CN114073603A

CN114073603A - Valve support and artificial heart valve

Info

Publication number: CN114073603A
Application number: CN202010844950.8A
Authority: CN
Inventors: 赖柳山; 陈文俊; 郑伟城
Original assignee: Lifetech Scientific Shenzhen Co Ltd
Current assignee: Shenzhen Jianxin Medical Technology Co ltd
Priority date: 2020-08-20
Filing date: 2020-08-20
Publication date: 2022-02-22
Anticipated expiration: 2040-08-20
Also published as: CN114073603B; WO2022037242A1

Abstract

The invention belongs to the technical field of medical instruments, and particularly relates to a valve stent and a prosthetic heart valve. The valve support is of a tubular structure and comprises a support section, a transition section and valve leaflet sections, wherein the transition section is used for connecting the support section and the valve leaflet sections, the maximum diameter of the valve leaflet sections is smaller than the maximum diameter of the transition section, and the maximum diameter of the transition section is smaller than or equal to the maximum diameter of the support section, the transition section comprises a plurality of connecting rods, and the connecting rods form at least one open structure unit on the transition section, so that the problems of incomplete closing and excessive central regurgitation easily caused by the influence of the target position form on the opening and closing effect of the valve leaflets when the support is implanted into a target position are prevented.

Description

Valve support and artificial heart valve

Technical Field

The invention belongs to the technical field of medical instruments, and particularly relates to a valve stent and a prosthetic heart valve.

Background

The human heart primarily functions to power the blood within the human body. The heart can be classified anatomically as: the right atrium, right ventricle, left atrium, and left ventricle. Blood flows from the superior and inferior vena cava into the right atrium, then through the tricuspid valve into the right ventricle, where it flows through the pulmonary valve into the lungs under the contraction of the right ventricle. The blood flows into the left atrium after oxygen is obtained by lung exchange, then flows into the left ventricle through the mitral valve, and flows into each part of the human body through the aortic valve under the contraction action of the left ventricle. The human heart contains a total of four valves, the tricuspid, pulmonary, mitral, and aortic valves. The tricuspid valve is located between the right atrium and right ventricle; the mitral valve is located between the left atrium and the left ventricle. Naturally occurring normal valves typically have two or three leaflets, the roots of which are fixed to the annulus; the free edges of the leaflets have no other structure or are connected with chordae tendineae, the other ends of which are connected to papillary muscles on the myocardial wall. The valve functions to restrict the direction of blood flow, allowing blood flow from the inflow end to the outflow end of the valve when the leaflets are open, and preventing blood flow from the outflow end to the inflow end of the valve when the leaflets are closed. The four valves are positioned at the entrances and exits of the ventricles, when the ventricles relax, the tricuspid valve and the mitral valve are opened, the pulmonary valve and the aortic valve are closed, and blood flows into the ventricles from the atria; when the ventricles contract, the tricuspid and mitral valves close, the pulmonary and aortic valves open, and blood flows from the ventricles into the arteries. Therefore, whether the valve is normally opened or closed directly influences whether the heart function of the human body can normally provide power for blood.

Currently, heart valve diseases become one of the common cardiovascular diseases, and the pathological changes mainly include valvular insufficiency, which can be divided into two types according to the etiology: the first is organic, which is caused by organic lesions of valve leaflets, and the causes of the organic lesions mainly include congenital malformation or defect of the valve, rheumatic valvular disease, calcification and the like; the second category is functional, and the valve itself has no organic lesions, mainly due to atrial enlargement, high pressure and other indirect causes, such as annulus, papillary muscle, chordae tendineae, myocardial wall and other spatial abnormalities. In recent years, with the continuous improvement of interventional devices and the accumulation of related experience, interventional heart valve stents are applied to cases which are not suitable for surgical operations, such as aortic valves, pulmonary valves, mitral valves, tricuspid valves and the like, the number of completed cases is rapidly increasing, a plurality of clinical trials are being tightened, and the results of the trials provide more evidence-based medical evidence for the application of the technology.

However, there are some problems and deficiencies with current interventional prosthetic heart valve designs in clinical use and design phase. For example, in the existing valve, the valve leaflets are fixed on the support section of the valve support, the valve function is affected by the shape of the support section of the valve support after implantation, if the cross section of the implantation part is elliptical, the working condition of the valve leaflets is greatly different from the circular shape of the cross section of the valve support during design, the opening and closing effects of the valve leaflets are affected, and the phenomena of incomplete closure and excessive central regurgitation are easy to occur.

