Valve stent and valve prosthesis

Abstract

The application provides a valve stent and a valve prosthesis, the valve stent comprising an outer layer stent, an inner layer stent and at least one buffer part; the outer layer stent is sleeved outside the inner layer stent and is connected with the inner layer stent through the buffer part. The buffer part can effectively reduce the influence of the deformation of the outer layer stent on the opening and closing of the valve leaflet on the inner layer stent, so that the buffer part can significantly weaken or isolate the mutual force between the outer layer stent and the inner layer stent. In addition, the valve stent adopts the design of double-layer stent, which can effectively improve the fatigue resistance of the valve prosthesis, make the valve prosthesis more fit the original tissue, reduce the influence of the valve stent on the ventricular contraction capacity and ensure the stability of the closed valve stent.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a valve stent and a valve prosthesis. Background Technology

[0002] With socioeconomic development and an aging population, valvular heart disease, as well as valvular lesions caused by coronary heart disease and myocardial infarction, are becoming increasingly common. Studies show that over 13.3% of people over 75 years of age suffer from varying degrees of valvular heart disease. Heart valve disease has gradually become one of the major threats to human health. Mitral and tricuspid valve diseases are relatively common clinical heart valve diseases. The human heart consists of four chambers: the left atrium, left ventricle, right atrium, and right ventricle. The two atria are connected to the two ventricles, and the two ventricles are connected to the two aorta. The mitral valve is located between the left atrium and left ventricle and consists of leaflets, annulus, chordae tendineae, and papillary muscles, acting as a one-way valve to ensure unidirectional blood flow. At the right atrioventricular orifice, three triangular valves, called the tricuspid valve or right atrioventricular valve, are attached to a fibrous framework ring composed of dense connective tissue. The tricuspid valve acts like a "one-way valve," ensuring that blood circulation flows from the right atrium to the right ventricle and that a certain flow rate is achieved.

[0003] Mitral valve replacement is one of the effective treatments for mitral valve disease. Currently, the most common mitral valve prosthesis is the single-layer mitral valve prosthesis. After implantation, when the left ventricle relaxes and blood flows through the inflow tract, the leaflets open, and the single-layer mitral valve stent is only subjected to the squeezing force of the valve annulus. When the left ventricle contracts, the leaflets close, and due to blood pressure, the leaflets are subjected to pressure based on their area, which is borne by the single-layer mitral valve stent. The area of ​​the leaflets that need to be sutured in a single-layer mitral valve stent is equal to the cross-sectional area of ​​the stent. If the single-layer mitral valve stent is designed as a double-layer structure, with the skirt and leaflets sutured to the inner layer of the double-layer stent, the area of ​​the leaflets is reduced, thereby reducing the force that the inner stent needs to withstand when the leaflets close and improving the fatigue resistance of the inner stent. Furthermore, the mitral valve's native annulus folds during ventricular diastole and systole. However, after implantation of a single-layer mitral valve prosthesis, the native annulus needs to be stretched into the shape of a single-layer mitral valve stent to ensure proper leaflet closure. This leads to loss of native annulus movement and decreased ventricular contractility. If the single-layer mitral valve stent is designed as a double-layer stent, the outer layer can move with the native annulus, while the leaflets on the inner layer can still open and close normally. This maintains the movement of the native annulus, reducing the stent's impact on ventricular contractility and ensuring stable valve closure. Designing a double-layer mitral valve stent structure can also isolate the outer and inner layers from mutual interference to some extent. Of course, the principle of tricuspid valve replacement is similar to that of mitral valve replacement, and will not be elaborated here.

[0004] However, in current double-layer mitral valve stent structures, the inner and outer layers are generally connected by direct welding. During the opening and closing of the leaflets, both the outer and inner stent layers undergo significant deformation, affecting the fatigue resistance of the double-layer mitral valve stent. Therefore, the outer stent, moving with the native annulus, significantly influences the opening and closing of the leaflets on the inner stent. Consequently, the reduction in stress between the native annulus and leaflets by the outer and inner stent layers of the double-layer mitral valve stent is still insufficient, thus affecting ventricular contractility.

[0005] Therefore, developing a method that can significantly reduce or isolate the mutual forces between the outer and inner stent layers, reduce the impact of the valve stent on ventricular contractility, and improve the stability of valve stent closure has become an urgent problem to be solved. Summary of the Invention

[0006] The purpose of this invention is to provide a valve stent and a valve prosthesis to solve the problems of deformation caused by mutual stress between the outer and inner layers of the current valve stent, the significant impact of the valve stent on ventricular contractility, and the low stability of valve stent closure.

[0007] To solve the above-mentioned technical problems, the present invention provides a valve stent, comprising: an outer stent, an inner stent, and at least one buffer portion; the outer stent is sleeved outside the inner stent and connected to the inner stent through the buffer portion.

[0008] Optionally, the buffer portion includes at least one buffer structure, which includes at least one of a straight rod structure, an S-shaped bending structure, a Z-shaped bending structure, a square bending structure, or a trapezoidal bending structure.

[0009] Optionally, the buffer section further includes a connecting rod, and the buffer structure is connected to one or more of the outer support, the inner support, and other buffer structures via the connecting rod; the distance between the crests and troughs of the outer contour of the buffer structure is a second width, and the second width is not greater than the width of the connecting rod along the circumference of the valve support.

