Valve prosthesis
By designing the connection method between the inner and outer stents in the valve prosthesis, the deformation problem of the valve prosthesis during release was solved, resulting in better fixation and hemodynamic performance.
Patent Information
- Application Number
- CN202410819987.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-24
- Publication Date
- 2025-12-26
AI Technical Summary
Existing valve prostheses are prone to deformation when deployed to the target location, leading to paravalvular leakage.
A valve prosthesis was designed, comprising an inner stent and an outer stent. The leaflet is placed inside the inner stent, and the outer stent is connected to the inner stent to form multiple connection points that form a circle, ensuring the symmetrical structure and uniform stress of the stent body and preventing deformation and dislodgement.
With its symmetrical structure and uniform stress design, the valve prosthesis is less prone to deformation during compression and release, reducing paravalvular leakage and improving fixation performance and hemodynamic effects.
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Figure CN121196802A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of interventional medical device technology, and in particular to a valve prosthesis. Background Technology
[0002] The mitral valve, located in the left ventricle, acts as a valve between the left atrium and left ventricle, regulating blood flow and playing a vital role in the heart's circulatory system. The mitral valve leaflets consist of an anterior and posterior leaflets, with an arc-shaped, leaf-like structure. These leaflets are connected to the anterior and posterior papillary muscles via subvalvular chordae tendineae, controlling the opening and closing of the valve. Due to congenital abnormalities or acquired diseases, the mitral valve is prone to stenosis and regurgitation. The former reduces blood flow from the atrium to the ventricle, leading to pulmonary edema and heart failure, while the latter causes mitral regurgitation, resulting in pulmonary edema and heart failure. Mitral valve disease commonly occurs in elderly patients, with a high prevalence rate. Clinically, the common solution is to replace the diseased valve with an artificial heart valve.
[0003] With technological advancements and clinical demands, transcatheter mitral valve replacement (TMVR) is gradually becoming the future trend in artificial heart valve replacement technology. TMVR refers to an interventional procedure in which an artificial valve is compressed and loaded onto a delivery system outside the body, and then delivered along a vascular pathway or via the apex to the mitral valve annulus to replace the diseased valve. Due to the complexity of the mitral valve structure and ventricular hemodynamics, no mature product has yet been launched, and many TMVR procedures, both domestically and internationally, are still under research.
[0004] However, the valve is prone to deformation when it is released from the delivery system to the target location, which can easily lead to paravalvular leakage. Summary of the Invention
[0005] The present invention aims to provide at least one valve prosthesis that is not easily deformed after release.
[0006] This objective is achieved through the following technical solutions:
[0007] According to the technical solution of the present invention, a valve prosthesis is proposed, comprising a stent body and a leaflet. The stent body includes an outflow end and an inflow end, and includes an inner stent and an outer stent. The inner stent is disposed within the outer stent, and the leaflet is disposed within the inner stent. The outflow end includes multiple connection points. The outer stent and the inner stent are connected at or near the outflow end and then connected to the connection points. The multiple connection points form a circle, and the circle has a circumference. The multiple connection points equally divide the circumference.
[0008] The aforementioned valve prosthesis, by placing the inner stent layer within the outer stent layer and the leaflets within the inner stent layer, allows the outer stent layer to adhere to the tissue for fixation, preventing paravalvular leakage. Simultaneously, it ensures that the inner stent layer with leaflets is not compressed by the tissue, thus preventing interference with the leaflets' function. Furthermore, the outflow end includes multiple connection points. The outer and inner stent layers are connected at or near the outflow end and then connected to these connection points, forming a circle. This circle has a circumference, and the connection points equally divide the circumference. This ensures a symmetrical structure at the outflow end of the stent body, allowing for uniform compression and insertion into the delivery sheath, maintaining the stent body's compression and subsequent release state and preventing deformation. It also ensures even force distribution when the stent body is placed at the lesion site, thus reducing the likelihood of dislodgement.
[0009] In one embodiment, the outer support includes a first support portion and a second support portion connected axially. The plane at one end of the first support portion and the second support portion is perpendicular to the axis of the support body. The second support portion is connected to or near the outlet end of the inner support.
[0010] In one embodiment, the second support portion is connected to the first support portion at an angle, and the second support portion includes a plurality of support rods, the support rods including at least one of straight rods and curved rods.
[0011] In one embodiment, the second support portion includes a plurality of unit structures distributed circumferentially, each unit structure including a plurality of support rods, one end of which converges and connects to the same connection point, and the other ends of at least two of the plurality of support rods are respectively connected to different positions on the first support portion.