Disclosure of Invention

The invention aims to at least solve the problems that when the stent is implanted into a target position, the opening and closing effect of valve leaflets is influenced by the shape of the target position, so that the valve leaflets are easy to be insufficiently closed and the central regurgitation is excessive.

The invention provides a valve support which is of a tubular structure, and comprises a support section, a transition section and a valve leaflet section, wherein the transition section is used for connecting the support section and the valve leaflet section, the valve leaflet section is used for arranging valve leaflets, the support section is used for supporting the valve support, the maximum diameter size of the valve leaflet section is smaller than the maximum diameter size of the transition section, and the maximum diameter size of the transition section is smaller than or equal to the maximum diameter size of the support section, wherein the transition section comprises a plurality of connecting rods, and the connecting rods form at least one open structural unit on the transition section.

According to the valve support, the support section, the transition section and the valve leaf section are arranged, the valve leaf section is provided with the valve leaf and is used for supporting the whole valve support, the maximum diameter of the transition section is smaller than or equal to the maximum diameter of the support section, so that the support section can be supported at a target position for fitting, the maximum diameter of the valve leaf section is smaller than the maximum diameter of the transition section, when the transition section is fitted at the target position, the valve leaf section provided with the valve leaf does not need to be completely fitted at the target position, and therefore the valve leaf section provided with the valve leaf is not easily affected by the form of the target position, and the problems of incomplete closing and excessive central regurgitation occur. And the transition section is used for connecting the support section and the valve leaflet section, the transition section comprises a plurality of connecting rods, the connecting rods form an open structure unit on the transition section, the radial rigidity of the transition section is reduced, the support section and the valve leaflet section which are connected to two ends of the transition section can not be influenced mutually, so that the radial force transmission from the support section to the valve leaflet section is favorably blocked, the valve leaflet section or the support section can be completely released firstly in the releasing process, the other section is kept in the conveying sheath, the most appropriate state can be selected for releasing in the using process, and the operation difficulty is reduced.

In addition, the valve stent according to the present invention may have the following additional technical features:

in some embodiments of the invention, the radial stiffness of the transition section is less than the smallest of the radial stiffness of the support section and the radial stiffness of the leaflet section.

In some embodiments of the invention, the open structural unit comprises a first link and a second link, one end of the first link being connected to one end of the second link forming a transition section connecting node, the other end of the first link being connected to the leaflet section, the other end of the second link being connected to the support section.

In some embodiments of the invention, the strut section comprises a plurality of struts connected to one another to form strut section connection points, and the number of transition section connection nodes is less than the number of strut section connection points.

In some embodiments of the present invention, the open structural unit includes a plurality of third links disposed at intervals in a circumferential direction of the transition section, one end of the third link being connected to the leaflet section, and the other end of the third link being connected to the support section.

In some embodiments of the invention, a projection of the third link on a plane passing through the central axis of the valve stent intersects and forms an angle with the central axis of the valve stent.

In some embodiments of the invention, a projection of the third link on a plane through the central axis of the valve stent is parallel to or coincides with the central axis of the valve stent.

In some embodiments of the present invention, a projection of the third link on a plane tangential to the transition section surface is any one of a straight line shape, an arc line shape, or a broken line shape, or a combination of at least two of the straight line shape, the arc line shape, or the broken line shape.

In some embodiments of the invention, the transition section is removably connected to the support section and/or the transition section is removably connected to the leaflet section.

Another aspect of the present invention also provides a prosthetic heart valve having the valve stent of any one of the above, further comprising:

the flow blocking film is arranged on the valve leaflet section and the transition section;

the leaflet structure comprises a plurality of leaflets, wherein each leaflet comprises a fixed edge and a free edge, the fixed edges are fixedly connected with leaflet sections, and the free edges are opened and closed at an angle.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like parts are designated by like reference numerals throughout the drawings. Wherein:

FIG. 1 is a schematic structural view of a prosthetic heart valve according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of the valve stent of FIG. 1;

fig. 3 is a schematic structural view of the leaflet segment of fig. 1;

FIG. 4 is a schematic view of the tile-like structural unit of FIG. 3 in an expanded state;

