Prosthetic heart valve

Abstract

The utility model relates to a kind of artificial heart valve, including valve frame, first film, second film and at least two pieces of relatively open and close artificial valve leaflet. First film is fixedly connected to valve frame on the radial inner side of valve frame;Artificial valve leaflet is fixedly connected to first film and / or valve frame. Second film is in flat state before being installed to valve frame, the length of second film in flat state is greater than the circumference of valve frame. Second film has annular capsule after being installed to valve frame, which can be outwardly convex on the radial outer side of valve frame, a plurality of recesses are arranged on second film, to form inlet for fluid into annular capsule. The effective height of annular capsule is reduced compared to the height of second film in flat state, and the effective depth of recess on annular capsule is reduced compared to the depth of recess in flat state. The artificial heart valve can effectively reduce or even eliminate paravalvular leakage.

Description

Technical Field

[0001] This utility model relates to the field of medical devices, specifically to an artificial heart valve. Background Technology

[0002] Aortic valve disease is a common heart condition, including aortic stenosis and aortic regurgitation. In recent years, transcatheter aortic valve replacement has become an effective treatment for severe aortic stenosis.

[0003] Transcatheter aortic valve replacement (TAVR) establishes a minimally invasive interventional pathway through peripheral blood vessels, delivering a compressed artificial heart valve mounted on a delivery device to the diseased native aortic valve. The delivery device is then manipulated to expand the artificial heart valve, thereby replacing the diseased native aortic valve with the artificial heart valve.

[0004] Clinical research data indicate that a key challenge in transcatheter aortic valve replacement (TAVR) lies in how to effectively control perivalvular regurgitation, i.e., perivalvular leakage. Summary of the Invention

[0005] In view of this, the present invention aims to provide an artificial heart valve that can effectively reduce paravalvular leakage.

[0006] The artificial heart valve includes a valve frame, a first membrane, a second membrane, and at least two opposing, openable artificial leaflets. The first membrane is fixedly connected to the valve frame radially inward; the artificial leaflets are fixedly connected to the first membrane and / or the valve frame; the second membrane is in a flat state before being installed onto the valve frame, and the length of the second membrane in the flat state is greater than the circumference of the valve frame; after being installed onto the valve frame, the second membrane has an annular sac that can bulge outward radially outward from the valve frame; the second membrane has a plurality of spaced-apart notches to form inlets for fluid to enter the annular sac. The effective height of the annular sac is reduced compared to the height of the second membrane in the flat state; the effective depth of the notches on the annular sac is reduced compared to the depth of the notches in the flat state.

[0007] The artificial heart valve provided by this invention features a second membrane whose length in its flat state is greater than the circumference of the valve frame, and multiple spaced notches on the second membrane. After the second membrane is installed on the valve frame, it has an annular sac that bulges outward radially from the valve frame. The effective height of the annular sac is reduced compared to the height of the second membrane in its flat state, and the effective depth of the notches on the annular sac is reduced compared to the depth of the notches in its flat state. Fluid can enter through the notches and inflate the annular sac, allowing the annular sac to adaptively conform to the native valve annulus, sealing the various gaps between the artificial heart valve and the native valve annulus, thereby effectively reducing or even eliminating paravalvular leakage. Attached Figure Description

[0008] Figure 1A This is a three-dimensional structural diagram of an artificial heart valve according to an embodiment of the present invention, viewed from one angle.

[0009] Figure 1B This is a three-dimensional structural diagram of an artificial heart valve according to an embodiment of the present invention from another perspective;

[0010] Figure 1C This is a front view schematic diagram of an artificial heart valve according to an embodiment of the present invention;

[0011] Figure 1D This is a top view schematic diagram of an artificial heart valve according to an embodiment of the present invention;

[0012] Figure 1E This is a three-dimensional exploded view of an artificial heart valve according to an embodiment of the present invention;

[0013] Figure 2A yes Figures 1A-1E A schematic diagram of the assembly of the first and second membranes in an artificial heart valve is shown.