[0012] In one embodiment, the outer support includes a first support portion and a second support portion connected axially. The second support portion is connected to or near the outlet end of the inner support. The projection of the first support portion on a cross section perpendicular to the axis is D-shaped. The D-shape includes a first segment and a second segment connected circumferentially. The arc length of the first segment is greater than the arc length of the second segment. The portion of the first support portion corresponding to the first segment is a first part, and the portion of the first support portion corresponding to the second segment is a second part.
[0013] In one embodiment, the second support portion includes a plurality of unit structures distributed circumferentially. The unit structures include a first unit structure and a second unit structure with identical structures. The first unit structure is located at the middle position of the first portion, and the second unit structure is located at the middle position of the second portion. A third unit structure and a fourth unit structure are respectively arranged on both sides of the first unit structure. The third unit structure and the fourth unit structure are structurally symmetrical about the first unit structure as an axis of symmetry. A fifth unit structure and a sixth unit structure are respectively arranged on both sides of the second unit structure. The fifth unit structure and the sixth unit structure are structurally symmetrical about the second unit structure as an axis of symmetry.
[0014] In one embodiment, the unit structure includes a first support rod and a second support rod. One end of the first support rod and one end of the second support rod converge together and are connected to the same connection point. The other ends of the first support rod and the other ends of the second support rod are respectively connected to different positions on the first support portion. The first support rod includes a straight rod or a curved rod, and the second support rod includes a straight rod or a curved rod.
[0015] In one embodiment, the sidewall of the first support portion where the second part is located protrudes outward, or the sidewall of the first support portion where the second part is located is arranged parallel to the axial direction of the support body.
[0016] In one embodiment, the inflow end of the outer support is provided with an outwardly turned support skirt, the support skirt is connected to the first support portion, and the support skirt includes a first support skirt and a second support skirt that are circumferentially connected to each other. The first support skirt is connected to the first portion, and the second support skirt is connected to the second portion. The degree to which the first support skirt turns outward is greater than the degree to which the second support skirt turns outward.
[0017] In one embodiment, the support skirt includes a skirt connector and a skirt extension connected to each other. One end of the skirt connector is connected to the first support portion, and the other end of the skirt connector is connected to the skirt extension. The skirt connector includes an elastic structure. Attached Figure Description
[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:
[0019] Figure 1 This is a schematic diagram of the structure of a valve prosthesis provided in one embodiment.
[0020] Figure 2 This is a schematic diagram of the structure of a valve prosthesis provided in one embodiment.
[0021] Figure 3 This is a schematic diagram of the structure of the support body provided in one embodiment.
[0022] Figure 4 This is a schematic diagram of the structure of the support body provided in one embodiment.
[0023] Figure 5 This is a schematic diagram of the structure of the outer support provided in one embodiment.
[0024] Figure 6 This is a schematic diagram of the structure of the outer support provided in one embodiment.
[0025] Figure 7 This is a schematic diagram of the unit structure of the second support portion provided in one embodiment.
[0026] Figure 8 This is a schematic diagram of a partially unfolded structure of the outer support provided in one embodiment.
[0027] Figure 9 This is a schematic diagram of the force on the first support portion provided in one embodiment.
[0028] Figure 10 This is a schematic diagram of the structure of the first support portion provided in one embodiment.
[0029] Figure 11 This is a schematic diagram of the structure of the inner support and transition section provided in one embodiment.
[0030] Figure 12 This is a schematic diagram of the structure of the inner support and transition section provided in one embodiment.
[0031] Figure 13 This is a schematic diagram of the structure of a leaflet provided in one embodiment.
[0032] Figure 14 This is a schematic diagram of the structure of a leaflet provided in one embodiment.
[0033] Figure 15 This is a schematic diagram of the inner scaffold coating structure provided in one embodiment.
[0034] Figure 16 This is a schematic diagram of the inner scaffold coating structure provided in one embodiment.
[0035] Figure 17 This is a schematic diagram of a support body, transition section, connector and tension member provided in one embodiment.
[0036] Figure 18This is a schematic diagram of the structure of the second outer coating provided in one embodiment.
[0037] Figure 19 This is a schematic diagram of a support body, transition section, connector and tension member provided in one embodiment.
[0038] Figure 20 This is a schematic diagram of the structure of the first outer coating provided in one embodiment. Detailed Implementation
[0039] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
[0040] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.
[0041] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.
[0042] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented as "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.
[0043] It should be noted that the terms "distal" and "proximal" are used as directional terms, which are commonly used in the field of interventional medical devices. "Distal" refers to the end furthest from the operator during the procedure, while "proximal" refers to the end closest to the operator. Axial direction refers to the direction parallel to the line connecting the distal and proximal centers of the medical device; radial direction refers to the direction perpendicular to the aforementioned axial direction; circumferential direction refers to the direction surrounding the outer surface of the medical device.
[0044] See Figure 1 and Figure 2 This embodiment provides a valve prosthesis 100, including a stent body 1 and a leaflet 2. The stent body 1 includes an inflow end A and an outflow end B. The stent body 1 includes an inner stent 11 and an outer stent 12. The inner stent 11 is disposed inside the outer stent 12, and the leaflet 2 is disposed inside the inner stent 11.
[0045] In this embodiment, the stent body 1 is a self-expanding stent. The stent body 1 is compressed inside the delivery sheath and can self-expand after being released from the delivery sheath. In other embodiments, the stent body 1 may also be a ball-expanding stent.
[0046] See Figure 2 and Figure 3The outflow end B includes multiple connection points 13. The outer support 12 and the inner support 11 are connected to the connection points 13 after being connected at or near the outflow end B. The multiple connection points 13 form a circle 101 with a circumference. The multiple connection points 13 equally divide the circumference 101. It should be noted that when at least 80% of the connection points are on the circumference of the same circle 101, and the difference between the distance from less than 20% of the connection points not on the circumference of the circle 101 to the center of the circle 101 and the radius of the circle 101 does not exceed ±5%, it can be referred to as "multiple connection points 13 forming a circle 101". When less than 20% of the connection points are not on the circumference of the same circle 101, the intersection of the ray with the center of the circle 101 as the starting point and passing through the connection point with the circle 101, together with the other connection points on the circumference of the same circle 101, equally divides the circumference of the circle 101, which can also be referred to as "multiple connection points 13 equally dividing the circumference".
[0047] In this embodiment, by placing the inner stent 11 inside the outer stent 12 and the leaflet 2 inside the inner stent 11, the outer stent 12 can be fixed in place with the tissue, preventing paravalvular leakage. Simultaneously, it ensures that the inner stent 11 with the leaflet 2 is not compressed by the tissue, thus avoiding affecting the working state of the leaflet 2. Furthermore, the outflow end B includes multiple connection points 13. The outer stent 12 and the inner stent 11 are connected at or near the outflow end B and then connected to the connection points 13. The multiple connection points 13 form a circle 101 with a circumference. The multiple connection points 13 equally divide the circumference. This ensures that the outflow end B of the stent body 1 has a symmetrical structure, allowing the stent body 1 to be uniformly compressed into the delivery sheath, ensuring the compression and subsequent release of the stent body 1. It also ensures that the stent body 1 is evenly stressed when placed at the lesion site, thus preventing it from easily falling out.
[0048] See Figure 5 The outer stent 12 includes a first stent portion 121 and a second stent portion 122 connected axially. The plane C where the first stent portion 121 and the second stent portion 122 are connected is perpendicular to the axis O of the stent body 1. The second stent portion 122 is connected to or near the outflow end B of the inner stent 11. This configuration ensures that the first stent portion 121 always maintains a uniform stress distribution, further ensuring the compression and subsequent release of the stent body 1, and ensuring uniform stress distribution when the stent body 1 is placed at the lesion site.
[0049] The second support portion 122 is connected to the first support portion 121 at an angle. The second support portion 122 includes multiple support rods 1220, and the support rods 1220 include at least one of straight rods and curved rods.
[0050] Furthermore, combined Figure 5 and Figure 6 The second stent portion 122 includes multiple unit structures 1221 distributed circumferentially. Each unit structure 1221 includes multiple stent rods 1220. One end of each stent rod 1220 converges and connects to the same connection point 13. The other ends of at least two stent rods 1220 are respectively connected to different positions on the first stent portion 121. Since the outer stent 12 is connected to the inner stent 11 through the second stent portion 122, this arrangement of the second stent portion 122 avoids setting the second stent portion 122 in a grid pattern such as a rhombus, which would make the connection between the outer stent 12 and the inner stent 11 too rigid and unable to disperse the compressive force of the valve annulus on the outer stent 12, thus affecting the morphology of the leaflets connected to the inner stent 11 and impacting hemodynamics. Setting the stent rod 1220 as a curved rod will make the outer stent 12 more flexible, easier to deform and fit the tissue, and can increase the flexible connection between the outer stent 12 and the inner stent 11, further dispersing the compressive force of the valve annulus on the outer stent 12.
[0051] In this embodiment, the projection of the first support portion 121 onto a cross-section perpendicular to the axis is D-shaped. The D-shape includes a first segment 1210 and a second segment 1211 that are circumferentially connected. The arc length of the first segment 1210 is greater than the arc length of the second segment 1211. The portion of the first support portion 121 corresponding to the first segment 1210 is the first part 12100, and the portion of the first support portion 121 corresponding to the second segment 1211 is the second part 12110. It should be noted that the D-shape is not necessarily a perfectly standard D-shape. The D-shape can be understood as the first segment 1210 and the second segment 1211 having different curvatures, wherein the curvature of the first segment 1210 is greater than the curvature of the second segment 1211. When the valve prosthesis 100 is placed in the mitral valve, the second part 12110 of the first support part 121 is placed on the anterior leaflet of the original leaflet, and the first part 12100 of the first support part 121 is placed on the posterior leaflet of the original leaflet, so that it can fit more closely with the anatomical structure of the original leaflet, thereby avoiding paravalvular leakage.
[0052] Furthermore, the second support portion 122 includes unit structures 1221 distributed circumferentially. Each unit structure 1221 includes a first unit structure 12211 and a second unit structure 12212 with identical structures. The first unit structure 12211 is located at the middle position of the first portion 12100, and the second unit structure 12212 is located at the middle position of the second portion 12110. A third unit structure 12213 and a fourth unit structure 12214 are respectively arranged on both sides of the first unit structure 12211. The third unit structure 12213 and the fourth unit structure 12214 are symmetrically arranged with the first unit structure 12211 as the axis of symmetry. A fifth unit structure 12215 and a sixth unit structure 12216 are respectively arranged on both sides of the second unit structure 12212. The fifth unit structure 12215 and the sixth unit structure 12216 are symmetrically arranged with the second unit structure 12212 as the axis of symmetry. This configuration allows the D-shaped first stent portion 121 to have a symmetrical structure, making the force on the first stent portion 121 more uniform, further ensuring the compression and subsequent release state of the stent body 1, and ensuring that the force on the stent body 1 is uniform when placed at the lesion site.
[0053] The unit structure 1221 includes a first support rod 1222 and a second support rod 1223. One end of the first support rod 1222 and one end of the second support rod 1223 converge together and are connected to the same connection point 13. The other ends of the first support rod 1222 and the other ends of the second support rod 1223 are respectively connected to different positions on the first support part 121. The first support rod 1222 includes a straight rod or a curved rod, and the second support rod 1223 includes a straight rod or a curved rod.
[0054] In one embodiment, see Figure 7 Specifically, when at least one of the first support rod 1222 and the second support rod 1223 is a curved rod, the curved rod includes a plurality of S-shaped curved rods connected end to end. In this embodiment, after one end of the first support rod 1222 and one end of the second support rod 1223 are connected, they continue to extend towards the outlet end to form a connecting rod 1224. This connecting rod 1224 is connected to the inner support 11 to form a connection point 13. In other embodiments, after one end of the first support rod 1222 and one end of the second support rod 1223 are connected, they are directly connected to the inner support 11 to form the connection point 13.
[0055] In this embodiment, the sidewall of the first stent portion 121, where the second portion 12110 is located, protrudes outward to increase the overall rigidity of the first stent portion 121. This is particularly important in the middle of the D-shaped second portion 12110, where a lack of tight fit with the heart tissue could easily lead to paravalvular leakage. In other embodiments, the sidewall of the first stent portion 121, where the second portion 12110 is located, is arranged parallel to the axis O of the stent body 1.
[0056] See Figure 8 , Figure 8 This is a partially unfolded schematic diagram of the outer support 12. The fabrication process of the outer support 12 includes cutting a nickel-titanium tube to form a hollow tubular structure. During the cutting process, the axial length of each support rod 1220 in the same unit structure 1221 is the same. For example, the same unit structure 1221 includes a first support rod 1222 and a second support rod 1223, where the first support rod 1222 is a curved rod and the second support rod 1223 is a straight rod. After cutting, the axial length of both the first support rod 1222 and the second support rod 1223 is H. This design facilitates the cutting operation and ensures that each unit structure 1221 is axially aligned and not skewed, facilitating subsequent processing.
[0057] After the outer support 12 is cut, the hollowed-out tubular structure of the outer support 12 needs to be unfolded and shaped, combined with... Figure 4 , Figure 5 and Figure 7 To ensure the first support portion 121 of the outer support 12 remains upright and straight after unfolding, it can be unfolded radially and shaped into a D-shape using a mold. At this point, the plane C where the first support portion 121 connects to the second support portion 122 is perpendicular to the axis O of the support body. Further, to connect the outer support 12 to the inner support 11 and then to the connection points 13, multiple connection points 13 form a circle 101. The circle 101 has a circumference, and the multiple connection points 13 equally divide the circumference. In this case, the length or position of the support rods 1220 of the unit structure 1221 needs to be adjusted. Straight rods can only be adjusted in position, while curved rods can be adjusted in both length and position. Therefore, in this embodiment, the second support portion 122 in the outer support 12, through its own adjustment, can better assist and ensure the upright and symmetrical shape of the first support portion 121, allowing the first support portion 121 in the outer support 12 to better conform to the tissue and reducing the likelihood of perivalvular leakage.
[0058] See again Figure 5 and Figure 6 The inflow end A of the outer stent 12 is provided with an outwardly folded stent skirt 123, which is connected to the first stent portion 121. The stent skirt 123 includes a first stent skirt 1231 and a second stent skirt 1232 that are circumferentially connected. The first stent skirt 1231 is connected to the first portion 12100, and the second stent skirt 1232 is connected to the second portion 12110. The outward folding degree of the first stent skirt 1231 is greater than that of the second stent skirt 1232. Due to the anatomical structure of the target tissue, the above-mentioned outward folding configuration better conforms to the target tissue, reducing the gap between the outer stent 12 and the target tissue, thereby reducing thrombus formation.
[0059] In one embodiment, the support skirt 123 includes a skirt connector 1233 and a skirt extension 1234 connected to each other. One end of the skirt connector 1233 is connected to the first support portion 121, and the other end of the skirt connector 1233 is connected to the skirt extension 1234. The skirt connector 1234 includes an elastic structure, which can be a curved rod structure or other elastic structures, thereby better adapting to the tissue structure and providing greater flexibility. Specifically, the skirt extension 1234 has a V-shaped structure and is circumferentially connected.
[0060] In one embodiment, see Figure 5 and Figure 6 An anchor structure 14 is provided on the outer periphery of the first stent portion 121, and the anchor structure 14 is only provided on the first part 12100 corresponding to the first segment 1210. This arrangement ensures that the first part 12100 corresponding to the first segment 1210 on the first stent portion 121 with the anchor structure 14 is not directed towards the aortic valve, thereby preventing the anchor structure 14 from damaging the aortic valve during heartbeat and improving safety. At the same time, providing the anchor structure 14 on the first part 12100 corresponding to the first segment 1210 on the first stent portion 121 can improve the fixation performance of the valve prosthesis.
[0061] The anchor structure 14 includes multiple anchors 140, which are distributed in one or more layers on the first part 12100, with each layer of anchors 140 arranged circumferentially.
[0062] In one embodiment, an anchor 140 is provided at the end of the first portion 12100 that connects to the second portion 12110 and near the end. The anchor 140 at the end of the first portion 12100 that connects to the second portion 12110 and near the end is an end anchor 140a. The hardness of the end anchor 140a is less than the hardness of the anchors 140 at other locations on the first portion 12100; or / and, the number of end anchors 140a is less than the number of anchors 140 at other locations on the first portion 12100. In this embodiment, when the valve prosthesis 100 is placed in the mitral valve, the regions M and N at the end of the first portion 12100 that connects to the second portion 12110 and near the end are located at the anterior mitral commissure and the posterior mitral commissure, respectively. Figure 9When the valve prosthesis 100 is inserted into the delivery sheath 200, it will be gradually squeezed by the delivery sheath 200. Since the cross-section of the delivery sheath 200 is circular and the first support portion 121 of the outer support 12 of the valve prosthesis 100 is D-shaped, the force on the outer periphery of the first support portion 121 of the outer support 12 is uneven. Among them, the regions M and N on the first support portion 121 of the outer support 12 are the first to come into contact with the delivery sheath 200. As the delivery sheath 200 gradually compresses radially, these two parts are subjected to greater pressure than other parts. When the limit of the overall structure is reached, the outer support 12 will become unstable, and the first support portion 121 of the outer support 12 will fold inward. After the first support portion 121 of the outer support 12 folds inward, it will squeeze the leaflet 2 inward, which will cause damage to the surface of the leaflet 2. Calcification may occur later, and the leaflet 2 is prone to perforation and rupture, reducing the service life of the artificial valve. Therefore, by reducing the number of anchors or lowering the hardness of the anchors in regions M and N, this embodiment can effectively alleviate the uneven force distribution on the first support portion 121 of the outer support 12 caused by the interaction between the first support portion 121 of the D-shaped outer support 12 and the circular cross-section delivery sheath 200.
[0063] In another embodiment, see Figure 10 Multiple anchors 140 are circumferentially distributed on the first support portion 121. In the projection of the first support portion 121 onto a cross section perpendicular to the axis, the radially outermost ends of all anchors 140 are located on the outer periphery of the same circle P. This arrangement is also to effectively alleviate the uneven force on the first support portion 121 of the D-shaped outer support 12 caused by the interaction between the first support portion 121 and the circularly shaped delivery sheath 200. When the valve prosthesis 100 is retracted into the delivery sheath 200, the radial compression of the first support portion 121 of the outer support 12 is more uniform, thereby preventing the first support portion 121 of the outer support 12 from folding inward.
[0064] In one embodiment, see again Figure 5 The first support portion 121 includes multiple grid structures 1212, with a node 1213 between two adjacent grid structures 1212. One end of the anchor 140 / 140a is set on the node 1213, and the other end of the anchor 140 / 140a is a free end, which extends toward the inflow end and opens outward.
[0065] In one embodiment, the anchor structure 14 is disposed at the end of the first support portion 121 away from the support skirt 123. It is understood that the support skirt 123 is used to adhere to the target tissue, and the placement of the anchor structure 14 at the end away from the support skirt 123 can prevent the anchor structure 14 from affecting the adhesion between the support skirt 123 and the target tissue, thereby avoiding perivalvular leakage.
[0066] See again Figure 1 and Figure 2 The valve prosthesis 100 also includes a cover 3, which includes an outer stent cover 31 and an inner stent cover 32. The outer stent cover 31 is disposed on the outer stent 12, and the inner stent cover 32 is disposed on the inner stent 11. The outer stent cover 31 and the inner stent cover 32 are fixed at or near the outflow end B to form a seal between the outer stent cover 31 and the inner stent cover 32, thereby preventing paravalvular leakage.
[0067] In this embodiment, see Figures 11 to 16 The valve prosthesis 100 includes a plurality of circumferentially connected leaflets 2. Adjacent leaflets 2 have circumferentially spaced openings Q near the inflow end A. The inner stent cover 32 includes a plurality of circumferentially connected inner stent cover units 320. Adjacent inner stent cover units 320 have circumferentially spaced openings W near the inflow end A. One end of a leaflet 2 near the inflow end A and one inner stent cover unit 320 are both fixed to the inner stent 11, such that the end of the inner stent cover unit 320 near the inflow end A coincides with the end of the leaflet 2 near the inflow end A, or the end of the inner stent cover unit 320 near the inflow end A extends further into the inflow end A than the end of the leaflet 2 near the inflow end A, such that the area of W is less than or equal to the area of Q. It should be noted that the end of the leaflet 2 near the inflow end A here refers to the boundary of the end of the leaflet 2 near the inflow end A (e.g., Figure 13 The arc-shaped boundary 23 of the leaflet 2 in the middle does not refer to an endpoint; the end of the inner stent covering unit 320 near the inflow end A also refers to the boundary of the end of the inner stent covering unit 320 near the inflow end A (e.g. Figure 15 The arc-shaped boundary 321 of the inner stent covering unit 320 does not refer to an endpoint. This configuration can remove unnecessary covering at the inflow end A of the inner stent 11, minimizing the covering area at the inflow end of the inner stent 11. This increases the blood flow space at the inflow end of the inner stent 11, increasing the blood flow volume and rate, preventing blood stasis, and avoiding thrombosis. At the same time, the boundary of the leaflet 2 near the inflow end A can be set within the boundary of the inner stent covering unit 320 near the inflow end A, preventing blood leakage and thus paravalvular leakage.
[0068] In one embodiment, the circumferentially spaced openings W are all inverted triangle-shaped openings, with the length of the end near the inflow end being longer than the length of the end near the outflow end. The inverted triangle-shaped opening can be understood as a standard inverted triangle, or a simple variation of a standard inverted triangle (e.g., the three sides of an inverted triangle are curves, broken lines, etc.). The circumferentially spaced openings Q can also be inverted triangle-shaped openings.
[0069] In this embodiment, see Figure 13 and 15 The leaflet 2 has a first suture hole 21 near the inflow end A, and the inner support membrane unit 320 has a second suture hole 3201 near the inflow end A. The leaflet 2, the inner support membrane unit 320, and the inner support 11 are fixed together with sutures through the first suture hole 21 and the second suture hole 3201. In other embodiments, the leaflet 2, the inner support membrane unit 320, and the inner support 11 can also be fixed together by adhesive.
[0070] In this embodiment, on the inner support film 32, a window 3202 is provided between adjacent inner support film units 320 for the leaflet corner 22 to pass through and be fixed to the inner support film unit 320 and the inner support 11.
[0071] See Figures 17 to 20 In one embodiment, the outer support membrane 31 includes a first outer membrane 311 and a second outer membrane 312. The first outer membrane 311 is at least partially disposed outside the outer support 12, and the second outer membrane 312 is at least partially disposed inside the outer support 12. The second outer membrane 311 and the inner support membrane 32 are fixed at or near the outlet end B to form a seal between the second outer membrane 311 and the inner support membrane 32.
[0072] The first outer covering 311 and / or the second outer covering 312 wraps around the inflow end A of the outer stent 12, preventing the inflow end A of the outer stent 12 from being exposed and thus puncturing tissue. In one embodiment, after the second outer covering 312 covers the inner surface of the outer stent 12 and reaches the inflow end A of the outer stent 12, it continues to extend outward, so that there is a gap between the inflow end A of the outer stent 12 and the end of the second outer covering 312 near the inflow end, so as to provide space for the outer stent 12 to be compressed or expanded, thereby avoiding puncture of the outer stent covering 31.
[0073] In one embodiment, see Figure 17 , 18In embodiments 19 and 10, the second outer layer coating 312 has a body portion 3121 and an outwardly folded portion 3122, wherein the body portion 3121 is located inside the outer layer support 12, and the outwardly folded portion 3122 folds outward around the inflow end A of the outer layer support 12 to the outside of the outer layer support 12, and the first outer layer coating 311 at least partially covers the outwardly folded portion 3122. Similarly, in other embodiments, the first outer layer coating 311 may be provided with an inwardly folded portion (not shown), which folds inward around the inflow end A of the outer layer support 12 to the inside of the outer layer support 12, and the second outer layer coating 312 at least partially covers the inwardly folded portion.
[0074] In one embodiment, the end of the first outer film 311 near the inflow end overlaps and is fixed with the end of the second outer film 312 near the inflow end. This embodiment can be understood as the first outer film 311 or the second outer film 312 not having an outward or inward folding portion.
[0075] In this embodiment, the first outer membrane 311 has a loose and porous structure with good extensibility, which is suitable for cell growth and achieves rapid endothelialization; the second outer membrane 312 includes a blood sealing material, which isolates blood and prevents leakage.
[0076] In one embodiment, the first outer covering 311 at least covers the skirt 123 of the outer support 12. The first outer covering 311 is separate from the anchor structure 14 and does not overlap, thereby reducing the outer diameter of the valve prosthesis 100 after radial compression, which facilitates the insertion of a smaller sheath.
[0077] In this embodiment, see Figure 11 and Figure 12 The inner support 11 has a mesh structure, which includes multiple rhomboid meshes 110. The rhomboid meshes 110 are connected circumferentially to form a mesh layer. The multiple rhomboid meshes 110 include multiple mesh layers. This structure has good support and can better support the leaflet 2, so that the leaflet is not easily deformed during operation, avoiding perivalvular leakage and affecting blood flow rate.
[0078] See again Figure 1 and Figure 12In this embodiment, the valve prosthesis 100 further includes a transition segment 5, a connector 6, and a traction member 7. One end of the transition segment 5 is connected to the stent body 1, and the other end is connected to the connector 6, which in turn is connected to the traction member 7. Initially, after implantation, the valve prosthesis 100 is primarily fixed to the apical tissue via the traction member 7. After a period of time, as mitral regurgitation disappears and left ventricular remodeling and deformation decrease, the traction member 7 will loosen. At this point, the valve prosthesis 100 has achieved good endothelialization, and its fixation is mainly achieved through the anchor structure 140. The anchor structure 140 ensures that the valve prosthesis 100 does not shift, providing a good foundation for complete endothelialization of the artificial valve. Subsequently, the valve prosthesis 100 is fully endothelialized and is unlikely to detach.
[0079] In this embodiment, one end of the transition section 5 is connected to the inner stent 11 of the stent body 1 to prevent the force of the traction member 7 from affecting the outer stent 12, causing deformation of the outer stent 12, thereby affecting the overall fixation and sealing performance of the valve prosthesis 100. The transition section 5 includes multiple circumferentially distributed connecting units 51, with a channel 52 between adjacent connecting units 51, providing operating space for secondary surgeries. The connecting units 51 themselves may also have space, providing operating space for secondary surgeries.
[0080] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A valve prosthesis, comprising a stent body and valve leaflets, the stent body including an outflow end and an inflow end, characterized in that, The main body of the support includes an inner support and an outer support. The inner support is disposed inside the outer support, and the leaflets are disposed inside the inner support. The outflow end includes multiple connection points. The outer support and the inner support are connected at or near the outflow end and then connected to the connection points. The multiple connection points form a circle with a circumference, and the multiple connection points equally divide the circumference.
2. The valve prosthesis as described in claim 1, characterized in that, The outer support includes a first support portion and a second support portion connected axially. The plane at the end where the first support portion and the second support portion are connected is perpendicular to the axis of the support body. The second support portion is connected to the outlet end of the inner support or near the outlet end.
3. The valve prosthesis as described in claim 1, characterized in that, The second support portion is connected to the first support portion at an angle, and the second support portion includes multiple support rods, the support rods including at least one of straight rods and curved rods.
4. The valve prosthesis as described in claim 3, characterized in that, The second support portion includes multiple unit structures distributed circumferentially. Each unit structure includes multiple support rods. One end of each support rod converges and connects to the same connection point. The other ends of at least two of the support rods are respectively connected to different positions on the first support portion.
5. The valve prosthesis as described in claim 1, characterized in that, The outer support includes a first support portion and a second support portion connected axially. The second support portion is connected to or near the outlet end of the inner support. The projection of the first support portion on a cross section perpendicular to the axis is D-shaped. The D-shape includes a first segment and a second segment connected circumferentially. The arc length of the first segment is greater than the arc length of the second segment. The portion of the first support portion corresponding to the first segment is the first part, and the portion of the first support portion corresponding to the second segment is the second part.
6. The valve prosthesis as described in claim 5, characterized in that, The second support portion includes multiple unit structures distributed circumferentially. The unit structures include a first unit structure and a second unit structure with identical structures. The first unit structure is located at the middle position of the first portion, and the second unit structure is located at the middle position of the second portion. A third unit structure and a fourth unit structure are respectively arranged on both sides of the first unit structure. The third unit structure and the fourth unit structure are structurally symmetrical about the first unit structure as the axis of symmetry. A fifth unit structure and a sixth unit structure are respectively arranged on both sides of the second unit structure. The fifth unit structure and the sixth unit structure are structurally symmetrical about the second unit structure as the axis of symmetry.
7. The valve prosthesis as described in claim 6, characterized in that, The unit structure includes a first support rod and a second support rod. One end of the first support rod and one end of the second support rod converge together and are connected to the same connection point. The other ends of the first support rod and the other ends of the second support rod are respectively connected to different positions on the first support part. The first support rod includes a straight rod or a curved rod, and the second support rod includes a straight rod or a curved rod.
8. The valve prosthesis as described in claim 5, characterized in that, The side wall of the first support portion where the second part is located protrudes outward, or the side wall of the first support portion where the second part is located is arranged parallel to the axial direction of the support body.
9. The valve prosthesis as described in claim 5, characterized in that, The inflow end of the outer support is provided with an outwardly turned support skirt. The support skirt is connected to the first support part. The support skirt includes a first support skirt and a second support skirt that are circumferentially connected to each other. The first support skirt is connected to the first part, and the second support skirt is connected to the second part. The degree to which the first support skirt turns outward is greater than the degree to which the second support skirt turns outward.
10. The valve prosthesis as described in claim 9, characterized in that, The support skirt includes a skirt connector and a skirt extension that are connected to each other. One end of the skirt connector is connected to the first support portion, and the other end of the skirt connector is connected to the skirt extension. The skirt connector includes an elastic structure.