FIG. 5 is a schematic view of the tile-shaped structural unit of FIG. 3 in a contracted state;

FIG. 6 is a schematic structural view of the support section of FIG. 1;

FIG. 7 is a schematic structural view of the transition section of FIG. 1;

fig. 8 is a schematic structural view of the leaflet of fig. 1;

FIG. 9 is a partial schematic structural view of a valve stent according to another embodiment of the present invention;

FIG. 10 is a schematic view of a portion of a third link according to another embodiment of the present invention;

FIG. 11 is a partial schematic view of a third link according to another embodiment of the present invention;

FIG. 12 is a partial schematic view of a third link according to another embodiment of the present invention;

FIG. 13 is a schematic view of a portion of a third link according to another embodiment of the present invention;

FIG. 14 is a partial schematic view of a third link according to another embodiment of the present invention;

FIG. 15 is a partial schematic structural view of a valve stent according to another embodiment of the present invention;

FIG. 16 is a schematic view of a portion of the third link of FIG. 15;

fig. 17 is an enlarged schematic view of a portion a in fig. 16.

The reference numerals in the drawings denote the following:

1000: a prosthetic heart valve;

100: a valve stent;

o: central axis of valve stent

10: support section, 11: a support bar;

20: leaflet segment, 21: tile-like structural unit, 211: v-shaped link, 212: straight rod, 22: a connecting rod;

30: transition section, 31: first link, 32: second link, 33: a third link;

40: a valve leaf frame;

50: a connecting portion;

60: a retaining ring;

200: leaflet, 210: fixed edge, 220: free edge, 230: a lobe angle;

a: first endpoint, B: support section connection point, C: the transition section is connected with the node.

300: flow-blocking film, 301: first flow blocking film, 302: second flow-resisting film

Detailed Description

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only, and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order described or illustrated, unless specifically identified as an order of performance. It should also be understood that additional or alternative steps may be used.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

For convenience of description, spatially relative terms, such as "inner", "outer", "lower", "below", "upper", "above", and the like, may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "over" the other elements or features. Thus, the example term "below … …" can include both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

For ease of description, the following description uses the terms "proximal" and "distal", where "proximal" refers to the end proximal to the operator and "distal" refers to the end distal from the operator, the phrase "axial direction" in the present disclosure refers to the direction in which the present device is advanced and pushed out, and the phrase "circumferential direction" in the present disclosure refers to the direction about the axial direction.

In the present embodiment, "open structural unit" means a unit that forms an unclosed structure on the transition section.

As shown in fig. 1, the present invention provides a prosthetic heart valve 1000, and the prosthetic heart valve 100 of the present embodiment includes a valve stent 100, a plurality of leaflets 200, and a flow blocking film 300. The anti-blocking film 300 covers a portion of the structure of the valve stent 100, and the anti-blocking film 300 mainly functions to fix the valve leaflets 200 and prevent blood from passing through the regions other than the channels formed between the valve leaflets 200. The material of the flow-blocking film 300 is preferably a polymer material, such as PET (poly-p-phthalic acid), PTFE (polytetrafluoroethylene), PU (polyurethane), etc., and can also be a biological tissue material and a tissue engineering material. The leaflets 200 function primarily as one-way valves, allowing blood to flow from one end of the prosthetic heart valve to the other, while preventing backflow of blood from the other end to the one end. The valve leaflet 200 is preferably made of biological tissue material, such as porcine pericardium, bovine pericardium, equine pericardium, ovine pericardium, porcine heart valve, etc., or polymer material and tissue engineering material.

The valve stent 100 of the present embodiment is a tubular structure that can be switched between a contracted state and an expanded state, and fig. 2 shows the expanded state of the valve stent 100. The valve stent 100 comprises a support section 10, a transition section 30 and a valve leaflet section 20 which are arranged in sequence. The support section 10 is a tubular structure in an expanded state, and is used for being in interference fit with a target position of human tissue after being implanted and generating radial support force, so as to play a role in fixing the prosthetic heart valve 1000. The leaflet segment 20 is used to secure the leaflet 200. The transition section 30 is used for receiving the leaflet section 20 and the support section 10, so that the support section 10 and the leaflet section 20 connected to the two ends of the transition section 30 can not be affected by each other, thereby being beneficial to blocking the radial force transmission from the support section 10 to the leaflet section 20.

