Valve stent and valve prosthesis system

Abstract

The application discloses a valve stent and a valve prosthesis system, and the valve stent comprises an inner stent, a plurality of first stents and a valve ring matching part; the plurality of first stents are arranged along the axial extension of the valve stent, the outflow ends of the first stents are connected to the outside of the inner stent through the valve ring matching part, and the plurality of first stents and the valve ring matching part are arranged along the circumference of the inner stent; when the first stents are in an unfolded state, the plurality of first stents form a space with a spherical shape or a spherical-like shape for supporting an atrium; and the valve ring matching part is used for matching with a valve ring. In this way, the first stents support the atrium, the valve stent can be prevented from moving in the front-back, left-right and up-down directions and from being displaced when the heart beats, and the radial supporting force of the valve ring matching part is supported at the valve ring, so that the valve prosthesis can be further prevented from being deflected and displaced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a valve stent and a valve prosthesis system. BACKGROUND

[0002] The mitral valve is a valve in the heart that separates the left atrium and left ventricle. The mitral valve acts as a one-way valve, opening and closing to ensure blood flows in one direction. Normally, the mitral valve lets blood flow from the left atrium to the left ventricle, but if the mitral valve does not close properly, some blood can flow back into the left atrium when the heart contracts. This is called mitral regurgitation. Mitral regurgitation puts extra strain on the heart, lungs and other organs. In some people, the heart has to work harder to pump blood around the body, which can cause the heart to enlarge. As the condition gets worse, other serious heart problems can develop (such as heart failure), and can lead to irregular heartbeats, brain haemorrhage, and even sudden death. In recent years, with the progress of minimally invasive interventional therapy technology, transcatheter heart valve replacement surgery has been rapidly developed and applied in clinical practice. The technology implants an artificial heart valve into the native mitral valve of the heart to replace the native mitral valve and restore its function. The interventional surgery does not require thoracotomy, has small trauma, and fast postoperative recovery. It provides a new treatment method for high-risk patients of surgical operation, and can prolong the life of patients.

[0003] However, in the related art, there are some problems: the left heart pressure and the movement amplitude are large, the replaced valve prosthesis is prone to have insufficient matching with the atrium, and is prone to displacement; and the valve prosthesis structure is too long or penetrates into the left ventricle too much, affecting the function of the left ventricular outflow tract and causing left ventricular outflow tract obstruction. SUMMARY

[0004] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application provides a valve stent, which comprises an inner stent, a plurality of first stents, and a valve annulus matching portion; the plurality of first stents form a space with a spherical or spherical-like shape for supporting the atrium, which can avoid displacement of the valve stent in the forward-backward, left-right, and up-down directions during heartbeats, and at the same time, the valve annulus matching portion matches with the valve annulus, and the valve prosthesis is supported at the valve annulus by the radial support force of the valve annulus matching portion, further avoiding deflection and displacement of the valve prosthesis. Through the arrangement of the first stents and the valve annulus matching portion, reliable fixation of the valve prosthesis after implantation is achieved.

[0005] The present application also provides a valve prosthesis system.

[0006] The valve stent according to the first aspect of the present application comprises: an inner stent, a plurality of first stents, and a valve annulus matching portion; the plurality of first stents are arranged along the axial direction of the valve stent, the outflow ends of the first stents are connected to the outside of the inner stent through the valve annulus matching portion, and the plurality of first stents and the valve annulus matching portion are arranged along the circumferential direction of the inner stent; when the first stents are in an expanded state, the middle part of each first stent protrudes radially outward along the axial direction of the valve stent; the plurality of first stents form a space with a spherical or spherical-like shape for supporting the atrium; and the valve annulus matching portion is used for matching with the valve annulus.

[0007] The valve prosthesis according to the embodiments of the present application, the plurality of first stents form a space with a spherical or spherical-like shape for supporting the atrium wall, which can avoid the valve prosthesis from moving in the front-back, left-right, and up-down directions and being displaced when the heart beats, and the valve annulus matching portion matches with the valve annulus, and the valve prosthesis is supported at the valve annulus by the radial supporting force of the valve annulus matching portion, which further avoids the valve prosthesis from being deflected and displaced. Through the two fixing mechanisms, reliable fixation of the valve prosthesis after implantation is achieved.

[0008] According to some embodiments of the present application, each first stent comprises: a first rod segment and a second rod segment, the first rod segment is closer to the inflow end of the valve stent than the second rod segment, the inflow ends of the first rod segments are close to each other, the outflow end of each first rod segment is connected to at least two second rod segments, one end of the second rod segment is connected to the first rod segment, and the other end of the second rod segment is connected to the valve annulus matching portion.

[0009] According to some embodiments of the present application, each first stent further comprises: a transition rod segment, the transition rod segment is connected between the first rod segment and the second rod segment; the outflow end of each first rod segment is connected to at least two transition rod segments, each transition rod segment is connected to at least two second rod segments, and / or the number of rows of transition rod segments along the circumferential direction of the valve stent is at least one row.

[0010] According to some embodiments of the present application, there are two transition rod segments connected to the same first rod segment, the outflow ends of the two transition rod segments are away from each other; there are two second rod segments connected to the same transition rod segment, the outflow ends of the two second rod segments are away from each other; and the valve annulus matching portion has a plurality of third rod segments, the outflow ends of the second rod segments of adjacent first stents are connected to the same third rod.

[0011] According to some embodiments of the present application, the first rod segment has a width of d1, the second rod segment has a width of d2, and the transition rod segment has a width of d3, and d1, d2 and d3 satisfy the relationship: d1>d3>d2, and / or the axial length of the first rod segment is not less than 1 / 2 of the axial length of the first stent. According to some embodiments of the present application, the annulus matching portion comprises: a third rod segment connected between the second rod segment and one end of the fourth rod segment, and the other end of the fourth rod segment is connected to the inner stent, the third rod segment is arranged along the axial direction of an annulus, or the third rod segment is arranged at an angle with the axial direction of an annulus; and / or the fourth rod segment extends along the radial direction of the inner stent, or the fourth rod segment is arranged at an angle with the radial direction of the inner stent.

[0012] According to some embodiments of the present application, the second rod segment has a width of d2, and the transition rod segment has a width of d3, and d1, d2 and d3 satisfy the relationship: d1>d3>d2.

[0013] According to some embodiments of the present application, the sum of the heights of the second rod segment and the third rod segment is h1, and the height of the inner stent is h2, and h1 and h2 satisfy the relationship: h1≤h2.

[0014] According to some embodiments of the present application, the inner stent comprises: a plurality of grid frames, and the grid frames are divided by the connections between adjacent two grid frames, and each grid frame comprises: a fifth rod segment and a sixth rod segment in the axial direction, the height of the fifth rod segment is h3, the height of the sixth rod segment is h4, and the height of the second rod segment is h5, and h3, h4 and h5 satisfy the relationship: h3

[0015] According to some embodiments of the present application, the annulus matching portion has a size H in the axial direction of the valve stent, and the H is 0.6 to 2 times the axial size of an annulus.

[0016] According to some embodiments of the second aspect of the present application, the valve prosthesis system comprises: a valve prosthesis and a delivery assembly, the valve prosthesis comprises a valve stent, valve leaflets and a skirt, the valve leaflets are fixed to the inner stent, and the skirt is wrapped on the inner surface and / or the outer surface of the valve stent; the delivery assembly comprises: a delivery sheath and a guide wire, and the delivery sheath is provided with a delivery cavity for loading and delivering the valve prosthesis.

[0017] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and the attendant drawings or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0018] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, including the accompanying drawings, wherein:

[0019] Figure 1 is a schematic view of a valve prosthesis according to the present application implanted in a left atrium;

[0020] Figure 2 is a schematic view of a structure of a valve prosthesis according to the present application;

[0021] Figure 3 is a top view of a valve prosthesis according to the present application;

[0022] Figure 4 is a front view of a valve prosthesis according to the present application with skirt removed;

[0023] Figure 5 is a schematic view of a structure of a valve stent according to the present application;

[0024] Figure 6 is a schematic view of a structure of an inner stent according to the present application;

[0025] Figure 7 is a schematic view of a valve prosthesis according to an embodiment of the present application immediately after implantation in a right atrium;

[0026] Figure 8 is a schematic view of a valve prosthesis according to an embodiment of the present application as it enters a left ventricle from a left atrium and valve annulus.

[0027] REFERENCE NUMERALS:

[0028] 100, valve prosthesis;

[0029] 10, valve stent;

[0030] 11, outer stent; 111, atrium matching portion; 112, first stent; 113, first rod segment; 114, transition rod segment; 115, second rod segment; 116, valve annulus matching portion; 117, second rod; 118, third rod segment; 119, fourth rod segment;

[0031] 12, inner stent; 121, mesh stent; 122, fifth rod segment; 123, sixth rod segment; 124, leaflet connecting segment;

[0032] 21, leaflet; 22, skirt; 23, valve annulus; atrium wall 24; 25, left atrium;

[0033] 210 delivery sheath; 220 guidewire. DETAILED DESCRIPTION

[0034] Embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0035] Reference is made below to Figures 1-8 A valve prosthesis system having the valve prosthesis 100 is also provided.

[0036] The valve prosthesis 100 can be used to replace native valve structures such as mitral valves, tricuspid valves, aortic valves and pulmonary valves. The outflow end and the inflow end in this context refer to the outflow end and the inflow end of blood.

[0037] In combination with Figures 1-5 As shown in the drawings, a valve prosthesis 100 is provided according to an embodiment of the present application, which comprises a valve stent 10, valve leaflets 21 and a skirt 22. A valve stent 10 is also provided according to an embodiment of the present application. The valve stent 10 comprises an outer stent 11 and an inner stent 12, and the outer stent 11 is connected to the inner stent 12 and located at the outer periphery of the inner stent 12.

[0038] The valve stent 10 is the main structure of the valve prosthesis 100, the valve leaflets 21 are fixed to the inner stent 12 and are supported by the inner stent 12, the skirt 22 is wrapped around the inner surface and / or the outer surface of the valve stent 10 and is supported by at least one of the outer stent 11 and the inner stent 12, and the outer stent 11 is used to install, position and fix the valve prosthesis 100 in the left atrium 25 and at the annulus 23 of the native mitral valve. In addition, the outer stent 11 and the inner stent 12 can be made by integral processing, such as cutting a pipe or weaving a wire, and then being shaped by a heat treatment process to form the valve stent 10, or can be made by separate processing, i.e. the outer stent 11 and the inner stent 12 are made separately and then connected by welding and / or riveting to form the valve stent 10.

[0039] The leaflets 21 can simulate the native leaflets to achieve the function of closing during left ventricular contraction and opening during diastole, replacing the function of the native leaflets. Alternatively, the leaflets 21 are prepared from animal-derived pericardial tissue, preferably porcine pericardial tissue or bovine pericardial tissue, which is inactivated, anti-calcified, and the like, and then sutured to the valve stent 10. Alternatively, the leaflets 21 are prepared from animal-derived valve tissue, such as porcine aortic valve tissue or porcine pulmonary valve tissue. Alternatively, the leaflets 21 are prepared from biocompatible polymers, such as polyethylene terephthalate, polytetrafluoroethylene, polyethylene, and the like, which are simpler in process treatment than animal-derived tissue and more convenient in production and preparation.

[0040] As shown in Figure 3 and Figure 4 , the leaflets 21 are in a leaflet structure, and three leaflets 21 are sutured to the inner stent 12 by a suturing process. The three leaflets 21 cooperate with each other to have a good fluid dynamics effect, so that the blood flow dynamics is more stable when the leaflets 21 open and close. Alternatively, the leaflets 21 can also be two, which is the same as the number of native mitral valve leaflets. Alternatively, the leaflets 21 can also be four or more, which can be set according to actual needs. In addition to the suturing method, the leaflets 21 can also be fixed to the inner stent 12 by other methods, such as bonding or welding.

[0041] The skirt 22 is used to achieve a sealing function to ensure that the passage of blood from the left atrium 25 into the left ventricle is only through the passage after the leaflets 21 are opened, preventing blood from leaking from the side of the valve prosthesis 100 or from the inside of the valve prosthesis 100, or from the gap between the stent mesh of the valve stent 10, the outer stent, and the inner stent of the artificial leaflet, affecting the blood flow dynamics effect of the valve prosthesis 100.

[0042] As shown in Figures 1-3 , the skirt 22 covers the outer surface of the outer stent 11 and the inner surface of the inner stent 12 to prevent blood leakage. That is, by arranging the skirt 22 on the outer surface of the outer stent 11 and the inner surface of the inner stent 12, blood leakage from the outer stent 11, the inner stent 12, and the gap between the outer stent 11 and the inner stent 12 can be prevented, affecting the blood flow dynamics effect of the interventional valve prosthesis 100, and ensuring that the passage of blood from the left atrium 25 into the left ventricle is only through the passage after the leaflets 21 are opened.

[0043] The skirt 22 can be made of animal-derived pericardial tissue or made of biocompatible polymers such as polyethylene terephthalate, polytetrafluoroethylene or expanded polytetrafluoroethylene. The skirt 22 is sutured to the valve stent 10 and the leaflets 21 to prevent blood leakage from the gaps of the valve stent 10 mesh and the gap between the outer stent 11 and the inner stent 12, thus ensuring good hemodynamics. At the same time, the surface of the skirt 22 has a microporous structure, which is conducive to the coverage of human endothelial cells, can accelerate the endothelialization of the valve prosthesis 100, is conducive to the long-term fixation of the valve prosthesis 100, and can also improve the thrombosis of the valve prosthesis 100. Alternatively, the skirt 22 can be attached to the valve stent 10 by heat fusion.

[0044] As Figure 5As shown, the outer stent 11 comprises an atrium matching portion 111 and an annulus matching portion 116 arranged at the outflow end of the atrium matching portion 111. The atrium matching portion comprises a plurality of first stents 112 arranged along the axial direction of the valve stent 12, the outflow end of the first stent 112 is connected to the outside of the inner stent 12 through the annulus matching portion 116, and the plurality of first stents 112 and the annulus matching portion 116 are arranged along the circumferential direction of the inner stent 12; when the first stent 112 is in the expanded state, the middle part of the single first stent 112 protrudes radially outward along the axial direction of the valve stent 12; the plurality of first stents 112 form a space with a spherical or spherical-like shape to match the shape of the left atrium 25, for supporting the atrium, so that the atrium matching portion 111 is supported on the atrial wall 24 in a spherical or spherical-like form, thereby achieving fixation of the valve prosthesis 100 in the left atrium 25. Specifically, the spherical or spherical-like atrium matching portion 111 cooperates with the atrial wall 24, and the two are in contact with each other, which can ensure that the atrium matching portion 111 effectively abuts and supports on the atrial wall 24 during heartbeats, avoiding displacement of the valve prosthesis 100 in the forward, backward, left, right, upward and downward directions, so that the valve prosthesis 100 is reliably fixed in the left atrium 25. At the same time, the annulus matching portion 116 matches the annulus 23 of the native mitral valve, specifically, the annulus matching portion 116 has a circular or circular-like structure, and the outer periphery of the annulus matching portion 116 abuts against the inner wall of the annulus 23, and the radial support force of the annulus matching portion 116 achieves positioning of the valve prosthesis 100 and prevents the valve prosthesis 100 from being deflected. In this way, when the valve prosthesis 100 is located in the left atrium 25, the atrium matching portion 111 and the atrial wall 24 are in contact with each other, which achieves fixation of the valve prosthesis 100 in the left atrium 25 and avoids twisting and displacement during heartbeats. At the same time, the annulus matching portion 116 cooperates with the annulus 23 and the native leaflet, and the radial support force of the annulus matching portion 116 supports the valve prosthesis 100 at the annulus 23, further avoiding deflection and displacement of the valve prosthesis 100. The annulus matching portion 116 can also clamp the native leaflet around the outer periphery of the annulus matching portion 116 to prevent the native leaflet from blocking blood flow at the annulus. In this way, through the two forms of the plurality of first stents 112 and the annulus matching portion 116 of the outer stent 11, the valve prosthesis 100 relies on two fixation mechanisms to achieve reliable fixation after implantation.

[0045] The atrial matching portion 111 comprises a plurality of first supports 112, which are distributed along the circumference of the inner support 12, for example, preferably, the plurality of first supports 112 can be sequentially connected along the circumference to form a spherical or spherical-like atrial matching portion 111, the plurality of first supports 112 abut against the atrial wall 24, and rely on the support of the atrial wall 24 to avoid the valve prosthesis 100 from moving in the front-back, left-right, up-down direction, so that the valve prosthesis 100 can be reliably fixed in the left atrium 25. Wherein, the number of first supports 112 can be between 3-15, and in the embodiment of the present application, there are 6. It should be understood that the plurality of first supports 112 can be two, three or four first supports.

[0046] Preferably, each first strut 112 comprises a first bar segment 113 and at least two second bar segments 115, the first bar segment 113 is closer to the inflow end of the valve stent 10 than the second bar segments 115, the inflow ends of the first bar segments 113 are close to each other, the outflow end of each first bar segment 113 is connected with at least two second bar segments 115, one end of the second bar segment 115 is connected to the first bar segment 113, and the other end of the second bar segment 115 is connected to the annulus matching part 116. In this way, compared with the outer stent of the valve stent in the prior art, each first strut 112 in the outer stent of the embodiment has only one first bar segment 113 close to the inflow end, which has three advantages: 1. The side of the valve stent close to the outflow end has a relatively sparse structure. That is, in the upper half of the valve stent close to the outflow end, the first bar segment 113 of the first strut 112 is a single strut, which is relatively soft. During delivery, it can bend 90° in the blood vessel, avoiding the possibility of turning over of the valve stent during delivery. 2. The mesh of the first bar segment 113 is sparse, the contact area between the first strut 112 and the atrium is small, and the probability of blocking the blood vessel is small. 3. When performing secondary puncture, the space between the first struts 112 in the atrium is large, and the resistance to secondary puncture is small. Preferably, the second bar segments 115 of a plurality of first struts 112 are connected to the bar segments of the same annulus matching part 116 to realize the connection of the first struts 112 in the circumferential direction. That is, each first bar segment 113 is connected with at least two second bar segments 115, and adjacent two second bar segments 115 are connected in the circumferential direction, wherein the number of first bar segments 113 is consistent with the number of first struts 112, that is, the number of first bar segments 113 is 3-15, and the number of first bar segments 113 is preferably 6 in the embodiment of the application. Preferably, the axial length of the first bar segment 113 is not less than 1 / 2 of the axial length of the first strut 112. More preferably, the axial length of the first bar segment 113 is equal to 1 / 2 of the axial length of the first strut 112, so that the first bar segment 113 can occupy half of the atrium, thereby further reducing the structure of the valve stent 10 in the atrium. In addition, the bar width of the first bar segment 113 is the largest in the entire valve stent 10, and the bar width d1 of the first bar segment 113 is preferably 0.5-3 mm, for example. Through the number, bar width and length of the first bar segment 113, the number and bar width of the first bar segment 113 cooperate and synergize with each other, so that the valve prosthesis 100 has the flexibility of being able to support the atrium in the expanded state and being able to contract in the contracted state under the action of the first bar segment 113 and the second bar segment 115.

[0047] Specifically, in the expanded state, the number of first bar segments 113 is not too small, so that the outer stent 11 can form a spherical or spherical-like support in the left atrium 25, and as shown inFigure 1 As shown, the number of first rod segments 113 is not too large, that is, the first rod segments 113 are relatively sparse as a whole, which can prevent the valve prosthesis 100 from blocking the pulmonary vein after endothelialization and affecting the blood flow path of the pulmonary vein. In addition, during the suturing process of the valve leaflets 21, the sparse first rod segments 113 have less obstruction to the suturing operation, making it easier for the needle and thread to pass through the sparse first rod segments 113 to suturing the valve leaflets 21 and the inner support 12. Furthermore, the rod width of the first rod segment 113 is greater than the rod width of the second rod segment 113, so that each first rod segment 113 has a certain rigidity and thus a certain supporting force, which can ensure that when the heart beats, each first rod segment 113 is effectively supported on the atrial wall 24, so that the entire valve prosthesis 100 is supported by the atrial wall 24, and the valve prosthesis 100 is prevented from moving or shifting.

[0048] like Figure 7 and Figure 8 As shown, the valve prosthesis 100 is suitable for delivery to the left atrium 25 via the delivery sheath 210 in a contracted state. In the contracted state, all first rod segments 113 of the valve prosthesis 100 are arranged roughly along the axial direction of the valve prosthesis 100 and merge to form a cylindrical structure. The aforementioned setting of the rod width of the first rod segments 113 gives each first rod segment 113 a certain rigidity relative to the contraction and expansion of the atrial wall 24 during heart beats. In fact, each first rod segment 113 can still bend under the action of a large external force due to the rod width designed by the present invention. Furthermore, the number of first rod segments 113 is relatively small. Although the whole formed by all the first rod segments 113 is rigidly superimposed, it still has a certain flexibility and is easy to bend, with good bending performance. In this way, the valve prosthesis 100 is inside the bendable delivery sheath 210, and the whole formed by all the first rod segments 113 can bend, which has little impact on the performance of the bendable delivery sheath 210, making it easier for the valve prosthesis 100 to pass through the curved blood vessel path and the atrial septum into the left atrium 25 along with the delivery sheath 210, and avoiding damage to the blood vessel wall during delivery. More importantly, by rationally designing the number and rod width of the first rod segments 113, the whole formed by all the first rod segments 113 has sufficient flexibility to withstand bending close to 90 degrees. Figure 8As shown, by bending close to 90°, the annulus matching part 116 can be aligned with the annulus 23, so that after the valve prosthesis 100 is deployed, the annulus matching part 116 can be aligned with the annulus 23. It should be noted that after the valve prosthesis 100 is deployed, the outer stent 11 matches the heart cavity of the left atrium 25, and it is difficult to adjust the position of the valve prosthesis 100. In the present application, when the valve prosthesis 100 is in a contracted state, the first rod segment 113 can be bent close to 90° to realize the alignment of the annulus matching part 116, avoid inaccurate positioning when released, so as to ensure that the annulus matching part 116 is released in the annulus 23, and the annulus matching part 116 is matched with the annulus 23 after being deployed. In addition, after the annulus matching part 116 is matched with the annulus 23, the installation of the rest of the valve prosthesis 100 can be positioned to ensure that the valve prosthesis 100 is installed in place. Moreover, the deflection force generated by the first rod segment 113 on the annulus 23 during release and deployment is small, and once positioned, the valve prosthesis 100 will not be skewed or displaced.

[0049] Please refer again to Figure 1 and Figure 5 The number of the second rod segments 115 is 2-6 times the number of the first rod segments 113. In the embodiment of the present application, there are 24, which is 4 times the number of the first rod segments 113, that is, the other end of each first rod segment 113 is connected with 4 second rod segments 115. In addition, the rod width d2 of the second rod segment 115 is 0.1-0.8mm, and d2

[0050] In the embodiment of the present application, the second rod segment 115 is arranged in one row. It can be understood that the second rod segment 115 can also be arranged in two or three rows. However, it should not exceed three rows, so as not to affect the compliance. In addition, the number of the second rod segment 115 refers to the number of one row.

[0051] Each first support 112 further comprises a transition rod segment 114 connected between the first rod segment 113 and the second rod segment 115. The outflow end of each first rod segment 113 is connected with at least two transition rod segments 114, and each transition rod segment is connected with at least two second rod segments 115. The transition through the transition rod segment 114 can avoid the occurrence of isolated rod segments or nodes, thereby ensuring the closed loop envelope of the entire outer support 11. In the embodiment of the present application, the number of transition rod segments 114 is 12, so that each first rod segment 113 corresponds to two transition rod segments 114, and each of the two transition rod segments 114 corresponds to two second rod segments 115, respectively, thereby avoiding the occurrence of isolated rod segments or nodes. The transition rod segment 114 serves as a connecting rod segment between the first rod segment 113 and the second rod segment 115, which needs to have a certain rigidity on the one hand to ensure good support performance, and needs to have a certain flexibility on the other hand, so that it can gradually conform to the atrial wall 24 in the direction close to the second rod segment 115. Therefore, the rod width d3 of the transition rod segment 114 is designed to be 0.2-1mm, and d1>d3>d2. The number of transition rod segments 114 is adaptively adjusted according to the number of first rod segments 113 and second rod segments 115, so as to avoid the occurrence of isolated rod segments or nodes.

[0052] Further, the number of rows of transition rod segments 114 along the circumference of the valve support 10 is at least one row. As shown in the drawings, the transition rod segment 114 is preferably one row, and further along the circumference of the valve support 10, so that the first rod segment 113, the second rod segment 115 and the transition rod segment 114 are all arranged in one row, thereby ensuring the simple structure of the valve support 10 and the support rigidity. In other embodiments, the transition rod segment 114 can also be arranged in two rows or three rows according to actual needs. Figure 5

[0053] ​The height of the valve ring matching portion 116 is H, and H is 0.6 to 2 times the axial dimension of a valve ring. Preferably, it is 1.2 to 1.5 times, so that the valve ring matching portion 116 can be better stuck in the position of the valve ring 23. For example, preferably, H satisfies the relationship: 5≤H≤15mm. That is to say, the axial dimension of the valve ring matching portion 116 is H, and is set between 5-15mm, so that the valve ring matching portion 116 not only cooperates with the valve ring 23, but also partially passes through the valve ring 23 and extends into the left ventricle to cooperate with the native leaflet. The valve ring matching portion 116 partially extends into the left ventricle, which can ensure that when the valve prosthesis 100 is released, the valve ring matching portion 116 first cooperates with the valve ring 23, providing a pre-positioning function to avoid the rest of the valve prosthesis 100 from shifting or skewing during the release and deployment process, affecting the final implantation effect. After implantation, the annulus matching portion 116 partially extends into the left ventricle, thereby enhancing the fixation of the valve prosthesis 100. Furthermore, the partial extension of the annulus matching portion 116 into the left ventricle can push aside the native valve leaflets, restricting their movement and preventing their interference with the operation of the valve prosthesis 100. For example, this prevents the valve prosthesis 100 and the native leaflets from operating simultaneously and causing hemodynamic disturbances. Furthermore, as previously described, the valve prosthesis 100 employs two fixation mechanisms. If the atrial matching portion 111 also serves as a fixation mechanism, the annulus matching portion 116 does not need to extend excessively into the left ventricle. The main structure of the valve prosthesis 100 is located within the left atrium 25, and the annulus matching portion 116 extends shallowly into the left ventricle, ensuring that the native leaflets are pushed aside without affecting the function of the left ventricular outflow tract and thus preventing left ventricular outflow tract obstruction.

[0054] like Figure 1 and Figure 5 As shown, the valve ring matching portion 116 matches the valve ring 23 , is connected to the second rod segment 115 , and is connected to the inner support 12 to form a connecting section between the outer support 11 and the inner support 12 .

[0055] The annulus matching part 116 comprises a plurality of second struts 117 distributed in the circumferential direction. The number of the second struts 117 can be 6-24. The second strut 117 comprises a third strut segment 118 connected between the second strut segment 115 and one end of a fourth strut segment 119, and the other end of the fourth strut segment 119 is connected to the inner stent 12. The third strut segment 118 extends along the axial direction of the inner stent 12, and the fourth strut segment 119 extends along the radial direction of the inner stent 12. That is, after the valve prosthesis 100 is implanted, the third strut segment 118 matches the annulus 23, so that the valve prosthesis 100 can be fixed at the annulus 23, and the outer stent 11 and the inner stent 12 are fixedly connected by the fourth strut segment 119. The strut width d4 of the third strut segment 118 is 0.3-0.8 mm, so that the third strut segment 118 has sufficient radial support force to resist the annulus 23.

[0056] In the embodiment of the application, the number of the second struts 117 is 12, one second strut 117 is connected at each node of every two connected second strut segments 115, and the second strut 117 comprises a third strut segment 118 and a fourth strut segment 119. Preferably, there are two transition strut segments 114 connected to the same first strut segment 113, the outflow ends of the two transition strut segments are away from each other and extend in a direction away from each other. There are two second strut segments 115 connected to the same transition strut segment 114, the outflow ends of the two second strut segments are away from each other and extend in a direction away from each other, the end portions of two adjacent second strut segments 115 located on two different transition strut segments 114 are connected, and the two adjacent second strut segments 115 are connected to the third strut segment 118 of one annulus matching part, so that the annulus matching part 116 has relatively high rigidity to support the annulus. That is, the number of the third strut segments 118 is half of the number of the second strut segments 115, i.e. the number of the third strut segments 118 is 12, and the number of the fourth strut segments 119 is also 12, the third strut segment 118 corresponds to the fourth strut segment 119 one by one, the number of the second struts 117 is small, and the second struts 117 are far apart from each other, which is beneficial to bending and forming the second struts 117 into an L-shaped annulus matching part 116 during processing of the valve stent 10, facilitating connection of the annulus matching part 116 with the inner stent 12, and facilitating abutment of the annulus matching part 116 with the annulus 23.

[0057] Preferably, the annulus matching portion 116 comprises a third bar segment 118 and a fourth bar segment 119. The third bar segment 118 is connected between the second bar segment 115 and one end of the fourth bar segment 119, and the other end of the fourth bar segment 119 is connected to the inner stent 12. The third bar segment 118 is arranged along the axial direction of the annulus 23, or the third bar segment 118 is arranged at an angle with the axial direction of the annulus 23. That is, the third bar segment 118 is, for example, a support rib, which is arranged along the axial direction, and a plurality of third bar segments 118 are arranged in a ring shape, thereby achieving the effect of supporting the annulus 23. In the preferred embodiment, the third bar segment 118 is arranged at an angle with the axial direction of the valve stent 10, that is, the outflow end of the third bar segment 118 is inclined toward the radial direction outward of the valve stent 10, for example, the angle is less than 45°, preferably 15°. The inclination angles of all the third bar segments 118 arranged in the circumferential direction are consistent, so that the outer periphery of the annulus matching portion 116 presents a flared shape, the direction of the flaring is toward the outflow end, further enabling the annulus matching portion 116 to firmly hold the annulus 23 and prevent loosening. It should be understood that the third bar segment 118 and the fourth bar segment 119 are not limited to straight bars, but can also be bars with curvature, and the curvature can be matched with the curvature of the annulus. Preferably, when the third bar segment 118 is arranged at an angle with the axial direction of the valve stent 10, the curvature of the third bar segment 118 is concave toward the radial direction inward of the valve stent 10 to match the structure of the annulus 23.

[0058] Furthermore, the fourth bar segment 119 extends along the radial direction of the inner stent 12, for example, the annulus matching portion 116 is arranged in an L shape, thereby enabling the third bar segment 118 to be arranged at a distance from the inner stent. Alternatively, the fourth bar segment 119 is arranged at an angle with the radial direction of the inner stent 12, for example, the annulus matching portion 116 is arranged in an arc shape, thereby further matching the structure of the annulus 23. In addition, the third bar segment 118 is arranged at an angle θ of 90°-180°, but not including 180°, with respect to the fourth bar segment 119, so as to adapt to the annulus 23. Moreover, the connection between the third bar segment 118 and the fourth bar segment 119 is rounded, so that the transition is smooth and a sharp protrusion is avoided, thereby effectively avoiding damage to the tissue. Preferably, the radius of the rounding is 1-2 mm.

[0059] Referring to Figure 5As shown, the sum of the heights of the second segments 115 and the second struts 117 is h1, and the height of the inner stent 12 is h2. h1 and h2 satisfy the relationship: h1 ≤ h2. Thus, when the valve prosthesis 100 is pressed against the delivery sheath 210, that is, when the valve prosthesis 100 is in a compressed state, the second segments 115 and the second struts 117 overlap with the inner stent 12. Although each second segment 115 is relatively flexible, the large number of second segments 115, when combined into a whole, creates a rigid, inflexible portion A. The inner stent 12, which supports the leaflets 21, requires significant rigidity. After the valve prosthesis 100 is compressed, the inner stent 12 forms a relatively rigid, inflexible portion B. It should be noted that the inner stent 12 needs to have an appropriate height based on the leaflets 21, meaning that the height of the inflexible portion B is difficult to adjust. In this way, in order to minimize the axial rigid part and maximize the axially flexible part of the valve prosthesis 100 when it is in a compressed state, the non-bendable part B needs to cover the non-bendable part A in the axial direction, and thus, h1≤h2 needs to be achieved.

[0060] The outer stent 11 can be made by cutting a tube or braiding a wire. The outer stent 11 is preferably made of nickel-titanium shape memory alloy and is shaped into a spherical or spherical shape by utilizing its characteristics.

[0061] like Figure 6 As shown, the inner stent 12 includes: a plurality of grid frames 121, which are arranged and connected in an array in the circumferential direction and form a cylindrical or conical shape. In other words, the inner stent 12 is a support frame composed of a plurality of grid frames 121, and its outline shape is cylindrical or conical. In addition, at least a portion of the grid frames 121 is provided with a fixing interface for fixing the leaflets 21, and the leaflets 21 are sutured through the fixing interface, and support is provided for the opening and closing movement of the leaflets 21. Among them, the grid frame 121 is a quadrilateral structure, and designing the grid frame 121 as a quadrilateral is conducive to the compression and expansion of the inner stent 12.

[0062] Among them, the inner bracket 12 includes at least three rows of grid frames 121 along the axial direction. In this embodiment, the inner bracket 12 includes three rows of grid frames 121 along the axial direction, and each row is composed of 12 circumferentially distributed grid frames 121. It can be understood that in other embodiments not shown, the number of rows of grid frames 121 and the number of each row can be adjusted according to actual usage requirements.

[0063] Further, if Figure 6As shown, the grid frame 121 includes, in the axial direction, a fifth rod segment 122 and a sixth rod segment 123, with the grid frame 121 being a quadrilateral structure. Designing the grid frame 121 as a quadrilateral is conducive to the compression and expansion of the inner support 12. Each grid frame 121 includes two fifth rod segments 122 and two sixth rod segments 123. Since the inner support 12 includes at least three rows of grid frames 121 connected in an array in the circumferential direction, the adjacent two rows of grid frames 121 share a side, for example, the sixth rod segment 123 of the grid frame 121 of the first row is the fifth rod segment 122 of the grid frame 121 of the second row. For the sake of description and understanding, for a single grid frame 121, the upper one is the fifth rod segment 122 and the lower one is the sixth rod segment 123. The upper ends of the two fifth rod segments 122 are connected to each other, the lower ends of the two sixth rod segments 123 are connected to each other, and the lower end of the fifth rod segment 122 is connected to the upper end of the corresponding sixth rod segment 123. The fourth rod segment 119 corresponds to the grid frame 121 of the lowermost row and is connected to the lower ends of the corresponding two sixth rod segments 123.

[0064] As shown in Figure 6 , the height of the fifth rod segment 122 is h3, the height of the sixth rod segment 123 is h4, and the height of the second rod segment 115 is h5. h3, h4, and h5 satisfy the relationship h3 < h5, h4 < h5. That is, the axial dimension of the fifth rod segment 122 and the sixth rod segment 123 is smaller than the axial dimension of the second rod segment 115, so as to ensure that the inner support 12 has high rigidity and provides sufficient support to the leaflet 21. Understandably, the height of the fifth rod segment 122 and the sixth rod segment 123 can represent the length of a single grid in the axial direction of the valve stent 10. In addition, the axial dimensions of the fifth rod segment 122 and the sixth rod segment 123 can be set to be equal or unequal.

[0065] In addition, the width of the fifth rod segment 122 is d5, the width of the sixth rod segment 123 is d6, and the width of the second rod segment 115 is d2. d2, d5, and d6 satisfy the relationship d2 < d5, d2 < d6. That is, the rod width of the fifth rod segment 122 and the rod width of the sixth rod segment 123 are greater than the rod width of the second rod segment 115, so that the grid frame 121 constitutes an inner support 12 with good rigidity and strength, which has sufficient stability to support the movement of the leaflet 21, avoids the substantial deformation of the inner support 12 when the leaflet 21 moves, and ensures the normal opening, closing, and fluid dynamics of the leaflet 21. The rod width of the fifth rod segment 122 and the rod width of the sixth rod segment 123 can be equal or unequal, and the rod widths d5 and d6 are both between 0.3-1 mm.

[0066] In addition, in combination with Figure 4 and 6As shown, the inner stent 12 is further provided with a leaflet connecting segment 124 on the side away from the fourth rod segment 119 in the axial direction, and the leaflet 21 is fixed on the leaflet connecting segment 124. Specifically, the part between the node where the two fifth rod segments 122 of the first row of lattice frames 121 of the inner stent 12 are connected and the fixed interface is the leaflet connecting segment 124. The axial dimension of the leaflet connecting segment 124 is h6, and in this embodiment, the contour of the inner stent 12 is cylindrical, and the radial dimension of the inner stent 12 is D1, h6 satisfies the relationship: 8mm≤h6≤20mm, and D1 satisfies the relationship: 21mm≤D1≤34mm. In this way, the size conforms to the human anatomy and the size of the native leaflet, that is, the valve prosthesis 100 can conveniently realize the function of the native mitral valve.

[0067] The inner stent 12 can be prepared by cutting a pipe material or can be manufactured by weaving a wire material. The material of the inner stent 12 is preferably a nickel-titanium shape memory alloy, which is shaped into a corresponding shape by using its characteristics. The material of the inner stent 12 can also be selected from materials with good biocompatibility such as cobalt-chromium alloy, stainless steel, titanium alloy, etc.

[0068] According to the valve prosthesis system of the second embodiment of the present application, the valve prosthesis system comprises a valve prosthesis 100 and a delivery assembly. The valve prosthesis 100 comprises the valve stent 10, the skirt 22 and the leaflet 21 described above. The delivery assembly comprises a delivery sheath 210 and a guide wire 220, and the delivery sheath 210 is provided with a delivery cavity for loading and delivering the valve prosthesis 100.

[0069] Before the valve prosthesis 100 is implanted, a delivery interface is designed on the valve stent 10, and a delivery member (not shown in the figure) is connected to the delivery interface. Then, the valve prosthesis 100 is compressed and gathered together with the guide wire 220 and the delivery member and loaded in the delivery cavity. It can be understood that the delivery cavity can be one cavity or multiple cavities, and when the delivery cavity is multiple cavities, the valve prosthesis 100, the guide wire 220 and the delivery member can be loaded in different cavities.

[0070] In combination with Figure 7 and Figure 8 As shown, first, the guide wire 220 is used to establish a delivery path from the blood vessel to the left ventricle, and the delivery sheath 210 is guided and supported by the guide wire 220 to deliver the valve prosthesis 100 along the guide wire 220 to the right atrium. Then, the first rod segment 113 is bent to facilitate the valve prosthesis 100 to extend into the left atrium 25. Then, after entering the left atrium 25, the first rod segment 113 is bent again by about 90° to make the annulus matching part 116 opposite to the annulus 23. Then, the valve prosthesis 100 passes through the annulus 23 and partially extends into the left ventricle. Subsequently, the delivery member pushes the valve prosthesis 100 out of the delivery cavity to release the valve prosthesis 100, and the valve prosthesis 100 expands and unfolds. Finally, the delivery sheath 210, the delivery member and the guide wire 220 and other related parts of the delivery assembly are removed.

[0071] In the description of the application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0072] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example" or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.

[0073] Although embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A valve stent, characterized by, The valve stent comprises: an inner stent, a plurality of first stents and a valve annulus matching part; the plurality of first stents are arranged along the axial direction of the valve stent, the outflow ends of the first stents are connected to the outside of the inner stent through the valve annulus matching part, and the plurality of first stents and the valve annulus matching part are arranged along the circumferential direction of the inner stent; when the first stents are in an expanded state, the middle part of each first stent protrudes radially outward along the axial direction of the valve stent, and the plurality of first stents form a space with a spherical or spherical-like shape for supporting the atrium; the valve annulus matching part is used for matching with a valve annulus; each first stent comprises a first rod segment and a second rod segment, the first rod segment is closer to the inflow end of the valve stent than the second rod segment, the inflow ends of the first rod segments are close to each other, the outflow end of each first rod segment is connected to at least two second rod segments, one end of the second rod segment is connected to the first rod segment, and the other end of the second rod segment is connected to the valve annulus matching part; the valve stent has a relatively sparse mesh structure at the position corresponding to the first rod segment, and the valve stent has a relatively dense mesh structure at the position corresponding to the second rod segment.

2. The valve support of claim 1, wherein, each first stent further comprises a transition rod segment connected between the first rod segment and the second rod segment; the outflow end of each first rod segment is connected to at least two transition rod segments, each transition rod segment is connected to at least two second rod segments, and / or the number of rows of transition rod segments along the circumferential direction of the valve stent is at least one row.

3. The valve support of claim 2, wherein, the transition rod segments connected to the same first rod segment are two, and the outflow ends of the two transition rod segments are away from each other; the second rod segments connected to the same transition rod segment are two, and the outflow ends of the two second rod segments are away from each other; and the valve annulus matching part has a plurality of third rod segments, and the outflow ends of the second rod segments of adjacent first stents are connected to the same third rod segment.

4. The valve support of claim 2, wherein, the width of the first rod segment is d1, the width of the second rod segment is d2, the width of the transition rod segment is d3, d1, d2 and d3 satisfy the relationship d1>d3>d2, and / or the length of the axial direction of the first rod segment is not less than 1 / 2 of the length of the axial direction of the first stent.

5. The valve support of claim 1, wherein, the valve annulus matching part comprises a third rod segment and a fourth rod segment, the third rod segment is connected between the second rod segment and one end of the fourth rod segment, and the other end of the fourth rod segment is connected to the inner stent, the third rod segment is arranged along the axial direction of a valve annulus, or the third rod segment is arranged at an angle with the axial direction of a valve annulus; and / or the fourth rod segment extends along the radial direction of the inner stent, or the fourth rod segment is arranged at an angle with the radial direction of the inner stent.

6. The valve support of claim 5, wherein, the total height of the second rod segment and the third rod segment is h1, the height of the inner stent is h2, and h1 and h2 satisfy the relationship h1≤h2.

7. The valve support of claim 5, wherein, The inner stent comprises a plurality of grid frames, and the grid frames are divided by the connection between two adjacent grid frames, and the grid frames in the axial direction comprise a fifth rod segment and a sixth rod segment, the height of the fifth rod segment is h3, the height of the sixth rod segment is h4, and the height of the second rod segment is h5, and h3, h4 and h5 satisfy the relationship: h3 < h5, h4 < h5; and / or, The width of the fifth rod segment is d5, the width of the sixth rod segment is d6, and the width of the second rod segment is d2, d3, d4 and d5 satisfy the relationship: d2 < d5, d2 < d6.

8. The valve support of claim 1, wherein, The size of the annulus matching part along the axial direction of the valve stent is H, and the H is 0.6 to 2 times the axial size of a valve annulus.

9. A valve prosthesis system comprising: Valve prosthesis and delivery assembly The valve prosthesis comprises the valve stent, the valve leaflet and the skirt of any one of claims 1-8. The valve leaflet is fixed to the inner stent, and the skirt is wrapped on the inner surface and / or the outer surface of the valve stent. The delivery assembly comprises a delivery sheath and a guide wire, and the delivery sheath is provided with a delivery cavity for loading and delivering the valve prosthesis.

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