[0014] Figure 2B yes Figures 1A-1E The diagram shows the assembly of the first membrane and the artificial leaflet in an artificial heart valve.

[0015] Figure 3 This is a schematic diagram of the second membrane in its flat state;

[0016] Figure 4A yes Figure 1C A magnified view of a portion of point 1-1 in the diagram;

[0017] Figure 4B yes Figure 1C Enlarged view of the area at points 1-2 in the middle;

[0018] Figure 5AThis is a schematic diagram of the artificial heart valve implanted into the native aortic valve according to this utility model;

[0019] Figure 5B yes Figure 5A A schematic diagram of the state in which the annular sac of an artificial heart valve is filled with blood.

[0020] Figure 5C yes Figure 5A A schematic diagram of an artificial heart valve in the Y-direction view;

[0021] Figure 6A This is a schematic diagram of a second membrane in a flat state, representing another structural form.

[0022] Figure 6B This is a schematic diagram of a second membrane in a flat state, representing another structural form.

[0023] Figure 6C This is a schematic diagram of a second membrane in a flat state, representing yet another structural form.

[0024] Figure 7A This is a schematic diagram of an artificial heart valve according to another embodiment of the present invention from a top view.

[0025] Figure 7B This is a schematic diagram of an artificial heart valve according to another embodiment of the present invention, viewed from a top-down perspective. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Furthermore, the embodiments described below can be combined with each other as long as there is no contradiction or conflict, and the same or similar concepts or processes may not be repeated in some embodiments.

[0027] First, it should be noted that in this article, "proximal" refers to the end of the device or element closer to the operator, and "distal" refers to the end of the device or element farther from the operator. Following the direction of blood flow in the heart, "inflow end" refers to the end upstream of the blood flow, and "outflow end" refers to the end downstream of the blood flow. "Axial" refers to the direction that coincides with or is parallel to the central axis of the device or element. "Radial" refers to the direction perpendicular to or approximately perpendicular to the axial direction and along the radius or diameter of the device or element. "Circumferential" refers to the direction surrounding the axial direction.

[0028] It is worth noting that the terms such as the indicated orientation or positional relationship are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model.

[0029] It is also worth noting that the artificial heart valve and its components in this invention have a compression structure suitable for delivery, as well as an expansion structure in the free state or after deployment. Unless otherwise specified, the structural description below is made under the expansion structure.

[0030] Please see Figures 1A to 1E This invention provides an artificial heart valve 100 suitable for replacing a diseased native aortic valve. The artificial heart valve 100 includes a valve frame 10, a first membrane 30, a second membrane 40, and at least two artificial leaflets 50. The first membrane 30 is fixedly connected to the valve frame 10 radially inward, and the artificial leaflets 50 are fixedly connected to the first membrane 30 and / or the valve frame 10. One end 401 of the second membrane 40 is folded to the radially inward side of the valve frame 40 and fixedly connected to the first membrane 30, while a portion of the other end 403 of the second membrane 40 is fixedly connected to the valve frame 10 and / or the first membrane 30 radially outward. The fixed connection is preferably, but not limited to, a suture connection. When the artificial leaflets 50 are open relative to each other, the artificial heart valve 100 allows antegrade blood flow (such as from the left ventricle to the aorta) to pass through. When the artificial leaflets 50 are closed relative to each other, retrograde blood flow (such as from the aorta to the left ventricle) is inhibited.

[0031] like Figure 1C and Figure 1EAs shown, the petal frame 10 is generally cylindrical and includes multiple rows of grids. Each row of grids includes multiple interconnected cells that are enclosed in a ring around the perimeter. For example, the multiple rows of grids include inflow and outflow grids axially opposite to each other at both ends of the petal frame 10 (the distal end being the inflow end and the proximal end being the outflow end), and at least one, two, or three intermediate rows of grids axially located between the inflow and outflow grids. The inflow grid includes multiple inflow cells G1, the outflow grid includes multiple outflow cells G3, and the intermediate rows include multiple intermediate cells G2. The inflow cells G1 may be, but are not limited to, hexagonal grids enclosed by six support rods 13; the intermediate cells G2 may be, but are not limited to, quadrilateral grids enclosed by four support rods, such as rhombuses; and the outflow cells G3 may be, but are not limited to, quadrilateral grids enclosed by four support rods, such as rhombuses. The valve frame 10 can switch between a compression configuration and an expansion configuration. Specifically, the valve frame 10 can be fabricated from any suitable plastic expandable material (e.g., stainless steel, cobalt-chromium alloy) or self-expanding material (e.g., nickel-titanium alloy) using a laser cutting process. When the valve frame 10 is made of a plastic expandable material, the valve frame 10 and the entire artificial heart valve 100 can be compressed into a compression configuration using a gripping tool; after the artificial heart valve 100 is delivered to a predetermined position, it is expanded by an inflatable balloon, causing the valve frame 10 to switch to an expansion configuration. When the valve frame 10 is made of a self-expanding material, the valve frame 10 and the entire artificial heart valve 100 can be compressed into a compression configuration using a gripping tool or a loading tool; after the artificial heart valve 100 is delivered to a predetermined position, the valve frame 10 and the entire artificial heart valve 100 automatically expand to their expansion configuration. Compared to the compressed artificial heart valve 100, the expanded artificial heart valve 100 has a shorter axial dimension but a larger radial and circumferential dimension because each cell expands to a preset shape and size.

[0032] like Figures 1A to 1E ,and Figure 2B As shown, the number of artificial leaflets 50 is preferably, but not limited to, three. The artificial leaflets 50 can be formed from animal pericardial tissue (such as bovine pericardium or porcine pericardium) or suitable biocompatible synthetic materials. Each artificial leaflet 50 includes a leaflet body 51 and lugs 53 extending from both sides of the leaflet body 51. The leaflet body 51 has an mating edge 511 (or free edge) and a fan-shaped fixed edge 513. The lugs 53 of adjacent artificial leaflets 50 can be connected together to form a lug joint 55, which can be sutured or bound to the support of the corresponding flow cell G3.

[0033] The fixed edge 513 of the artificial leaflet 50 is sutured to the first membrane 30. The two side edges 33 and 35 of the first membrane 30 are sutured together to form a cylindrical shape. The combination of the artificial leaflet 50 and the first membrane 30 is then sutured to the valve frame 10. Specifically, the fixed edge 513 of the artificial leaflet 50 and the first membrane 30 are sutured together using a flat stitch, and the left and right side edges 33 and 35 of the first membrane 30 are also sutured together using a flat stitch. The first membrane 30 can be sutured to the support rods of the inflow grid and the middle grid using a loop stitch, so that the cylindrical first membrane 30 is attached to the radial inner surface of the valve frame 10. The material of the first membrane 30 can be any of the following: polytetrafluoroethylene (PTFE), polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), etc. The inflow end of the first membrane 30 can be axially aligned with the inflow end of the valve frame 10, and the outflow end of the first membrane 30 can be axially aligned with or lower than the outflow end of the valve frame 10, ensuring that after the artificial heart valve 100 is implanted, the outflow end of the first membrane 30 is higher than the original valve annulus and can provide sufficient connection height for the fixing edge 513 of the artificial valve leaflet 50. The first membrane 30 and the artificial valve leaflet 50 cooperate to ensure that blood flows unidirectionally in the correct direction within the artificial heart valve 100, preventing leakage within the valve.

[0034] The material of the second membrane 40 can be selected from any of the following fabrics: PTFE, PP, PE, PET, etc. For example... Figure 3 As shown, the second membrane 40 is in a flat state before being installed onto the valve holder 10. In this state, the second membrane 40 is approximately a long, narrow rectangle that can be laid flat on a plane, with a length of L and a height of H. The length L can be 4 to 10 times the height H, that is, the length L can be much greater than the height H; and this length L is greater than the perimeter of the valve holder 10. The second membrane 40 has multiple spaced-apart notches 41, each notch 41 extending downwards from the other end 403 of the second membrane 40 along the height direction to form a certain depth S1. Simultaneously, each notch 41 also occupies a certain space along the length direction of the second membrane 40, thus having a width W1. A connecting portion 43 is formed between adjacent notches 41 by a portion of the second membrane 40. Figure 1B and Figure 2A One end 401 of the second membrane 40 is folded to the radially inner side of the valve frame 10 and fixedly connected to the first membrane 30. The other end 403 of the second membrane 40 is connected to the valve frame 10 and / or the first membrane 30 radially outer side of the valve frame 10 via the connecting portion 43, and the other end 403 is axially higher than the first end 401, while being lower than the outflow end of the first membrane 30. Figure 3 and Figures 1A to 1DThe length L of the second membrane 40 in its flat state is greater than the circumference of the valve frame 10. After the second membrane 40 is installed onto the valve frame 10, it forms an annular sac 45 that can bulge outward radially outward from the valve frame 10. The effective height H2 of the annular sac 45 (effective height is defined as the height exposed radially outward from the valve frame in the axial direction) is reduced compared to the height H of the second membrane 40 in its flat state, to help the annular sac 45 achieve sufficient outward bulging. Each notch 41 can connect the interior and exterior of the annular sac 40. When the artificial heart valve 100 is implanted into a diseased native valve, such as a native aortic valve, ... Figure 5A and Figure 5B As shown, blood can flow into the interior of the annular sac 40 through the notch 41, thereby inflating the annular sac 45 and causing it to bulge outwards sufficiently from the radially outer side of the valve frame 10. As previously mentioned, since one end 401 of the second membrane 40 is folded to the radially inner side of the valve frame 10 and fixedly connected to the first membrane 30, the sealing performance of the annular sac 45 is improved, increasing the difficulty of blood filling the annular sac 45 leaking from the fixed connection between the second membrane 40 and the first membrane 30.

[0035] It is worth noting that, since the length L of the second membrane 40 in its flat state is greater than the circumference of the valve frame 10, when one end 401 of the second membrane 40 is folded to the radially inner side of the valve frame 10 and fixedly connected to the first membrane 30, the one end 401 is not flat against the first membrane 30, but is sutured and fixed to the first membrane 30 at least in a local area by pleating or wrinkling. Correspondingly, at least a local portion of the annular capsule 45 has folds 451. During the outward bulging of the annular capsule 45 under the influence of blood, the folds 451 on it can be partially or completely opened.

[0036] Specifically, such as Figure 3 As shown, in this embodiment, the notch 41 is generally U-shaped. In other embodiments, the notch 41 may also be generally U-shaped. Figure 6A The "V" shape shown, such as Figure 6B The rectangle shown, such as Figure 6C The shapes shown are trapezoids or semicircles, etc.

[0037] like Figure 1C , Figure 1E , Figure 3 ,and Figure 4A and Figure 4BAs shown, in this embodiment, the height H of the second membrane 40 in its flat state is greater than the height H3 of the inflow row cell G1 (i.e., the axial distance between the inflow end node P3 and the outflow end node P1 of the inflow row cell G1). The connecting part 43 is connected to the support rod 13 located on both sides of the outflow end node P1 of the corresponding inflow row cell G1, and the notch 41 exposes the common node P2 of the adjacent outflow end node P1 of the corresponding two adjacent inflow row cells G1; the annular capsule 45 surrounds the inflow row grid circumferentially. The number of notches 41 is equal to the number of inflow row cells G1 in this embodiment. For example, if the number of inflow row cells G1 is 12, then the number of notches 41 is also 12. One notch 41 is formed by the connection of half "U" shaped notches located on both sides of the second membrane 40, and the remaining 11 notches 41 are all complete. Each notch 41 is opened between two adjacent connecting parts 43. When the valve frame 10 is in a compressed configuration, the height of the inflow row cell G1 increases, and the annular capsule 45 is forced to elongate axially, thereby reducing the degree of outward bulging. When the valve frame 10 is in an expanded configuration, the height of the inflow row cell G1 decreases, and the annular capsule 45 relaxes axially, thereby increasing the degree of outward bulging. In other words, during the transition from a compressed to an expanded configuration of the valve frame 10, the effective height of the annular capsule 45 gradually decreases, while the degree of outward bulging of the annular capsule 45 relative to the valve frame 10 gradually increases.

[0038] More specifically, each connecting part 43 is rolled inward on both sides of the corresponding outflow end node P1 to wrap the corresponding support rod 13, and is fixed by suture stitching or wrapping. The number of suture wraps is determined by the need to securely fix the connecting part 43, such as 3-5 wraps. Furthermore, in order to avoid frequent knotting of the suture, in addition to the part of the support rod 13 wrapped by the connecting part 43, the suture wrap can continue to be wrapped on the part of the support rod 13 not wrapped by the connecting part 43, thereby forming a continuous loop of suture in the circumferential direction. Only the beginning and end of the suture containing this loop need to be knotted, which helps to reduce the overall compression size of the artificial heart valve 100 and improves the operation efficiency. Understandably, because the inward rolling of the connecting portion 43 and wrapping around the corresponding support rod 13 will occupy or lose a small portion of the other end 403 of the notch 41 near the second membrane 40, the effective depth S2 of the notch 41 on the annular capsule 45 (the effective depth is defined as the maximum axial dimension of the portion of the notch 41 that can expose the valve frame) will be smaller than the depth S1 of the notch 41 in its flat state. After the connecting portion 43 is fixed, the width W2 of the notch 41 may decrease or increase as the two connecting portions 43 adjacent to the notch 41 squeeze or pull on it.

[0039] In this embodiment, when the second membrane 40 is in a flat state, the depth S1 of each notch 41 occupies 15%-30% of the height H of the second membrane 40; adjacent notches 41 and connecting portions 43 can form a repeatable unit 42, and the width W1 of the notch 41 occupies 25%-50% of the overall width W of the unit 42; the above arrangement ensures that the notches 41 have sufficient mounting foundation. After the second membrane 40 is installed onto the valve holder 10, the width W2 of the notch 41 is further set to approximately occupy 1 / 4 to 2 / 3 of the width W3 of the inflow row cell, and / or the portion of the connecting part 43 connected to the support rod 13 occupies 1 / 4 to 1 / 2 of the length L3 of the support rod 13, and the axial distance S3 of the bottom end of the notch 41 below the common node P2 is 0.5mm to 3mm, so as to ensure that the notch 41, as the inlet for blood to enter the annular sac 45, has a suitable size to meet the need for the annular sac 45 to be fully inflated by blood in a short time, and that the connection strength between the connecting part 43 and the support rod 13 is sufficient.

[0040] In this embodiment, a plurality of notches 41 are provided, equal to the number of inflow row cells G1, such as 12, and the plurality of notches 41 are evenly distributed circumferentially relative to the petal frame 10. In other embodiments, the number of notches 41 may be less than the number of inflow row cells G1, such as Figure 7A As shown, with the same condition that the number of inflow row cells G1 is 12, a notch 41 is set for every other inflow row cell G1, resulting in a total of 6 notches 41. Or, as... Figure 7B As shown, when the number of inflow row cells G1 is 12, a notch 41 is provided every two inflow row cells G1, so the number of notches 41 is 4. In some other embodiments, the connecting part 43 can be fixedly connected to the first membrane 30, then the number of notches 41 can be set to be more than the number of inflow row cells G1.

[0041] like Figures 5A to 5CAs shown, the artificial heart valve 100 of this invention is suitable for implantation and replacement of diseased native aortic valve AV. When the artificial valve leaflets close and align with each other, the blood flow at the root of the aortic valve AV is backflowed and inflates the annular sac 45 through the multiple notches 41, causing the annular sac 45 to bulge outward radially from the valve frame 10 to contact the annulus R of the native aortic valve AV. If it encounters a cavity 91 on the native annulus R, the annular sac 45 and the blood inside can adaptively deform to fill the cavity 91. If it encounters a calcified protrusion 93 on the native annulus R, the annular sac 45 and the blood inside can adaptively deform to cover the calcified protrusion 93. Thus, the annular sac 45 can adaptively seal the gaps of various shapes between the annular sac 45 and the annulus R, effectively reducing or even eliminating paravalvular leakage. Furthermore, since the fabric material of the second membrane 40 is rougher than the metal material of the valve frame 10, the annular capsule 45 can generate a certain amount of friction when it contacts the valve annulus R of the original aortic valve AV, which helps to reliably position the artificial heart valve 100. The annular capsule 45 can also provide a buffer between the artificial heart valve 100 and the valve annulus R, reducing the impact that the artificial heart valve 100 may cause to the valve annulus R during operation. In addition, thanks to the annular capsule 45, which can effectively reduce or even eliminate paravalvular leakage, the abnormal impact and stimulation of blood on the valve annulus R and other perivalvular tissues are reduced, the probability of local inflammatory response is reduced, and the damage of inflammation to the perivalvular tissues is mitigated.

[0042] The above description is only a preferred embodiment of the present utility model. The protection scope of the present utility model is not limited to the embodiments listed above. Any simple changes or equivalent substitutions of the technical solutions that can be obviously obtained by those skilled in the art within the technical scope disclosed in the present utility model shall fall within the protection scope of the present utility model.

Claims

1. An artificial heart valve, characterized in that, It includes a valve frame, a first membrane, a second membrane, and at least two artificial leaflets that can open and close relative to each other; The first membrane is fixedly connected to the valve frame on the radially inner side; the artificial valve leaflet is fixedly connected to the first membrane and / or the valve frame; The second membrane is in a flat state before being installed onto the valve frame, and the length of the second membrane in the flat state is greater than the circumference of the valve frame; after being installed onto the valve frame, the second membrane has an annular sac that can bulge outward from the radially outer side of the valve frame; the second membrane is provided with a plurality of spaced notches to form an inlet for fluid to enter the annular sac; The effective height of the annular capsule is reduced compared to the height of the second membrane in the flat state; the effective depth of the notch on the annular capsule is reduced compared to the depth of the notch in the flat state.

2. The artificial heart valve as described in claim 1, characterized in that, At least some parts of the annular cyst have folds.

3. The artificial heart valve as described in claim 1, characterized in that, One end of the second membrane is folded to the radially inner side of the valve frame and fixedly connected to the first membrane. The connecting portion of the other end of the second membrane located between adjacent notches is connected to the valve frame and / or the first membrane on the radially outer side of the valve frame, and the other end is axially higher than the first end to form the annular capsule.

4. The artificial heart valve as described in claim 3, characterized in that, The petal frame includes multiple interconnected inflow row cells, the connecting part is connected to the support rods located on both sides of the outflow end node of the inflow row cell, and the notch exposes the common node of the adjacent outflow end node of two adjacent inflow row cells.

5. The artificial heart valve as described in claim 4, characterized in that, The bottom end of the notch is axially located 0.5mm-3mm below the common node; and / or the width of the notch occupies approximately 1 / 4-2 / 3 of the width of the inflow row cell; and / or the portion of the connecting part that is connected to the support rod occupies 1 / 4-1 / 2 of the length of the support rod.

6. The artificial heart valve as described in claim 4, characterized in that, The number of notches is less than or equal to the number of cells in the inflow row.

7. The artificial heart valve as described in claim 4, characterized in that, The height of the second membrane in the flat state is greater than the height of the inflow row cell.

8. The artificial heart valve as described in claim 4, characterized in that, In the flat state, the depth of the notch occupies 15%-30% of the height of the second membrane; and / or the width of the notch occupies 25%-50% of the overall width of the unit formed by the adjacent notches and the connecting portion.

9. The artificial heart valve according to any one of claims 1-8, characterized in that, The notch is in the shape of a "U", "V", rectangle, trapezoid, or semicircle.

10. The artificial heart valve according to any one of claims 1-8, characterized in that, The valve frame can be converted from a compression structure to an expansion structure; during the conversion process, the effective height of the annular capsule gradually decreases, and the degree of outward bulging of the annular capsule relative to the valve frame can gradually increase.

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