The maximum diameter of the leaflet segment 20 of the present embodiment is smaller than the maximum diameter of the support segment 10, preferably 10% to 20% smaller, and the support segment 10 does not need to be completely attached to the target position after the interference fit generates the support force at the target position, so that the leaflet segment 20 provided with the leaflet 200 is not easily affected by the shape of the target position, and the leaflet segment 20 can maintain the original shape, thereby avoiding the problems of incomplete closure and excessive regurgitation at the center.

Referring again to fig. 1, the flow-blocking membrane 300 includes a first flow-blocking membrane 301 and a second flow-blocking membrane 302, the first flow-blocking membrane 301 and the second flow-blocking membrane 302 being spliced together, wherein the first flow-blocking membrane 301 is disposed at the leaflet segment 20 and the second flow-blocking membrane 302 is disposed at the transition segment 30. The maximum diameter dimension of the leaflet segment 20 is less than the maximum diameter dimension of the transition segment 30, and thus, the second flow barrier membrane 302 disposed at the transition segment 30 is effective in preventing blood from penetrating even if the leaflet segment 20 does not fully conform to the target location, as long as the transition segment 30 is ensured to fully conform to the target location.

The flow blocking film 300 of the present embodiment is fixedly attached to the valve stent 100 by a suture, for example, disposed on the inner surface or the outer surface of the valve stent 100, the flow blocking film 300 covers the leaflet section 20 and the transition section 30 of the valve stent 100, and the flow blocking film mainly functions to fix the leaflets 200 and prevent blood from flowing from the area outside the channel formed by the free edges 220 of the leaflets 200. Wherein the first flow blocking film 301 of the leaflet segment 20 can be made of a cylindrical fabric having the same size as the shape of the inner surface of the valve stent 100 after expansion, and the contour of the end of the first flow blocking film 301 that is not connected to the second flow blocking film 302 can be trimmed or made flat according to the edge shape of the fixed edge of the valve stent 100 or the leaflet 200. The second flow-blocking film 302 of the transition section 30 can be directly sewn by tubular cloth with the same size as the expanded transition section 30 structure, or can be formed by splicing and sewing a plurality of small pieces with sector structures, and the second flow-blocking film 302 of the transition section 30 can more effectively prevent peripheral leakage. The suture of the flow blocking film 300 is performed in the natural state of the expanded valve stent 100, and the surface of the flow blocking film 300 is kept tight without affecting the shape of the valve stent 100. The material of the first flow barrier film 301 of the leaflet segment 20 and the second flow barrier film 302 of the transition segment 30 may be different or the same. The material of the suture is preferably a high polymer material, such as PET, PTFE, PU and the like.

Referring to fig. 3, the leaflet segment 20 is a tubular structure composed of a plurality of tile-shaped structural units 21, and the axial length between any two points on the tile-shaped structural units 21 that are axially collinear remains unchanged during the switching process between the contracted state and the expanded state of the valve stent 100.

By designing the leaflet segment 20 into a tubular structure composed of a plurality of tile-shaped structural units 21, and in the switching process of the contraction state and the expansion state of the valve stent 100, the axial length between any two points which are axially collinear on the tile-shaped structural units 21 is kept unchanged, so that the leaflet 200 and the obstructing film 300 fixed on the leaflet segment 20 are favorably prevented from being subjected to axial tension due to axial deformation of the valve stent 100 in the sheathing contraction process, and the problem that the valve stent 100 leaks due to tearing of the obstructing film and the leaflet 200 is effectively prevented.