[0010] Optionally, the axis of the S-shaped curved structure extends in a wave shape, the buffer structure has a first width in the direction perpendicular to its own axis, the distance between the crest and trough of the outer contour of the buffer structure is a second width, and the first width is between one-quarter and one-half of the second width.

[0011] Optionally, the S-shaped curved structure includes a first straight segment, a first curved segment, a second straight segment, a second curved segment, and a third straight segment connected in sequence. The first straight segment, the second straight segment, and the third straight segment are straight, and the first curved segment and the second curved segment are curved. The curvature of the first curved segment and the second curved segment are the same.

[0012] Optionally, the first straight segment, the second straight segment, and the third straight segment are arranged parallel to each other, and the first straight segment, the second straight segment, and the third straight segment are perpendicular to the axis of the valve stent.

[0013] Optionally, the first curved segment and the second curved segment are semi-circular ring structures, the buffer structure has a first width in the direction perpendicular to its own axis, and the inner diameter of the semi-circular ring structure is between one-quarter and one-half of the first width.

[0014] Optionally, the buffer portion is disposed on the outer support.

[0015] Optionally, the inner stent has a valve connection portion, and the buffer structure of the buffer portion connected to the valve connection portion has a first length along the extension direction of the buffer portion, and the remaining buffer structures of the buffer portion have a second length along the extension direction of the buffer portion, wherein the first length is longer than the second length.

[0016] Optionally, the extension direction of the buffer portion is set at an angle to the axial direction of the valve stent.

[0017] Optionally, the valve stent has a valve stent length along its own axial direction, and the length of the buffer portion projected along the axial direction of the valve stent accounts for 20% to 30% of the valve stent length.

[0018] Optionally, the valve stent further includes stent lugs, and the buffer portion is connected to the inner stent via the stent lugs.

[0019] Optionally, the outer stent and the inner stent are connected along the outflow end of the valve stent via the buffer portion.

[0020] Optionally, the outer support includes a flange, an outer support body, and barbs. The flange is connected to one axial end of the support body, and the barbs are located on the grid nodes of the outer support body and extend toward the flange end.

[0021] To address the aforementioned technical problems, the present invention also provides a valve prosthesis, comprising: a valve stent, leaflets, and a skirt as described above; the leaflets and the skirt are respectively disposed on the valve stent.

[0022] In a valve stent and valve prosthesis provided by this invention, the valve stent includes an outer stent, an inner stent, and at least one buffer portion. The outer stent is sleeved over the inner stent and connected to the inner stent via the buffer portion. The buffer portion effectively reduces the impact of deformation of the outer stent on the opening and closing of the leaflets on the inner stent, thereby significantly reducing or isolating the mutual stress between the outer and inner stents. Furthermore, the valve stent employs a double-layer stent design, which effectively enhances the fatigue resistance of the valve prosthesis, allows for a closer fit between the valve prosthesis and the native tissue, reduces the impact of the valve stent on ventricular contractility, and ensures stable valve closure. Attached Figure Description

[0023] Those skilled in the art will understand that the accompanying drawings are provided to better understand the invention and do not constitute any limitation on the scope of the invention. Wherein:

[0024] Figure 1 This is a schematic diagram of a valve stent according to an embodiment of the present invention.

[0025] Figure 2 for Figure 1 The diagram shows the outer layer of the valve stent.

[0026] Figure 3 This is a schematic diagram of an S-shaped bending structure according to an embodiment of the present invention.

[0027] Figure 4 This is a schematic diagram of the Z-shaped bending structure according to an embodiment of the present invention.

[0028] Figure 5 This is a schematic diagram of a square curved structure according to an embodiment of the present invention.

[0029] Figure 6 This is a schematic diagram of a trapezoidal bending structure according to an embodiment of the present invention.

[0030] Figure 7 This is a schematic diagram of the support grid of the outer support body in an embodiment of the present invention.

[0031] Figure 8 This is a schematic diagram of another type of support grid for the outer support body according to an embodiment of the present invention.

[0032] Figure 9 This is a schematic diagram of the outer support hanging ear according to an embodiment of the present invention.

[0033] Figure 10 This is a schematic diagram of the inner stent of the valve stent according to an embodiment of the present invention.

[0034] In the attached image:

[0035] h1 - First width, h2 - Second width;

[0036] A - Extension direction of the buffer section, B - Axis of the valve stent, α - Angle between the extension direction of the buffer section and the axis of the valve stent;

[0037] 100 - Outer support, 110 - Flange, 120 - Outer support body, 130 - Barb;

[0038] 200 - Inner support layer, 210 - Main body of the inner support layer;

[0039] 300 - Buffer section, 300a - Buffer structure, 300b - Connecting rod;

[0040] 310 - S-shaped curved structure; 311 - First straight segment; 312 - First curved segment; 313 - Second straight segment; 314 - Second curved segment; 315 - Third straight segment.

