Prosthetic heart valve and transcatheter heart valve replacement system

Abstract

The present application relates to a kind of artificial heart valve and transcatheter heart valve replacement system, the artificial heart valve described above includes valve support and outer skirt, valve support has inflow end and outflow end, valve support is successively provided with multiple circumferentially arranged grid groups from outflow end to inflow end, wherein the grid group closest to inflow end is adapted to match below annulus plane position, and the mesh size of at least one group of non-end grid group matching annulus plane is greater than the mesh size of at least one grid group adjacent to it in axial direction;Outer skirt is covered on the outer surface of valve support, outer skirt covers at least adjacent two groups of grid groups close to inflow end, and outer skirt is configured as the structure of increasing thickness in the direction from outflow end to inflow end at the position close to inflow end.

Description

Technical Field

[0001] This invention relates to the field of medical devices for cardiac surgery, and more particularly to an artificial heart valve and a transcatheter heart valve replacement system. Background Technology

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

[0003] In transcatheter aortic valve replacement surgery, it is crucial to implant the artificial aortic valve into the pre-designated ideal position and replace the native aortic valve to perform its function. However, during the implantation of the artificial valve, paravalvular leakage (PVL) can easily occur between the native valve tissue and the artificial valve stent, forming a blood flow leak between the artificial valve and the surrounding tissue. The causes of paravalvular leakage are varied. Besides unavoidable factors such as the inability to remove the patient's original degenerated, weakened, or damaged valve, and the patient's own anatomical structure (e.g., non-circular valve annulus plane), it is also closely related to the design characteristics of current transcatheter valve interventional devices. Multiple studies have shown that postoperative paravalvular leakage is directly related to the patient's recovery rate, reoperation rate, readmission rate, and early, mid, and long-term mortality.

[0004] Currently available balloon-expandable aortic valves typically have an external seal on the outside of the inflow end to improve paravalvular leakage by increasing the contact area with the cardiac valve annulus. However, these existing valve structures still have problems. Due to factors such as the implantation location of the artificial valve, differences in the anatomical structure of the natural aortic valve, and calcification, a certain amount of paravalvular leakage still exists after artificial valve implantation.

[0005] To prevent the balloon-expandable aortic valve from being implanted too high and subjected to the impact of blood flow, which could lead to displacement towards the ascending aorta, the inflow end of the artificial valve is typically positioned below the aortic valve annulus after expansion and deployment. Therefore, the outer skirt corresponding to the first set of circumferential mesh structures near the inflow end of the valve stent usually does not contact the surrounding valve tissue, further reducing the protective capability against paravalvular leakage in existing valve designs.

[0006] In view of the above problems, there is a need for an artificial aortic valve that can effectively prevent paravalvular leakage in order to improve the surgical prognosis of patients. Summary of the Invention

[0007] This invention discloses an artificial heart valve and a transcatheter heart valve replacement system, aiming to solve the technical problems existing in the prior art. The invention adopts the following technical solution:

[0008] In a first aspect, embodiments of the present invention provide an artificial heart valve, comprising:

[0009] - A valve stent has an inflow end and an outflow end. The valve stent has multiple circumferentially arranged grid groups arranged sequentially from the outflow end to the inflow end. The grid group closest to the inflow end is suitable for matching a position below the valve annulus plane. The mesh size of at least one set of non-end grid groups that matches the valve annulus plane is larger than the mesh size of at least one axially adjacent grid group.

[0010] - The outer skirt is covered on the outer surface of the valve stent. The outer skirt covers at least two adjacent sets of mesh near the inflow end, and the outer skirt is configured with a structure in which the thickness increases from the outflow end to the inflow end near the inflow end.

[0011] As a preferred technical solution, the valve stent includes a first grid group to an Nth grid group arranged sequentially from the outflow end to the inflow end, wherein N≥3;

[0012] The non-end mesh group corresponds to the position where it abuts against the surrounding tissue after implantation, and its mesh size is larger than the mesh size of the axially adjacent mesh group closest to the inflow end.

[0013] As a preferred technical solution, the valve stent includes a first grid group, a second grid group, a third grid group, and a fourth grid group arranged sequentially from the outflow end to the inflow end;

[0014] The third grid group corresponds to the position where it contacts the surrounding tissue after implantation, and the mesh size of the third grid group is larger than that of the second and fourth grid groups.

[0015] As a preferred technical solution, the outer skirt covers at least the third grid group and the fourth grid group, and the thickness of the outer skirt on the outer surface of the fourth grid group is greater than the thickness on the outer surface of the other grid groups.

[0016] As a preferred technical solution, the outer skirt covers at least the second to the fourth grid groups, and the thickness of the outer skirt on the outer surface of the third grid group is less than the thickness on the outer surface of the fourth grid group.

[0017] As a preferred technical solution, at least one side of the outer skirt corresponding to the third grid group is provided with a liquid-absorbing and expanding material. The liquid-absorbing and expanding material is configured to absorb blood and expand slowly after implantation to adapt to the valve annulus structure.

[0018] In the delivery state of the artificial heart valve, the liquid-absorbing and expanding material is compressed and arranged in the mesh opening of the third grid group to reduce the radial dimension of the artificial heart valve in the compressed state.