As shown in fig. 3 to 5, the plurality of tile-shaped structural units 21 of the leaflet segment 20 in the present embodiment are sequentially arranged in the circumferential direction and the axial direction of the leaflet segment 20. The tile-shaped structural unit 21 includes two V-shaped links 211 and two straight rods 212. The two V-shaped links 211 are disposed at intervals along the axial direction of the leaflet section 20, and the opening directions of the two V-shaped links 211 coincide. The two straight rods 212 are arranged at intervals along the circumferential direction of the leaflet section 20, and the two V-shaped links 211 are connected by the two straight rods 212. The V-shaped link 211 is formed by connecting two curved rods, and a first end point a is formed at the joint of the two curved rods. Two ends of each V-shaped connecting rod 211 are fixed on adjacent straight rods 212 which are uniformly distributed in the circumferential direction, the number of the straight rods 212 is integral multiple of the number of the valve leaflets 200, and the straight rods 212 are preferably 12, so that the valve leaflets 200 are effectively supported, and the deformation consistency of all positions in the circumferential direction is kept in the process that the valve leaflet sections 20 are extruded and deformed. In the axial direction, the V-shaped connecting rods 211 distributed in the circumferential direction are arranged in an equidistant array, the number of the arrays is greater than or equal to 2, the distance between the arrays is greater than the distance between two end points on the curved rod, that is, the length of the straight rod 212 is greater than the maximum length of the V-shaped connecting rods 211 in the axial direction of the leaflet segment 20, preferably, the number of the arrays is 3, so that in the process that the leaflet segment 20 is extruded and deformed, the V-shaped connecting rods 211 have enough deformation space in the axial direction, and the two V-shaped connecting rods 211 adjacently arranged in the axial direction are prevented from being extruded with each other, so that the tearing of the flow blocking film and the leaflet 200 is caused, and the problem of leakage of the valve support 100 is caused.

Referring to fig. 4 and 5, when the tile-shaped structural unit 21 is switched between the contracted state and the expanded state, the straight rod 212 is not deformed during the switching process, and the axial vertical state is still maintained. The V-shaped links 211 deform, and because the structures of the two V-shaped links 211 are consistent, the two V-shaped links 211 always deform synchronously during the state switching process of the tile-shaped structure unit 21, and the axial distance between the two V-shaped links 211 always remains consistent, thereby ensuring that the distance between any two points which are axially collinear in the tile-shaped structure unit 21 remains unchanged during the switching between the expanded state and the contracted state of the valve stent 100.

As further shown in fig. 3, in some embodiments of the invention, the leaflet segment 20 further comprises a leaflet frame 40. The leaflet frame 40 is disposed at one end of the leaflet segment 20 that is not connected to the transition section 30, specifically, the leaflet frame 40 is disposed on the straight rod 212 at equal intervals, and in the present embodiment, the leaflet frame 40 is disposed on the straight rod 212 at equal intervals that is equal to the number of leaflets 200, and the leaflet frame is used for fixing the angle of the leaflets 200. The inside of the leaflet frame 40 is provided with a rectangular hollow structure for fixing the angle of the leaflet 200. The valve stent 100 of the present embodiment further includes a connection portion 50, the connection portion 50 being connected to an end of the leaflet frame 40, the leaflet frame 40 being disposed between the connection portion 50 and the straight rod 212. The connecting part 50 is of a T-shaped structure, and the connecting part 50 is used for connecting the valve stent 100 and the conveyor during the conveying process.

As shown in fig. 6, the support section 10 of the present embodiment has a tubular structure as a whole in an expanded state, and includes a plurality of support rods 11, and the plurality of support rods 11 are connected to each other by a support section connection point B to form a circumferential closed shape. Each support rod 11 is connected end to end through a support section connection point B to form a rhombic structure unit, the rhombic structure units are uniformly distributed in an array manner around the axis of the support section 10 in the circumferential direction, and the preferred array number is an integral multiple of the number of straight rods 212 of the leaflet section 20. Then the second, third and even more layers in the axial direction are designed by the honeycomb structure. In this embodiment, it is preferable that the support section 10 has two diamond-shaped structural units in total, considering that the overall length of the valve stent 100 is not too long. The use of diamond-shaped structural elements for the support sections 10 ensures that sufficient radial support is provided when compressed to a smaller diameter.

As further shown in FIG. 7, the transition section 30 is generally tubular in configuration with a large proximal end and a small distal end in the expanded configuration. The transition section 30 comprises a plurality of first links 31 and a plurality of second links 32, one end of each first link 31 is connected with one end of each second link 32 to form a transition section connection node C, the other end of each first link 31 is connected with the leaflet section 20, the other end of each second link 32 is connected with the support section 10, at least one open structure unit 303 is formed on the transition section 30, and the open structure units 303 are circumferentially arranged to form the transition section 30. In the present embodiment, the two first links 31 and the two second links 32 form an "X" shaped open structure unit 303, the length of the first link 31 is greater than that of the second link 32, and the length of the second link 32 is substantially equal to that of the support rod 11, so that the distance between any two adjacent first links 31 in the circumferential direction is greater than that between any two adjacent second links 32 in the circumferential direction, thereby ensuring that the transition section 30 has good compressibility. Meanwhile, the number of the transition section connecting nodes C is smaller than the number of the supporting section connecting points B in the same circumferential direction on the supporting section 10, and the number of the supporting section connecting points B is an integral multiple of the number of the transition section connecting nodes C. The reduction in the number of endpoints in the circumferential direction on the transition section 30 can reduce the radial stiffness of the valve stent 100, and can effectively block the support section 10 from transmitting radial forces to the leaflet sections 20.