[0041] 320-Z-type bending structure, 330-square bending structure, 340-trapezoidal bending structure;

[0042] 400 - Bracket hook, 410 - Inner and outer bracket hook, 420 - Outer bracket hook. Detailed Implementation

[0043] To make the objectives, advantages, and features of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to facilitate and clarify the explanation of the embodiments of this invention. Furthermore, the structures shown in the drawings are often part of the actual structures. In particular, different figures may emphasize different aspects and may sometimes use different scales.

[0044] As used herein, the singular forms “a,” “an,” and “the” include plural objects unless otherwise expressly indicated. As used herein, the term “or” is generally used to include “and / or” unless otherwise expressly indicated. The term “a number” is generally used to include “at least one,” and the term “at least two” is generally used to include “two or more.” Furthermore, the terms “first,” “second,” and “third” are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as “first,” “second,” or “third” may explicitly or implicitly include one or at least two of that feature. The terms “installed,” “connected,” and “joined” should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral part; they may refer to a direct connection or an indirect connection through an intermediate medium; they may refer to the internal communication of two components or the interaction between two components. “Distal end” refers to the end furthest from the medical staff's operation, and “proximal end” refers to the end closest to the medical staff's operation. Furthermore, as used in this invention, the phrase "one element disposed on another element" generally only indicates a connection, coupling, cooperation, or transmission relationship between the two elements, and this connection, coupling, cooperation, or transmission can be direct or indirect through an intermediate element. It should not be construed as indicating or implying a spatial positional relationship between the two elements, i.e., one element can be located arbitrarily inside, outside, above, below, or to one side of another element, unless otherwise explicitly stated. Those skilled in the art will understand the specific meaning of the above terms in this invention according to the specific circumstances. Additionally, numerous specific details are set forth in the following description to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with this invention.

[0045] This invention provides a valvular stent and a valvular prosthesis. The valvular stent includes an outer stent, an inner stent, and at least one buffer portion. The outer stent is fitted over the inner stent and connected to it via the buffer portion. The buffer portion effectively reduces the impact of deformation of the outer stent on the opening and closing of the leaflets on the inner stent, thereby significantly reducing or isolating the mutual stress between the outer and inner stents. Furthermore, the valvular stent employs a double-layer stent design, which effectively enhances the fatigue resistance of the valvular prosthesis, allows for a closer fit between the prosthesis and the native tissue, reduces the impact of the valvular stent on ventricular contractility, and ensures stable valve closure.

[0046] The following description refers to the accompanying drawings.

[0047] Figure 1 This is a schematic diagram of a valve stent according to an embodiment of the present invention; Figure 2 for Figure 1 A schematic diagram of the outer layer of the valve stent shown; Figure 3 This is a schematic diagram of the S-shaped bending structure according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the Z-shaped bending structure according to an embodiment of the present invention; Figure 5 This is a schematic diagram of a square curved structure according to an embodiment of the present invention; Figure 6 This is a schematic diagram of a trapezoidal bending structure according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the support grid of the outer support body according to an embodiment of the present invention; Figure 8 This is a schematic diagram of another type of support grid for the outer support body according to an embodiment of the present invention; Figure 9 This is a schematic diagram of the outer support hook of an embodiment of the present invention;

[0048] Figure 10 This is a schematic diagram of the inner stent of the valve stent according to an embodiment of the present invention.

[0049] Please refer to Figures 1 to 7The valve prosthesis provided in this embodiment can be used for the replacement of mitral, tricuspid, aortic, or pulmonary valves, and is particularly suitable for mitral and tricuspid valves. The valve prosthesis includes a valve stent and a valve. The valve stent is a double-layer stent, including an outer stent 100, an inner stent 200, and at least one buffer portion 300. In this exemplary embodiment, the valve stent is suitable for a mitral valve prosthesis, and there is a gap between the outer stent 100 and the inner stent 200 of the double-layer stent, the size of which changes with the movement of the inner and outer stents. Preferably, the valve stent provided in this embodiment is a self-expanding mitral valve stent. In this embodiment, the connection between each strut of the outer stent 100 and the inner stent 200 is via the buffer portion 300. In other embodiments, the outer stent 100 is connected to at least one strut of the inner stent 200 via at least one buffer portion 300, while the others can be directly connected.

