Prosthetic heart valve

Abstract

The application provides an artificial heart valve, which comprises a support and an artificial valve leaflet, the artificial valve leaflet is connected with the support, the support is divided into an inflow tract and an outflow tract in the axial direction, the outflow tract has a plurality of support sewing rods which are concave in the direction of the inflow tract and are arranged in an arc shape, and a blank area is formed on the side of the support sewing rods away from the inflow tract, the plurality of support sewing rods are sequentially arranged in the circumferential direction of the support, the two ends of the adjacent two support sewing rods are connected through a support window, the artificial valve leaflet comprises a valve leaflet free edge part, a valve leaflet commissure part and a valve leaflet fixed edge part, the two ends of the valve leaflet free edge part and the valve leaflet fixed edge part are connected through the valve leaflet commissure part, the valve leaflet fixed edge part is sewn and fixed with the support sewing rod, and the valve leaflet commissure part is sewn and fixed with the support window. The application can make the blood flow fully flow during the opening and closing of the artificial valve leaflet, avoid the formation of a dead zone of blood flow stagnation, and reduce thrombosis.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and in particular to an artificial heart valve that can reduce blood clots. Background Technology

[0002] The heart has four chambers: the left atrium and left ventricle are located on the left side of the heart, and the right atrium and right ventricle are located on the right side. The atria and ventricles form the ventricular inflow tract, the left ventricle and aorta form the left ventricular outflow tract, and the right ventricle and pulmonary artery form the right ventricular outflow tract. At the ventricular inflow tract and left ventricular outflow tract, there are valves that function as one-way valves, ensuring the normal flow of blood within the heart chambers. When these valves malfunction, cardiac hemodynamics change, and cardiac function becomes abnormal; this is called valvular heart disease.

[0003] With socioeconomic development and population aging, the incidence of valvular heart disease has increased significantly. Studies show that the incidence rate in people over 75 years of age is as high as 13.3%. Currently, traditional surgical treatment remains the first-line treatment for patients with severe valvular disease. However, for elderly patients, those with multiple organ diseases, those with a history of open-heart surgery, and those with poor cardiac function, traditional surgery carries high risks and mortality rates, and some patients may not even have the opportunity to undergo surgery. Transcatheter valve replacement / repair has received widespread attention due to its advantages such as not requiring open-heart surgery, minimal trauma, and rapid patient recovery.

[0004] Valvular thrombosis remains a pressing problem. Thrombi are classified into white thrombi and red thrombi. White thrombi occur in areas of rapid blood flow and are composed of numerous platelet deposits and a small amount of fibrin; they are commonly found on the inflow side of the valve. Red thrombi are dark red and occur in areas of stagnant blood flow in the valve, commonly found on the outflow side. However, current technologies have not effectively solved the problem of valvular thrombosis, thus necessitating further improvements to artificial heart valves.

[0005] It should be noted that the information disclosed in the background section of this application is intended only to enhance the understanding of the general background of this application, and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] To address the problems existing in the prior art, the present invention provides an artificial heart valve that can reduce the area of ​​blood stagnation, lower the risk of thrombosis, and improve the anticoagulant capacity of the artificial heart valve.

[0007] To achieve the above objectives, the present invention provides an artificial heart valve, comprising a stent and an artificial leaflet, wherein the artificial leaflet is connected to the stent, the stent being axially divided into an inflow tract and an outflow tract, the outflow tract having multiple stent suture rods concave inward toward the inflow tract and forming a blank area on the side of the stent suture rods away from the inflow tract, the multiple stent suture rods being arranged sequentially in the circumferential direction of the stent, the ends of adjacent stent suture rods being connected through a stent window, the artificial leaflet comprising a leaflet free edge, a leaflet merging part, and a leaflet fixing edge, the ends of the leaflet free edge and the leaflet fixing edge being connected through the leaflet merging part, the leaflet fixing edge being sutured and fixed to the stent suture rods, and the leaflet merging part being sutured and fixed to the stent window.

[0008] In one embodiment, the leaflet fixing edge has a leaflet starting portion located at the junction of the leaflet connecting portion and the leaflet fixing edge. The leaflet fixing edge also has a first tangent passing through the leaflet starting portion. The first tangent forms an angle at the starting point with the direction of the outflow channel pointing to the inflow channel. The angle at the starting point is configured to increase the opening area of ​​the artificial leaflet.

[0009] In one embodiment, the included angle at the starting point is 0°-15°.

[0010] In one embodiment, the included angle at the starting point is 5°-10°.