As shown in fig. 1 and fig. 3, the proximal end of the leaflet segment 20 of the present embodiment is further provided with a connecting rod 22 disposed along the axial direction, the connecting rod 22 is disposed between two adjacent tile-shaped structural units 21, one end of the first connecting rod 31 is connected to the proximal end of the leaflet segment 20 through the connecting rod 22, the other end of the first connecting rod 31 is connected to one end of the second connecting rod 32 through the transition section connecting node C, and the other end of the second connecting rod 32 is connected to the distal end of the support section 10 through the support section connecting point B. The transition section 30 is provided with the open structure unit 303, so that the transition section does not form a unit of a closed structure, the transition section 30 has weaker radial rigidity, the support section 10 and the valve leaflet section 20 connected to two ends of the transition section 30 can be not influenced mutually, and the radial force transmission from the support section 10 to the valve leaflet section 20 is favorably blocked, so that the valve leaflet section 20 or the support section 10 can be completely released firstly in the releasing process, the other section is reserved in the conveying sheath, the most suitable state is favorably selected to be released in the using process, and the operation difficulty is reduced. The valve stent 100 is formed by laser cutting of an alloy pipe, the material is preferably super-elastic nickel-titanium alloy and stainless steel material, and the required design shape, size and surface quality are achieved through heat treatment, expansion and shaping and surface treatment.

By separately arranging the leaflet segment 20 and the support segment 10 on the valve support 100 and arranging the transition segment 30 with a buffering effect between the leaflet segment 20 and the support segment 10, the radial force transmitted from the support segment 10 to the leaflet segment 30 in the contraction and deformation process of the valve support 100 can be effectively reduced, so as to realize the ideal working state of retaining the circular section of the leaflet 200 to a greater extent. Meanwhile, the transition section 30 of the valve stent 100 adopts a structure (open structure unit) with lower rigidity, and in the release process of the valve stent 100, the leaflet section 20 or the support section 10 can be completely released firstly, and the other section is kept in the delivery sheath, so that the most appropriate state can be selected for release in the use process, and the operation difficulty is reduced.

As shown in fig. 1 and 8, the artificial heart valve 1000 of the present embodiment has 3 leaflets 200, and the leaflets 200 have the same structure and shape, are connected end to end by the valve angle 230, and are uniformly distributed inside the valve stent 100. The leaflet 200 includes a fixed edge 210 and a free edge 220, wherein the fixed edge 210 is fixed on the flow blocking membrane of the leaflet segment 20 by a suture, and the free edge 220 is not restricted and can be opened and closed angularly. The corners 230 are threaded out of the leaflet frame 40 of the leaflet segment 20, then folded back around the stems on the leaflet frame 40 to conform to the leaflets 200 within the valve stent 100 and secured with sutures.

In other embodiments of the invention, the transition section 30 of the valve stent 100 is different in structure from the above-described embodiments. As shown in fig. 9, in this embodiment, the transition section 30 is composed of a plurality of third links 33 arranged at intervals in the circumferential direction, and the third links 33 may be simple straight rods. The distal end of the third link 33 is connected to the first end point a of the proximal end of the leaflet segment 20 and the proximal end of the third link 33 is connected to the support segment connection point B of the distal end of the support segment 10. The projection of the third link 33 on a plane through the central axis O of the valve stent is parallel to or coincides with the central axis O of the valve stent.

In the above embodiment, the third link 33 replaces the first link 31 and the second link 32, and the existence of the transition section connection node C on the transition section 30 is eliminated, so that the radial stiffness of the transition section 30 is reduced, and the radial force transmission from the support section 10 to the leaflet section 20 is blocked. It will be appreciated that the open structural element comprises a third link 33, the arrangement of the third link 33 on the transition section 30 forming an open structural element on the transition section 30.