[0050] like Figure 1 As shown, the outer support 100 is, for example, the support located on the outer side of the double-layer support, serving to anchor and support the skirt during implantation. The outer support 100 preferably includes a flange 110, an outer support body 120, and barbs 130. The flange 110 is connected to one axial end of the support body 120, and the barbs 130 are located on the grid nodes of the outer support body 120 and extend towards the flange end. The inner support 200 preferably includes, for example, an inner support body 210. The outer support body 120 and the inner support body 210 are preferably, for example, an annular mesh. The outer support 100 and the inner support 200 are made of shape memory alloy, preferably nickel-titanium alloy; this embodiment does not limit the material of the outer support 100. The specific structure of the outer support 100 and the inner support 200 is described below. Figures 1 to 3As shown, the outer stent 100 is sleeved outside the inner stent 200 and connected to the inner stent 200 via the buffer portion 300. The buffer portion 300 is disposed between the outer stent 100 and the inner stent 200 to reduce the mutual force between the outer stent 100 and the inner stent 200, thereby achieving a buffering function. Preferably, the outer stent 100 and the inner stent 200 are connected along the outflow end of the valve stent via the buffer portion 300. In this embodiment, more preferably, the buffer portion 300 is disposed on the outer stent 100, for example, one end of the buffer portion 300 is integrally formed with the outer stent 100, and the other end of the buffer portion 300 is connected to the inner stent 200 via a lug, etc. Furthermore, the buffer portion 300 is disposed at the outflow end of the outer stent 100, which can achieve better mechanical performance while minimizing the impact on the inner stent 200. Of course, in other embodiments, the buffer portion 300 can also be disposed on the inner stent 200. For example, one end of the buffer portion 300 is integrally formed with the inner stent 200, and the other end of the buffer portion 300 is connected to the outer stent 100 via a lug. Alternatively, the buffer portion 300 can be a separate component, with one end of the buffer portion 300 connected to the outer stent 100 via a lug, and the other end of the buffer portion 300 connected to the inner stent 200 via a lug. More preferably, the extending direction A of the buffer portion 300 is angled to the axial direction B of the valve stent, thereby allowing the force of the outer stent 100 moving radially to be dispersed and absorbed by the buffer portion 300. More preferably, the angle α between the extending direction A of the buffer portion 300 and the axial direction B of the valve stent is set between 0 and 45°. Mechanical analysis shows that this allows the buffer portion 300 to better disperse and absorb the force of the outer stent 100 moving radially. Of course, the angle α between the extension direction A of the buffer portion 300 and the axial direction B of the valve stent can be set at 45°, and those skilled in the art can set it according to actual needs. In other embodiments, the extension direction A of the buffer portion 300 and the axial direction B of the valve stent can also be set greater than 45°, which can also realize the buffering function of the buffer portion 300. It is understood that the extension direction A of the buffer portion 300 can be the length direction of the overall structure of the buffer portion 300. The inner stent 200 is, for example, a stent located inside the double-layer stent, used to support the leaflets and skirt of the mitral valve prosthesis. The valve stent adopts a double-layer stent design, with the leaflets sutured to the inner stent 200. The area of ​​the leaflets when closed is smaller than that of a single-layer valve stent, so that the valve stent is subjected to less tensile force, which can effectively improve the fatigue resistance of the valve prosthesis. In the double-layer stent of the valve stent in this embodiment, since the outer stent 100 does not directly support the valve, the strength requirement for the outer stent 100 is weaker than that for a single-layer valve stent.Therefore, during left ventricular systole and diastole, under the same contractile force, the outer layer of the double-layer stent 100 will produce a greater deformation, which is conducive to the matching of the valve stent with the native tissue, thereby reducing the impact of the valve stent on ventricular contractile capacity, while also ensuring the stability of valve closure.

[0051] Preferably, the valve stent has an axial length along its own axis, and the projection of the buffer portion 300 along the axial direction B of the valve stent accounts for 20% to 30% of the length of the valve stent. For example, the projection of the buffer portion 300 along the axial direction B of the valve stent accounts for 20%, 25%, or 30% of the length of the valve stent. Specifically, for example, if the length of the valve stent is 100 mm, the projected length of the buffer portion 300 can be 20 mm, 25 mm, or 30 mm. For example, if the buffer portion 300 is set at 45° to the axial direction of the valve stent, and the projected length of the buffer portion 300 is limited to 30 mm, then the length of the buffer portion 300 can be 42.3 mm. This arrangement allows the buffer portion 300 to have better mechanical properties within the valve stent, thereby improving its buffering performance and reducing the mutual influence between the inner stent 200 and the outer stent 100. Of course, those skilled in the art can set the projected length of the valve stent according to actual needs. It should be understood that the numerical limits of 45° and 20% to 30% are not specific values. They can be values ​​that deviate slightly from the range of error, such as around 45°, around 20%, or around 30%.

[0052] Please refer to Figures 3 to 6The buffer portion 300 preferably includes at least one buffer structure 300a. The buffer structure 300a is preferably at least one of the following: a straight rod structure, an S-shaped bend structure, a Z-shaped bend structure, a square bend structure, or a trapezoidal bend structure. The buffer portion 300 can reduce the force from the outer support 100, resulting in less force on the inner support 200. This weakens or isolates the interaction force between the outer support 100 and the inner support 200, allowing the buffer portion 300 to significantly reduce or isolate the mutual force between them. Consequently, the buffer portion 300 can reduce or isolate the impact of the movement of the outer support 100 on the inner support 200, effectively reducing the influence of the movement of the outer support 100 on the opening and closing of the leaflets of the inner support 200. Thus, when the outer support 100 moves with the original valve annulus, the opening and closing of the leaflets of the inner support 200 are unaffected by the movement of the outer support 100, or minimally affected. In other embodiments, the buffer portion 300 is not limited to a curved structure, but can also be any other structure that can reduce the force from the outer support 100, such as a spiral structure or a conical structure. The spiral or conical structure is also used to absorb and disperse the force between the inner support 200 and the outer support 100.

[0053] Preferably, the buffer portion 300 includes a buffer structure 300a. The axis of the S-shaped curved structure of the buffer structure 300a extends in a wavy shape. The buffer structure 300a has a first width h1 in a direction perpendicular to its own axis. The distance between the crest and trough of the outer contour of the buffer structure 300a is a second width h2. The first width h1 is between one-quarter and one-half of the second width h2. In this exemplary embodiment, the buffer portion 300, for example, has an S-shaped curved structure 310. The first width h1 of the S-shaped curved structure 310 is one-quarter of the second width h2, thereby ensuring that the S-shaped curved structure 310 can absorb the force from the outer support 200. Of course, in other embodiments, the first width h1 of the buffer portion 300 can be one-third or one-half of the second width h2, etc. It is understood that the first width h1 can represent the width of the buffer portion 300 itself.

[0054] like Figure 3As shown, the buffer portion 300 further includes a connecting rod 300b. The buffer structure 300a is connected to one or more of the outer stent 100, the inner stent 200, and other buffer structures 300a via the connecting rod 300b. The distance between the crest and trough of the outer contour of the buffer structure 300a is a second width h2, which is not greater than the width of the connecting rod 300b along the circumferential direction of the valve stent. In this exemplary embodiment, the connecting rod 300b can extend along the axial direction B of the valve stent, thereby connecting the outer stent 100 with the buffer structure 300a, and connecting the inner stent 200 with the buffer structure 300a. Of course, the connecting rod 300b can also extend along the extension direction A of the buffer portion, as can be configured according to actual needs by those skilled in the art. In fact, when there are two or more buffer structures 300a, the connecting rod 300b can also be disposed between two buffer structures 300a to connect the two buffer structures 300a. The connecting rod 300b has a width along the circumference of the valve stent, the width being the width of the connecting rod 300b itself. The second width h2 is not greater than the width of the connecting rod 300b itself. This arrangement ensures the structural stability of the buffer portion 300 disposed between the outer stent 100 and the inner stent 200, preventing the second width h2 of the buffer portion 300 from being too wide or too narrow to provide a buffering effect.

[0055] Furthermore, the buffer section 300 includes an S-shaped curved structure 310. It is understood that the S-shaped curved structure 310 has a variable number of wavelets, and can be configured with multiple discontinuous or multiple continuous wavelets. Preferably, the S-shaped curved structure 310 includes a first straight segment 311, a first curved segment 312, a second straight segment 313, a second curved segment 314, and a third straight segment 315 connected in sequence. The first straight segment 311, the second straight segment 313, and the third straight segment 315 are straight, while the first curved segment 312 and the second curved segment 314 are curved. The curvature of the first curved segment 312 and the second curved segment 314 is the same, thereby ensuring that a single S-shaped curved structure 310 can uniformly absorb the applied force. Furthermore, the first straight segment 311, the second straight segment 313, and the third straight segment 315 have the same length along the circumferential direction of the valve stent in the buffer section 300, thereby ensuring the structural stability of the buffer section 300 and further ensuring its uniform absorption of the applied force.

[0056] Preferred, such as Figure 3As shown, the first straight segment 311, the second straight segment 313, and the third straight segment 315 are arranged parallel to each other, which is beneficial for the buffer portion 300 to better disperse strain when the outer stent 100 deforms. Furthermore, the first straight segment 311, the second straight segment 313, and the third straight segment 315 are perpendicular to the axial direction B of the valve stent, ensuring the position and orientation of the S-shaped bending structure on the outer stent 100, and guaranteeing that the buffer portion 300 better disperses strain and absorbs stress. In fact, the first straight segment 311, the second straight segment 313, and the third straight segment 315 can also be perpendicular to the extension direction A of the buffer portion.

[0057] Preferred, such as Figure 3 As shown, the first curved segment 312 and the second curved segment 314 are semi-circular ring structures. Understandably, when the first curved segment 312 bends, due to its own width, it forms two semi-circular structures. The semi-circle closer to the inside forms the inner circle, which has an inner diameter, and the semi-circle closer to the outside forms the outer circle, which also has an outer diameter. The inner and outer circles of the second curved segment 314 are similar to those of the first curved segment 312, and will not be described further here. The inner diameter of the semi-circular ring structure refers to the diameter of the inner circle closer to the inside, and this inner diameter is between one-quarter and one-half of the width of either the first curved segment 312 or the second curved segment 314. In this embodiment, the first width h1 of the first curved segment 312 and the second curved segment 314 is the same. The inner diameter of the semi-circular structure of the first curved segment 312 is preferably half of the first width h1 of the first curved segment 312, thereby controlling the distance between the first straight segment 311 and the second straight segment 313, and thus controlling the magnitude of the force dispersed by the buffer portion 300 from the outer support 100. Of course, in other embodiments, the inner diameter of the semi-circular structure of the first curved segment 312 is one-third, one-quarter, or other sizes of the first width h1 of the first curved segment. The smaller the inner diameter of the semi-circular structure, the greater the force dispersed by the buffer portion 300 from the outer support 100; the larger the inner diameter of the semi-circular structure, the smaller the force dispersed by the buffer portion 300 from the outer support 100. Those skilled in the art can set these dimensions according to actual conditions.

[0058] Preferably, the inner stent 200 has a valve connection portion, for example, the valve connection portion is where the inner stent 200 connects to the leaflet. When the outer stent 100 is connected to the inner stent 200 via a buffer portion 300, the valve connection portion of the inner stent 200 can be directly connected to the buffer portion 300, for example, the valve connection portion can also be indirectly connected to the buffer portion 300, for example, the valve connection portion can be connected to the buffer portion 300 via a connecting rod; or there can be one or several rows of mesh between the valve connection portion and the buffer portion 300. The buffer structure 300a of the buffer portion 300 connected to the valve connection portion has a first length along the extension direction A of the buffer portion, and the remaining buffer structures 300a of the buffer portion 300 have a second length along the extension direction A of the buffer portion, the first length being longer than the second length. This is because the valve connection is connected to the leaflet. When the leaflet opens and closes, it affects the force on the valve connection. The valve connection needs to withstand greater forces. In order to alleviate the transmission of forces at the valve connection of the inner stent 200, the buffer 300 needs to absorb and disperse more forces. Therefore, the buffer structure 300a connected to the valve connection needs to be longer so that the inner stent 200 and the outer stent 100 are as independent as possible from each other and are not affected by forces.

[0059] like Figures 3 to 6 As shown, preferably, the valve stent includes at least one of the buffer portions 300, the buffer portion 300 having at least one buffer structure 300a, the buffer structure 300a including at least one of an S-shaped bend structure, a Z-shaped bend structure, a square bend structure, or a trapezoidal bend structure. In this embodiment, as... Figure 2 and Figure 3 The valve stent includes several buffer portions 300, each buffer portion 300 having one, two, or more buffer structures 300a, with adjacent buffer structures 300a connected by a connecting rod 300b. The buffer structure 300a is preferably, for example, an S-shaped bend structure 310, which better disperses stress. The length of the buffer structure 300a along the extending direction A of the buffer portion can be set according to actual needs, for example... Figure 3The two buffer structures 300a, one on the right and one in the middle, are shown in the diagram. The lengths of the two buffer structures 300a may be different. In an exemplary embodiment, the lengths of the buffer structures 300a in each buffer section 300 are the same, thereby ensuring that the buffer structures 300a at the connection between the outer support 100 and the inner support 200 can uniformly buffer the force when the outer support 100 moves. Furthermore, the buffer structures 300a of all the buffer sections 300 of the outer support 100 are of the same type of bending structure, for example, all of them are S-shaped bending structures 310. More preferably, the number of S-shaped bending structures 310 is the same, thereby enabling the buffer structures 300a to uniformly buffer the force. In other embodiments, the buffer structures 300a can also be combinations of different bending structures. For example, on one buffer section 300, the buffer structure 300a can be a combination of an S-shaped bending structure 310 and a Z-shaped bending structure 320, or it can be a Z-shaped bending structure 320 or a square bending structure 330, etc. Alternatively, each of the buffer portions 300 may be provided with different buffer structures 300a, for example, one buffer portion 300 may be provided with an S-shaped bending structure 310 and another with a square bending structure 330; or, one buffer portion 300 may be provided with a Z-shaped bending structure 320 and another with a trapezoidal bending structure 340, etc.

[0060] Preferably, the valve stent further includes stent loops 400, and the buffer portion 300 is connected to the inner stent via the stent loops 400. The stent loops 400 are used to mate with the valve prosthesis and the delivery system for transporting the valve prosthesis. The stent loops 400 and the groove shape of the delivery system are matched to form a connection, ensuring that the relative position of the valve prosthesis and the delivery system remains unchanged during the loading of the valve prosthesis into the delivery system, the release of the valve prosthesis from the delivery system, and its transport within the body. The number and position of the stent loops 400 can be determined according to actual needs. In this embodiment, the stent loops 400 are configured to mate with the groove of the delivery system and are connected to the buffer portion and the inner stent. The bracket hook 400 includes, for example, an inner bracket hook 410 and an outer bracket hook 420. The outer bracket hook 420 is connected to the buffer portion 300, the inner bracket hook 410 is connected to the inner bracket 200, and the outer bracket hook 420 is connected to the inner bracket hook 410, thereby connecting the buffer portion 300 to the inner bracket 200. Alternatively, in other embodiments, the buffer portion 300 may be directly connected to the inner bracket.

[0061] In this exemplary embodiment, as Figure 1 and Figure 3As shown, the outflow end of the outer support 100 has a mesh structure, which is arranged around the circumference of the outer support 100. The mesh structure is preferably a rhomboid mesh structure. One connecting rod of each buffer section 300 is preferably connected to a vertex of the rhomboid mesh structure. One end of one buffer structure of the buffer section 300 is connected to one connecting rod. This buffer structure is preferably an S-shaped curved structure as described above. The other end of one buffer structure is connected to one end of another connecting rod, and the other end of the other connecting rod is connected to an outer support lug 420. The outer support lug 420 is connected to an inner support lug 410, which is connected to the inner support 200. This arrangement allows the outer support 100 and the inner support 200 to be connected through the buffer section 300. The buffer structure 300a of the buffer section 300 absorbs or buffers forces, thereby buffering the forces between the outer support 100 and the inner support 200. Of course, the mesh structure of the outer support 100 can also be a triangular or other polygonal structure. The number of buffer parts 300, the number of connecting rods 300b or buffer structures 300a in the buffer part 300, the specific structure of the inner support hanging ear 410 and the outer support hanging ear 420 can be set according to the actual situation. Please refer to the relevant description in the text for details, which will not be repeated here.

[0062] The following will describe in detail the specific structures of the outer support 100, outer support lug 420, inner support 200 and inner support lug 410 mentioned above in this embodiment.

[0063] The outer support 100 also includes a flange 110, an outer support body 120, and barbs 130.

[0064] like Figure 2 As shown, the diameter of the flange 110 is slightly larger than the diameter of the outer support body 120. The maximum diameter at the edge of the flange 110 ranges from 30 to 100 mm. Axially, the end where the flange 110 is located is the proximal end, and the end furthest from the flange 110 is the distal end. Figure 2As shown, the flange 110 can be a V-shaped structure or a diamond-shaped mesh structure, with the diamond-shaped mesh structure referencing the design of the outer support body 120. The flange 110 can be manufactured in various ways. For example, the flange 110 can be integrally formed with the outer support body 120 using cutting technology: the outlines of the flange 110 and the outer support body 120 are cut from a metal tube using laser or other cutting methods, and then the mitral valve stent is expanded and shaped into the designed structure through a heat treatment process. Alternatively, the flange 110 and the outer support body 120 can be formed separately using cutting technology: the outline of the flange 110 is cut from a metal tube using laser or other cutting methods, and then the flange 110 is expanded and shaped into the designed structure through a heat treatment process. Finally, the flange 110 is connected to the outer support body 120 by welding, riveting, or using skirts, sutures, or pericardial materials. Of course, the flange 110 can also be formed using other methods, which are not limited in this embodiment.

[0065] Please refer to Figure 2 , Figure 7 and Figure 8 The outer support body 120 has a slightly smaller diameter than the flange 110. The diameter of the end where the outer support body 120 connects to the flange 110 ranges from 20-90 mm, and the diameter of the far end also ranges from 20-90 mm. The diameters at both ends are independent and there is no absolute size relationship between them. For example... Figure 7 and Figure 8 As shown, the outer support body 120 structure can be a rhomboid mesh structure, or it can be designed as a near-rhomboid mesh structure or a hexagonal structure. For example... Figure 7 In the approximate rhomboid structure, the lengths of the upper side rod and the side rods are independent; the upper side rod may be longer or shorter than the lower side rod. The outer support body 120 can be manufactured in various ways. For example, the outline of the outer support body 120 can be cut from a metal tube using laser cutting methods, and then the outer support body 120 can be expanded and shaped into the designed structure through a heat treatment process. Another example is that the outer support body 120 can be directly woven from metal wire. Yet another example is that the outer support body 120 can be printed using 3D printing technology with metal as the material. Of course, the outer support body 120 can also be formed using other methods, which are not limited in this embodiment.

[0066] Preferably, the buffer part 300 can be integrally formed with the outer support 100 using cutting technology: the outline of the flange 110 and the outer support body 120 are cut from the metal tube using laser or other cutting methods, and then the mitral valve stent is expanded and shaped into the designed structure through a heat treatment shaping process.

[0067] like Figure 2 and Figure 7As shown, the barbs 130 are located on the grid nodes of the outer support body 120 and are evenly distributed circumferentially. The barbs 130 and the outer support body 120 can have a certain angle, ranging from 0° to 90°. The barbs 130 can be manufactured in various different ways. For example, the barbs 130 can be integrally formed with the outer support body 120 using cutting technology.

[0068] like Figures 1 to 3 as well as Figure 9 As shown, the outer support hook 420 is located at the lower end of the buffer portion 300. The outer support hook 420 can be annular, T-shaped, or even a square ring, elliptical ring, or hook-shaped, etc. Those skilled in the art can design the structure of the outer support hook 420 according to actual needs, and this embodiment does not impose any limitations. The outer support hooks 420 are circumferentially distributed, and one or more hooks may exist on the same row. The outer support hooks 420 can be integrally formed with the outer support body 120 and the buffer portion 300 using cutting technology.

[0069] like Figure 10 As shown, the inner support 200 includes an inner support body 210, and the inner support lug 410 is connected to the inner support body 210.

[0070] like Figure 10 As shown, the maximum diameter of the inner stent body 210 is smaller than the minimum diameter of the outer stent 100. The proximal end of the inner stent body 210 is the inflow end of the membrane stent, and the distal end is the outflow end of the valve stent. Similar to the outer stent body 120, the proximal end of the inner stent body 210 can be a rhomboid mesh structure, or it can be designed as an approximately rhomboid mesh structure or a hexagonal structure. The upper and lower side rods are independent, and the upper side rod may be longer or shorter than the lower side rod. The distal structure of the inner stent body 210 is a combination of straight rods and wave rods. The inner stent body 210 can be manufactured in various different ways. For example, the outline of the inner stent body 210 can be cut from a metal tube using laser cutting methods, and then the inner stent body 210 can be expanded and shaped into the designed structure through a heat treatment process. Another example is that the inner stent body 210 can be directly woven from metal wire to form the designed structure. For example, the inner support body 210 can be designed using 3D printing technology with metal as the material. Of course, the inner support body 210 can also be formed using other methods, which are not limited in this embodiment.