[0019] As a preferred technical solution, the liquid-absorbing and swelling material is arranged in the mesh area of ​​the third grid group, and the area opposite the support frame of the third grid group is provided with a thickness reduction area of ​​the liquid-absorbing and swelling material or an area without liquid-absorbing and swelling material.

[0020] As a preferred technical solution, the liquid-absorbing and swelling material includes bio-hydrogels.

[0021] As a preferred technical solution, it also includes an inner skirt, which is covered on the inner surface of the valve stent and is used to connect and support the artificial valve leaflet;

[0022] The inner skirt and the outer skirt together form an annular cavity, and the inner skirt is provided with a number of first openings distributed circumferentially, which are used to allow blood to flow into the annular cavity.

[0023] As a preferred technical solution, artificial valves include dried valves made from bovine or porcine pericardium.

[0024] As a preferred technical solution, the first opening is arranged in the area where the third grid group is located.

[0025] As a preferred technical solution, the outer side of the inner skirt and / or the inner side of the outer skirt in the area corresponding to the third grid group are provided with liquid-absorbing and swelling material.

[0026] As a preferred technical solution, the outer skirt corresponding to the area where the third grid group is located is provided with multiple second openings, and the second openings and the first openings are arranged alternately in the circumferential direction.

[0027] As a preferred technical solution, the second opening is configured such that when the valve stent is in a compressed state, the second opening is closed due to the tension of the outer skirt, so as to prevent blood from entering the annular cavity.

[0028] As a preferred technical solution, the second opening includes a partially overlapping leaflet structure. When the valve stent is in a compressed state, the leaflet structure covers each other to form a sealed structure. After the valve stent expands and releases, the leaflet structure separates to form an opening.

[0029] As a preferred technical solution, the first grid group is provided with three leaflet joint fixing windows along the circumference to fix the connection of adjacent artificial leaflets; the valve stent is also provided with three imaging marks, and the three imaging marks correspond one-to-one with the three leaflet joint fixing windows in the axial direction.

[0030] In a second aspect, embodiments of the present invention provide a transcatheter heart valve replacement system, including a delivery device and a releasable artificial heart valve connected to the distal end of the delivery device, wherein the artificial heart valve is an artificial heart valve as described in any of the preceding claims; the artificial heart valve is configured as a balloon-expandable artificial valve, suitable for transcatheter aortic valve replacement.

[0031] One embodiment of the above invention has the following advantages or beneficial effects:

[0032] This invention mainly provides an artificial heart valve and a transcatheter heart valve replacement system. By combining several grid structures on the valve stent with the outer skirt, it effectively solves the problems of paravalvular leakage and valve annulus mismatch in existing artificial heart valves.

[0033] In one embodiment of the present invention, the valve stent is provided with four sets of mesh structures from the outflow end to the inflow end. The third mesh set has a larger mesh size, which can provide more space for the outer skirt in the pleated state, so as to reduce the outer diameter of the artificial heart valve during delivery. In addition, the larger mesh size also reduces the interference of the stent skeleton with the adaptation of the outer skirt, so that the outer skirt can better fit the irregular or calcified tissue surface.

[0034] In one embodiment of the present invention, the outer skirt adopts a thickness gradient design, with the greatest thickness on the outer surface of the fourth grid group and a smaller thickness on the outer surface of the third grid group. This design avoids the inflow end of the valve stent from scratching surrounding tissues or the balloon during delivery; it also provides a buffering effect during the expansion of the artificial heart valve, preventing the apex of the inflow end from puncturing the balloon and causing valve implantation failure, thus reducing the risk of open-heart surgery to remove the valve; and it also improves the deformability and adaptability of the outer skirt at the position of the third grid group, enabling it to better adapt to the valve annulus anatomy of different patients.

[0035] In one embodiment of the present invention, the inner or outer side of the outer skirt is further provided with a liquid-absorbing and expanding material, which can absorb blood and expand slowly after release, thereby improving the fit between the artificial heart valve and the valve annulus. The liquid-absorbing and expanding material can also be compressed in the mesh during delivery, avoiding the problem of excessive compression size.

[0036] In one embodiment of the present invention, an inner skirt is further provided, which together with the outer skirt forms an annular cavity. The portion of the inner skirt corresponding to the third grid group is provided with a plurality of first openings, which facilitate the initial reflux of blood to enter the annular cavity through the first openings, forming a bulging sealing structure to fill irregular tissue gaps. By providing the first openings in the inner skirt, the risk of the outer skirt bulging prematurely due to accidental filling of blood during the delivery of the artificial heart valve can also be avoided.

[0037] As a balloon-expandable aortic valve, this invention is suitable for transcatheter aortic valve replacement. Its structural design can effectively enhance the sealing effect between the artificial heart valve and the original valve, reduce paravalvular leakage, thereby improving the implantation success rate and long-term effects, and providing a safer and more effective solution for clinical treatment. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below, forming part of the present invention. The illustrative embodiments of the present invention and their descriptions explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0039] Figure 1 This is a schematic diagram of the valve stent structure disclosed in one embodiment of the present invention;

[0040] Figure 2 This is a cross-sectional view of a valve stent disclosed in one embodiment of the present invention;

[0041] Figure 3 This is a schematic diagram of the structure of an artificial heart valve disclosed in one embodiment of the present invention;

[0042] Figure 4 for Figure 3 Front view;

[0043] Figure 5 for Figure 4 Sectional view along axis AA;

[0044] Figure 6 This is a schematic diagram of the structure of an artificial heart valve disclosed in one embodiment of the present invention;

[0045] Figure 7 for Figure 6 A sectional view;

[0046] Figure 8 This is a schematic diagram of the structure of an artificial heart valve disclosed in one embodiment of the present invention;

[0047] Figure 9 for Figure 8 A sectional view;

[0048] Figure 10 This is a schematic diagram of the structure of an artificial heart valve disclosed in one embodiment of the present invention;

[0049] Figure 11 for Figure 10 Cross-sectional view;

[0050] Figure 12 This is a schematic diagram of the structure of an artificial heart valve disclosed in one embodiment of the present invention;

[0051] Figure 13 for Figure 12 Front view;

[0052] Figure 14 for Figure 13 BB-direction sectional view;

[0053] Figure 15 This is a schematic diagram of the structure of an artificial heart valve disclosed in one embodiment of the present invention;

[0054] Figure 16 for Figure 15 A sectional view;

[0055] Figure 17 This is a schematic diagram of the structure of an artificial heart valve disclosed in one embodiment of the present invention;

[0056] Figure 18 This is a schematic diagram of the structure of an artificial heart valve disclosed in one embodiment of the present invention;

[0057] Figure 19 for Figure 18 Cross-sectional view.

[0058] Explanation of reference numerals in the attached figures:

[0059] Valve stent 10, first mesh group 11, leaflet joint fixation window 111, second mesh group 12, third mesh group 13, fourth mesh group 14, outer skirt 20, second opening 21, inner skirt 30, first opening 31, liquid-absorbing expansion material 40. Detailed Implementation

[0060] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. In the description of this invention, it should be noted that the term "or" is generally used to include the meaning of "and / or," unless otherwise expressly indicated.

[0061] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. Furthermore, in the description of this application, the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance. The term "proximal end" refers to the end along the length of the artificial heart valve or delivery device, closer to the operator; the term "distal end" refers to the end along the length of the artificial heart valve or delivery device, farther from the operator.

[0062] Those skilled in the art will understand that, in order to achieve their respective functions and meet the requirements of surgical procedures, the specific shape, size, angle, etc., of each structure can be adaptively adjusted. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present invention.

[0063] To address the technical problems existing in the prior art, in one embodiment of the present invention, an artificial heart valve is provided, preferably suitable for transcatheter aortic valve replacement, and preferably configured as a balloon-expandable artificial valve. The valve stent 10 is made of medical stainless steel or cobalt-chromium alloy by laser cutting. The artificial heart valve can be delivered to the target position by compression through a delivery catheter, and the radial expansion and anchoring of the valve stent 10 is achieved by balloon expansion. After the balloon expansion is completed, the balloon retracts and is withdrawn, while the artificial heart valve remains in the expanded state and fixed at the target position, supporting the normal opening and closing of the artificial valve leaflet and restoring the unidirectional blood flow function of the heart.

[0064] Compared to self-expanding artificial valves, balloon-expandable artificial valves are easier to position and can reduce the risk of valve displacement. In addition, they expand more evenly during deployment and can apply greater radial force, making the natural valve annulus closer to the ideal circle, thereby reducing the incidence of paravalvular leakage. They are especially suitable for patients with calcification or specific anatomical structures (such as transverse heart).

[0065] like Figures 3-5 In some embodiments, the artificial heart valve includes a valve stent 10 and an outer skirt 20. The valve stent 10 is configured in a compressed state during delivery and inflated into an expanded state by a balloon after release. After radial expansion, the axial length of the valve stent 10 is shortened, and its outline is cylindrical. The outer skirt 20 is a membrane material, such as PET or ePTFE, which is applied to the outer surface of the valve stent 10 to fit against the valve annulus to reduce paravalvular leakage.

[0066] refer to Figure 1 , Figure 2 In some embodiments, the valve stent 10 has an inflow end and an outflow end along its axial direction. Taking aortic valve replacement as an example, after the artificial heart valve is released in the heart, the inflow end corresponds to the left ventricular side for blood pumping in, and the outflow end corresponds to the aortic side for blood pumping out. The valve stent 10 is provided with multiple circumferentially arranged grid groups from the outflow end to the inflow end. Each grid group includes several interconnected polygonal grid structures, and each grid structure encloses a mesh opening. Adjacent grid structures are preferably connected by wave rods or nodes. The polygonal grid can be selected from rhomboid, pentagonal, hexagonal, or other units that can form a closed shape. The grid structures in the same grid group preferably have the same polygonal shape, and the grid structures in adjacent grid groups can be selected from the same or different polygonal shapes.

[0067] In some embodiments, the mesh group closest to the inflow end is adapted to be positioned below the annular plane, and the specific release depth can be adjusted according to clinical needs and the patient's specific anatomy. When the mesh group closest to the inflow end is positioned below the annular plane, this configuration provides a more stable anchoring effect, preventing the artificial heart valve from shifting towards the aorta due to blood flow impact after implantation, thus enhancing the positional stability of the artificial heart valve.

[0068] In some embodiments, the mesh size of at least one set of non-end mesh groups is larger than the mesh size of at least one axially adjacent mesh group. The larger mesh size can provide more accommodating space for the outer skirt 20 in the pleated state, thereby reducing the outer diameter of the artificial heart valve during delivery. In addition, the larger mesh size also reduces the interference of the stent skeleton with the adaptation of the outer skirt 20, allowing the outer skirt 20 to better fit irregular or calcified tissue surfaces.

[0069] In some embodiments, the outer skirt 20 covers at least two adjacent sets of mesh groups near the inflow end. These mesh groups correspond to the areas that are in contact with the annular tissue and below the annular plane. Covering the outer skirt 20 at least in these areas can prevent paravalvular leakage.

[0070] In some embodiments, the outer skirt 20 is configured with a thickness that increases from the outflow end to the inflow end near the inflow end. Since the mesh group here is located below the annulus plane, it does not come into contact with the tissue when it is below the annulus plane, so increasing the thickness of the corresponding outer skirt 20 does not increase the risk of conduction block. Secondly, the mesh vertices at the inflow end are relatively sharp, and the thickened outer skirt 20 can effectively cover these vertices, avoiding scratching the surrounding tissue or balloon during delivery. In addition, during the artificial heart valve expansion, the outer skirt 20 here changes from a taut state to a loosely stacked state, which can provide a buffering effect and prevent the mesh vertices from puncturing the balloon, resulting in artificial heart valve implantation failure.

[0071] In some embodiments, the outer skirt 20 corresponding to the mesh group that directly contacts the valve annulus is configured to have a thinner thickness to enhance its deformability and adaptability, so as to facilitate fitting the irregular valve annulus surface; the mesh group preferably corresponds to the non-end mesh group with a larger mesh opening mentioned above. The thinner outer skirt 20 thickness and the relatively larger mesh opening size here can greatly reduce the risk of cardiac conduction block when it comes into contact with the valve annulus tissue, thus avoiding the implantation of a permanent pacemaker for the patient.

[0072] In some embodiments, the valve stent 10 includes a first grid group 11 to a Nth grid group arranged sequentially from the outflow end to the inflow end, wherein N≥3; the non-end grid group corresponds to the position that abuts against the surrounding tissue after implantation, and its mesh size is larger than the mesh size of the axially adjacent grid group closest to the inflow end.

[0073] Specifically, N can take values ​​of 3, 4, 5, or more. Different N values ​​correspond to different axial distribution densities of the grid groups. A larger N value indicates a denser grid arrangement along the axial direction of the valve stent 10, providing more refined mechanical performance zoning. Conversely, a smaller N value indicates a looser grid arrangement along the axial direction of the valve stent 10, with each grid group having a relatively larger axial span, thus achieving a larger mesh size while ensuring the overall strength of the valve stent 10. When multiple grid groups simultaneously abut against surrounding tissue after implantation, these non-end grid groups abutting against the tissue can be configured to have a larger mesh size to improve tissue adhesion.

[0074] like Figure 2 In some embodiments, N is 4, that is, the valve stent 10 includes a first grid group 11, a second grid group 12, a third grid group 13 and a fourth grid group 14 arranged sequentially from the outflow end to the inflow end. The third grid group 13 corresponds to the position that abuts against the surrounding tissue after implantation, that is, the position of the valve annulus plane, and the fourth grid group 14 corresponds to the position of the left ventricular outflow tract below the valve annulus. The mesh size of the third grid group 13 is preferably larger than the mesh size of the second grid group 12 and the fourth grid group 14, so as to reduce the interference of the outer skirt 20 of the stent skeleton fitting at this point, so that the outer skirt 20 can more fully adapt to the irregular or calcified valve annulus surface.

[0075] In some embodiments, the outer skirt 20 covers at least the third grid group 13 and the fourth grid group 14, and the thickness of the outer skirt 20 on the outer surface of the fourth grid group 14 is greater than the thickness on the outer surfaces of the other grid groups. The thickness of the outer skirt 20 can be configured in two different ways: one is that it increases continuously along the direction from the third grid group 13 to the fourth grid group 14; the other is that the outer skirt 20 corresponding to the third grid group 13 maintains a uniform thickness, and the outer skirt 20 corresponding to the fourth grid group 14 also maintains a uniform thickness, but the thickness of the outer skirt 20 on the outer surface of the fourth grid group 14 is greater than the thickness of the outer skirt 20 on the outer surface of the third grid group 13.

[0076] like Figures 3-5In some embodiments, the outer skirt 20 covers at least the second grid group 12 to the fourth grid group 14 to further improve the overall sealing performance of the artificial heart valve, especially for patients with anatomical variations or uneven calcification distribution. The expanded coverage allows the outer skirt 20 to form a sealing contact with a larger area of ​​surrounding tissue, reducing the risk of paravalvular leakage. Preferably, the thickness of the outer skirt 20 on at least the outer surface of the third grid group 13 is less than the thickness on the outer surface of the fourth grid group 14. The thickness configuration of the outer skirt 20 can adopt a continuous transition structure that gradually increases from the second grid group 12 to the fourth grid group 14, or the outer skirt 20 corresponding to the second grid group 12 and the third grid group 13 can maintain a uniform thickness, but the transition structure between them and the fourth grid group 14 can be a stepped increase.

[0077] In some embodiments, the upper edge of the outer skirt 20 can be set along the edge of the mesh, such as... Figures 3-5 Alternatively, it can be set straight along the circumference of the valve stent 10, such as... Figure 6 and Figure 7 At this point, the upper edge of the outer skirt 20 may cover only half or other proportions of the axial length of the second grid group 12.

[0078] In some embodiments, the outer skirt 20 corresponding to the third mesh group 13 is further provided with a liquid-absorbing and swelling material 40, which can be disposed on the outer side of the outer skirt 20, such as... Figure 8 and Figure 9 It can also be set on the inside, such as Figure 10 , Figure 11 The absorbent swelling material 40 is configured to absorb blood and adaptively expand slowly after implantation.

[0079] Once the artificial heart valve is deployed to the target location, the absorbent expansion material 40 gradually absorbs the surrounding blood, increases in volume, and fills the gap between the valve stent 10 and the irregular calcified tissue. Combined with the excellent deformation properties of the outer skirt 20 in this section, it can further form a sufficient seal with the surrounding irregularly shaped calcified tissue. This is of great significance for reducing the risk of paravalvular leakage in patients with severe calcification of the valve annulus and leaflets.

[0080] In some embodiments, when the artificial heart valve is compressed and loaded into the delivery system, the absorbent expansion material 40 is compressed and arranged in the mesh opening of the third mesh group 13. This effectively utilizes the mesh opening space and reduces the radial dimension of the artificial heart valve in the compressed state. Furthermore, this arrangement ensures the stability of the absorbent expansion material 40 during delivery, preventing premature contact with blood and expansion, or detachment due to shear forces. When the artificial heart valve is inflated and released by the balloon, the absorbent expansion material 40 compressed in the mesh opening unfolds, restoring its original structure and preparing to perform its sealing function.

[0081] like Figure 8 , Figure 9 In some embodiments, the liquid-absorbing and swelling material 40 is arranged in the mesh area of ​​the third mesh group 13, and the area opposite the support frame of the third mesh group 13 is provided with a thickness reduction area of ​​the liquid-absorbing and swelling material 40 or an area without the liquid-absorbing and swelling material 40.

[0082] Specifically, the stent skeleton itself is in direct contact with the tissue and provides radial support. These areas are typically not major paravalvular leakage pathways, therefore requiring little or no absorbent expansion material 40. The mesh area, however, is a potential paravalvular leakage pathway, requiring more absorbent expansion material 40 to form an effective seal. Secondly, thinning or eliminating the absorbent expansion material 40 in the stent skeleton areas reduces the thickness of the cover on the skeleton struts, helping to further reduce the overall diameter of the artificial heart valve under compression. In actual manufacturing, this regionalized material distribution can be achieved through processes such as precision coating, molding, or hot pressing, ensuring that the absorbent expansion material 40 provides optimal sealing in critical locations while maintaining the compactness and compressibility of the overall structure.

[0083] In some embodiments, the liquid-absorbing and swelling material 40 includes a bio-hydrogel, which is a three-dimensional network structure composed of hydrophilic polymer chains capable of absorbing large amounts of water in an aqueous environment without dissolving, while maintaining structural integrity. After liquid absorption and swelling, the resulting soft elastomer can dynamically adapt to morphological changes in surrounding tissues, providing a continuous sealing effect, particularly during cardiac contraction and relaxation.

[0084] In some embodiments, the expansion rate and expansion ratio can be controlled by adjusting the degree of chemical crosslinking of the bio-hydrogel, thereby precisely matching clinical needs. In this embodiment, a bio-hydrogel formulation with slow expansion kinetics is preferred. By controlling the crosslinking reaction parameters, the hydrogel exhibits a gradual expansion behavior within several hours after contact with blood, allowing surrounding tissues sufficient time to adapt to the morphological changes. Simultaneously, hemodynamic parameters remain stable, avoiding the application of sudden mechanical pressure to the valve annulus tissue, which could induce or exacerbate heart failure in patients. Furthermore, this slow expansion characteristic promotes gradual adaptation and integration between the bio-hydrogel and surrounding tissues, forming a more stable long-term sealing interface. In this embodiment, the specific expansion rate and expansion ratio of the bio-hydrogel are not limited; those skilled in the art can make adaptive selections based on the actual needs of the patient and clinicians.

[0085] like Figures 12-14In some embodiments, the artificial heart valve also includes an inner skirt 30, which may be made of the same membranous material as the outer skirt 20. The inner skirt 30 is covered on the inner surface of the valve stent 10 and is used to connect to and support the artificial leaflet (the shape of the artificial leaflet is not shown further in the figure for clarity of the structure).

[0086] Clinically used bioprosthetic valves are usually stored in glutaraldehyde solution. Glutaraldehyde can not only kill microorganisms, but also has a good cross-linking effect, which makes the biomembrane structure stable. However, at the same time, there are also the following problems: aldehyde groups cause bioprosthetic valves to calcify, affecting their service life; bioprosthetic valves are inconvenient to store and have high transportation costs; and they need to be rinsed before clinical use, which is a complicated operation.

[0087] To avoid the aforementioned problems, in some embodiments, the artificial valve leaflets are preferably dried leaflets made from bovine or porcine pericardium. Compared to traditional wet bioprosthetic valves, dried leaflets have advantages such as convenient storage, low transportation costs, and no need for rinsing before clinical use. Furthermore, by avoiding prolonged immersion in glutaraldehyde solution, the risk of calcification caused by aldehyde groups is effectively reduced, potentially extending the valve's lifespan while maintaining good hemodynamic performance.

[0088] In some embodiments, the inner skirt 30 and the outer skirt 20 enclose each other to form an annular cavity. Specifically, the inner skirt 30 and the outer skirt 20 may be an integral structure or a separate structure connected by stitching; the coverage area of ​​the inner skirt 30 inside the valve stent 10 includes at least the third mesh group 13 to the fourth mesh group 14, so as to ensure that the annular cavity formed by the inner skirt 30 and the outer skirt 20 can correspond to the position of the valve annulus, so as to ensure the seal of the valve annulus.

[0089] The upper edge of the outer skirt 20 can adopt a flat structure along the circumference of the valve stent 10, such as... Figure 18 , Figure 19 It can also be configured as a wavy profile along the direction of the grid structure, such as... Figures 15-17 The upper edge of the inner skirt 30 can also adopt a flat or wavy contour. The upper edges of the inner skirt 30 and the outer skirt 20 can adopt the same or different contours. The suture fixation points of the outer skirt 20 / inner skirt 30 and the valve stent 10 can be flexibly configured according to specific sealing requirements and the structure of the valve stent 10. The core purpose is to ensure that the outer skirt 20 can form a controlled protruding sealing structure radially due to the blood flowing into the annular cavity during the expansion of the valve stent 10 by the balloon, so as to improve the adaptability to irregular valve annular morphology.

[0090] In some embodiments, the inner skirt 30 is provided with a plurality of first openings 31 distributed circumferentially, the first openings 31 being used to allow blood to flow into the annular cavity, such as... Figure 15 , Figure 16 .

[0091] In some embodiments, the first openings 31 are distributed uniformly or non-uniformly along the circumference, and preferably are arranged correspondingly in the region where the third grid is located, such that the annular cavity corresponds to the valve annulus plane. When the valve closes during diastole, several first openings 31 allow regurgitated blood to enter the annular cavity through a controlled pathway, thereby causing the outer side of the annular cavity to present a radial bulge state, effectively filling the irregular gaps or calcified depressions around the valve annulus, forming a dynamically adaptive sealing structure.

[0092] Specifically, during the delivery of the artificial heart valve, the outer skirt 20 is directly exposed to the blood flow environment. If the outer skirt 20 has an opening, blood may enter the annular cavity before the artificial heart valve reaches the target position, causing the outer skirt 20 to expand prematurely. This situation not only increases the resistance of the delivery system, but may also cause valve positioning deviation or damage to the blood vessel wall. By setting the first opening 31 only in the inner skirt 30, it can be ensured that the annular cavity can only be filled with blood after the artificial heart valve is fully released and begins to work, thereby achieving a controllable timing activation sealing mechanism.

[0093] In some embodiments, the inner skirt 30 is preferably made of a material with a lower elastic modulus, or has a smaller coverage size compared to the outer skirt 20. When the balloon dilates and releases the valve stent 10 to the target diameter, the material of the inner skirt 30 is stretched to near its elastic limit, forming a highly pre-tensioned membrane structure. When diastolic blood enters the annular cavity through the first opening 31 of the inner skirt 30, the outer skirt 20, due to its higher elasticity and compliance, can flexibly expand radially outward, forming an effective sealing barrier, while the inner skirt 30 maintains a stable shape. This avoids a reduction in the effective valve area (EOA) caused by the inward expansion of the inner skirt 30, which would increase the transvalvular pressure gradient and potentially interfere with the normal opening and closing function of the valve leaflets. By ensuring that the inner skirt 30 maintains a stable shape, the geometric continuity and hydrodynamic performance of the blood flow channel are effectively guaranteed, while still allowing the outer skirt 20 to fully perform its sealing function, forming a dynamic adaptation to irregular valve annular tissue.

[0094] In other embodiments, the outer side of the inner skirt 30 corresponding to the third mesh group 13 is provided with a liquid-absorbing and swelling material 40, such as... Figure 17 As shown by the dotted lines, and / or the area corresponding to the third grid group 13, the inner side of the outer skirt 20 is provided with a liquid-absorbing and swelling material 40, such as... Figure 18 , Figure 19 Preferably, the outer skirt 20 corresponding to the area where the third grid group 13 is located is provided with a plurality of second openings 21 to increase the opportunity for the liquid-absorbing and swelling material 40 to come into contact with blood; the second openings 21 are preferably staggered with the first openings 31 in the circumferential direction to avoid blood from flowing directly between them, thereby ensuring that the liquid-absorbing and swelling material 40 can fully come into contact with blood and perform its function.

[0095] Specifically, the outer side of the inner skirt 30 and the inner side of the outer skirt 20 in the region corresponding to the third grid group 13 essentially define the internal space of the annular cavity. Therefore, the absorbent swelling material 40 is actually configured inside the annular cavity to ensure that the absorbent swelling material 40 inside the annular cavity can efficiently absorb blood and lock it inside the cavity, forming a dynamically adaptive sealing system. It also transmits pressure outward through the outer skirt 20, effectively and actively filling the irregular gaps and tiny crevices around the valve annulus, significantly reducing the risk of paravalvular leakage.

[0096] In some embodiments, the second opening 21 is configured such that when the valve stent 10 is in a compressed state, the second opening 21 is closed due to the tension on the outer skirt 20, so as to prevent blood from entering the annular cavity.

[0097] Specifically, when the valve stent 10 is in a radially compressed state within the delivery system, the outer skirt 20 is subjected to high axial tension. This axial tension tightens the second opening 21, causing it to close laterally. This effectively blocks the possibility of blood entering the annular cavity through the second opening 21, thus avoiding delivery difficulties or positioning deviations caused by premature valve volume increase. When the valve stent 10 is expanded and released to the target diameter via balloon dilation, the axial tension of the outer skirt 20 decreases significantly. At this time, the second opening 21 automatically opens, allowing blood to enter the annular cavity and contact the absorbent expansion material 40 to activate the sealing function.

[0098] In some embodiments, the second opening 21 includes partially overlapping flap structures that cover each other to form a sealed structure when the valve stent 10 is in a compressed state, and that separate to form an opening after the valve stent 10 expands and releases.

[0099] Specifically, the flaps are configured in a semi-elliptical or crescent shape, with their long axis aligned with the principal stress direction of the valve stent 10 under compression. The overlapping area of ​​the flaps functions similarly to the placket and lining structure in clothing. When the valve stent 10 is compressed, the circumferential contraction of the entire artificial valve causes these flaps to overlap to a greater extent, forming a barrier structure that effectively prevents blood infiltration. When the valve stent 10 begins to expand, the circumferential tension decreases, and the overlapping area between the flaps gradually decreases until, in the fully released state, the flap structure automatically separates along a preset separation line, forming a clear opening profile to allow blood to flow from the external environment into the annular cavity.

[0100] like Figure 1In some embodiments, the first grid group 11 is provided with three leaflet joint fixation windows 111 along the circumferential direction for fixing the connection of adjacent artificial leaflets; the valve stent 10 is also provided with three imaging marks, which correspond one-to-one with the three leaflet joint fixation windows 111 in the axial direction, for alignment with the junction of the original leaflet under intraoperative X-ray fluoroscopy, to avoid the artificial leaflet from blocking the coronary artery opening, thereby reducing the risk of postoperative coronary artery occlusion.

[0101] Specifically, the imaging markers can be placed on the stent structure, or at corresponding positions on the outer skirt 20 or inner skirt 30. They can be made of biocompatible materials with good X-ray impermeability, such as tantalum or platinum-iridium alloy, and can be dot-shaped, ring-shaped, or line-shaped to facilitate accurate identification during surgery. Compared with existing technologies, the above embodiments provide a solution that effectively enhances the sealing effect between the artificial heart valve and the original valve, reduces paravalvular leakage, thereby improving the implantation success rate and long-term effects, and providing a safer and more effective solution for clinical treatment.

[0102] In another embodiment of the present invention, a transcatheter heart valve replacement system is also provided, including a delivery device and the aforementioned artificial heart valve, wherein the artificial heart valve is releasably connected to the distal end of the delivery device and is preferably configured as a balloon-expandable artificial valve, suitable for transcatheter aortic valve replacement.

[0103] Because the artificial heart valve of this invention maintains compatibility with existing technologies in key parameters such as peripheral contour dimensions, stent contraction-expansion characteristics, and proximal-distal connection structure, the delivery device in this embodiment can adopt any technical solution from existing mature transcatheter valve delivery systems. The specific structural form of the delivery device does not constitute a limiting technical feature of this invention and can be selected according to clinical needs, surgical approach (e.g., via the femoral artery, apex, or aorta), and operator preference. The technological innovation of this invention is mainly reflected in the artificial heart valve structure itself, particularly its anti-paravalvular leak design, while the delivery device is designed with functional interoperability as its principle, ensuring seamless integration with existing clinical workflows, reducing the learning curve and clinical adoption threshold.

[0104] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of this application. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of this application. All such changes and modifications are intended to be included within the scope of this application as claimed in the appended claims.

Claims

1. An artificial heart valve, characterized in that, include: - A valve stent, the valve stent having an inflow end and an outflow end, the valve stent having a plurality of circumferentially arranged grid groups arranged sequentially from the outflow end to the inflow end, wherein the grid group closest to the inflow end is suitable for matching below the valve annulus plane to enhance the anchoring effect and prevent the artificial heart valve from shifting due to blood flow impact after implantation, and at least one set of non-end grid groups matching the valve annulus plane has a mesh opening size larger than the mesh opening size of at least one axially adjacent grid group; - The outer skirt is configured as a single-layer membrane structure and is covered on the outer surface of the valve stent. The outer skirt covers at least two adjacent sets of mesh groups near the inflow end. The outer skirt is configured near the inflow end to have a structure in which the thickness increases from the outflow end to the inflow end. The thickened outer skirt covers the grid vertices of the inflow end. The outer skirt is taut during delivery to avoid scratching surrounding tissues or the balloon during delivery. When the artificial heart valve expands, it becomes loosely stacked to provide cushioning for the grid vertices of the inflow end. The outer skirt corresponding to the non-end mesh group that is in direct contact with the valve annulus is configured with a thinner thickness to enhance its deformability and fit to the irregular valve annulus surface. The thinner outer skirt thickness and the relatively large mesh size of the covered non-end mesh group reduce the risk of cardiac conduction block when it comes into contact with the valve annulus tissue.

2. The artificial heart valve according to claim 1, characterized in that, The valve stent includes a first grid group to an Nth grid group arranged sequentially from the outflow end to the inflow end, wherein N≥3; The non-end mesh group corresponds to the position that abuts against the surrounding tissue after implantation, and its mesh size is larger than the mesh size of the axially adjacent mesh group closest to the inflow end.

3. The artificial heart valve according to claim 2, characterized in that, The valve stent includes a first grid group, a second grid group, a third grid group, and a fourth grid group arranged sequentially from the outflow end to the inflow end; The third grid group corresponds to the position where it contacts the surrounding tissue after implantation, and the mesh size of the third grid group is larger than that of the second grid group and the fourth grid group.

4. The artificial heart valve according to claim 3, characterized in that, The outer skirt covers at least the third grid group and the fourth grid group, and the thickness of the outer skirt on the outer surface of the fourth grid group is greater than the thickness on the outer surfaces of the other grid groups.

5. The artificial heart valve according to claim 4, characterized in that, The outer skirt covers at least the second to the fourth grid groups, and the thickness of the outer skirt on the outer surface of the third grid group is less than the thickness on the outer surface of the fourth grid group.

6. The artificial heart valve according to claim 5, characterized in that, At least one side of the outer skirt corresponding to the third grid group is provided with a liquid-absorbing and swelling material, which is configured to absorb blood and slowly expand after implantation to adapt to the valve annulus structure. In the delivery state of the artificial heart valve, the liquid-absorbing and swelling material is compressed and arranged in the mesh opening of the third mesh group to reduce the radial dimension of the artificial heart valve in the compressed state.

7. The artificial heart valve according to claim 6, characterized in that, The liquid-absorbing and swelling material is arranged in the mesh area of ​​the third grid group. The area opposite the support frame of the third grid group is a thinning area of ​​the liquid-absorbing and swelling material or an area without liquid-absorbing and swelling material.

8. The artificial heart valve according to claim 6, characterized in that, The liquid-absorbing and swelling material includes a bio-hydrogel.

9. The artificial heart valve according to claim 4, characterized in that, It also includes an inner skirt, which covers the inner surface of the valve stent and is used to connect to and support the artificial valve leaflet; The inner skirt and the outer skirt together form an annular cavity, and the inner skirt is provided with a plurality of first openings distributed circumferentially, the first openings being used to allow blood to flow into the annular cavity.

10. The artificial heart valve according to claim 9, characterized in that, The artificial leaflets include dried leaflets made from bovine or porcine pericardium.

11. The artificial heart valve according to claim 9, characterized in that, The first opening is located in the area where the third grid group is located.

12. The artificial heart valve according to claim 11, characterized in that, Liquid-absorbing and swelling material is provided on the outer side of the inner skirt and / or the inner side of the outer skirt in the area corresponding to the third grid group.

13. The artificial heart valve according to claim 12, characterized in that, The outer skirt corresponding to the area where the third grid group is located is provided with multiple second openings, and the second openings and the first openings are arranged alternately in the circumferential direction.

14. The artificial heart valve according to claim 13, characterized in that, The second opening is configured such that when the valve stent is in a compressed state, the second opening is closed due to the tension on the outer skirt, so as to prevent blood from entering the annular cavity.

15. The artificial heart valve according to claim 14, characterized in that, The second opening includes partially overlapping flap structures that cover each other to form a sealed structure when the valve stent is in a compressed state, and that separate to form an opening after the valve stent expands and releases.

16. The artificial heart valve according to claim 9, characterized in that, The first grid group is provided with three leaflet joint fixing windows along the circumference, which are used to fix the connection of adjacent artificial leaflets; The valve stent is also provided with three imaging marks, and the three imaging marks correspond one-to-one with the three leaflet joint fixing windows in the axial direction.

17. A transcatheter heart valve replacement system, comprising a delivery device and a releasable artificial heart valve connected to a distal end of said delivery device, characterized in that, The artificial heart valve is the artificial heart valve as described in any one of claims 1-16; the artificial heart valve is configured as a balloon-expandable artificial valve, suitable for transcatheter aortic valve replacement.

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