Self-expanding heart valve stent

Abstract

The application discloses a self-expanding heart valve stent, a proximal end of the self-expanding heart valve stent comprising a fastener for fixing artificial heart valve leaflets, and a reinforcing net being arranged between the proximal end and a distal end. The reinforcing net can comprise a first self-expanding arc, a second self-expanding arc and a third self-expanding arc arranged in sequence along a direction from the distal end to the proximal end of the self-expanding heart valve stent, the first self-expanding arc being fixedly connected with the fastener and protruding towards the distal end of the heart valve stent, two ends of the second self-expanding arc being fixedly connected to the first self-expanding arc respectively and protruding towards the proximal end of the heart valve stent, the third self-expanding arc being fixedly connected with the fastener and protruding towards the distal end of the heart valve stent, and a gap being present between the second self-expanding arc and the third self-expanding arc. The self-expanding heart valve stent described herein can enable the self-expanding heart valve stent to be inflated in place.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, and in particular to a self-expanding heart valve stent. BACKGROUND

[0002] Due to the advantages of less trauma, faster recovery and the like, more and more surgeries are performed by catheterization. Aortic valve replacement surgery has also changed from the early surgical incision to the replacement of the aortic valve by catheterization. Heart valve stents are important devices for aortic valve replacement by catheterization, and are often made of nickel-titanium tubes. During surgery, the heart valve stent with sutured artificial heart valve leaflets is usually first compressed, then delivered to the site by a delivery device, and then the heart valve stent is released to expand into a cylindrical shape, driving the artificial heart valve leaflets to open. However, the heart valve stents of the prior art often cannot expand to the right position.

[0003] Chinese patent CN102413793B entitled "Stent for positioning and anchoring of implant site of valve prosthesis in heart of patient" discloses an expandable stent comprising a plurality of positioning arcs and a plurality of retaining arcs, the positioning arcs being configured to be located within a plurality of pockets on a native heart valve and on a first side of a plurality of native heart valve leaflets, and the retaining arcs being configured to be located on a second side of the plurality of native heart valve leaflets opposite the first side. The retaining arcs are divided by a plurality of curved edges into a plurality of arm segments, the arm segments being interconnected to form retaining arc arms that are linear when the stent is unexpanded. Each arm of the retaining arcs has a shape that matches a leaflet of a valve prosthesis attached to the stent. However, in the heart valve stent disclosed in the prior art, the native heart valve leaflets are directly clamped between the positioning members and the retaining arcs, which has the risk of the native heart valve leaflets interfering with the artificial heart valve leaflets.

[0004] Therefore, there is a continuing need in the art to develop a heart valve stent that can expand to the right position and avoid the native heart valve leaflets interfering with the artificial heart valve leaflets. SUMMARY

[0005] The purpose of the present application is to provide a self-expanding heart valve stent that can expand to the right position. Specifically, in the self-expanding heart valve stent described herein, a reinforcing net is provided between the fastener of the self-expanding heart valve stent and the distal end of the self-expanding heart valve stent, which can include three self-expanding arcs arranged from top to bottom, and the lowermost self-expanding arc has the largest width and the largest span. This structure solves the problem of weak radial support between adjacent retaining arcs and the self-expanding not being in the right position.

[0006] To achieve the above-mentioned purpose, the present application provides the technical solutions as follows.

[0007] In a first aspect, the present application provides a self-expanding heart valve stent, comprising a self-expanding heart valve stent distal end close to the apex of the heart when the self-expanding heart valve stent is in an expanded state and a self-expanding heart valve stent proximal end away from the apex of the heart when the self-expanding heart valve stent is in the expanded state, characterized in that the self-expanding heart valve stent proximal end comprises a connecting piece and fasteners arranged between adjacent connecting pieces, and the fasteners are used to fix artificial heart valve leaflets.

[0008] Wherein the fastener comprises a first fastening arc, a second fastening arc, and a fastener distal end connecting the first fastening arc and the second fastening arc, the first fastening arc is fixedly connected to the first connecting piece, the second fastening arc is fixedly connected to the second connecting piece, and the first connecting piece is adjacent to the second connecting piece.

[0009] Wherein the self-expanding heart valve stent distal end comprises a detent end, a reinforcing mesh is arranged between the detent end and the fastener, the distal end of the reinforcing mesh is fixed to the detent end, and the proximal end of the reinforcing mesh is fixedly connected between different fastening arcs of adjacent fasteners.

[0010] Wherein the reinforcing mesh comprises a first self-expanding arc, a second self-expanding arc, and a third self-expanding arc arranged in sequence along the direction from the self-expanding heart valve stent distal end to the self-expanding heart valve stent proximal end, one end of the first self-expanding arc is fixedly connected to the first fastening arc of the fastener, the other end is fixedly connected to the second fastening arc of the adjacent fastener, and protrudes towards the heart valve stent distal end; both ends of the second self-expanding arc are fixedly connected to the first self-expanding arc, and protrude towards the heart valve stent proximal end; one end of the third self-expanding arc is fixedly connected to the first fastening arc of the fastener, the other end is fixedly connected to the second fastening arc of the adjacent fastener, and protrudes towards the heart valve stent distal end, and there is a gap between the second self-expanding arc and the third self-expanding arc.

[0011] In an embodiment of the first aspect, the width of the first self-expanding arc is greater than the width of the second self-expanding arc and the width of the third self-expanding arc.

[0012] In an embodiment of the first aspect, the span of the first self-expanding arc is greater than the span of the second self-expanding arc and the span of the third self-expanding arc.

[0013] In an embodiment of the first aspect, the first self-expanding arc is composed of two first self-expanding arms, the proximal ends of the two first self-expanding arms are fixedly connected to the middle positions of the two fastening arcs, the distal ends of the two first self-expanding arms are connected to each other, and the distal ends of the two first self-expanding arms are also fixedly connected to the detent end.

[0014] The second self-expanding arc is composed of two second self-expanding arms, the distal ends of which are fixedly connected to the middle positions of the two first self-expanding arms, and the proximal ends of the two second self-expanding arms are connected.

[0015] The third self-expanding arc is composed of two third self-expanding arms, the proximal ends of which are fixedly connected to the positions close to the proximal ends of the two fastening arcs, and the distal ends of the two third self-expanding arms are connected.

[0016] In an embodiment of the first aspect, the proximal ends of the two third self-expanding arms are fixedly connected to the positions close to 1 / 4 of the proximal ends of the two fastening arcs.

[0017] In an embodiment of the first aspect, the length of the second self-expanding arm is not greater than half of the length of the first self-expanding arm.

[0018] In an embodiment of the first aspect, the length of the third self-expanding arm is not greater than half of the length of the second self-expanding arm.

[0019] In an embodiment of the first aspect, the length of the second self-expanding arm is half of the length of the first self-expanding arm, and the length of the third self-expanding arm is half of the length of the second self-expanding arm.

[0020] In an embodiment of the first aspect, when the self-expanding heart valve stent is in the expanded state, the first fastening arc of the fastener and the second fastening arc of the adjacent fastener form a first fillet, the first self-expanding arc has a second fillet, and the third self-expanding arc has a third fillet. In this embodiment, the third fillet is not greater than the first fillet formed by the adjacent fastening arc, and the second fillet is greater than the first fillet and the third fillet.

[0021] In an embodiment of the first aspect, the reinforcing net further comprises other self-expanding arcs, which are arranged inside the second self-expanding arc or inside the third self-expanding arc, and the sum of the number of self-expanding arcs of the reinforcing net is less than or equal to 5.

[0022] In an embodiment of the first aspect, the reinforcing net further comprises a fourth self-expanding arc arranged inside the second self-expanding arc, the fourth self-expanding arc is composed of two fourth self-expanding arms, the distal ends of which are fixedly connected to the two first self-expanding arms, and the proximal ends of the two fourth self-expanding arms are connected. The width of the fourth self-expanding arm is less than the width of the self-expanding arm of the first self-expanding arc, and not greater than the width of the self-expanding arm of the second self-expanding arc.

[0023] In an implementation form of the first aspect, the reinforcing net further comprises a fourth self-expanding arc arranged inside the second self-expanding arc, the fourth self-expanding arc being composed of two fourth self-expanding arms, proximal ends of the two fourth self-expanding arms being fixedly connected with the two second self-expanding arms respectively, and distal ends of the two fourth self-expanding arms being connected. The fourth self-expanding arms have a width smaller than the width of the self-expanding arms of the first self-expanding arc and not greater than the width of the self-expanding arms of the second self-expanding arc.

[0024] In an implementation form of the first aspect, when the self-expanding heart valve stent is in the expanded state, the fourth self-expanding arc has a fourth rounded corner, the fourth rounded corner being not greater than the proximal rounded corner formed by the second self-expanding arc.

[0025] In an implementation form of the first aspect, the reinforcing net further comprises a fifth self-expanding arc arranged inside the third self-expanding arc, the fifth self-expanding arc being composed of two fifth self-expanding arms, proximal ends of the two fifth self-expanding arms being fixedly connected with the two second self-expanding arms at positions close to the proximal ends respectively, and distal ends of the two fifth self-expanding arms being connected. The fifth self-expanding arms have a width not greater than the width of the self-expanding arms of the third self-expanding arc.

[0026] In an implementation form of the first aspect, the reinforcing net further comprises a fifth self-expanding arc arranged inside the third self-expanding arc, the fifth self-expanding arc being composed of two fifth self-expanding arms, distal ends of the two fifth self-expanding arms being fixedly connected with the two third self-expanding arms respectively, and proximal ends of the two fifth self-expanding arms being connected. The fifth self-expanding arms have a width not greater than the width of the self-expanding arms of the third self-expanding arc.

[0027] In an implementation form of the first aspect, when the self-expanding heart valve stent is in the expanded state, the third self-expanding arc has a third rounded corner, and the fifth self-expanding arc has a fifth rounded corner, the fifth rounded corner being not greater than the third rounded corner.

[0028] In one embodiment of the first aspect, the self-expandable heart valve stent further comprises a support member and a positioning member disposed between adjacent connectors, the support member comprising a first support arm, a second support arm, and a support member distal end connecting the first support arm and the second support arm, the first support arm being fixedly connected to a first connector, the second support arm being fixedly connected to a second connector, the first connector being adjacent to the second connector. In this embodiment, the positioning member comprises a first positioning arm, a second positioning arm, and a positioning member distal end connecting the first positioning arm and the second positioning arm, the first positioning arm being fixedly connected to a first connector, the second positioning arm being fixedly connected to a second connector, the first connector being adjacent to the second connector. In this embodiment, the positioning member is closer to the anti-regurgitation heart valve stent distal end than the support member, the fastener is closer to the anti-regurgitation heart valve stent distal end than the positioning member, the support member distal end and the positioning member distal end are rods protruding towards the anti-regurgitation heart valve stent distal end, the support member is disposed on one side of the native heart valve leaflet, and the positioning member is disposed on the other side of the native heart valve leaflet.