[0071] The inner support lug 410 and the outer support lug 420 are one-to-one corresponding and then connected together. The connection method can be welding, riveting, or adding other connecting parts, such as adding a ring. Other connection methods are also possible, and this embodiment does not limit them. The connection can be such that the inner support lug 410 and the outer support lug 420 are tightly fitted together, or it can have a certain gap, allowing relative movement of 0-1mm. The inner support lug 410 and the outer support lug 420 are the same in size, number, shape, position, and manufacturing method.

[0072] This embodiment also provides a valve prosthesis, which includes: a valve stent, leaflets, and a skirt as described above, wherein the leaflets and the skirt are respectively disposed on the valve stent. The beneficial effects of the valve stent provided by the valve prosthesis are not elaborated here. The structure and principle of the leaflets and the skirt can be referred to in the prior art, and will not be described in detail in this embodiment. The structure and principle of other components of the valve prosthesis can be referred to in the prior art, and will not be described in detail in this embodiment.

[0073] In summary, in the valve stent and valve prosthesis provided in this embodiment of the invention, the valve stent includes an outer stent, an inner stent, and at least one buffer portion. The outer stent is sleeved over the inner stent and connected to the inner stent via the buffer portion. The buffer portion effectively reduces the impact of deformation of the outer stent on the opening and closing of the leaflets on the inner stent, thereby significantly reducing or isolating the mutual stress between the outer and inner stents. Furthermore, the valve stent employs a double-layer stent design, which effectively enhances the fatigue resistance of the valve prosthesis, allows for a closer fit between the valve prosthesis and the native tissue, reduces the impact of the valve stent on ventricular contractility, and ensures stable valve closure.

[0074] Furthermore, it should be understood that although the present invention has been disclosed above with reference to preferred embodiments, these embodiments are not intended to limit the present invention. For any person skilled in the art, many possible variations and modifications can be made to the technical solutions of the present invention based on the disclosed technical content, or equivalent embodiments can be modified accordingly, without departing from the scope of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention, without departing from the content of the present invention, shall still fall within the scope of protection of the present invention.

Claims

1. A valve stent, characterized in that, include: An outer support, an inner support, and at least one buffer section; The outer support is sleeved outside the inner support and is connected to the inner support through the buffer part, which is used to reduce the mutual force between the outer support and the inner support. The buffer portion is disposed on the outer support, and the buffer portion includes at least one buffer structure, which includes at least one of a straight rod structure, an S-shaped bending structure, a Z-shaped bending structure, a square bending structure, or a trapezoidal bending structure. The extension direction of the buffer portion is set at an angle to the axial direction of the valve stent.

2. The valve stent according to claim 1, characterized in that, The buffer section further includes a connecting rod, and the buffer structure is connected to one or more of the outer support, the inner support, and other buffer structures via the connecting rod; the distance between the crests and troughs of the outer contour of the buffer structure is a second width, and the second width is not greater than the width of the connecting rod along the circumference of the valve support.

3. The valve stent according to claim 1, characterized in that, The axis of the S-shaped curved structure extends in a wave shape. The buffer structure has a first width in the direction perpendicular to its own axis. The distance between the crest and trough of the outer contour of the buffer structure is a second width. The first width is between one-quarter and one-half of the second width.

4. The valve stent according to claim 1, characterized in that, The S-shaped curved structure includes a first straight segment, a first curved segment, a second straight segment, a second curved segment, and a third straight segment connected in sequence. The first straight segment, the second straight segment, and the third straight segment are straight, and the first curved segment and the second curved segment are curved. The curvature of the first curved segment and the second curved segment are the same.

5. The valve stent according to claim 4, characterized in that, The first straight segment, the second straight segment, and the third straight segment are arranged parallel to each other, and the first straight segment, the second straight segment, and the third straight segment are perpendicular to the axis of the valve stent.

6. The valve stent according to claim 5, characterized in that, The first curved segment and the second curved segment are semi-circular ring structures. The buffer structure has a first width in the direction perpendicular to its own axis. The inner diameter of the semi-circular ring structure is between one-quarter and one-half of the first width.

7. The valve stent according to claim 1, characterized in that, The inner stent has a valve connection portion, and the buffer structure of the buffer portion connected to the valve connection portion has a first length along the extension direction of the buffer portion, and the remaining buffer structures of the buffer portion have a second length along the extension direction of the buffer portion, wherein the first length is longer than the second length.

8. The valve stent according to claim 1, characterized in that, The valve stent has a valve stent length along its own axial direction, and the length of the buffer portion projected along the axial direction of the valve stent accounts for 20% to 30% of the length of the valve stent.

9. The valve stent according to claim 1, characterized in that, The valve stent also includes a stent lug, and the buffer portion is connected to the inner stent via the stent lug.

10. The valve stent according to claim 1, characterized in that, The outer stent and the inner stent are connected along the outflow end of the valve stent through the buffer section.

11. The valve stent according to claim 1, characterized in that, The outer support includes a flange, an outer support body, and barbs. The flange is connected to one axial end of the support body, and the barbs are located on the grid nodes of the outer support body and extend toward the flange end.

12. A valve prosthesis, characterized in that, include: The valve stent, leaflet, and skirt according to any one of claims 1-11; wherein the leaflet and the skirt are respectively disposed on the valve stent.

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