[0011] In one embodiment, the leaflet fixing edge has a leaflet bottom, which is the position of the leaflet fixing edge closest to the inflow channel. The leaflet fixing edge also has a second tangent passing through the leaflet bottom, which forms a bottom upper angle with the direction of the inflow channel pointing to the outflow channel. The bottom upper angle is configured to flatten the leaflet bottom.

[0012] In one embodiment, the included angle at the bottom is 75°-90°.

[0013] In one embodiment, the included angle at the bottom is 80°-85°.

[0014] In one embodiment, the surfaces of the artificial leaflet facing the inflow channel and the outflow channel are both smooth surfaces.

[0015] In one embodiment, the artificial leaflet is composed of two parts joined together, and / or the artificial leaflet is made of a double pericardium with the pericardial connective tissue layers of the double pericardium facing each other.

[0016] In one embodiment, the artificial leaflet is sutured and fixed to the support by wrapping it around the support. The leaflet fusion portion is sutured and fixed by passing through the support window from the outside of the support to the inside of the support. The leaflet fixing edge is wrapped around the support suture rod from the outside of the support and then sutured and fixed to the support suture rod.

[0017] In one embodiment, the leaflet fusion portion passes through the support window from the outside of the support to the inside of the support and is then sutured and fixed to itself, and / or, the leaflet fixing edge is wrapped by the outside of the support over at least a portion of the support suture rod and then sutured and fixed to the support suture rod.

[0018] In one embodiment, the blank area is either an open area or a closed area.

[0019] In one embodiment, the shape of the support window matches the shape of the leaflet junction.

[0020] In one embodiment, the bracket window is rectangular, square, or rhomboid in shape, with a width of 0.1mm-2mm in the circumferential direction and a length of 1mm-10mm in the axial direction.

[0021] The artificial heart valve provided by this invention includes a stent and an artificial leaflet. The artificial leaflet is connected to the stent. The stent is axially divided into an inflow tract and an outflow tract. The outflow tract has multiple stent suture rods that are concave inward towards the inflow tract, and a blank area is formed on the side of the stent suture rods away from the inflow tract. The multiple stent suture rods are arranged sequentially in the circumferential direction of the stent. The two ends of adjacent stent suture rods are connected through a stent window. The artificial leaflet includes a free edge, a leaflet fusion portion, and a fixed edge. The two ends of the free edge and the fixed edge are connected through the leaflet fusion portion. The fixed edge is sutured to the stent suture rods, and the leaflet fusion portion is sutured to the stent window. This design allows for sufficient blood flow during the opening and closing of the artificial valve, avoiding the formation of dead zones where blood flow stagnates, thereby reducing thrombus formation, especially the risk of red blood clots. Furthermore, by improving the included angle at the starting point of the artificial valve leaflet, the present invention increases the opening area of ​​the artificial valve leaflet, which can further reduce the risk of blood flow stagnation and the risk of red blood clot formation. Furthermore, by improving the included angle at the bottom of the artificial valve leaflet, the present invention makes the bottom of the leaflet flat, which can also further reduce the risk of blood flow stagnation and the risk of red blood clot formation. Furthermore, by improving the material or structure of the artificial valve leaflet, making both the inflow and outflow surfaces smooth, the risk of white blood clots formed due to faster blood flow in the inflow tract can be reduced. Attached Figure Description

[0022] 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:

[0023] Figure 1 This is a schematic diagram of the overall structure of the artificial heart valve provided in an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the main structure of the support provided in an embodiment of the present invention. The arrows in the diagram indicate the direction from the inflow channel to the outflow channel.

[0025] Figure 3 This is a side view of the support structure provided in an embodiment of the present invention;

[0026] Figure 4 This diagram illustrates the principle of white blood cell formation. The arrows in the diagram indicate the direction of blood flow, that is, blood flows from the inflow channel to the outflow channel.

[0027] Figure 5 This diagram illustrates the principle of red blood clot formation. The arrows in the diagram indicate the direction of blood flow, that is, blood flows from the outflow tract to the inflow tract.

[0028] Figure 6 This is a schematic diagram of the structure of an artificial valve leaflet with a double pericardium provided in an embodiment of the present invention;

[0029] Figure 7 This is a schematic diagram of the structure of an artificial leaflet provided in an embodiment of the present invention;

[0030] Figure 8a This is a schematic diagram illustrating the structural principle of the invention regarding the improvement of the included angle at the starting point;

[0031] Figure 8b for Figure 8a A magnified view of position D in the middle;

[0032] Figure 8c This is a comparison diagram showing the effect of the improved angle at the starting point before and after the improvement in this invention;

[0033] Figure 9 This is a schematic diagram illustrating the improved bottom upper angle of the present invention.

[0034] Figure 10 and Figure 11 This is a diagram illustrating the suturing principle of the artificial leaflet in the comparative embodiment;

[0035] Figure 12 This is a schematic diagram of the main view of the artificial valve leaflet sutured using an external wrapping method, provided in an embodiment of the present invention.

[0036] Figure 13This is a side view diagram of an artificial valve leaflet sutured using an external wrapping method, provided in an embodiment of the present invention.

[0037] Figure 14 This is a schematic diagram of the structure of the artificial valve leaflet and the stent suture rod sutured in a fully enclosed manner according to an embodiment of the present invention;

[0038] Figure 15 This is a schematic diagram of the structure of the artificial valve leaflet and the stent suture rod sutured using a local wrapping method, provided in an embodiment of the present invention;

[0039] Figure 16 This is a schematic diagram of a structure for suturing artificial leaflets and stent windows using a fully enclosed method, provided as an embodiment of the present invention.

[0040] The annotations in the attached figures are explained as follows:

[0041] 100 - Artificial heart valve; 110 - Stent; A - Inflow tract; B - Outflow tract; C - Blank area; 110a - Central axis of the stent; 110b - Medial side of the stent; 110c - Lateral side of the stent; 111 - Stent suture rod; 112 - Stent mesh; 113 - Stent window; 120 - Skirt; 130 - Artificial leaflet; 130a - Double pericardium; 131 - Leaflet commissure; 132 - Leaflet fixed edge; 1321 - Leaflet origin; 1322 - Leaflet base; 133 - Leaflet free edge; 140 - Suture line; L1 - Dashed line; L2 - Solid line; θ1 - Angle at the starting point of the comparative embodiment; θ2 - Improved angle at the starting point; α1 - Angle at the bottom of the comparative embodiment; α2 - Improved angle at the bottom; 10 - White thrombus; 20 - Red thrombus; 30 - Dead zone. Detailed Implementation

[0042] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] In the description of this invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0044] 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. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0045] As used in this article, "circumferential" refers to the direction around the central axis of the stent, and "axial" refers to the direction parallel to the central axis of the stent. The "inflow tract" refers to the portion of the blood flow into the valve during artificial heart valve surgery, and the "outflow tract" refers to the portion of the blood flow out of the valve during artificial heart valve surgery.

[0046] The core of this application is to provide an artificial heart valve to better solve the problem of valve thrombosis.

[0047] The following description refers to the accompanying drawings. Unless otherwise specified, the following embodiments and features can complement or combine with each other.

[0048] like Figure 1 As shown, this embodiment of the invention provides an artificial heart valve 100, which can be used to replace any type of native valve, such as the mitral valve, tricuspid valve, aortic valve, or pulmonary valve. The artificial heart valve 100 includes a stent 110, a skirt 120, and an artificial leaflet 130.

[0049] Artificial leaflet 130 is attached to stent 110. Stent 110 provides several functions for artificial heart valve 100, including serving as the main structure of the valve, supporting the internal artificial leaflet 130, and connecting to the delivery system (hook or fixation hook), etc.

[0050] The stent 110 is axially divided into an inflow tract A and an outflow tract B. To prevent paravalvular leakage, a skirt 120 is sutured to the inflow tract A of the stent 110. The skirt 120 can be single-layered or double-layered. A double-layered skirt means that the inner side (corresponding to the inner side 110b) and the outer side (corresponding to the outer side 110c) of the inflow tract A of the stent 110 are both sutured with skirts 120, with an inner skirt on the inner side and an outer skirt on the outer side. A single-layered skirt means that the inner side of the inflow tract A has an inner skirt. The inner skirt is fixed to the inner side of the inflow tract A and is fixedly connected to the artificial leaflet 130. Preferably, the inner side of the inflow tract A has an inner skirt, and the outer skirt is sutured at the contact point with the original valve annulus tissue to effectively prevent paravalvular leakage. The outer skirt can completely wrap around the circumference of the stent 110 at the inflow tract A of the stent 110, which can effectively prevent paravalvular leakage.

[0051] The stent 110, skirt 120, and artificial leaflet 130 are connected to each other by sutures 140. The skirt 120 can be made of knitted, woven, or braided polyester fabric, such as PTFE or ePTFE. The sutures 140 are conventional medical sutures, such as those made of PTFE, ePTFE, or PE.

[0052] The stent 110 can be understood as a mesh-like stent structure, which typically has a contracted state for delivery and an expanded state for deployment. The stent 110 can be woven or cut. The stent 110 can be made of materials such as nickel-titanium, titanium alloy, cobalt-chromium alloy, MP35n, 316 stainless steel, or other biocompatible metal frames or laser-cut solid metal tubes known to those skilled in the art, preferably nickel-titanium alloy. The stent 110 can also be made of elastically or plastically deformable materials, such as expandable materials found in balloons.

[0053] like Figure 2 and Figure 3 As shown, the outflow channel B of the stent 110 has stent suture rods 111 that are concave inward toward the inflow channel A in an arc shape (including a near-arc shape), and a blank area C is formed on the side of the stent suture rods 111 away from the inflow channel A. The number of stent suture rods 111 can be set according to the application scenario, such as two or three stent suture rods 111, and the number of stent suture rods 111 is consistent with the number of artificial leaflets 130. All stent suture rods 111 are arranged sequentially in the circumferential direction of the stent 110, and the two ends of adjacent stent suture rods 111 are connected through stent windows 113. That is, one end of stent suture rod 111 is connected to one end of another adjacent stent suture rod 111 through stent window 113, and the other end of stent suture rod 111 is connected to the other end of another adjacent stent suture rod 111 through another stent window 113. The stent suture rods 111 are continuous lines, distinct from the stent rods formed by the stent grid 112. The bracket window 113 can be understood as a through hole, which penetrates the inner and outer surfaces of the bracket 110.

[0054] like Figure 7As shown, the artificial leaflet 130 is basically symmetrical overall, and includes a leaflet connecting portion 131, a leaflet fixed edge portion 132, and a leaflet free edge portion 133. Both ends of the leaflet free edge portion 133 and the leaflet fixed edge portion 132 are connected by the leaflet connecting portion 131. That is, one end of the leaflet free edge portion 133 is connected to one end of the leaflet fixed edge portion 132 through the leaflet connecting portion 131, and the other end of the leaflet free edge portion 133 is connected to the other end of the leaflet fixed edge portion 132 through another leaflet connecting portion 131. The leaflet fixed edge portion 132 is basically arc-shaped (including quasi-arc-shaped). Multiple artificial leaflets 130 are always in contact with each other at the connecting portion 131. The shape of the free edge 133 of the leaflet is not limited. For example, the free edge 133 of the leaflet can be an upward arc protruding away from the fixed edge 132 of the leaflet, or a downward arc protruding towards the fixed edge 132 of the leaflet, or a straight shape, preferably an upward arc. The fixed edge 132 of the leaflet is sewn to the support suture rod 111. The fixed edge 132 of each artificial leaflet 130 is sewn to one support suture rod 111, while the leaflet connecting part 131 is sewn to the support window 113.

[0055] After implantation into the heart, the artificial heart valve 100 of the present invention has a blank area C in the direction of the outflow tract B because the stent 110 is arranged in the stent suture rod 111. This allows blood flow to be sufficient during the opening and closing of the artificial valve leaflet 130, avoiding the formation of a dead zone 30 where blood flow stagnates, thereby reducing thrombus formation, especially reducing the risk of red thrombus 20 formation.

[0056] In the illustrated embodiment, the blank area C is an open area (non-closed space). In this case, the side of the stent suture rod 111 away from the inflow channel A is the blank area C, and no stent rod is provided (i.e., no stent mesh 112 is formed). However, in other embodiments, the open blank area C can be replaced with a non-open area (i.e., closed space). In this case, the stent suture rod 111 is provided at an appropriate position on the side away from the inflow channel A (i.e., a stent mesh 112 is formed), and the stent rod at the outflow channel B should be as far away from the stent suture rod 111 as possible.

[0057] The stent suture rod 111 can be obtained by laser cutting. The side of the stent suture rod 111 closest to the inflow channel A is the grid area of ​​the inflow channel A. The stent grid 112 in the grid area can be any suitable shape, such as square, rectangle, rhombus, etc., and the present invention is not limited in this respect.

[0058] The shape of the stent window 113 preferably matches the shape of the leaflet fusion portion 131 to ensure the connection stability and fatigue life of the artificial heart valve. The leaflet fusion portion 131 preferably adopts a shape that improves valve fatigue life and connection stability, such as a rectangle, square, or rhombus, preferably a rectangle. In the illustrated embodiment, the stent window 113 is rectangular. The same stent window 113 is simultaneously connected to the leaflet fusion portions 131 of two adjacent artificial leaflets 130. The circumferential width of the stent window 113 on the stent 110 is set according to the thickness of the artificial leaflet 130. Understandably, the width of the stent window 113 is twice the thickness of the two adjacent artificial leaflets 130. For example, the width of the stent window 113 is 0.1mm-2mm, more preferably 0.4mm-1mm, to ensure the tight connection of the artificial leaflets 130 at the stent window 113, achieving a stable connection. The length of the stent window 113 in the axial direction of the stent 110 is mainly set according to the diameter of the stent 110. The length of the stent window 113 is the height of the leaflet fusion portion 131. For example, the length of the stent window 113 is 1mm-10mm, and more preferably 3mm-6mm. Such a length is beneficial to improving the fatigue life of the artificial heart valve.

[0059] The artificial leaflet 130 dynamically switches between open and closed states. In the closed state, the free edges 133 of the leaflet 130 are tightly closed or joined in a sealing manner. In the open state, the free edges 133 of the leaflet 130 are opened apart. The artificial leaflet 130 can be made from biological tissue, such as chemically stable tissue from animal (e.g., pig) heart valves, or pericardial tissue from animals such as cattle (bovine pericardium), sheep (sheep pericardium), pigs (pig pericardium), or horses (equine pericardium), with bovine pericardial tissue being preferred. The artificial leaflet 130 can also be made from submucosal tissue of the small intestine. It should be understood that the pericardium is mainly composed of a serosal layer, a fibrous layer, and an extrapericardial connective tissue layer; the serosal layer is relatively smooth, called the "smooth surface," and generally faces the outflow tract B; the extrapericardial connective tissue layer is relatively rough, called the "rough surface," and faces the inflow tract A, i.e., a rough surface. Of course, those skilled in the art should understand that the smooth surface referred to in this invention means a surface with a very low coefficient of friction, which is relative to a rough surface, but should not be understood as having absolutely no friction, but rather being generally smooth. The smoothness of the surface of the artificial leaflet 130 can be defined by its roughness; the larger the Ra value of the roughness, the rougher the surface, while the smooth surface described herein is a surface with a small Ra value of roughness.

[0060] Figure 4 The artificial leaflet 130 is shown in its open state. Figure 4As shown, in the open state, blood flows along the inflow channel A of the stent 110 towards the outflow channel B (the arrows in the figure indicate the direction of blood flow). The blood flow velocity at the inflow channel A is relatively fast, which can easily lead to platelet activation, followed by deposition on the rough surface, forming a white thrombus 10. In existing methods, the surface fibers are usually trimmed to reduce surface roughness and lower the risk of white thrombus formation, but this cannot make it completely smooth, and the trimming process can easily damage the valve leaflets, reducing valve life.

[0061] To reduce the formation of leukocytosis 10, both the surface of the artificial valve leaflet 130 facing the outflow tract B and the surface facing the inflow tract A are designed to be smooth. The smooth surface is not limited to the material used to prepare the artificial valve leaflet 130; it can also be a coating, preferably a coating with a low coefficient of friction. In this embodiment, the artificial valve leaflet 130 is composed of two parts joined together, ensuring that both the surface facing the outflow tract B and the surface facing the inflow tract A are smooth.

[0062] like Figure 6 As shown, in some embodiments, the artificial valve leaflet 130 uses a double-layered pericardium 130a, with the rough surfaces (external connective tissue layer) of the double-layered pericardium 130a joined together to form a complete pericardium, achieving smooth surfaces on both sides of the pericardium, thereby reducing the risk of leukothrombus formation. Although the artificial valve leaflet 130 made of pericardium is mentioned, those skilled in the art will understand that other materials can also be used to prepare the artificial valve leaflet 130, as described above. In any case, the surface of the artificial valve leaflet 130 facing the inflow tract A should be as smooth as possible to reduce the risk of leukothrombus formation due to the rapid blood flow in the inflow tract A. The double-layered pericardium 130a can be sutured together or bonded together. Figure 6 As shown, the area between the dashed line L1 and the solid line L2 forms the suture or adhesion zone for the double pericardium 130a. When the double pericardium 131 is bonded together, tissue adhesives can be used, including but not limited to 3A-TCMBAs, fibrin glue, WAB bio-adhesives, cyanoacrylate, gelatin / resorcinol complex, fibrinogen, oxidized regenerated fibrous material, succinyl phthalate, etc.

[0063] Figure 5 The artificial leaflet 130 is shown in its closed state. Figure 5 As shown, in the closed state, blood flows back in the opposite direction (i.e., from the outflow tract B to the inflow tract A along the stent 110), easily forming a backflow vortex at the bottom 1322 of the artificial valve leaflet 130, resulting in a dead zone 30 where blood flow stagnates, subsequently forming a red thrombus 20. At this time, the artificial valve leaflet 130 is prone to forming a dead zone due to the obstruction of the stent strut on the outer side of the leaflet bottom 1322, which is a problem present in existing artificial heart valve prostheses.

[0064] More in detail, such as Figure 7 as well as Figures 8a to 8b As shown, the leaflet fixing edge 132 includes a leaflet starting part 1321 and a leaflet bottom part 1322. The leaflet starting part 1321 is the junction of the leaflet fixing edge 132 and the leaflet connecting part 131, and the leaflet bottom part 1322 is the position of the leaflet fixing edge 132 closest to the inflow channel A. The leaflet starting part 1321 merges with the leaflet bottom part 1322 along the center of symmetry of the artificial leaflet 130 to form the leaflet fixing edge 132.

[0065] At the leaflet initiation portion 1321, a first tangent is drawn to the leaflet fixing edge 132. This first tangent passes through the leaflet initiation portion 1321 and is tangent to the leaflet fixing edge 132. The angle between this first tangent and the direction from the outflow channel B to the inflow channel A is the inclination angle at the initiation point. In the comparative embodiment, the inclination angle at the initiation point is θ1, which is the inclination angle at the initiation point of the leaflet fixing edge 132 shown by the solid line in the figure. Further, the inclination angle at the initiation point of the comparative embodiment is improved to obtain a new inclination angle at the initiation point as θ2, which is less than θ1. θ2 is the inclination angle at the initiation point of the leaflet fixing edge 132 shown by the dashed line in the figure. The improved leaflet fixing edge 132 is further away from the center of symmetry than the leaflet fixing edge 132 of the comparative embodiment, which increases the opening area of ​​the artificial leaflet 130 (i.e., the opening angle is larger).

[0066] like Figure 8c As shown, in the open state, the improved leaflet fixing edge 132 is further away from the central axis 110a of the stent, increasing the opening area of ​​the artificial leaflet 130. This allows for the drainage of blood stagnant at the leaflet bottom 1322, reducing the formation of a blood dead zone in the leaflet portion after the artificial leaflet 130 closes, and consequently reducing the formation of red blood clots 20. Preferably, the included angle θ2 at the improved starting point is 0°-15°, more preferably θ2 is 5°-10°, which maximizes the opening of the artificial leaflet 130 and guides the drainage of blood stagnant at the leaflet bottom 1322.

[0067] To address the issue of red blood clot formation, the bottom 1322 of the valve leaflet can be flattened. Flattening the bottom 1322 of the valve leaflet can also reduce the risk of blood flow stagnation and thus the risk of red blood clot formation.

[0068] like Figure 9As shown, in one embodiment, a second tangent is drawn to the fixed edge 132 of the leaflet at the bottom 1322 of the leaflet. The angle between the second tangent and the direction from the inflow channel A to the outflow channel B is defined as the bottom upper angle. In the comparative embodiment, the bottom upper angle is α1, which is the bottom upper angle of the leaflet bottom 1322 shown by the solid line in the figure. Furthermore, the traditional bottom upper angle α1 is improved to obtain a new bottom upper angle α2, which is greater than α1. α2 is the bottom upper angle of the leaflet bottom 1322 shown by the dashed line in the figure. It can be seen that the improved leaflet bottom 1322 is moved closer to the outflow channel B compared to the leaflet bottom 1322 of the comparative embodiment, making the leaflet bottom 1322 of the artificial leaflet 120 flatter. This can reduce the formation of blood dead zones in the leaflet portion after the artificial leaflet 130 is closed, thereby reducing the formation of red blood clots. Preferably, the improved bottom included angle α2 is 75°-90°, more preferably 80°-85°, so as to minimize the formation of blood dead zone in the leaflet after the artificial leaflet 130 is closed, thereby reducing the formation of red blood clots.

[0069] Figure 10 and Figure 11 In the comparative embodiment, the artificial valve leaflet 130 is sutured to the stent 110 on the inner side 110b of the stent. This creates a dead zone 30 of blood flow stagnation between the fixed edge 132 of the leaflet and the stent 110, which easily leads to the formation of red blood clots 20. Figure 10 This indicates that the leaflet fixing edge 132 passes through the support 110 from the inside out for suturing. Figure 11 This indicates that the leaflet fixing edge 132 is sutured inside the support 110b without passing through the support 110. Both suture methods will create a dead zone 30. It should be understood that the artificial leaflet 130 represented by the dashed line is in the open state, and the artificial leaflet 130 represented by the solid line is in the closed state. In this case, the dead zone 30 will inevitably exist at the leaflet bottom 1322 of the artificial leaflet 130.

[0070] like Figure 12 and Figure 13As shown, the present invention further improves the suturing method. The artificial valve leaflet 130 is sutured and fixed to the stent 110 by suture 140, and an external wrapping suturing method is adopted. That is, the leaflet fusion portion 131 is sutured to the stent rod at the stent window 113, and the leaflet fixing edge portion 132 is sutured to the stent suture rod 111 at the stent suture rod 111. The external wrapping suturing means that the artificial valve leaflet 130 is sewn on the outside of the stent 110c in a way that wraps the stent suture rod 111 and the stent rod. Specifically, the leaflet fusion portion 131 passes through the stent window 113 from the outside of the stent 110c and wraps the stent rod at the stent window 113 to the inside of the stent 110b, while the leaflet fixing edge portion 132 is fully or partially wrapped by the outside of the stent 110c. This external wrapping suturing method makes the blood inflow and outflow valves more open, avoids the formation of a dead zone 30 between the stent rod and the leaflet due to suturing, and avoids the formation of a red blood clot 20 due to blood flow stopping at this position.

[0071] When suturing the leaflet fixing edge 132, the spacing between the suture holes may be uniform or uneven, preferably uniform to ensure the tightness of the suture. Non-limitingly, when suturing the leaflet fixing edge 132, the spacing between adjacent suture holes in the extending direction of the support suture rod 111 can be 0.1mm-3mm, preferably 0.5mm-1.5mm. Furthermore, the distance from the suture hole to the edge of the leaflet fixing edge 132 can be 0.1mm-5mm, preferably 1mm-3mm. The suture holes on the artificial leaflet 130 can be pre-processed, such as by laser cutting, stamping, or other mechanical methods, or they can be formed by directly rubbing the artificial leaflet 130 with a suture needle.

[0072] like Figure 14 As shown, in one embodiment, the leaflet fixing edge 132 is fully wrapped and sutured to the stent suture rod 111, allowing blood to flow freely in and out when the artificial leaflet 130 opens and closes. This avoids dead zones formed between the stent rod and the artificial leaflet 130 due to suturing, preventing blood flow stagnation and the formation of red blood clots at this location. Here, "fully wrapped suture" means that the leaflet fixing edge 132 passes through the stent mesh 112 from the outer side 110c of the stent and enters the inner side 110b of the stent, fully wrapping the stent suture rod 111.

[0073] like Figure 15As shown, in another embodiment, the leaflet fixing edge 132 is sutured to the stent suture rod 111 in a partially wrapped manner, so that blood can flow freely in and out when the artificial leaflet 130 is opened and closed, avoiding dead zones formed between the stent rod and the artificial leaflet 130 due to suturing, and preventing blood flow stagnation and the formation of red blood clots at this location. Here, the partially wrapped suture refers to the leaflet fixing edge 132 partially wrapping the stent suture rod 111 on the outer side 110c of the stent without penetrating the stent mesh 112 into the inner side 110b of the stent. The partial wrapping is not limited to partial wrapping.

[0074] like Figure 16 As shown, the leaflet commissure 131 is sutured to the stent 110 at the stent window 113, typically using a full-coverage suture. This allows the leaflet commissure 131 to pass through the stent window 113 from the outside of the stent 110 to the inside, and then suture to itself. The leaflet commissure 131 fully covers the stent struts of the stent mesh 112. This design minimizes dead zones at the leaflet commissure 131 when the artificial leaflet 130 opens, preventing the formation of red blood clots.

[0075] In summary, the artificial heart valve provided by this invention has at least the following advantages:

[0076] First, the stent creates a blank area at the suture site of the leaflet fixation edge, which can minimize the dead area of ​​blood flow stagnation and reduce the risk of red blood thrombosis.

[0077] Secondly, the artificial valve leaflet was optimized by improving the angle at the starting point and increasing the opening area of ​​the artificial valve leaflet, which can further reduce the risk of blood flow stagnation and reduce the risk of red blood clot formation.

[0078] Third, the artificial valve leaflet was optimized by improving the bottom angle and making the bottom of the leaflet flat, which can further reduce the risk of blood flow stagnation and reduce the risk of red blood clot formation.

[0079] Fourth, the double-sided smooth artificial valve leaflets can reduce the risk of white thrombi formed due to rapid blood flow in the inflow tract;

[0080] Fifth, the external wrapping valve leaflet suturing method allows for more open blood flow in and out of the valve, avoiding dead zones formed between the stent and leaflets due to suturing, and further preventing blood flow stagnation at this location, which could lead to the formation of red blood clots.

[0081] Therefore, this invention reduces the blood flow stagnation area and lowers the risk of red thrombus formation in the valve leaflets by optimizing the stent, leaflet structure, and suturing process, and lowers the risk of white thrombus formation in the valve leaflets by optimizing the valve raw materials, thereby comprehensively improving the valve's anticoagulant capacity.

[0082] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0083] It should also be noted 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.

[0084] It should also be understood that, unless otherwise specified or indicated, the terms "first," "second," etc., in the specification are used only to distinguish the various components, elements, steps, etc. in the specification, and not to indicate the logical or sequential relationships between the various components, elements, steps, etc.

[0085] Furthermore, it should be recognized that the terminology described herein is used only to describe particular embodiments and not to limit the scope of the invention. It must be noted that the singular forms “a” and “an” used herein and in the appended claims include plural bases unless the context clearly indicates otherwise. For example, a reference to “a step” or “an apparatus” means a reference to one or more steps or apparatuses, and may include secondary steps and secondary apparatuses. All conjunctions used should be understood in the broadest sense. Also, the word “or” should be understood to have the definition of logical “or” rather than logical “exclusive OR”, unless the context clearly indicates otherwise. Furthermore, implementation of the methods and / or devices in embodiments of the invention may include performing selected tasks manually, automatically, or in combination.

Claims

1. An artificial heart valve, comprising a stent and artificial leaflets, wherein the artificial leaflets are connected to the stent, and the stent is axially divided into an inflow tract and an outflow tract, characterized in that, The outflow channel has multiple support stitching rods that are concave inward toward the inflow channel in an arc shape, and a blank area is formed on the side of the support stitching rods away from the inflow channel. The blank area is an open area without any support rods. Multiple support suture rods are arranged sequentially in the circumferential direction of the support. The two ends of two adjacent support suture rods are connected through the support window. The artificial leaflet includes a leaflet free edge, a leaflet connecting part, and a leaflet fixed edge. The two ends of the leaflet free edge and the leaflet fixed edge are connected through the leaflet connecting part. The leaflet fixed edge is sutured and fixed to the support suture rods, and the leaflet connecting part is sutured and fixed to the support window. The leaflet fixing edge has a leaflet starting part, which is located at the junction of the leaflet connecting part and the leaflet fixing edge. The leaflet fixing edge also has a first tangent line passing through the leaflet starting part. The first tangent line forms an angle at the starting point with the direction of the outflow channel pointing to the inflow channel. The angle at the starting point is 5°-10°. The leaflet fixing edge has a leaflet bottom, which is the position of the leaflet fixing edge closest to the inflow channel. The leaflet fixing edge also has a second tangent line passing through the leaflet bottom. The second tangent line forms a bottom upper angle with the direction of the inflow channel pointing to the outflow channel. The angle of the bottom upper angle is 75°-90°. The leaflet fusion portion passes through the support window from the outside of the support and wraps around the support rod at the support window from the inside of the support and is then sewn and fixed; the leaflet fixing edge enters from the outside of the support and fully wraps around the support suture rod and is then sewn and fixed, or the leaflet fixing edge partially wraps around the support rod from the outside of the support and is then sewn and fixed.

2. The artificial heart valve according to claim 1, characterized in that, The included angle at the bottom is 80°-85°.

3. The artificial heart valve according to claim 1, characterized in that, The surfaces of the artificial leaflets facing the inflow channel and the outflow channel are both smooth surfaces.

4. The artificial heart valve according to claim 3, characterized in that, The artificial leaflet is composed of two parts spliced ​​together, and / or the artificial leaflet is made of a double pericardium, with the pericardial connective tissue layers of the double pericardium facing each other.

5. The artificial heart valve according to claim 1, characterized in that, The leaflet fusion portion passes through the window of the support from the outside to the inside of the support and is then sutured and fixed to itself.

6. The artificial heart valve according to claim 1, characterized in that, The shape of the support window matches the shape of the leaflet junction.

7. The artificial heart valve according to claim 6, characterized in that, The bracket window is rectangular, square, or rhomboid in shape. The width of the bracket window in the circumferential direction of the bracket is 0.1mm-2mm, and the length of the bracket window in the axial direction of the bracket is 1mm-10mm.

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