[0029] Compared with the prior art, the application has the following beneficial effects:

[0030] (1) A reinforcing net is disposed between the fastener at the proximal end of the self-expandable heart valve stent and the clamping end at the distal end of the self-expandable heart valve stent, the reinforcing net comprises three self-expanding arcs disposed in sequence from the proximal end to the distal end, and the lowermost self-expanding arc has the largest width and the largest span, thereby providing the required radial expansion force, so that the self-expandable heart valve stent is expanded into place;

[0031] (2) A support member is disposed at the proximal end of the self-expandable heart valve stent, so that the native heart valve leaflet is clamped between the support member and the positioning member, and the artificial heart valve leaflet is clamped between the positioning member and the fastener, thereby avoiding the native heart valve leaflet from interfering with the artificial heart valve leaflet. In this embodiment, the upper part of the native valve leaflet is combined by the support member and the positioning member, and the lower part of the native valve leaflet is clamped by the positioning member and the fastener. The artificial valve leaflet is connected to the heart valve stent along the fastener, the native valve leaflet is outside the fastener, and the artificial valve leaflet is inside the fastener. BRIEF DESCRIPTION OF DRAWINGS

[0032] The technical features and advantages of the application can be more fully understood by referring to the following detailed description in conjunction with the accompanying drawings.

[0033] Figure 1 A perspective view showing a self-expandable heart valve stent according to one embodiment of the application in an expanded state.

[0034] Figure 2 A perspective view showing a self-expandable heart valve stent according to one embodiment of the application in an expanded state. Figure 1 A perspective view showing a self-expandable heart valve stent according to one embodiment of the application in an expanded state.

[0035] Figure 3 shows Figure 2 a partial enlarged view of region A.

[0036] Figure 4 shows Figure 2 a partial enlarged view of region B.

[0037] Figure 5 shows a perspective view of an anti-reflux heart valve stent according to another embodiment in an expanded state.

[0038] Figure 6 shows a deployment view of an anti-reflux heart stent as Figure 5

[0039] Figure 7 shows Figure 6 a partial enlarged view of region B. DETAILED DESCRIPTION

[0040] Unless otherwise defined, technical or scientific terms used in the present specification and claims should have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains.

[0041] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplification of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0042] In addition, the terms "first", "second", and the like are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second", and the like can include one or more of the features explicitly or implicitly. In the description of the present application, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0043] ​In the description of the application, it is necessary to point out that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, it can be connected, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0044] As described herein, when describing the heart valve stent, "proximal" refers to the side of the heart valve stent that is located on the side of the delivery device or on the side of the end manipulated by the user when the heart valve stent assumes an expanded state. Correspondingly, "distal" refers to the side of the heart valve stent that is away from the side of the delivery device or away from the end manipulated by the user when the heart valve stent assumes an expanded state. In this application, when describing the heart valve stent, "proximal cardiac end" refers to the side of the heart valve stent that is close to the apex of the heart when the heart valve stent assumes an expanded state. Correspondingly, "distal cardiac end" refers to the side of the heart valve stent that is away from the apex of the heart when the heart valve stent assumes an expanded state. Because the heart valve stent described herein is delivered through the aorta by catheter, the distal end and the proximal cardiac end refer to the same position, and the proximal end and the distal cardiac end refer to the same position, but this does not exclude the use of a transapical method for implantation, only the heart valve stent described herein is delivered through the aorta by catheter as an example for description.

[0045] Embodiment 1

[0046] The embodiment relates to a self-expanding heart valve stent, the proximal end of the self-expanding heart valve stent comprises a support, a positioning member and a fastener arranged between the connectors, the distal end of the self-expanding heart valve stent comprises a clamping end, and a reinforcing net is arranged between the fastener and the clamping end. The reinforcing net comprises three self-expanding arcs arranged in sequence from the proximal end to the distal end, and the self-expanding arc closest to the distal end has the longest width and span, and can provide sufficient radial expansion force, so that the self-expanding heart valve stent can be expanded in place. In addition, the self-expanding heart valve stent of the embodiment can clamp the distal cardiac end of the native heart valve leaflet between the support and the positioning member, and clamp the proximal cardiac end of the native heart valve leaflet between the positioning member and the fastener, thereby avoiding the interference of the native heart valve leaflet with the artificial heart valve leaflet.

[0047] Firstly referring to Figures 1-4The heart valve stent described in the present embodiment can include a distal end of the heart valve stent close to the apex when the heart valve stent is in the expanded state and a proximal end of the heart valve stent away from the apex when the heart valve stent is in the expanded state. The proximal end of the heart valve stent can include the connectors 14 and the supports 11, the positioners 12 and the fasteners 13 arranged between adjacent connectors. The supports 11 and the positioners 12 can be used to fix the native leaflets, while the fasteners 13 can be used to fix the artificial leaflets, which can be directly fixed or indirectly fixed through other media, such as fixing a covering film with the fasteners and then fixing the artificial leaflets with the covering film.

[0048] In the present embodiment, the supports can include a first support arm 111, a second support arm 112 and a distal end 113 of the supports connecting the first support arm 111 and the second support arm 112. The first support arm 111 is fixedly connected to a first connector, the second support arm 112 is fixedly connected to a second connector, and the first connector is adjacent to the second connector. Similarly, the positioners 12 can include a first positioning arm 121, a second positioning arm 122 and a distal end 123 of the positioners connecting the first positioning arm and the second positioning arm. The first positioning arm 121 is fixedly connected to a first connector, and the second positioning arm 122 is fixedly connected to a second connector, and the first connector is adjacent to the second connector. In addition, the fasteners 13 include a first fastening arc 131, a second fastening arc 132 and a distal end 133 of the fasteners connecting the first fastening arc and the second fastening arc. The first fastening arc is fixedly connected to a first connector, the second fastening arc is fixedly connected to a second connector, and the first connector is adjacent to the second connector.

[0049] In the present embodiment, the positioners 12 are closer to the distal end of the heart valve stent than the supports 11, and the fasteners 13 are closer to the distal end of the heart valve stent than the positioners 12. The distal end 113 of the supports and the distal end 123 of the positioners are rods protruding towards the distal end of the heart valve stent. The supports 11 are arranged on one side of the native leaflets, and the positioners 12 are arranged on the other side of the native leaflets.

[0050] Compared with conventional heart valve stents, the heart valve stent described herein further includes supports 11, so that the native leaflets can be clamped between the supports 11 and the positioners 12. The supports 11 prevent the native leaflets from interfering with the artificial leaflets, and since the native leaflets are clamped by the supports and the positioners, the clamping is relatively more secure. In addition, the supports facilitate the heart valve stent to expand more smoothly, increasing the radial force during expansion.

[0051] In one specific embodiment, reference is made to Figure 2When the heart valve stent is in the compressed state, the first support arm and the second support arm are linear. When the heart valve stent is in the compressed state, the first positioning arm and the second positioning arm are linear. The first positioning arm and the second positioning arm are designed to be linear to facilitate compression, and when fully compressed, they occupy the smallest space, i.e. the adjacent first support arm and second support arm are fully close when compressed. Moreover, the linear structure can ensure that the two do not interfere when compressed, so the purpose of the first positioning arm and the second positioning arm being linear is also to fully close when compressed without interference. In addition, the stent is cut from a nickel-titanium tube, but it should be noted that the material used can be any material that can be implanted in the human body, and the linear design is also beneficial for processing, shortening the processing path and reducing processing costs.

[0052] In one embodiment, the distal end of the positioning member is a parabolic structure, which reduces the contact stress between the positioning member and the sinus floor and prevents the annulus from rupturing.

[0053] In one embodiment, the width of the fastener 13 is wider than the width of the support member 11 and the positioning member 12 to provide strong support, and the width mainly refers to the width of the rod.

[0054] In one embodiment, when the heart valve stent is in the expanded state, the support member has a first opening angle, which facilitates clamping the native leaflet between the support member and the positioning member, and the positioning member has a second opening angle, which is 4°-14°, and the first opening angle is smaller than the second opening angle. The positioning member 12 and the fastener 13 have a certain opening angle, which facilitates the positioning member 12 to capture the leaflet and reduces the difficulty of the operation. The positioning member 12 can be used to prevent the annulus from moving in the ventricular direction, promote the distal end of the artificial heart valve to align with the native heart valve, maximize the restoration of the function of the native heart valve, and at the same time keep the artificial heart valve in the original position of the native heart valve, so the artificial heart valve well replaces the native heart valve, reduces the impact on blood flow, and reduces the occurrence of thrombosis. The second opening angle of 4°-14° can make the positioning member 12 and the fastener 13 clamp the native heart valve, prevent the native heart valve from moving freely, and at the same time, the native heart valve is closely attached to the stent, reducing paravalvular leakage.

[0055] In one embodiment, the vertical distance between the distal end of the positioning member closest to the distal end of the heart valve stent and the distal end of the heart valve stent farthest away (i.e. the detent end 16 described below) is 4mm-8mm, preferably 6mm.

[0056] In one embodiment, the distal end of the locking end is outwardly flared relative to the proximal end of the locking end, and the angle of the distal end of the locking end outwardly flared relative to the proximal end of the locking end is 6°-14°. The reason for creating the outward flaring is to prevent the self-expandable heart valve stent from moving in the direction of the aorta, thereby anchoring the stent. At the same time, the reason for not creating too large an angle is to prevent touching the His bundle, thereby affecting the normal beating of the heart and endangering life.

[0057] In one embodiment, referring to Figure 1 and Figure 2 , the distal end of the self-expandable heart valve stent further comprises a locking end 16 and a reinforcing net 15, and there is a hollow structure 17 between the locking end 16 and the reinforcing net 15. In this embodiment, the number of rhombic squares of the locking end 16 is 18, which effectively increases the compressibility of the heart valve stent, and the width of the bars constituting the rhombic squares is gradually changed (narrow in the middle and wide at both ends) to optimize the fatigue resistance of the stent. In addition, because the heart valve stent described herein only includes 18 rhombic squares, only one reinforcing net 15 is needed to connect the locking end between adjacent fastening arcs of the heart valve stent, which can form a large number of hollow parts, effectively reducing the weight of the heart valve stent, and facilitating compression, and the width of the bars constituting the rhombic squares is gradually changed (narrow in the middle and wide at both ends) to optimize the fatigue resistance of the stent. In addition, the presence of the reinforcing net 15 can increase the structural strength of the middle of the stent and isolate the native valve leaflets to prevent invasion of the artificial heart valve leaflets.

[0058] Next, more technical features of the locking end 16 and the reinforcing net 15 will be described in more detail with reference to Figure 3 and Figure 4 .

[0059] In one embodiment, referring to Figure 3 , the reinforcing net 15 is provided between the locking end 16 and the fastener 13, the distal end of the reinforcing net 15 is fixed to the locking end 16, and the proximal end of the reinforcing net 15 is fixedly connected between different fastening arcs of adjacent fasteners 13.

[0060] The reinforcing net can include a first self-expanding arc 151, a second self-expanding arc 152 and a third self-expanding arc 153 arranged in sequence along a direction from the distal end of the self-expanding heart valve stent to the proximal end of the self-expanding heart valve stent. One end of the first self-expanding arc is fixedly connected to the first fastening arc of the fastener, the other end is fixedly connected to the second fastening arc of the adjacent fastener, and protrudes towards the distal end of the heart valve stent. The two ends of the second self-expanding arc are fixedly connected to the first self-expanding arc respectively, and protrude towards the proximal end of the heart valve stent. One end of the third self-expanding arc is fixedly connected to the first fastening arc of the fastener, the other end is fixedly connected to the second fastening arc of the adjacent fastener, and protrudes towards the distal end of the heart valve stent. There is a gap between the second self-expanding arc and the third self-expanding arc.

[0061] In a specific embodiment, the width of the first self-expanding arc 151 is greater than the width of the second self-expanding arc 152 and the third self-expanding arc 153. The size of the first self-expanding arc 151 is the largest among the sizes of the second self-expanding arc 152 and the third self-expanding arc 153, and the span is also the largest, so the first self-expanding arc 151 needs to provide greater radial support force, thereby ensuring its stable support performance. Therefore, the width of the first self-expanding arc 151 is wider, and the reinforcing net formed by the first self-expanding arc 151, the second self-expanding arc 152 and the third self-expanding arc 153 is arranged, which not only can still prevent the native heart valve leaflets from interfering with the artificial heart valve leaflets, but also solves the problem of weak radial support force between adjacent fastening arcs and incomplete self-expansion.

[0062] In a specific embodiment, the first self-expanding arc 151 is composed of two first self-expanding arms 1511, the proximal ends of the two first self-expanding arms 1511 are fixedly connected to the middle positions of the two fastening arcs respectively, and the distal ends of the two first self-expanding arms 1511 are connected to each other, and the connection position is also fixedly connected to the clamping end 16.

[0063] In a specific embodiment, the second self-expanding arc 152 is composed of two second self-expanding arms 1521, the distal ends of the two second self-expanding arms 1521 are fixedly connected to the middle positions of the two first self-expanding arms 1511 respectively, and the proximal ends of the two second self-expanding arms 1521 are connected. The length of the second self-expanding arm 1521 is not greater than half the length of the first self-expanding arm 1511. Preferably, the length of the second self-expanding arm 1521 is half the length of the first self-expanding arm 1511.

[0064] In a specific embodiment, the third self-expanding arc 153 is composed of two third self-expanding arms 1531, the proximal ends of the two third self-expanding arms 1531 are fixedly connected to the positions close to the proximal end of the two fastening arcs, and the distal ends of the two third self-expanding arms 1531 are connected. The length of the third self-expanding arm 1531 is not greater than half the length of the second self-expanding arm 1521. Preferably, the length of the third self-expanding arm 1531 is half the length of the second self-expanding arm 1521.

[0065] The above design can realize reasonable use of space and realize the structure by using one pipe.

[0066] In the embodiment, when the heart valve stent is in the expanded state, the first fastening arc 131 of the fastener 13 and the second fastening arc 132 of the adjacent fastener form a first fillet 154, the second self-expanding arc 151 has a second fillet 155, and the third self-expanding arc 153 has a third fillet 156. The third fillet 156 is not greater than the first fillet 154 formed by the adjacent fastening arcs. Because the space is smaller, that is, the amount of material is more, and the material space is less, the closer to the connection of the proximal end of the fastener. Assuming that the third fillet 156 is greater than the first fillet 154, when the self-expanding heart valve stent is compressed, the two third self-expanding arms are closer to each other relative to the two fastening arcs, so the two third self-expanding arms are very close to each other. Therefore, the excessive third fillet 156 prevents the two third self-expanding arms from approaching each other, and even blocks the adjacent fastening arcs from approaching each other, so that the reflux stent is difficult to compress, and even the excessive third fillet 156 is broken due to excessive extrusion during compression. The first self-expanding arc 151 corresponding to the second fillet 155 has a large span, so a sufficient support force needs to be provided to satisfy the large span, so the second fillet 155 is greater than the first fillet 154 and the third fillet 156. For the same reason as the size relationship between the third fillet 156 and the first fillet 154, the second fillet 155 is greater than the fillet formed by the connection of the two second self-expanding arms 1521 of the second self-expanding arc 152.

[0067] In the embodiment, the first self-expanding arc 151, the second self-expanding arc 152, and the third self-expanding arc 153 are provided, but this does not mean that the reinforcing net only has three self-expanding arcs.

[0068] In a specific embodiment, a fourth self-expanding arc (not shown in the figure) can be provided on the inner side of the second self-expanding arc 152, and when the self-expanding heart valve stent is in the expanded state, the fillet formed by the connection of the two self-expanding arms of the fourth self-expanding arc is not greater than the fillet formed by the connection of the two second self-expanding arms 1521 of the corresponding second self-expanding arc 152, and the width of the self-expanding arm of the fourth self-expanding arc is not greater than the width of the self-expanding arm of the first self-expanding arc connected thereto, thereby reducing the space occupancy.

[0069] In another embodiment, the reinforcing net 15 further comprises a fourth self-expanding arc (not shown in the figure) arranged inside the second self-expanding arc 152, the fourth self-expanding arc is composed of two fourth self-expanding arms, the distal ends of the two fourth self-expanding arms are respectively fixedly connected with the two first self-expanding arms, and the proximal ends of the two fourth self-expanding arms are connected. The width of the fourth self-expanding arm is less than the width of the self-expanding arm of the first self-expanding arc 151, and is not greater than the width of the self-expanding arm of the second self-expanding arc 152.