In other embodiments of the present application, the structure of the third link 33 may also be modified. The projection of the third connecting rod 33 on the plane tangent to the surface of the transition section 30 is any one of a straight line shape, an arc line shape or a fold line shape, or a combination of at least two of the straight line shape, the arc line shape or the fold line shape. As shown in fig. 10 to 14, the projection of the third link 33 on a plane tangential to the surface of the transition section 30 may be any one of an arc segment, an angled multi-rod segment, a curved segment with wave circles, a bent rod segment with a plurality of S-shaped bends, or a multi-rod segment with a dash shape. Through setting up various bending structures on third connecting rod 33, can make third connecting rod 33 equal effect increase an elastic component in the axial, reduced third connecting rod 33 self rigidity to reduce the radial rigidity of changeover portion 30, and then be favorable to obstructing support section 10 to the transmission radial force of leaflet section 20.

As further shown in fig. 15, in other embodiments of the present application, the projection of the third link 33 on the plane of the central axis O of the valve stent intersects and forms an angle with the central axis O of the valve stent, i.e. the third link 33 is arranged obliquely in the axial direction. By arranging the third link 33 to be inclined in the axial direction, the pressure of the valve stent 100 can be relieved by twisting when the valve stent is stressed, so that the radial rigidity of the transition section 30 is reduced, and the radial force transmission from the support section 10 to the valve leaflet section 20 is blocked.

In other embodiments of the present application, the transition section 30 is of a split-type design with the leaflet section 20 and/or the support section 10, i.e., the transition section 30 is removably connected to the leaflet section 20 and/or the support section 10. As shown in fig. 16 and 17, the one end of the leaflet section 20, the two ends of the third link 33, and the one end of the support section 10 of this embodiment are all provided with a mounting hole, the one end of the third link 33 passes through the mounting hole through the retaining ring 60 to be connected with the one end of the leaflet section 20, and the other end of the third link 33 passes through the mounting hole through the retaining ring 60 to be connected with the one end of the support section 10, so that the two ends of the third link 33 are respectively independent from the first end point a and the support section connection point B, thereby avoiding the transmission of the torque generated by the support section 10 at the support section connection point B, and further reducing the deformation influence on the leaflet section 20.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A valve stent, characterized in that the valve stent is a tubular structure, the valve stent comprises a support section, a transition section and a valve leaflet section, the transition section is used for connecting the support section and the valve leaflet section, the valve leaflet section is used for arranging valve leaflets, the support section is used for supporting the valve stent, the maximum diameter size of the valve leaflet section is smaller than the maximum diameter size of the transition section, the maximum diameter of the transition section is smaller than or equal to the maximum diameter size of the support section, wherein, the transition section comprises a plurality of connecting rods, and the connecting rods form at least one open structural unit on the transition section.

2. The valve stent of claim 1, wherein the radial stiffness of the transition section is less than the smallest of the radial stiffness of the support section and the radial stiffness of the leaflet section.

3. The valve stent of claim 1, wherein the open structural unit comprises a first link and a second link, one end of the first link being connected to one end of the second link forming a transition section connection node, the other end of the first link being connected to the leaflet section, the other end of the second link being connected to the support section.

4. The valve stent of claim 3, wherein the support section comprises a plurality of support struts connected to one another to form support section connection points, and wherein the number of transition section connection nodes is less than the number of support section connection points.

5. The valve stent of claim 1, wherein the open structural unit comprises a plurality of third links spaced apart in a circumferential direction of the transition section, one end of the third links being connected to the leaflet segment and the other end of the third links being connected to the support segment.

6. The valve stent of claim 5, wherein a projection of the third link on a plane through a central axis of the valve stent intersects and forms an angle with the central axis of the valve stent.

7. The valve stent of claim 5, wherein a projection of the third link on a plane through a central axis of the valve stent is parallel to or coincides with the central axis of the valve stent.

8. The valve stent of claim 5, wherein a projection of the third link onto a plane tangential to the transition segment surface is any one of linear, arcuate, or dog-leg, or a combination of at least two of linear, arcuate, or dog-leg.

9. The valve stent of claim 1, wherein the transition section is removably coupled to the support section and/or the transition section is removably coupled to the leaflet section.

10. A prosthetic heart valve having the valve holder of any one of claims 1-9, further comprising: