential direction of the valve stent, of each quadrilateral grid cell gradually diverge from each other from the middle to the end of the quadrilateral grid cell in the axial direction to form an included angle, wherein the included angle of the middle supporting grid cell is less than or equal to 12 degrees.

Description

Valve stent, valve stent processing method and artificial valve

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure is based on and claims priority to a Chinese patent application with application number 202410039309.5, application date January 11, 2024, and invention name “Valve Stent, Valve Stent Processing Method and Artificial Valve”. The disclosure content of this Chinese patent application is hereby introduced as a whole into this disclosure. Technical Field

[0003] The present application relates to the field of medical devices, and in particular to a valve stent, a method for processing the valve stent, and an artificial valve. Background Art

[0004] In the related art, valve stents of some artificial valves are formed by cutting metal pipes.

[0005] The valve stent formed by metal cutting is made of the same material and process as the whole, and is prone to breakage during processing. It also faces problems with safety and clinical effectiveness during use.

[0006] The above statements are only used to provide background technical information related to the present application and do not necessarily constitute prior art. Summary of the Invention

[0007] The purpose of this application is to provide a valve stent, a processing method for a valve stent and an artificial valve, aiming to alleviate or solve the problem that the valve stent formed by cutting metal pipes is easy to break during the processing and has safety and clinical effectiveness problems during use.

[0008] A first aspect of the present application provides a valve stent, which is formed by cutting a metal tube and has a cut state and an expanded state, including a plurality of grid structure units distributed along the circumference of the valve stent and extending along the axial direction of the valve stent, wherein the grid structure unit includes a plurality of quadrilateral grids, and the plurality of quadrilateral grids include at least one grid close to the heart end, at least one middle support grid and at least one grid away from the heart end, which are sequentially arranged along the axial direction of the valve stent from the first axial end to the second axial end, each of the quadrilateral grids includes four stent rods connected end to end in sequence, and the stent rod includes a straight rod section and a connecting section, and the The straight rod segments form the grid body of the quadrilateral grid, the connecting segments of each stent rod form the corners of the quadrilateral grid, the adjacent stent rods of each quadrilateral grid are connected by the connecting segments, and the corners of the axial middle parts of the corresponding quadrilateral grids of adjacent grid structure units are connected. In the state after cutting, the straight rod segments of the two stent rods of each quadrilateral grid that are opposite to each other along the circumference of the valve stent gradually move away from each other from the axial middle part to the end part of the quadrilateral grid to form an angle, wherein the angle of the straight rod segments of each two stent rods of the middle support grid that are opposite to each other along the circumference of the valve stent is less than or equal to 12°.

[0009] In the valve stent described in some embodiments,

[0010] The plurality of quadrilateral grids include two middle support grids, and the included angle between the straight rod segments of each two stent rods opposite to each other along the circumference of the valve stent of each middle support grid is less than 11.74°; or

[0011] The plurality of quadrilateral grids include a middle support grid, wherein the included angle between the straight rod segments of every two stent rods opposite to each other along the circumference of the valve stent in the middle support grid is less than 6.14°.

[0012] In the valve stent described in some embodiments,

[0013] The plurality of quadrilateral grids include two middle support grids, and the included angle between the straight rod segments of each two stent rods opposite to each other along the circumference of the valve stent of each middle support grid is 5.0° to 11.0°; or

[0014] The multiple quadrilateral grids include a middle support grid, and the included angle between the straight rod segments of every two stent rods opposite to each other along the circumference of the valve stent in the middle support grid is 2.5° to 5.5°.

[0015] In the valve stent described in some embodiments, in the post-cut state, the angle between the straight rod segments of the two stent rods of the middle support grid near the first axial end is equal to or different from the angle between the straight rod segments of the two stent rods near the second axial end.

[0016] In the valve stent described in some embodiments, the connecting section of the stent rod includes two curved connecting sections provided at both ends of the straight rod section, and adjacent stent rods of the quadrilateral grid are connected by the curved connecting sections;

[0017] The curved connecting section at one end of the support rod close to the end of the quadrilateral grid is bent toward the inner side of the quadrilateral grid;

[0018] The curved connecting section at one end of the support rod close to the middle of the quadrilateral grid is bent toward the outside of the quadrilateral grid.

[0019] In the valve stent described in some embodiments, the curved connecting segment is an arc connecting segment, and the ratio of the length of the straight rod segment to the inner radius of the arc connecting segment ranges from 4 to 30.

[0020] In the valve stent described in some embodiments, the straight rod segment is connected to the curved connecting segment via a curved transition segment, and the curved transition segment has a bending direction opposite to that of the curved connecting segment.

[0021] In the valve stent described in some embodiments, the curved transition section is an arc transition section, and the ratio of the inner radius of the arc transition section to the length of the straight rod section ranges from 0.25 to 0.75.

[0022] In the valve stent described in some embodiments, the curved connecting segment is an arc connecting segment; wherein,

[0023] The length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod near the first axial end of the grid near the end of the heart is equal to or different from the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod near the second axial end; and / or

[0024] The length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod close to the first axial end, which is away from the heart end grid, is equal to or different from the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod close to the second axial end; and / or

[0025] The axial length of the valve stent between the centers of the arc transition sections at both ends of the stent rod of the middle support grid close to the first axial end is equal to or different from the axial length of the valve stent between the centers of the arc transition sections at both ends of the stent rod close to the second axial end.

[0026] In the valve stent described in some embodiments, the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod near the axial first end of the grid near the end of the heart is smaller than the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod near the axial second end; and / or

[0027] The length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod close to the first axial end away from the heart end grid is greater than the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod close to the second axial end.

[0028] In the valve stent described in some embodiments, the ratio of the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod near the first axial end of the grid near the end of the heart to the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod near the second axial end is 0.65 to 1.00; and / or

[0029] The ratio of the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod close to the second axial end away from the heart end grid to the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod close to the first axial end is 0.65 to 1.00.

[0030] In the valve stent described in some embodiments,

[0031] The curved connecting section is an arc connecting section;

[0032] The plurality of quadrilateral grids include a grid close to the heart end, a middle support grid and a grid far from the heart end, which are sequentially arranged along the axial direction of the valve stent from the axial first end to the axial second end;

[0033] The length between the centers of the arc transition sections at both ends of each stent rod of the middle support grid along the axial direction of the valve stent is in the range of 3.05 to 8.22 mm; and / or

[0034] The length between the centers of the arc transition sections at both ends of each stent rod of the grid close to the heart end along the axial direction of the valve stent is in the range of 3.55 to 12.50 mm; and / or

[0035] The length between the centers of the arc transition sections at both ends of each stent rod of the grid at the end far from the heart along the axial direction of the valve stent is in the range of 3.55 to 12.50 mm.

[0036] In the valve stent described in some embodiments,

[0037] The curved connecting section is an arc connecting section;

[0038] In each of the grid structure units,

[0039] in,

[0040] L i is the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod of the quadrilateral grid close to the first axial end;

[0041] L j is the length along the axial direction of the valve stent between the centers of the arc transition sections at both ends of the stent rod of the quadrilateral grid close to the second axial end;

[0042] α i is the included angle between the straight rod sections of the two support rods of the quadrilateral grid close to the first axial end;

[0043] α j is the included angle between the straight rod sections of the two support rods of the quadrilateral grid close to the second axial end.

[0044] In the valve stent described in some embodiments, the valve stent further includes a plurality of connecting rods, wherein

[0045] The grid near the end of each grid structure unit is connected to the middle support grid via one of the connecting rods, or along the circumference of the valve stent, a grid structure unit whose grid near the end of the heart is not connected to the middle support grid is provided with a grid structure unit whose grid near the end of the heart is connected to the middle support grid via one of the connecting rods; and / or

[0046] The grid of the end portion away from the heart and the middle support grid of each grid structure unit are connected by a connecting rod, or along the circumference of the valve stent, a grid structure unit whose end portion away from the heart and the middle support grid are not connected is provided with a grid structure unit whose end portion away from the heart and the middle support grid are connected by a connecting rod.

[0047] In the valve stent described in some embodiments, in the expanded state, the outer diameter D2 of the axial first end and the axial second end of the valve stent is larger than the outer diameter D1 of the axial middle portion.

[0048] In the valve stent described in some embodiments, in the expanded state, the outer diameter D1 of the axial middle portion of the valve stent ranges from 18.0 to 32.0 mm, and the outer diameter D2 of the axial first end and the axial second end of the valve stent ranges from 20.0 to 54.0 mm.

[0049] In the valve stent described in some embodiments, in the expanded state, the total height H1 of the valve stent is 30.0 to 60.0 mm, and the height H2 of the middle support grid is 12.0 to 30.0 mm.

[0050] In the valve stent described in some embodiments, in the expanded state, the valve stent transitions from the axial middle portion to the axial first end sequentially through a first concave arc segment and a first convex arc segment, and transitions from the axial middle portion to the axial second end sequentially through a second concave arc segment and a second convex arc segment; wherein the cross section of the first concave arc segment passing through the axis of the valve stent has a radius of R A The first concave arc is concave toward the inner side of the valve stent; the cross section of the first convex arc segment passing through the axis of the valve stent is a radius of R B The first convex arc protrudes toward the outside of the valve stent; the cross section of the second concave arc segment passing through the axis of the valve stent is a radius of R C The second concave arc is concave toward the inner side of the valve stent; the cross section of the second convex arc segment passing through the axis of the valve stent is a radius of R D A second convex arc protruding toward the outside of the valve stent; wherein R A and R C The range is 3.0~15.0mm,

[0051] R B and R D The range is 3.0~15.0mm.

[0052] A second aspect of the present application provides a method for processing the valve stent according to the first aspect of the present application, the processing method comprising:

[0053] The stent cutting step includes cutting a metal tube into a blank having the same structure as the valve stent in a cut state, and making two stent rods of the quadrilateral grid of the blank that are opposite to each other along the circumference of the valve stent gradually move away from each other from the axial middle portion to the end portion of the quadrilateral grid to form an angle, wherein the angle between the straight rod sections of each two stent rods of the middle support grid that are opposite to each other along the circumference of the valve stent is less than or equal to 12°;

[0054] a stent pre-forming step, comprising pre-forming the blank in a cut state in multiple steps, and annealing after each pre-forming step to form the blank in an expanded state; and

[0055] The stent shaping step is to shape the blank in the expanded state after the stent is pre-shaped by using a shaping mold to form the valve stent in the cut state.

[0056] In the processing method described in some embodiments, in the stent preforming step,

[0057] The multi-step pre-forming is 2 to 6 steps of pre-forming; and / or,

[0058] The maximum strain per pre-setting step is less than 12%; and / or,

[0059] The annealing temperature of the annealing treatment is 400-500°C, the holding time is 2-21 minutes, and the cooling method is water cooling. In the processing method described in some embodiments, the stent shaping step includes:

[0060] Fixing the blank in the expanded state in the shaping die;

[0061] The blank fixed in the shaping mold is subjected to annealing and shaping treatment, wherein the annealing temperature of the annealing and shaping treatment is 500-550° C., the holding time is 2-30 minutes, and the cooling method is water cooling.

[0062] The third aspect of the present application also provides an artificial valve, including a valve stent, and the valve stent is the valve stent described in the first aspect of the present application.

[0063] Based on the valve stent, valve stent, valve stent processing method and artificial valve provided by the present application, in the state after cutting, the straight rod sections of the two stent rods of each quadrilateral grid that are opposite to each other along the circumference of the valve stent gradually move away from each other from the axial middle to the end of the quadrilateral grid to form an angle, wherein the angle between the straight rod sections of each two stent rods of the middle support grid that are opposite to each other along the circumference of the valve stent is less than or equal to 12°, which is conducive to alleviating or solving the problem that the valve stent formed by cutting metal pipes is easy to break during the processing, and is also conducive to improving the safety and clinical effectiveness during use.

[0064] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The drawings described herein are used to provide further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application.

[0066] FIG1 is a schematic diagram of the three-dimensional structure of an artificial valve in one direction according to an embodiment of the present application, wherein the valve stent is in an expanded state.

[0067] FIG2 is a schematic diagram of the three-dimensional structure of the artificial valve in another direction according to an embodiment of the present application, wherein the valve stent is in an expanded state.

[0068] FIG3 is a schematic diagram of the three-dimensional structure of the artificial valve in another direction according to an embodiment of the present application, wherein the valve stent is in an expanded state and the sealing membrane is removed.

[0069] FIG4 is a schematic diagram of the three-dimensional structure of the valve stent of the artificial valve according to an embodiment of the present application after cutting.

[0070] FIG5 is a schematic diagram of the front structural view of the valve stent of the artificial valve in the cut state according to an embodiment of the present application.

[0071] 6 to 9 are schematic structural diagrams of a grid structure unit of the valve stent shown in FIG5 in a cut state.

[0072] FIG10 is a schematic diagram of the front structural view of the valve stent of the artificial valve in the expanded state according to an embodiment of the present application.

[0073] FIG11 is a schematic structural diagram of the artificial valve in the expanded state according to an embodiment of the present application, wherein the sealing membrane is removed and the finite element mesh during finite element analysis is shown.

[0074] FIG12 is a flow chart of a method for processing a valve stent of an artificial valve according to an embodiment of the present application. DETAILED DESCRIPTION

[0075] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0076] Unless otherwise specified, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to actual proportional relationships. Technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0077] In the description of this application, it should be understood that the use of words such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above words have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0078] In the description of this application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of this application; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0079] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0080] As shown in Figures 1 to 11, an embodiment of the present application provides an artificial valve and a valve stent 100. As shown in Figure 12, an embodiment of the present application also provides a method for processing the valve stent 100 and the artificial valve.

[0081] As shown in Figures 1 to 11, the valve stent 100 of an embodiment of the present application is formed by cutting metal tubing and has both a cut state and an expanded state. The valve stent 100 includes a plurality of grid structural units A distributed circumferentially and extending axially along the valve stent 100. The grid structural units A comprise a plurality of quadrilateral grids. These quadrilateral grids include at least one grid 120 located near the heart end, at least one mid-portion support grid 130, and at least one grid 140 located away from the heart end, arranged sequentially along the axial direction of the valve stent 100 from the first axial end to the second axial end. Each quadrilateral grid comprises four stent rods B connected end to end. The stent rods B comprise straight rod segments B1 and connecting segments B2. The straight rod segments B1 of each stent rod B form the main body of the quadrilateral grid. The connecting segments B2 of each stent rod B form the corners of the quadrilateral grid. The axial mid-portion corners of the corresponding quadrilateral grids of adjacent grid structural units A are connected. Adjacent stent rods B of each quadrilateral grid are connected by connecting segments B2. As shown in Figures 4 to 9 , after cutting, the straight rod segments B1 of two opposing stent rods B in the quadrilateral grid along the circumference of the valve stent 100 gradually move away from each other from the axial center of the quadrilateral grid toward the ends, forming an angle. Specifically, the angle between the straight rod segments B1 of each two opposing stent rods B in the central support grid 130 along the circumference of the valve stent 100 is less than or equal to 12°.

[0082] In the valve stent 100 of the embodiment of the present application, in the state after cutting, the straight rod sections of the two stent rods of each quadrilateral grid that are opposite to each other along the circumference of the valve stent gradually move away from each other from the axial middle to the end of the quadrilateral grid to form an angle, wherein the angle between the straight rod sections B1 of each two stent rods B of the middle support grid 130 that are opposite to each other along the circumference of the valve stent 100 is less than or equal to 12°, which is conducive to alleviating or solving the problem that the valve stent 100 cut and formed by metal pipes is easy to break during the processing, and is also conducive to improving the safety and clinical effectiveness during use.

[0083] In Figures 5 to 9, the axial directions of the valve stent 100 and the grid structure unit A correspond to the left and right directions in the figures, the first axial end corresponds to the left side in the figures, and the second axial end corresponds to the right side in the figures.

[0084] In some embodiments of the valve stent, the plurality of quadrilateral grids include two middle support grids 130 , and the included angle between the straight rod segments B1 of every two stent rods B opposite to each other along the circumference of the valve stent 100 in each middle support grid 130 is less than 11.74°.

[0085] The included angle between the straight rod segments B1 of each two stent rods B of the two-layer middle support grid 130 relative to each other along the circumference of the valve stent 100 (hereinafter also referred to as the straight rod segment cutting angle) is less than 11.74°, which further helps to alleviate or solve the problem that the valve stent 100 cut and formed by metal pipes is easy to break during the processing, and further helps to improve the safety and clinical effectiveness during use.

[0086] In some embodiments of the valve stent, the plurality of quadrilateral grids include two middle support grids 130 , and the included angle between the straight rod segments B1 of each two stent rods B opposite to each other along the circumference of the valve stent 100 in each middle support grid 130 is 5.0° to 11.0°.

[0087] The cutting angle of the straight rod segments of the two-layer middle support grid 130 is in the range of 5.0° to 11.0°, and the valve stent 100 has better comprehensive performance in processing, loading and releasing, and avoiding fatigue failure.

[0088] In some embodiments of the valve stent, the plurality of quadrilateral grids include a central support grid 130 , and the included angle between the straight rod segments B1 of every two stent rods B opposite to each other along the circumference of the valve stent 100 in the central support grid 130 is less than 6.14°.

[0089] The cutting angle of the straight rod segment of the middle support grid 130 of one layer is less than 6.14°, and the valve stent 100 has good comprehensive performance in processing, loading and releasing, and avoiding fatigue failure.

[0090] In some embodiments of the valve stent, the plurality of quadrilateral grids include a central support grid 130 , and the included angle between the straight rod segments B1 of every two stent rods B opposite to each other along the circumference of the valve stent 100 in the central support grid 130 is 2.5° to 5.5°.

[0091] The cutting angle of the straight rod section of the middle support grid 130 of one layer is in the range of 2.5° to 5.5°, and the comprehensive performance of the valve stent 100 in terms of processing, loading and releasing, and avoiding fatigue failure is better.

[0092] For example, in some embodiments of the valve stent 100, considering the fatigue performance of the stent during shaping and crimping, as well as subsequent operation, the plurality of quadrilateral grids comprise a central support grid 130. In the cut state, the included angle between the straight rod segments B1 of each two stent rods B of the central support grid 130, which are opposite to each other along the circumference of the valve stent 100, can be, for example, 2.83° to 4.67°.

[0093] The cutting angle of the straight rod section of the middle support grid 130 is within the range of 2.83° to 4.67°, and the valve stent 100 has the best comprehensive performance in processing, loading and releasing, and avoiding fatigue failure.

[0094] In some embodiments of the valve stent 100, the plurality of quadrilateral grids include a grid 120 proximal to the heart end, at least one middle support grid 130, and a grid 140 distal to the heart end, sequentially arranged along the axial direction of the valve stent 100 from the first axial end to the second axial end. In embodiments not shown, the number of each of the grid 120 proximal to the heart end, the middle support grid 130, and the grid 140 distal to the heart end may be more than one.

[0095] In some embodiments of the valve stent 100, in the cut state, the included angle of the straight rod segments B1 of the two stent rods B near the first axial end of the middle support grid 130 is equal to the included angle of the two stent rods B near the second axial end.

[0096] In this setting, the deformation of the central support grid is more uniform and consistent, which helps to alleviate stress concentration.

[0097] In an embodiment not shown, the included angle between the straight rod segments B1 of the two support rods B near the first axial end of the central support grid 130 may be unequal to the included angle between the two support rods B near the second axial end.

[0098] As shown in Figures 4 to 9, in some embodiments of the valve stent 100, the connecting segment B2 of the stent rod B includes two curved connecting segments arranged at both ends of the straight rod segment B1, and adjacent stent rods B in the quadrilateral grid are connected by the curved connecting segments; the curved connecting segment at one end of the stent rod B close to the end of the quadrilateral grid is bent toward the inside of the quadrilateral grid; the curved connecting segment at one end of the stent rod B close to the middle of the quadrilateral grid is bent toward the outside of the quadrilateral grid.

[0099] Providing a curved connecting section and the bending direction of the curved connecting section is beneficial to reducing stress concentration, thereby reducing breakage during shaping processing, and can also make it easier to press and deform during use.

[0100] As shown in Figures 4 to 9, in some embodiments of the valve stent 100, the curved connecting segment is an arc connecting segment, and the ratio of the length of the straight rod segment to the inner radius R1 of the arc connecting segment ranges from 4 to 30. For example, the ratio of the length of the straight rod segment to the inner radius of the arc connecting segment can be 13, the inner radius R1 of the arc connecting segment can be 0.5 mm, and the length of the straight rod segment can be 7.5 mm.

[0101] The ratio of the inner radius of the arc connecting segment to the length of the straight rod segment can be determined based on the number of grid structure units A, the required cutting space for the stent, the width of the stent rod, and other factors. The number of grid structure units A can be, for example, 6, 9, or 12. Where feasible, a larger value improves the stent's shaping and crimping performance, as well as its fatigue resistance during subsequent operation.

[0102] The inner radius R1 of the arc connecting segment may be 0.25 to 0.93 mm. For example, in one embodiment, the number of the grid structure units A is 9, and the inner radius R1 of the corresponding arc connecting segment may be 0.49 mm.

[0103] As shown in FIG. 4 to FIG. 9 , in the valve stent 100 of some embodiments, the straight rod segment B1 is connected to the curved connecting segment through a curved transition segment B3 , and the curved transition segment B3 has a bending direction opposite to that of the curved connecting segment.

[0104] The bracket rod B adopts an Ω-shaped structure in which the bending transition section B3 and the bending connection section have opposite bending directions, so that the stress can be concentrated and distributed on the entire transition arc, which is more conducive to preventing breakage during shaping processing and can also make it easier to compress and deform during use.

[0105] As shown in FIG. 4 to FIG. 9 , in some embodiments of the valve stent 100 , the curved transition section B3 is an arc transition section, and the ratio of the inner radius of the arc transition section to the length of the straight rod section ranges from 0.25 to 0.75.

[0106] The ratio of the inner radius of the arc transition section to the length of the straight rod section is in the range of 0.25 to 0.75, which helps to more effectively alleviate stress concentration and reduce fracture during shaping, and is more easily deformed during use. For example, in a preferred embodiment, the ratio of the inner radius of the arc transition section to the length of the straight rod section can be 0.48.

[0107] The inner radius of the arc transition section can range from 2.11 to 4.55 mm. Stress concentration at the connection between a straight line and an arc occurs only at a single tangent point. The Ω-shaped structure distributes this stress concentration across the entire transition arc, preventing breakage during shaping and making it easier to deform during use. A reasonable range of inner radius values ​​effectively mitigates stress concentration using the Ω-shaped structure.

[0108] In some embodiments of the valve stent 100, the curved connecting segment is an arc connecting segment. Among them, the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial first end of the grid 120 near the heart end and the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial second end can be equal or unequal; and / or the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial first end of the grid 140 away from the heart end and the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial second end can be equal or unequal; and / or the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial first end of the middle support grid 130 and the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial second end are equal or unequal.

[0109] For example, the stent rods at the first and second axial ends of the central support grid 130 are of equal length, which facilitates more uniform deformation of the quadrilateral grid structure and alleviates stress concentration. In the quadrilateral grid structures distal from the heart and proximal to the heart, the stent rods at the first and second axial ends are of unequal length, which facilitates deformation of the quadrilateral grid into a non-uniform shape when the valve stent 100 is deployed.

[0110] In some embodiments of the valve stent 100, the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial first end near the heart end grid 120 is shorter than the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial second end; and / or the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial first end away from the heart end grid 140 is longer than the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial second end.

[0111] The length of the stent rod at the axial first end of the aforementioned grid 120 near the heart end is shorter than the length of the axial second end, which facilitates the deformation of each grid 120 near the heart end so that, in the deployed state, the diameter of the valve stent 100 at the axial first end of the portion of the grid 120 near the heart end is larger than the diameter of the axial second end. The length of the stent rod at the axial first end of the aforementioned grid 140 far from the heart end is longer than the length of the axial second end, which facilitates the deformation of each grid 140 far from the heart end so that, in the deployed state, the diameter of the valve stent 100 at the axial second end of the portion of the grid 140 far from the heart end is larger than the diameter of the axial first end.

[0112] In some embodiments of the valve stent 100, the ratio of the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial first end near the heart end grid 120 to the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial second end is 0.65 to 1.00; and / or the ratio of the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial second end away from the heart end grid 140 to the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial first end is 0.65 to 1.00.

[0113] 10 and 11 , the first convex arc (radius marked as R) of the first convex arc segment 1B of the valve stent 100 in the expanded state can be B The position of the center point of the arc) determines the ratio of the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial first end near the heart end grid 120 to the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B near the axial second end. The length of the stent rod B near the axial second end near the heart end grid 120 is appropriately increased. At the same time, in order to control the overall length of the valve stent 100, the length of the stent rod B near the axial first end near the heart end grid 120 is appropriately compressed, which is conducive to reducing the risk of fracture during the forming process.

[0114] Similarly, the second convex arc (radius marked as R) of the second convex arc segment 1D of the valve stent 100 in the expanded state shown in FIG10 and FIG11 can be D The position of the center point of the arc) determines the ratio of the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B close to the axial second end away from the heart end grid 140 to the axial length of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B close to the axial first end. The length of the stent rod B close to the axial first end away from the heart end grid 140 is appropriately increased. At the same time, in order to control the overall length of the valve stent 100, the length of the stent rod B at the axial second end away from the heart end grid 140 is appropriately compressed, which is conducive to reducing the risk of fracture during the forming process.

[0115] In some embodiments of the valve stent 100, the curved connecting section is an arc connecting section; the plurality of quadrilateral grids include a grid 120 at the end proximal to the heart, a central support grid 130, and a grid 140 at the end distal to the heart, arranged sequentially along the axial direction of the valve stent 100 from the first axial end to the second axial end. The length between the centers of the arc transition sections at both ends of each stent rod B of the central support grid 130 along the axial direction of the valve stent 100 ranges from 3.05 to 8.22 mm. For example, in some embodiments, the length between the centers of the arc transition sections at both ends of each stent rod B of the central support grid 130 along the axial direction of the valve stent 100 can be 6.45 mm.

[0116] The length between the centers of the arcuate transition sections at both ends of each stent rod B in the grid 120 near the heart end, along the axial direction of the valve stent 100, ranges from 3.55 to 12.50 mm. For example, the length between the centers of the arcuate transition sections at both ends of each stent rod B near the first axial end of the grid 120 near the heart end, along the axial direction of the valve stent 100, is 7.93 mm; the length between the centers of the arcuate transition sections at both ends of each stent rod B near the second axial end of the grid 120 near the heart end, along the axial direction of the valve stent 100, is 9.91 mm.

[0117] The length between the centers of the arcuate transition sections at both ends of each stent rod B in the distal end grid 140 along the axial direction of the valve stent 100 ranges from 3.55 to 12.50 mm. For example, the length between the centers of the arcuate transition sections at both ends of each stent rod B in the distal end grid 140 along the axial direction of the valve stent 100 is 9.91 mm; and the length between the centers of the arcuate transition sections at both ends of each stent rod B in the distal end grid 140 along the axial direction of the valve stent 100 is 7.93 mm.

[0118] In some embodiments of the valve stent 100, the curved connecting segment is an arc connecting segment; in each grid structure unit A,

[0119] Among them, L i L is the length along the axial direction of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B close to the first axial end of the quadrilateral grid; j α is the length along the axial direction of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B close to the second axial end of the quadrilateral grid; i is the included angle between the straight rod segments B1 of the two support rods B close to the first axial end of the quadrilateral grid; α j is the included angle between the straight rod segments B1 of the two support rods B close to the second axial end of the quadrilateral grid.

[0120] Only the α of the middle support grid 130 needs to be controlledi and α j , adjust the L of different support grids i and L j The length can be directly obtained after cutting, which is convenient for optimizing the parameters of the entire valve stent structure.

[0121] In some embodiments of the valve stent 100, the valve stent 100 further includes a plurality of connecting rods 150, wherein the grid 120 near the heart end of each grid structure unit A is connected to the middle support grid 130 via a connecting rod 150, or along the circumference of the valve stent 100, a grid structure unit A whose grid 120 near the heart end is not connected to the middle support grid 130 is provided; and / or the grid 140 away from the heart end of each grid structure unit A is connected to the middle support grid 130 via a connecting rod 150, or along the circumference of the valve stent 100, a grid structure unit A whose grid 140 away from the heart end is not connected to the middle support grid 130 is provided.

[0122] At the same axial position along the valve stent 100, the more circumferential connecting rods 150 there are, the greater the support force that the valve stent 100 can provide at this location, and the fewer circumferential connecting rods 150 there are, the better the flexibility and compliance of the valve stent 100 at this location.

[0123] For example, the shape of the distal end of a patient with pulmonary artery disease is more complex than the proximal end, with more non-circular surfaces. The proximal end and the valve ring position require a larger radial support force to ensure that the circular physiological shape of the pulmonary artery is maintained after the artificial valve is implanted. The grid 120 near the heart end of all grid structure units A of the valve stent 100 can be connected with the middle support grid 130 using a connector 150, so that the proximal end of the valve stent 100 forms a closed-loop structure design, while the grid 120 near the heart end of the first part of the grid structure units A of the valve stent 100 is connected with the middle support grid 130 using a connector 150, and the grid 120 near the heart end of the remaining second part of the grid structure units A is not connected with the middle support grid 130, and the first part of the grid structure units A and the second part of the grid structure units A are arranged alternately in a regular pattern, so that the distal end of the valve stent 100 forms a semi-open-loop structure design. After the artificial valve is implanted, the valve stent 100 has a higher overall radial support force on the proximal end, which is conducive to maintaining the circular physiological shape of the proximal end. The valve stent 100 has good flexibility and compliance at the distal end, which is conducive to the artificial valve having good wall adhesion performance, thereby reducing the risk of side leakage from both ends of the artificial valve and improving the overall fatigue resistance of the valve stent 100 under the torsional movement of the right heart system.

[0124] In some embodiments of the valve stent 100, the connecting rod 150 of the stent rod B is a straight rod, an S-shaped rod, an M-shaped rod, or an N-shaped rod. Different connecting rod shapes affect the axial shortening rate of the valve stent 100 in the deployed state and have different effects on the precise positioning of the valve stent 100.

[0125] As shown in FIG. 10 , in the valve stent 100 of some embodiments, in the expanded state, the outer diameters D2 of the axial first end and the axial second end of the valve stent 100 are greater than the outer diameter D1 of the axial middle portion.

[0126] The valve stent 100 forms a dumbbell-shaped structure in its expanded state. The blood vessels of patients with right ventricular and pulmonary arteries are complex and variable in shape, and most of them are enlarged and deformed. The dumbbell-shaped structure of the valve stent 100 in its expanded state helps prevent the artificial valve from shifting up and down, making it more suitable for patients with native outflow tracts.

[0127] In some embodiments of the valve stent 100, in the deployed state, the outer diameter D1 of the axial midsection of the valve stent 100 ranges from 18.0 to 32.0 mm; and in the deployed state, the outer diameters D2 of the axial first and second ends of the valve stent 100 range from 20.0 to 54.0 mm. D1 can be, for example, 20 mm, 23 mm, 26 mm, or 29 mm. D2 can be, for example, 28 mm, 32 mm, 36 mm, 40 mm, 44 mm, 48 mm, or 52 mm.

[0128] Reasonable setting of the D1 range can ensure the original valve root size of the patient as much as possible, thereby making hemodynamics more stable. Reasonable setting of the D2 range can facilitate better fixation and anastomosis of the stent according to the morphology of the patient's pulmonary artery disease, while preventing the occurrence of paravalvular leak.

[0129] In some embodiments of the valve stent, in the deployed state, the total height H1 of the valve stent 100 is 30.0 to 60.0 mm, and the height H2 of the central support grid 130 is 12.0 to 30.0 mm. Examples of H1 include 36 mm, 38 mm, 42 mm, 46 mm, 50 mm, 52 mm, and 54 mm. Examples of H2 include 14 mm, 15 mm, 16 mm, 18 mm, 20 mm, and 24 mm.

[0130] Reasonable setting of the ranges of H1 and H2 can reduce the impact of H1 on human pulmonary artery tissue after implantation while meeting processing conditions, and make the size range of H2 change according to the height of the sutured valve leaflet.

[0131] As shown in FIG10 and FIG11, in some embodiments of the valve stent 100, in the expanded state, the valve stent 100 sequentially transitions from the axial middle portion to the axial first end through the first concave arc segment 1A and the first convex arc segment 1B, and sequentially transitions from the axial middle portion to the axial second end through the second concave arc segment 1C and the second convex arc segment 1D. The cross section of the first concave arc segment 1A passing through the axis of the valve stent 100 has a radius of R A The first concave arc is concave toward the inner side of the valve stent 100; the cross section of the first convex arc segment 1B passing through the axis of the valve stent 100 is a radius R B The first convex arc protrudes toward the outside of the valve stent 100; the cross section of the second concave arc segment 1C passing through the axis of the valve stent 100 is a radius R C The second concave arc is concave toward the inner side of the valve stent 100; the cross section of the second convex arc segment 1D passing through the axis of the valve stent 100 is a radius R D A second convex arc protruding toward the outside of the valve stent 100.

[0132] A first concave arc segment 1A, a first convex arc segment 1B, a second concave arc segment 1C and a second convex arc segment 1D are set. All arc segments are transition segments during the diameter change of the valve stent 100. Smooth transition is conducive to preventing hemodynamic disorders caused by sudden changes in cross-sectional shape or size, thereby causing unexpected risks such as thrombosis.

[0133] In some embodiments of the valve stent 100, R A and R CThe range is 3.0~15.0mm, R B and R D The range is 3.0~15.0mm. D and R B They can be equal, for example, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm. C and R A They can be equal, for example, 5mm, 7mm, 9mm, 10mm, 11mm, or 13mm.

[0134] Reasonably set R D and R B and R C and R A The range can reduce the risk of fracture during stent formation and use, and can also ensure a longer fatigue service life after implantation in the human body.

[0135] As shown in Figure 12, the processing method of the valve stent of an embodiment of the present application includes: a stent cutting step, including cutting a metal tube to form a blank in a cut state having the same structure as the valve stent 100, and making the two stent rods B of the quadrilateral grid of the blank that are opposite to each other along the circumference of the valve stent 100 gradually move away from each other from the axial middle to the end of the quadrilateral grid to form an angle, wherein the angle between the straight rod segments B1 of each two stent rods B of the middle support grid 130 that are opposite to each other along the circumference of the valve stent 100 is less than or equal to 12°; a stent pre-forming step, including applying multiple steps of pre-forming to the blank in the cut state, and annealing after each step of pre-forming to form a blank in an expanded state; and a stent shaping step, shaping the blank in the expanded state after the stent pre-forming through a shaping mold to form a valve stent 100 in a cut state.

[0136] Through the above processing method, the valve stent 100 of the embodiment of the present application can be realized, so that the valve stent 100 manufactured by the processing method of the embodiment of the present application has the advantages of the valve stent 100 of the embodiment of the present application.

[0137] In some embodiments of the processing method, the stent pre-forming step includes performing multiple steps of pre-forming on the base stent, and performing annealing after each step of pre-forming.

[0138] Multi-step pre-forming, annealing treatment after each step, and control of the maximum strain of each step are beneficial to reducing fracture or damage during the pre-forming process of the stent.

[0139] In the processing method of some embodiments, in the bracket pre-forming step, the multi-step pre-forming is 2 to 6 steps of pre-forming; and / or the maximum strain of each pre-forming step is less than 12%; and / or the annealing temperature of the annealing treatment is 400 to 500°C, the holding time is 2 to 21 minutes, and the cooling method is water cooling.

[0140] The 2- to 6-step shaping process, with the maximum strain at each step being less than 12%, helps maintain the appropriate deformation range for the blank during each shaping step, thereby preventing breakage or damage during the stent shaping process. The aforementioned annealing temperature and holding time effectively remove stress from the blank within a reasonable timeframe, facilitating subsequent processing.

[0141] In the processing method of some embodiments, the step of shaping the stent includes: fixing the blank in the expanded state in a shaping mold; and performing an annealing shaping process on the blank fixed in the shaping mold.

[0142] The blank is shaped by a shaping mold to obtain a standardized valve stent 100, and the annealing shaping treatment is helpful to remove the stress of the valve stent 100 in the expanded state after completing the stent shaping step.

[0143] In the processing method of some embodiments, the annealing temperature of the annealing and shaping treatment is 500-550° C., the holding time is 2-30 minutes, and the cooling method is water cooling.

[0144] The above annealing temperature, holding time and cooling method can effectively remove the stress of the valve stent 100 in the expanded state within a reasonable time, while allowing the shape of the stent to maintain its final shape without rebound.

[0145] The third aspect of the present application further provides an artificial valve, including a valve stent 100, which is the valve stent 100 of the first aspect of the present application.

[0146] The artificial valve of the embodiment of the present application has the advantages of the valve stent 100 of the embodiment of the present application.

[0147] The artificial valve and valve stent 100 thereof, as well as the processing method of the artificial valve and valve stent thereof according to an embodiment of the present application are described in detail below with reference to FIG. 1 to FIG. 12 .

[0148] For ease of description, the angle formed by the straight rod segments B1 of two stent rods B of the quadrilateral grid that are opposite to each other along the circumference of the valve stent 100 gradually moving away from each other from the axial middle to the end of the quadrilateral grid is also called the straight rod segment cutting angle.

[0149] As shown in Figures 1 to 3, the artificial valve of the embodiment of the present application is a pulmonary valve. The artificial valve includes a valve stent 100, a valve 200 and a sealing membrane 300. The valve stent 100, the valve 200 and the sealing membrane 300 are sutured together by sutures 400. 201 in the figure is the valve edge. In the expanded state, the valve stent 100, close to the heart end grid 120 and the end grid 140 away from the heart end, gradually increases in diameter from the middle support grid 130 to the end away from the middle support grid 130, forming a dumbbell-shaped structure. The two stent rods B at the axial first end close to the heart end grid 120 and the end grid 140 away from the heart end are different in size from the two stent rods B at the axial second end.

[0150] The artificial valve also includes a connecting claw 101 provided on the valve stent 100. The connecting claw 1011 is connected to the corner of the grid 120 near the end near the heart, which is near the first axial end. The connecting claw 101 is used to fix the artificial valve when the artificial valve is inserted into the biological body. There is a connecting hole in the middle of the connecting claw 101. The connecting hole can be in a circular, square or triangular shape. One connecting claw 101 can be provided for every two grid structure units A, or one connecting claw 101 can be provided for every one grid structure unit A, or one connecting claw 101 can be connected to the grid 120 near the end of all grid structure units A.

[0151] In addition, a fixing groove 102 for installing a developing material is also provided on the valve support 100. The fixing groove 102 is provided on a middle supporting grid 130 of a grid structure unit A.

[0152] As shown in FIG. 4 to FIG. 9 , each grid structure unit A is symmetrically arranged relative to a plane passing through the axis of the valve stent 100 .

[0153] As shown in Figures 1 to 5 and 10, the grids 120 at the end proximal to the heart and the middle support grid 130 of each grid structure unit A are connected via a connecting rod 150. Along the circumference of the valve stent 100, every other grid structure unit A whose grids 140 at the end distal to the heart are not connected to its middle support grid 130 is provided with a grid structure unit A whose grids 140 at the end distal to the heart and the middle support grid 130 are connected via a connecting rod 150. As a result, the rigidity of the connection structure between the grids 120 at the end proximal to the heart and the middle support grid 130 of the valve stent 100 is greater than the rigidity of the connection structure between the grids 140 at the end distal to the heart and the middle support grid 130, giving the valve stent 100 a significant axially asymmetric structure at both ends.

[0154] The valve stent 100 is formed by laser cutting a seamless metal tube. The metal tube is, for example, a nickel-titanium alloy tube. The nickel-titanium alloy tube has good biocompatibility and mechanical properties and can withstand blood flow and heartbeat.

[0155] The outer diameter of the nickel-titanium alloy tube is, for example, 4.18 to 6.22 mm, the wall thickness is, for example, 0.30 to 0.52 mm, and the length is, for example, 88 to 2000 mm. The width W of the cut straight rod is generally 0.30 to 0.52 mm.

[0156] For example, in a specific example, the outer diameter of the nickel-titanium alloy tube is 4.2 mm, the wall thickness is 0.3 mm, the length is 1500 mm, and the width W of the cut straight rod is 0.31 mm.

[0157] The support rod B includes a straight rod section B1 and a connecting section B2. The connecting section B2 includes two arc connecting sections arranged at both ends of the straight rod section B1, and adjacent support rods B of the quadrilateral grid are connected by the arc connecting sections. The arc connecting section at one end of the support rod B close to the end of the quadrilateral grid is bent toward the inside of the quadrilateral grid. The arc connecting section at one end of the support rod B close to the middle of the quadrilateral grid is bent toward the outside of the quadrilateral grid. The straight rod section B1 is connected to the arc connecting section by an arc transition section. The arc transition section is bent in the opposite direction to the arc connecting section.

[0158] In the embodiments shown in Figures 4 to 9 , the quadrilateral grids of each grid structure unit A of the valve stent 100 are different. Each grid structure unit A includes a grid 120 near the heart end, a middle support grid 130, and a grid 140 far from the heart end, arranged in sequence from the first axial end to the second axial end.

[0159] As shown in FIG7 , L1 is the length between the centers of the arc connecting segments at both ends of the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 121 in FIG6 ) near the axial first end of the grid structure unit A near the end of the heart (to distinguish the support rods at different positions, the two support rods are also marked as 122 in FIG6 ) near the axial second end of the grid structure unit A near the end of the heart (to distinguish the support rods at different positions, the two support rods are also marked as 122 in FIG6 ) ; L3 is the length between the centers of the arc connecting segments at both ends of the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 131 in FIG6 ) near the axial first end of the axial middle support grid 130 of the grid structure unit A. Length; L4 is the length between the centers of the arc connecting segments at both ends of the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 132 in FIG6 ) supporting the grid 130 in the axial middle portion of the grid structure unit A near the axial second end; L5 is the length between the centers of the arc connecting segments at both ends of the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 141 in FIG6 ) near the axial first end of the grid 140 at the axial end of the grid structure unit A away from the heart; L6 is the length between the centers of the arc connecting segments at both ends of the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 142 in FIG6 ) near the axial second end of the grid 140 at the axial end of the grid structure unit A away from the heart.

[0160] As shown in FIG7 , α1 is the angle between the straight rod segments B1 of the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 121 in FIG6 ) that are opposite to each other along the circumference of the grid structure unit A near the first axial end of the grid 120 near the heart end; α2 is the angle between the straight rod segments B1 of the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 122 in FIG6 ) that are opposite to each other along the circumference of the grid structure unit A near the second axial end of the grid 120 near the heart end; α3 is the angle between the straight rod segments B1 of the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 131 in FIG6 ) that are opposite to each other along the circumference of the grid structure unit A near the first axial end of the middle support grid 130 ; α4 is the angle between the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 132 in FIG6 ) of the middle support grid 130 and are opposite to each other in the circumferential direction of the grid structure unit A near the second axial end; α5 is the angle between the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 141 in FIG6 ) of the straight rod segments B1 of the grid structure unit A near the first axial end away from the heart end grid 140 and are opposite to each other in the circumferential direction; α6 is the angle between the two support rods B (to distinguish the support rods at different positions, the two support rods are also marked as 142 in FIG6 ) of the straight rod segments B1 of the grid structure unit A near the second axial end near the heart end grid 120 and are opposite to each other in the circumferential direction.

[0161] In this embodiment, in each quadrilateral grid,

[0162] Among them, L i L is the length along the axial direction of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B close to the first axial end of the quadrilateral grid; j α is the length along the axial direction of the valve stent 100 between the centers of the arc transition sections at both ends of the stent rod B close to the second axial end of the quadrilateral grid; i is the included angle between the straight rod segments B1 of the two support rods B close to the first axial end of the quadrilateral grid; α j is the included angle between the straight rod segments B1 of the two support rods B close to the second axial end of the quadrilateral grid.

[0163] For example, in this embodiment, for the end grid 120 near the heart, i is 1 and j is 2; for the middle support grid 130, i is 3 and j is 4; and for the end grid 140 far from the heart, i is 5 and j is 6. Taking the middle support grid 130 as an example, if L3 = L4, then α3 = α4.

[0164] By simulating the possible fatigue failure of a valve stent 100 with an angle between the straight rod segments B1 of the circumferentially opposite stent rods B of the grid structure unit A during the molding process, the loading and release process of the valve stent 100 during implantation, and the repeated biomechanical stress, the following conclusions can be drawn from the results of finite element analysis:

[0165] When the aforementioned angle (straight rod segment cutting angle) of the straight rod segments B1 of the circumferentially opposite stent rods B of each quadrilateral grid of the grid structure unit A of the valve stent 100 is 12° or less, the stent rod B has a lower risk of fracture than other angles.

[0166] Table 1 lists the angles of some feasible examples of the valve stent 100 after cutting. The valve stent 100 has a stable overall structure, can meet clinical use requirements, and is safe and reliable during service in the patient's body.

[0167] Table 1 Angle of the valve stent example after cutting

[0168] Furthermore, during the finalization of the valve stent 100, there is a risk of fracture at the bend where adjacent grids 140 at the end of the valve stent 100, located away from the heart, are connected to adjacent grid structural units A. The risk of fracture during processing is lower when the straight rod segments of the grids 140 at the end of the valve stent 100, located away from the heart, are cut at an angle of 2.83° to 4.67°.

[0169] In the working diameter range of 4 to 8 mm of compression, the radial support stiffness of the stent gradually decreases as the cutting angle of the straight rod segment increases, indicating that the cutting angle of the straight rod segment should not be increased too much.

[0170] Fatigue analysis shows that fatigue fracture is a risk at both ends of the connection between adjacent grid structure units A, at the end grids 120 away from the heart, of the valve stent 100. The fatigue safety factor of the valve stent 100 increases with increasing straight rod cutting angles below 4.67°.

[0171] The cutting angle of the straight rod segment of the middle support grid 130 of the grid structure unit A of the valve stent 100 is in the range of 2.83° to 4.67°. The valve stent 100 has the best comprehensive performance in processing, loading and releasing, and avoiding fatigue failure.

[0172] As shown in FIG8 , in this embodiment, the inner radius of the arc connecting segments of each quadrilateral grid of the grid structure unit A can be the same. The inner radius R1 and the outer radius R2 of the arc connecting segment differ by a straight rod width W. The inner radius R1 of the arc connecting segment can be, for example, 0.49 mm.

[0173] In an embodiment not shown, the inner radii of the arc connecting segments of the quadrilateral grids of the grid structure unit A may be different.

[0174] As shown in FIG9 , the straight rod segment B1 is connected to the arc connecting segment through an arc transition segment, and the arc transition segment and the arc connecting segment have opposite bending directions.

[0175] In some embodiments of the valve stent 100, the inner radius of the arc transition section of each quadrilateral grid of the grid structure unit A can be the same. In Figure 9, the dimensions represent the following:

[0176] R 11 , R, R 91 The grid 120 near the end of the heart and the middle support body 51 The outer radius of the arc transition section of the two stent rods B close to the first axial end of the quadrilateral grid and the grid 140 far away from the heart end;

[0177] R 12 、R 52 、R 92 The inner radii of the arc transition sections of the two stent rods B close to the first axial end of the grid 120 near the heart end, the middle support body quadrilateral grid, and the grid 140 far from the heart end close to the first axial end are respectively;

[0178] R 21 、R 61 、R 101 The inner radii of the arc transition sections of the grid 120 near the heart end, the quadrilateral grid of the intermediate support body, and the grid 140 far from the heart end and the two stent rods B near the first axial end and the second axial end;

[0179] R 22 、R 62 、R 102 The outer radii of the arc transition sections of the grid 120 near the heart end, the quadrilateral grid of the intermediate support body, and the grid 140 far from the heart end and the two stent rods B near the first axial end and the second axial end;

[0180] R 31 、R 71 、R 111 The inner radii of the arc transition sections of the two stent rods B close to the first axial end and close to the second axial end of the grid 120 near the heart end, the middle support body quadrilateral grid, and the grid 140 far from the heart end are respectively;

[0181] R 32 、R 72 、R 112The outer radii of the arc transition sections of the two stent rods B close to the first axial end and close to the second axial end of the grid 120 near the heart end, the middle support body quadrilateral grid, and the grid 140 far from the heart end are respectively;

[0182] R 41 、R 81 、R 121 The inner radii of the arc transition sections of the two stent rods B close to the second axial ends of the grid 120 near the heart end, the middle support body quadrilateral grid, and the grid 140 far from the heart end close to the second axial ends are respectively;

[0183] R 42 、R 82 、R 122 They are respectively the inner radii of the arc transition sections of the grid 120 close to the heart end, the quadrilateral grid of the middle support body, and the grid 140 far from the heart end and close to the second axial end of the two support rods B.

[0184] The difference between the inner radius and the outer radius of the arc transition section is a straight rod width W. The inner radius of the arc transition section can be 3.86 mm, for example.

[0185] In an embodiment not shown in the figure, the dimensions marked in FIG9 may also be partially the same or different.

[0186] As shown in Figures 4 to 9 , in the valve stent 100 of this embodiment, the length along the axial direction of the valve stent 100 between the centers of the arcuate transition sections at both ends of the stent rod B near the first axial end of the grid 120 near the heart end is shorter than the length along the axial direction of the valve stent 100 between the centers of the arcuate transition sections at both ends of the stent rod B near the second axial end. The length along the axial direction of the valve stent 100 between the centers of the arcuate transition sections at both ends of the stent rod B near the first axial end of the grid 140 far from the heart end is longer than the length along the axial direction of the valve stent 100 between the centers of the arcuate transition sections at both ends of the stent rod B near the second axial end.

[0187] For example, the length between the centers of the arcuate transition sections at both ends of the stent rod B near the first axial end of the grid 120 near the heart end along the axial direction of the valve stent 100 is 10.20 mm. The length between the centers of the arcuate transition sections at both ends of the stent rod B near the second axial end of the grid 120 near the heart end along the axial direction of the valve stent 100 is 11.85 mm. The length between the centers of the arcuate transition sections at both ends of the stent rod B near the second axial end of the grid 140 away from the heart end along the axial direction of the valve stent 100 is 10.20 mm. The length between the centers of the arcuate transition sections at both ends of the stent rod B near the first axial end of the grid 140 away from the heart end along the axial direction of the valve stent 100 is 11.85 mm.

[0188] As shown in Figure 10, in this embodiment, in the expanded state, the outer diameter D2 of the axial first end (corresponding to the lower end of Figure 10) and the axial second end (corresponding to the upper end of Figure 10) of the valve stent 100 is larger than the outer diameter D1 of the axial middle part, thereby forming a dumbbell-shaped structure with the axial ends larger than the axial middle part.

[0189] As shown in Figures 10 and 11, in the expanded state, the valve stent 100 transitions from the axial middle to the axial first end through the first concave arc segment 1A and the first convex arc segment 1B in sequence, and transitions from the axial middle to the axial second end through the second concave arc segment 1C and the second convex arc segment 1D in sequence.

[0190] The cross section of the first concave arc segment 1A passing through the axis of the valve stent 100 has a radius of R A The first concave arc is concave toward the inner side of the valve stent 100; the cross section of the first convex arc segment 1B passing through the axis of the valve stent 100 is a radius R B The first convex arc protrudes toward the outside of the valve stent 100; the cross section of the second concave arc segment 1C passing through the axis of the valve stent 100 is a radius R C The second concave arc is concave toward the inner side of the valve stent 100; the cross section of the second convex arc segment 1D passing through the axis of the valve stent 100 is a radius R D A second convex arc protruding toward the outside of the valve stent 100.

[0191] R D and R B They can be equal, for example, they can be 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm.

[0192] R C and R A They can be equal, for example, 5mm, 7mm, 9mm, 10mm, 11mm, or 13mm.

[0193] The total height H1 of the valve stent 100 in the expanded state and the height H2 of the middle support grid 130 are shown in Table 2. The external dimensions of the valve stent 100 in the expanded state are shown in Table 2.

[0194] Table 2 Dimensions of the valve stent example in the expanded state

[0195] As shown in FIG12 , the processing method of the valve stent according to the embodiment of the present application includes:

[0196] The stent cutting step includes cutting the metal tube to form a blank in a cut state having the same structure as the valve stent 100, and making the two stent rods B of the quadrilateral grid of the blank that are opposite to each other along the circumference of the valve stent 100 gradually move away from each other from the axial middle of the quadrilateral grid to the end to form an angle. The angle between the straight rod segments B1 of each two stent rods B of the central support grid 130 that are opposite to each other along the circumference of the valve stent 100 is less than or equal to 12°. The blank in the cut state is formed by laser cutting. The power of the laser cutting machine is preferably capable of cutting through a single layer of nickel-titanium alloy tubing, and argon gas protection is used. The arc starting point is located in the middle of the straight rod segment B1. Since there is no stress concentration phenomenon in the middle of the straight rod segment B1, and the arc starting point generally cuts a larger circular spot and has dimensional deviation, locating the arc starting point in the middle of the straight rod segment B1 is beneficial to preventing the stent rod B from breaking.

[0197] The stent grinding step includes grinding the green body with corundum and purified water for 5 to 20 minutes. By grinding the valve stent 100, slag attached to the wall surface of the valve stent 100 can be removed.

[0198] The stent pre-forming step involves applying multiple pre-forming steps to the cut blank, followed by annealing after each pre-forming step, to form the blank in its expanded state. The multi-step pre-forming process consists of 2 to 6 steps. The maximum strain at each pre-forming step is less than 8%. The annealing temperature is 400-500°C, the holding time is 2-21 minutes, and the cooling method is water cooling.

[0199] The stent shaping step includes: securing the expanded blank in a shaping mold; and annealing the blank secured in the shaping mold. The annealing temperature for the annealing treatment is 500-550°C, the holding time is 2-30 minutes, and the cooling method is water cooling.

[0200] The stent sandblasting step includes sandblasting the valve stent 100 in the expanded state.

[0201] The stent polishing step includes polishing the valve stent 100 after sandblasting.

[0202] The stent cleaning step may include a stent rough cleaning step and a stent fine cleaning step. The stent rough cleaning step may be performed by, for example, rinsing with water, and the stent fine cleaning step may be performed by, for example, ultrasonic cleaning.

[0203] In the developing mark fixing step, the developing material is fixedly mounted on the fixing groove 102 .

[0204] As shown in FIG12 , this embodiment further provides a method for processing an artificial valve, comprising:

[0205] The pericardium pre-sizing step includes pericardium collection, pericardium rinsing, pericardium qualitative treatment, pericardium screening, etc. The pericardium is, for example, porcine pericardium.

[0206] Steps for making the leaflets and sealing membrane.

[0207] Pericardium biodeloading steps.

[0208] The valve suturing step includes suturing the valve leaflets and the sealing membrane to the aforementioned valve stent 100 to form an artificial valve.

[0209] The chemical treatment step is a key process in the processing of artificial valves, in order to treat the tissue to inhibit calcification after implantation. The glutaraldehyde solution is heated to a first temperature. The first temperature is, for example, 15 to 90°C. More preferably, the glutaraldehyde solution is heated to a first temperature of 55 to 75°C and maintained for 0.5 to 10 days. Then, before contacting the bioprosthetic tissue, the temperature of the glutaraldehyde solution is adjusted to a second temperature. The second temperature is, for example, 30 to 70°C, preferably 45 to 55°C, and the time range for treating the tissue is 0.1 to 15 days, and the more preferred time range is about 0.1 to 12 days. For example, at a temperature of about 50°C, the preferred treatment time is about 5 to 10 days, and the most preferred treatment time is about 7 days.

[0210] Fine washing step.

[0211] Sterilization step.

[0212] Those skilled in the art will understand that, in the above-mentioned method of a specific embodiment, the writing order of each step does not mean a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of each step should be determined by its function and possible internal logic.

[0213] The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced to each other and will not be repeated herein for the sake of brevity.

[0214] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them. Although the present application has been described in detail with reference to preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present application can still be modified or some technical features can be replaced by equivalents, which should all be included in the scope of the technical solutions requested for protection in this application.

Claims

1. A valve stent (100) is formed by cutting a metal pipe and has a cut state and a deployed state. The valve stent (100) includes a plurality of grid structure units (A) that are circumferentially distributed along the valve stent (100) and axially extend along the valve stent (100). The grid structure unit (A) includes a plurality of quadrilateral grids. The plurality of quadrilateral grids include at least one near-heart end grid (120), at least one middle support grid (130), and at least one far-heart end grid (140) that are sequentially arranged from the axial first end to the axial second end along the valve stent (100). Each quadrilateral grid includes four stent rods (B) that are sequentially connected end to end. The stent rod (B) includes a straight rod segment (B1) and a connecting segment (B2). The straight rod segment (B1) of each stent rod (B) forms the grid body of the quadrilateral grid, and the connecting segment (B2) of each stent rod (B) forms the corner of the quadrilateral grid. The adjacent stent rods (B) of each quadrilateral grid are connected through the connecting segment (B2), and the corners at the axial middle parts of the corresponding quadrilateral grids of adjacent grid structure units (A) are connected. In the cut state, the straight rod segments (B1) of the two stent rods (B) that are circumferentially opposite to each other along the valve stent (100) of each quadrilateral grid gradually move away from each other from the axial middle part of the quadrilateral grid to the ends to form an included angle, where, The included angle between the straight rod segments (B1) of every two of the support rods (B) that are circumferentially opposite to each other along the valve stent (100) of the middle support grid (130) is less than or equal to 12°.

2. The valve stent (100) according to claim 1, wherein the plurality of quadrilateral grids include two of the middle support grids (130), and the included angle between the straight rod segments (B1) of every two of the support rods (B) that are circumferentially opposite to each other along the valve stent (100) of each middle support grid (130) is less than 11.74°; or the plurality of quadrilateral grids include one of the middle support grids (130), and the included angle between the straight rod segments (B1) of every two of the support rods (B) that are circumferentially opposite to each other along the valve stent (100) of the middle support grid (130) is less than 6.14°.

3. The valve stent (100) according to claim 2, wherein the plurality of quadrilateral grids include two of the middle support grids (130), and the included angle between the straight rod segments (B1) of every two of the support rods (B) that are circumferentially opposite to each other along the valve stent (100) of each middle support grid (130) is 5.0° to 11.0°; or the plurality of quadrilateral grids include one of the middle support grids (130), and the included angle between the straight rod segments (B1) of every two of the support rods (B) that are circumferentially opposite to each other along the valve stent (100) of the middle support grid (130) is 2.5° to 5.5°.

4. The valve stent (100) according to any one of claims 1 to 3, wherein in the post-cut state, the included angle between the straight rod segments (B1) of two of the support rods (B) near the first axial end of the middle support grid (130) is equal to or different from the included angle between the straight rod segments (B1) of two of the support rods (B) near the second axial end.

5. The valve stent (100) according to any one of claims 1 to 4, wherein the connecting section (B2) of the support rod (B) includes two bent connecting sections provided at both ends of the straight rod segment (B1), and adjacent support rods (B) of the quadrilateral grid are connected by the bent connecting sections; the bent connecting section at one end of the support rod (B) near the end of the quadrilateral grid where it is located bends towards the inside of the quadrilateral grid; the bent connecting section at one end of the support rod (B) near the middle of the quadrilateral grid where it is located bends towards the outside of the quadrilateral grid.

6. The valve stent (100) according to claim 5, wherein the bent connecting section is an arc connecting section, and the ratio range of the length of the straight rod segment to the inner radius of the arc connecting section is between 4 and 30.

7. The valve stent (100) according to claim 5 or 6, wherein the straight rod segment (B1) is connected to the bent connecting section through a bent transition section (B3), and the bent transition section (B3) has a bending direction opposite to that of the bent connecting section.

8. The valve stent (100) according to claim 7, wherein the curved transition section (B3) is an arc transition section, and the ratio of the inner radius of the arc transition section to the length of the straight rod section ranges between 0.25 and 0.

75.

9. The valve stent (100) according to any one of claims 5 to 8, wherein the curved connection section is an arc connection section; wherein, the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial first end of the near-heart end grid (120) is equal to or different from the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial second end; and / or the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial first end of the far-heart end grid (140) is equal to or different from the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial second end; and / or the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial first end of the middle support grid (130) is equal to or different from the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial second end.

10. The valve stent (100) according to claim 9, wherein the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial first end of the near-heart end grid (120) is less than the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial second end; and / or the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial first end of the far-heart end grid (140) is greater than the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial second end.

11. The valve stent (100) according to claim 9 or 10, wherein the ratio of the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial first end of the near-heart end grid (120) to the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the stent rod (B) near the axial second end is 0.65 to 1.00; and / or The length along the axis of the valve stent (100) between the centers of the arc transition segments at both ends of the stent struts (B) of the grid (140) at the end far from the heart near the axial second end and the length along the axis of the valve stent (100) between the centers of the arc transition segments at both ends of the stent struts (B) of the grid near the axial first end is in the ratio of 0.65 to 1.

00.

12. The valve stent (100) according to any one of claims 5 to 11, wherein the bent connection segment is an arc connection segment; the plurality of quadrilateral grids include a grid (120) near the heart end, a middle support grid (130), and a grid (140) far from the heart end, which are sequentially arranged along the axis of the valve stent (100) from the axial first end to the axial second end; the length range along the axis of the valve stent (100) between the centers of the arc transition segments at both ends of the stent struts (B) of the middle support grid (130) is 3.05 to 8.22 mm; and / or the length range along the axis of the valve stent (100) between the centers of the arc transition segments at both ends of the stent struts (B) of the grid (120) near the heart end is 3.55 to 12.50 mm; and / or the length range along the axis of the valve stent (100) between the centers of the arc transition segments at both ends of the stent struts (B) of the grid (140) far from the heart end is 3.55 to 12.50 mm.

13. The valve stent (100) according to any one of claims 5 to 12, wherein the bent connection segment is an arc connection segment; In each of the grid structure units (A), wherein, L i is the length along the axis of the valve stent (100) between the centers of the arc transition segments at both ends of the support rod (B) near the first axial end of the quadrilateral mesh; L j is the length along the axis of the valve stent (100) between the centers of the arc transition sections at both ends of the support rod (B) near the second axial end of the quadrilateral mesh; α i is the included angle of the straight rod segments (B1) of the two said support rods (B) near the first axial end of the said quadrilateral grid; α j is the included angle of the straight rod segments (B1) of the two support rods (B) of the quadrilateral grid near the second axial end.

14. The valve stent (100) according to any one of claims 1 to 13, wherein the valve stent (100) further includes a plurality of connecting rods (150), wherein the grid (120) near the heart end and the middle support grid (130) of each grid structure unit (A) are connected by one connecting rod (150), or along the circumferential direction of the valve stent (100), one grid structure unit (A) whose grid (120) near the heart end is connected to the middle support grid (130) by one connecting rod (150) is provided every one or two grid structure units (A) whose grid (120) near the heart end is not connected to the middle support grid (130); and / or the grid (140) far from the heart end and the middle support grid (130) of each grid structure unit (A) are connected by one connecting rod (150), or along the circumferential direction of the valve stent (100), one grid structure unit (A) whose grid (140) far from the heart end is connected to the middle support grid (130) by one connecting rod (150) is provided every one or two grid structure units (A) whose grid (140) far from the heart end is not connected to the middle support grid (130).

15. The valve stent (100) according to any one of claims 1 to 14, wherein in the deployed state, the outer diameter D2 of the axially first end and the axially second end of the valve stent (100) is greater than the outer diameter D1 of the axially middle part.

16. The valve stent (100) according to claim 15, wherein in the deployed state, the range of the outer diameter D1 of the axially middle part of the valve stent (100) is 18.0 - 32.0 mm, and the range of the outer diameter D2 of the axially first end and the axially second end of the valve stent (100) is 20.0 - 54.0 mm.

17. The valve stent (100) according to claim 15 or 16, wherein in the deployed state, the total height H1 of the valve stent (100) is 30.0 - 60.0 mm, and the height H2 of the middle support grid (130) is 12.0 - 30.0 mm.

18. The valve stent (100) according to any one of claims 15 to 17, wherein in the deployed state, the valve stent (100) transitions from the axial middle part to the axial first end through a first inner concave arc segment (1A) and a first outer convex arc segment (1B) in sequence, and transitions from the axial middle part to the axial second end through a second inner concave arc segment (1C) and a second outer convex arc segment (1D) in sequence; wherein, The cross-section of the first concave arc segment (1A) passing through the axis of the valve stent (100) is a first concave arc with a radius of R A that is concave inward towards the inside of the valve stent (100); the cross-section of the first convex arc segment (1B) passing through the axis of the valve stent (100) is a first convex arc with a radius of R B that is convex outward towards the outside of the valve stent (100); the cross-section of the second concave arc segment (1C) passing through the axis of the valve stent (100) is a second concave arc with a radius of R C that is concave inward towards the inside of the valve stent (100); the cross-section of the second convex arc segment (1D) passing through the axis of the valve stent (100) is a second convex arc with a radius of R D that is convex outward towards the outside of the valve stent (100); where R A and R C range from 3.0 to 15.0 mm, and R B and R D range from 3.0 to 15.0 mm.

19. A processing method for the valve stent according to any one of claims 1 to 18, comprising: A stent cutting step, including cutting a metal pipe to form a blank in a post - cutting state having the same structure as the valve stent (100), and making the two stent rods (B) opposite to each other in the circumferential direction of the quadrilateral grid of the blank gradually move away from each other from the axially middle part to the ends of the quadrilateral grid to form an included angle, wherein the included angle of the straight rod segments (B1) of each two stent rods (B) opposite to each other in the circumferential direction of the middle support grid (130) is less than or equal to 12°; A stent pre - shaping step, including performing multi - step pre - shaping on the blank in the post - cutting state and annealing during each step of pre - shaping to form a blank in the deployed state; and A stent shaping step, shaping the blank in the deployed state after stent pre - shaping through a shaping die to form the valve stent (100) in the deployed state.

20. The processing method for the valve stent according to claim 19, wherein In the step of pre-shaping the bracket, the multi-step pre-shaping is 2 to 6 steps of shaping; and / or, the maximum strain of each step of pre-shaping is less than 12%; and / or, the annealing temperature of the annealing treatment is 400 to 500 °C, the heat preservation time is 2 to 21 min, and the cooling method is water cooling; and / or the stent shaping step includes: Fixing the blank in the deployed state in the shaping die; Performing annealing and shaping treatment on the blank fixed in the shaping die, wherein the annealing temperature of the annealing and shaping treatment is 500 - 550 °C, the heat preservation time is 2 - 30 min, and the cooling method is water cooling.

21. An artificial valve, comprising a valve stent (100), wherein the valve stent (100) is the valve stent (100) according to any one of claims 1 to 18.

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