[0070] In another embodiment, a fourth self-expanding arc (not shown in the figure) can be arranged inside the second self-expanding arc, the fourth self-expanding arc is composed of two fourth self-expanding arms, the proximal ends of the two fourth self-expanding arms are respectively fixedly connected with the two second self-expanding arms, and the distal ends of the two fourth self-expanding arms are connected. The width of the fourth self-expanding arm is less than the width of the self-expanding arm of the first self-expanding arc, and is not greater than the width of the self-expanding arm of the second self-expanding arc. In another embodiment, a new self-expanding arc can also be arranged inside the fourth self-expanding arc, and the total number of self-expanding arcs of the self-expanding heart valve stent is not more than five.

[0071] In a specific embodiment, a fifth self-expanding arc (not shown in the figure) can be arranged inside the third self-expanding arc 153, when the self-expanding heart valve stent is in an expanded state, the third self-expanding arc has a third circular corner, the fifth self-expanding arc has a fifth circular corner, the fifth circular corner is not greater than the third circular corner, and the width of the self-expanding arm of the fifth self-expanding arc is not greater than the width of the self-expanding arm of the first self-expanding arc and / or the fastening arc of the fastener connected therewith, so as to reduce the space occupancy.

[0072] In another embodiment, a fifth self-expanding arc (not shown in the figure) can also be arranged inside the third self-expanding arc 153, but the total number of self-expanding arcs of the reinforcing net is not more than five, so as not to affect the compression performance of the self-expanding heart valve stent. When the self-expanding heart valve stent is in an expanded state, the fifth self-expanding arc can have a fifth circular corner, which is not greater than the first circular corner for the same reason as the third self-expanding arc. The width of the fifth self-expanding arc is not greater than the width of the fastening arc of the fastener connected with the fifth self-expanding arc.

[0073] In another embodiment, a fifth self-expanding arc (not shown in the figure) can be arranged inside the third self-expanding arc, the fifth self-expanding arc is composed of two fifth self-expanding arms, the proximal ends of the two fifth self-expanding arms are respectively fixedly connected with the two fastening arcs near the proximal ends, and the distal ends of the two fifth self-expanding arms are connected. The width of the fifth self-expanding arm is not greater than the width of the self-expanding arm of the third self-expanding arc.

[0074] In another embodiment, the reinforcing net 15 further comprises a fifth self-expanding arc (not shown in the figure) arranged inside the third self-expanding arc 153, the fifth self-expanding arc is composed of two fifth self-expanding arms, the distal ends of the two fifth self-expanding arms are fixedly connected with the two third self-expanding arms 153 respectively, and the proximal ends of the two fifth self-expanding arms are connected, the width of the fifth self-expanding arm is not greater than the width of the self-expanding arm of the third self-expanding arc.

[0075] In a specific embodiment, referring to Figure 4 , the distal end of the self-expanding heart valve stent can comprise a locking end 16, the locking end 16 comprises a plurality of locking end structural units 161 connected with each other, and the width of the rod 162 constituting the locking end structural unit 161 is small in the middle and large at both ends. Figure 4 In the embodiment shown in the figure, the rod 162 of the locking end structural unit 161 can be symmetrical, wherein the width in the middle is the smallest, and then smoothly increases towards both ends without stepwise mutation. Therefore, the edges of the rod 162 are smooth.

[0076] In a specific embodiment, the locking end structural unit 161 is a rhombic lattice, and the locking end 16 can comprise 15 or 18 locking end structural units 161 arranged in one layer and connected with each other. Adjacent locking end structural units 161 can be connected with each other by sharing a vertex. The connection areas of adjacent locking end structural units 161 respectively extend along the circumferential direction and the longitudinal direction of the self-expanding heart valve stent by a predetermined length, and the connection area of the adjacent locking end structural units along the circumferential direction of the self-expanding heart valve stent comprises a curved structure 163 recessed towards it. Because the width of both ends of the rod 162 is the widest, the deformation is the most difficult at the position of the rod 162 closest to the connection area of the locking end structural unit 161, so a larger stress is generated in the process of compression and expansion, which is easy to cause the rod 162 to break at the position closest to the connection area of the locking end structural unit 161. By increasing the curved structure 163, the bending stress of the rod 62 at the position closest to the connection area of the locking end structural unit 161 is reduced, which can prevent the rod 162 from breaking in the compression and self-expanding process of the locking end of the stent.

[0077] Next, the structure of the connector 14 of the present embodiment will be described in more detail. Referring back to Figures 1-2 , the connector 14 can comprise a connecting block 141, a connecting web 142 and a connecting frame 143. One end of the connecting block 141 forms the proximal end of the heart valve stent, and the other end is connected with the connecting frame 143 through the connecting web 142, and the connecting block 141 is used to connect with a delivery device for delivering the heart valve stent.

[0078] Referring back to Figure 2In one embodiment, the connecting frame 143 can include a support connecting portion, a positioning connecting portion and a fastener connecting portion in sequence along the direction from the proximal end of the heart valve stent to the distal end of the heart valve stent. In one embodiment, the support connecting portion can be symmetrical, one side connected with the first support arm of the first support member and the other side connected with the second support arm of the adjacent second support member. In one preferred embodiment, the upper edge of the support arm connecting portion of the connecting frame is a smooth arc, and the angle of the arc is 100°-160°. Meanwhile, the lower edge of the support arm connecting portion of the connecting frame is also a smooth arc, and the angle of the arc is an acute angle.

[0079] In one embodiment, the width of the connecting web is less than the width of the connecting block and the width of the support connecting portion. In another embodiment, the connecting frame includes a hollow long strip-shaped suture hole 144. One end of the long strip-shaped suture hole 144 can be arranged at the support connecting portion, and the other end can be arranged at the positioning connecting portion or the fastener connecting portion. The long strip-shaped suture hole 144 can enable the proximal edge of the artificial heart valve leaflet to be directly sutured through the suture hole without the need to add a suture gasket, and the edge of the artificial heart valve leaflet is sutured with the fastener arc. Such a suture method, compared with the traditional method of using a gasket and stent to press and fix the valve leaflet, first reduces the additional parts of the stent, and without the gasket, it is also beneficial for further compression of the stent. If there is a gasket, not only does it affect the compression of the stent, but it can also damage the artificial heart valve leaflet in some cases when the stent is compressed and the stent is small.

[0080] In another embodiment, the positioning member can comprise a pull wire composite ring 124 fixedly connected to the positioning member and located on the side of the positioning member facing the proximal end of the heart valve stent, the pull wire composite ring comprising a first through hole 1241 for mounting a marker and a second through hole 1242 adapted to pass through a pull wire, and the second through hole is closer to the proximal end of the heart valve stent than the first through hole. In a specific embodiment, the diameter of the first through hole is larger than the diameter of the second through hole. The pull wire composite ring structure provided at the distal end of the positioning member combines the installation of the pull wire and the marker (the marker is radiopaque) into one position, effectively reducing the space occupation of the product. With one position, the opening and closing control and positioning of the positioning member can be achieved, not only improving the compression performance of the product, which is beneficial for the product to be transported by a catheter, but also the opening of the positioning member can also reduce the difficulty of surgical operation. The pull wire composite ring structure has two through holes, the large hole is for placing the marker point to facilitate accurate positioning and ensure that the positioning member touches the sinus floor, and the small hole is convenient for passing through the pull wire. During implantation, the pull wire is used to control the opening angle of the positioning member, which is convenient for capturing the leaflets and reduces the operation difficulty. In a preferred embodiment, the pull wire composite ring is provided at the distal end of the positioning member and is inclined inward relative to the stent axis, preventing the proximal end of the pull wire composite ring from colliding with the aortic wall during stent shaking, thereby damaging the aorta and even causing aortic dissection and threatening the life of the user. Therefore, the positioning member can be pulled outward of the heart valve stent by the pull wire.

[0081] In the embodiment shown in the drawings, the heart valve stent can comprise three structurally identical support members, positioning members, fastening members and connecting members. Adjacent connecting members are connected by support members, positioning members and fastening members. At the same time, adjacent support members, positioning members and fastening members are connected by connecting members. When the heart valve stent is in an extended state, it is basically cylindrical. Artificial heart valve leaflets can be clamped between the support members and the positioning members.

[0082] Example 2

[0083] The difference between this embodiment 2 and embodiment 1 is that the self-expanding heart valve stent of this embodiment does not comprise a support member. This embodiment relates to a self-expanding heart valve stent, the proximal end of which comprises positioning members and fastening members arranged between connecting members, the distal end of which comprises a clamping end, and a reinforcing net is arranged between the fastening members and the clamping end. The reinforcing net comprises three self-expanding arcs arranged in sequence from the proximal end to the distal end, and the self-expanding arc closest to the distal end has the longest width and span, which can provide sufficient radial expansion force to enable the self-expanding heart valve stent to expand into place.

[0084] Reference Figures 5-7The self-expanding heart valve stent of the present embodiment is different from the self-expanding heart valve stent of embodiment 1 in that it does not contain a support member, and the descriptions of the positioning member, the fastener, the connecting member, the reinforcing mesh, the clamping end, and the self-expanding arc in embodiment 1 also apply to the present embodiment, and thus will not be repeated here.

[0085] It will be apparent to those skilled in the art that the application is not limited to the details of the foregoing exemplary embodiments and that the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. No reference signs in the claims shall be construed as limiting the scope of the claims.

Claims

1. A self-expanding heart valve stent comprising a distal end of the self-expanding heart valve stent proximal to the apex of the heart when the self-expanding heart valve stent is in an expanded state and a proximal end of the self-expanding heart valve stent distal to the apex of the heart when the self-expanding heart valve stent is in an expanded state, characterized in that, The proximal end of the self-expanding heart valve stent comprises connectors and fasteners, supports and positioning members arranged between adjacent connectors, the fasteners are used to fix artificial heart valve leaflets, and the supports and positioning members are used to clamp native heart valve leaflets; The fastener comprises a first fastening arc, a second fastening arc and a fastener distal end connecting the first fastening arc and the second fastening arc, the first fastening arc is fixedly connected to the first connector, the second fastening arc is fixedly connected to the second connector, and the first connector is adjacent to the second connector; The support comprises a first support arm, a second support arm and a support distal end connecting the first support arm and the second support arm, the first support arm is fixedly connected to the first connector, and the second support arm is fixedly connected to the second connector; The positioning member comprises a first positioning arm, a second positioning arm and a positioning member distal end connecting the first positioning arm and the second positioning arm, the first positioning arm is fixedly connected to the first connector, and the second positioning arm is fixedly connected to the second connector; The positioning member is closer to the distal end of the self-expanding heart valve stent than the support, the fastener is closer to the distal end of the self-expanding heart valve stent than the positioning member, the support distal end and the positioning member distal end are rods protruding towards the distal end of the self-expanding heart valve stent, the support is arranged on one side of the native heart valve leaflet, and the positioning member is arranged on the other side of the native heart valve leaflet; The distal end of the self-expanding heart valve stent comprises a clamping end, the distal end of the clamping end is outwardly expanded relative to the proximal end of the clamping end, and the angle of the distal end of the clamping end outwardly expanded relative to the proximal end of the clamping end is 6°-14°, a reinforcing net is arranged between the clamping end and the fastener, the distal end of the reinforcing net is fixed to the clamping end, and the proximal end of the reinforcing net is fixedly connected between different fastening arcs of adjacent fasteners; The reinforcing net comprises a first self-expanding arc, a second self-expanding arc and a third self-expanding arc arranged in sequence along the direction from the distal end of the self-expanding heart valve stent to the proximal end of the self-expanding heart valve stent, one end of the first self-expanding arc is fixedly connected to the first fastening arc of the fastener, the other end is fixedly connected to the second fastening arc of the adjacent fastener, and protrudes towards the distal end of the heart valve stent; The width and span of the first self-expanding arc are greater than the width and span of the second self-expanding arc and the third self-expanding arc, respectively; The two ends of the second self-expanding arc are fixedly connected to the first self-expanding arc, respectively, and protrude towards the proximal end of the heart valve stent; one end of the third self-expanding arc is fixedly connected to the first fastening arc of the fastener, the other end is fixedly connected to the second fastening arc of the adjacent fastener, and protrudes towards the distal end of the heart valve stent, the second self-expanding arc and the third self-expanding arc are spaced apart in the axial direction and are not directly connected; the reinforcing net further comprises other self-expanding arcs, the other self-expanding arcs are arranged inside the second self-expanding arc or inside the third self-expanding arc, and the sum of the number of self-expanding arcs of the reinforcing net is less than or equal to 5.

2. The self-expanding heart valve stent of claim 1, wherein, The first self-expanding arc is composed of two first self-expanding arms, the proximal ends of the two first self-expanding arms are fixedly connected with the middle positions of the two fastening arcs respectively, the distal ends of the two first self-expanding arms are connected with each other, and the distal ends of the two first self-expanding arms are also fixedly connected with the clamping end; The second self-expanding arc is composed of two second self-expanding arms, the distal ends of the two second self-expanding arms are fixedly connected with the middle positions of the two first self-expanding arms respectively, and the proximal ends of the two second self-expanding arms are connected with each other. The third self-expanding arc is composed of two third self-expanding arms, the proximal ends of the two third self-expanding arms are fixedly connected with positions close to the proximal ends of the two fastening arcs respectively, and the distal ends of the two third self-expanding arms are connected with each other.

3. The self-expanding heart valve stent of claim 2, wherein, The proximal ends of the two third self-expanding arms are fixedly connected with positions 1 / 4 close to the proximal ends of the two fastening arcs respectively.

4. The self-expanding heart valve stent of claim 3, wherein, The length of the second self-expanding arm is half of the length of the first self-expanding arm, and the length of the third self-expanding arm is half of the length of the second self-expanding arm.

5. The self-expanding heart valve stent of claim 3, wherein, When the self-expanding heart valve stent is in the expanded state, the first fastening arc of the fastener and the second fastening arc of the adjacent fastener form a first fillet, the first self-expanding arc has a second fillet, and the third self-expanding arc has a third fillet. The third fillet is not greater than the first fillet formed by the adjacent fastening arc, and the second fillet is greater than the first fillet and the third fillet.

6. The self-expanding heart valve stent of claim 1, wherein, The reinforcing net further comprises a fourth self-expanding arc arranged inside the second self-expanding arc, the fourth self-expanding arc is composed of two fourth self-expanding arms, the distal ends of the two fourth self-expanding arms are fixedly connected with the two first self-expanding arms respectively, and the proximal ends of the two fourth self-expanding arms are connected with each other. The width of the fourth self-expanding arm is less than the width of the self-expanding arm of the first self-expanding arc, and is not greater than the width of the self-expanding arm of the second self-expanding arc.

7. The self-expanding heart valve stent of claim 1, wherein, The reinforcing net further comprises a fourth self-expanding arc arranged inside the second self-expanding arc, the fourth self-expanding arc is composed of two fourth self-expanding arms, the proximal ends of the two fourth self-expanding arms are fixedly connected with the two second self-expanding arms respectively, and the distal ends of the two fourth self-expanding arms are connected with each other. The width of the fourth self-expanding arm is less than the width of the self-expanding arm of the first self-expanding arc, and is not greater than the width of the self-expanding arm of the second self-expanding arc.

8. The self-expanding heart valve stent of claim 6 or 7, wherein, When the self-expanding heart valve stent is in the expanded state, the fourth self-expanding arc has a fourth fillet, and the fourth fillet is not greater than the proximal end fillet formed by the second self-expanding arc.

9. The self-expanding heart valve stent of claim 1, wherein, The reinforcing net further comprises a fifth self-expanding arc arranged inside the third self-expanding arc, the fifth self-expanding arc is composed of two fifth self-expanding arms, the proximal ends of the two fifth self-expanding arms are fixedly connected with positions close to the proximal ends of the two fastening arcs respectively, and the distal ends of the two fifth self-expanding arms are connected with each other. The width of the fifth self-expanding arm is not greater than the width of the self-expanding arm of the third self-expanding arc.

10. The self-expanding heart valve support of claim 1, wherein, The reinforcing net further comprises a fifth self-expanding arc arranged inside the third self-expanding arc, the fifth self-expanding arc is composed of two fifth self-expanding arms, the distal ends of the two fifth self-expanding arms are fixedly connected with the two third self-expanding arcs respectively, and the proximal ends of the two fifth self-expanding arms are connected with each other. The width of the fifth self-expanding arm is not greater than the width of the self-expanding arm of the third self-expanding arc.

11. The self-expanding heart valve stent of claim 9 or 10, wherein, When the self-expanding heart valve stent is in the expanded state, the third self-expanding arc has a third fillet, and the fifth self-expanding arc has a fifth fillet, the fifth fillet being no greater than the third fillet.

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