Artificial heart valve

Abstract

The invention discloses an artificial heart valve, and relates to the technical field of medical instruments, the artificial heart valve comprises a support and three valve leaflets, the valve ring of the support is provided with a suture edge along the radial direction of the valve; each valve leaflet is provided with a fixed edge, a free edge and an underbelly; the lower abdomen is of a solid film structure and is realized by freely lofting and modeling from a fixed edge to a free edge; the fixed edge is fixed to the support, and the free edges of the three valve leaflets define a valve opening. The ratio of the axial height of the valve leaflets to the radius of the valve ring is 1-1.4; the angle between the tangent line of the top end of the fixed edge and the central axis of the valve is 15-25 degrees, simulation analysis shows that the stress of the whole valve leaflet can be reduced by adopting the size proportional relation, and the service life of the valve leaflet can be prolonged.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an artificial heart valve. Background Technology

[0002] Heart valves are vital structures connecting the atria and ventricles, or the ventricles and arteries. Each person has four valves in their heart: the aortic valve (connecting the left ventricle and the aorta), the pulmonary valve (connecting the right ventricle and the pulmonary artery), the mitral valve (connecting the left atrium and left ventricle), and the tricuspid valve (connecting the right atrium and right ventricle). These valves act as one-way valves, ensuring blood flows in only one direction and preventing backflow. Heart valve disease refers to organic lesions of these valves caused by damage from various pathogenic factors or congenital developmental abnormalities, primarily manifesting as valvular stenosis or insufficiency. This disease can ultimately lead to heart failure, thus affecting systemic blood circulation.

[0003] The application of artificial heart valves began in the 1960s and is one of the most important inventions in the field of medical devices. Based on the materials used to make them, artificial heart valves can be divided into mechanical valves (made from pyrolytic carbon) and bioprosthetic valves (made from biological tissues derived from pigs, cattle, etc.). Mechanical valves are designed to have a longer lifespan (over 50 years), but they have poor blood compatibility, are prone to adverse events such as thromboembolism, require lifelong anticoagulation therapy after surgery, and involve significant open-heart surgery. Bioprosthetic valves have better blood and tissue compatibility, requiring only anticoagulation for 3-6 months after surgery. However, because bioprosthetic valves are prone to calcification, their lifespan is shorter than that of mechanical valves (10-20 years), and some patients even experience valve failure shortly after replacement.

[0004] Ideally, a valve should possess excellent biocompatibility, anticoagulation, resistance to degradation and calcification, and high durability. The structure and properties of polymer materials offer flexible controllability. With careful design, high-performance polymer valves can be achieved, potentially combining the advantages of both mechanical and biological valves. These valves would possess excellent fatigue resistance and superior blood compatibility, leading many cardiologists to consider them the future of heart valves. However, if the shape of the polymer valve is not properly optimized, stress concentration issues can occur in the valve leaflets during operation, affecting the valve's lifespan.

[0005] For those skilled in the art, how to reduce leaflet stress is a technical problem that needs to be solved. Summary of the Invention

[0006] The core of this invention is to provide an artificial heart valve that defines the size relationship of the leaflets, resulting in less stress concentration and a larger opening area, which helps to extend the lifespan of the leaflets. The specific solution is as follows:

[0007] An artificial heart valve includes a stent and three leaflets; the stent is used to fix it in the body; the leaflets are fixedly disposed on the stent, and each leaflet has a fixed side, a free side, and a lower abdomen; the lower abdomen is realized by free lofting modeling from the fixed side to the free side.

[0008] The fixed edge is fixed to the bracket, and the free edges of the three leaflets together form a valve opening;

[0009] The ratio of the axial height of the leaflet to the radius of the valve annulus is between 1 and 1.4; the angle between the tangent at the top of the fixed edge and the central axis of the valve is between 15 and 25 degrees.

[0010] Optionally, the ratio of the total length of the free side of each of the leaflets to the radius of the leaflet ring is between 1.98 and 2.04.

[0011] Optionally, the fixed edge is a curve formed around a cylinder or cone;

[0012] The free edge is located on a plane perpendicular to the central axis of the valve.

[0013] Optionally, the fixed edge is a spline curve with 5 constraint points;

[0014] The first fixed constraint point and the fifth fixed constraint point are two flush vertices; the third fixed constraint point is the bottom point located on the plane of symmetry between the first fixed constraint point and the fifth fixed constraint point.

[0015] The second fixed constraint point is located between the first fixed constraint point and the third fixed constraint point, and the fourth fixed constraint point is located between the third fixed constraint point and the fifth fixed constraint point;

[0016] The second fixed constraint point causes the first fixed constraint point and the third fixed constraint point to form an outwardly convex arch; the fourth fixed constraint point causes the third fixed constraint point and the fifth fixed constraint point to form an outwardly convex arch.

[0017] Optionally, the free edge is a spline curve with 7 constraint points;

[0018] The first and seventh free constraint points are located at the endpoints of the fixed side, and the fourth free constraint point is closer to the valve central axis relative to the line connecting the first and seventh free constraint points.

[0019] The second and third free constraint points are located between the first and fourth free constraint points, and the fifth and sixth free constraint points are located between the fourth and seventh free constraint points.

[0020] The second and third free constraint points form an outwardly convex arch between the first and fourth free constraint points, and the fifth and sixth free constraint points form an outwardly convex arch between the fourth and seventh free constraint points.

[0021] Optionally, the abdomen is prepared by dip coating or spray coating process.

[0022] Optionally, the thickness of the lower abdomen is between 0.15 and 0.6 mm.

[0023] Optionally, the material of the leaflet is a polymer or a fiber-reinforced polymer;

[0024] The polymer includes any one of polyether polyurethane, polyester polyurethane, polysiloxane polyurethane, polyisobutylene elastomer, and polystyrene elastomer; the fiber includes one or more of polyester fiber, polytetrafluoroethylene fiber, and polyurethane fiber.

[0025] Optionally, the stent is a balloon dilatation stent or a self-expanding stent;

[0026] And / or, the stent is a surgical valve stent or an interventional valve stent.

[0027] Optionally, the material of the support includes any one of polymer, stainless steel, nickel-titanium alloy, and cobalt-chromium-tungsten alloy.

[0028] This invention provides an artificial heart valve, comprising a stent and three leaflets. The stent is used to fix the valve in the body. Each leaflet has a fixed side, a free side, and a ventral region. The ventral region is a solid thin-film structure, which is created by free-layout modeling from the fixed side to the free side. The fixed side is fixed to the stent, and the free sides of the three leaflets together form the valve opening. The ratio of the axial height of the leaflet to the radius of the valve annulus is between 1 and 1.4. The angle between the tangent at the top of the fixed side and the central axis of the valve is between 15 and 25 degrees. Through simulation analysis, it is found that using this dimensional ratio can reduce the stress on the entire leaflet and help improve its service life. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the flattened leaflet state of the artificial heart valve of the present invention;

[0031] Figure 2A This is a schematic diagram of Embodiment 1 of the artificial heart valve of the present invention in a free state;

[0032] Figure 2B This is a schematic diagram of the stress distribution in the open state of the valve in Example 1;

[0033] Figure 2C This is a schematic diagram of the stress distribution in the valve closure state in Example 1;

[0034] Figure 3A This is a schematic diagram of Embodiment 2 of the artificial heart valve of the present invention in a free state;

[0035] Figure 3B This is a schematic diagram of the stress distribution in the open state of the valve in Example 2;

[0036] Figure 3C This is a schematic diagram of the stress distribution in the valve closure state in Example 2;

[0037] Figure 4A This is a schematic diagram of Embodiment 3 of the artificial heart valve of the present invention in a free state;

[0038] Figure 4B This is a schematic diagram of the stress distribution in the open state of the valve in Example 3;

[0039] Figure 4C This is a schematic diagram of the stress distribution in the valve closure state in Example 3;

[0040] Figure 5A This is a schematic diagram of Comparative Example 1 in a free state;

[0041] Figure 5B This is a schematic diagram of the stress distribution in the open state of the valve in Comparative Example 1.

[0042] Figure 5C This is a schematic diagram of the stress distribution in the valve closure state in Comparative Example 1.

[0043] Figure 6A This is a schematic diagram of Comparative Example 2 in a free state;

[0044] Figure 6B This is a schematic diagram of the stress distribution in the open state of Comparative Example 2;

[0045] Figure 6C This is a schematic diagram of the stress distribution in the closed state of Comparative Example 2.

[0046] The image includes:

[0047] 10. Frame; 101. 102. 102. 20. 20. 201. 202. 203. 203. Detailed Implementation

[0048] To enable those skilled in the art to better understand the technical solution of the present invention, the artificial heart valve of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0049] The artificial heart valve provided by this invention can be implanted into the body through open-heart surgery, minimally invasive surgery, and transcatheter interventional implantation when heart valve disease occurs, replacing the valve in the corresponding position in the body.

[0050] Combination Figure 2A As shown, the artificial heart valve of the present invention includes a stent 10 and three leaflets 20. The stent 10 provides support, and the leaflets 20 are fixed on the stent 10. An artificial heart valve has a stent 10 and three leaflets 20. The three leaflets 20 are centrally symmetrically distributed, and the central axis of symmetry is the central axis of the stent 10.

[0051] The main body of the stent 10 is cylindrical, allowing blood to circulate within it. Figure 2A The flow direction in the middle is unidirectional, from bottom to top; Figure 2A In the stent 10, the lower edge of the main body is a valve annulus 101, which is circular and provides support. For artificial heart valves that need to be sutured and fixed in the body, a suture edge 102 is provided at the valve annulus 101 of the stent 10 along the radial direction of the valve. The suture edge 102 is a solid structure, and its surface is approximately perpendicular to the axis of the stent 10, forming a radially outward extending protrusion at the valve annulus 101.

[0052] The suture edge 102 forms a complete solid sheet-like annular structure around the valve ring 101. The suture edge 102 is used to suture with human tissue when implanted into the body, thereby fixing the stent 10 and thus fixing and positioning the entire artificial heart valve.

[0053] Each leaflet 20 is independently fixed to the bracket 10, combined with Figure 1 , Figure 2A As shown, each leaflet 20 has a fixed edge 201, a free edge 202, and a lower abdomen 203. The fixed edge 201 is the edge connected to the support 10, and the free edge 202 is the edge that is not fixed. The fixed edge 201 and the free edge 202 together form the edge contour of the entire leaflet 20. Figure 1 As shown, in the unfolded state, the shape of the fixed side 201 is approximately parabolic, and the fixed side 201 itself is axially symmetric; the shape of the free side 202 is an irregular curve that is high in the middle and low at both ends, and the free side 202 itself is axially symmetric.

[0054] The lower abdomen 203 is modeled by free lofting from the fixed edge 201 to the free edge 202. The lower abdomen 203 is the solid part of the leaf 20, and the thickness of the lower abdomen 203 is basically the same at all positions.

[0055] Combination Figure 2A As shown, the fixed side 201 is fixed to the stent 10, and the free sides 202 of the three leaflets 20 surround to form the valve opening. The fixed side 201 is fixed and limited by the stent 10. During the blood flow process, the fixed side 201 remains fixed and does not move, while the free side 202 is not constrained. Therefore, it opens and closes periodically during the blood flow process.

[0056] like Figure 2A As shown, when blood flows from one end of the valve ring 101 to the other end of the free side 202, the blood causes the three valve leaflets 20 to expand outward; when blood flows from one end of the free side 202 to the other end of the valve ring 101, the three valve leaflets 20 are squeezed and closed by the blood, blocking the blood from flowing in the opposite direction.

[0057] When the leaflet 20 is installed on the stent 10 to form a three-dimensional artificial heart valve, the ratio of the axial height of the leaflet 20 to the radius of the valve annulus 101 is between 1 and 1.4, including two endpoint values. The axial height of the leaflet 20 is also the projected length of the leaflet 20 on the central axis of the artificial heart valve, and the radius of the valve annulus 101 is the distance from any point on the valve annulus 101 to the central axis of the artificial heart valve.

[0058] With leaflet 20 flattened in a planar state, the angle between the tangent at the top of fixed edge 201 and the central axis of the artificial heart valve is between 15 and 25 degrees, including both endpoint values. Figure 1 As shown, the included angle α represents the angle between the right top tangent of the fixed side 201 and the central axis of the artificial heart valve, where 15°≦α≦25°.

[0059] By adopting the above-mentioned size ratio constraint relationship, the valve opening area is larger, and the stress concentration problem during the opening and closing stages is smaller. Through simulation analysis, the stress of the entire leaflet 20 can be reduced, which helps to improve the service life of the leaflet.

[0060] Building upon the aforementioned scheme, further, the ratio of the total length of the free edge 202 of each leaflet 20 to the radius of the leaf ring 101 is between 1.98 and 2.04, including two endpoint values, combined with... Figure 1 As shown, the free edge 202 of the leaflet 20 is an irregular curve, and the total length of the free edge 202 of the leaflet 20 is the total length of the curve of the free edge 202. The radius of the valve annulus 101 is the distance from any point on the valve annulus 101 to the central axis of the artificial heart valve. With this dimensional relationship, the valve opening area is larger, and the stress concentration problem during the opening and closing phases is smaller.

[0061] Furthermore, the fixed edge 201 is a spatial curve formed around the surface of a rotating body such as a cylinder or cone. When the support 10 is a cylinder, the curve is formed using constraint points and then projected onto the cylindrical surface to form the fixed edge 201. When the support 10 is a cone, the curve is formed using constraint points and then projected onto the conical surface to form the fixed edge 201.

[0062] In the free state, the free edge 202 is located on a plane perpendicular to the central axis of the valve. The plane containing the free edge 202 is perpendicular to the central axis of the valve at 90 degrees, ensuring that the free edge 202 is precisely parallel to the radial plane of the valve in spatial orientation.

[0063] Specifically, fixed edge 201 is a spline curve with 5 constraint points, combined with Figure 1 As shown, the five constraint points of fixed edge 201 are B1, B2, B3, B4, and B5, which are the first fixed constraint point, the second fixed constraint point, the third fixed constraint point, the fourth fixed constraint point, and the fifth fixed constraint point, respectively. The first fixed constraint point B1 and the second fixed constraint point B2 are symmetrical with the fourth fixed constraint point B4 and the fifth fixed constraint point B5 about a plane passing through the third fixed constraint point B3 and the central axis.

[0064] The first fixed constraint point B1 and the fifth fixed constraint point B5 are two flush vertices. The first fixed constraint point B1 and the fifth fixed constraint point B5 are located in the same plane perpendicular to the central axis, and both are the highest points of the fixed edge 201.

[0065] The third fixed constraint point B3 is the bottom point located on the plane of symmetry between the first fixed constraint point B1 and the fifth fixed constraint point B5, and the third fixed constraint point B3 is the lowest point of the fixed edge 201.

[0066] The second fixed constraint point B2 is located between the first fixed constraint point B1 and the third fixed constraint point B3, and the fourth fixed constraint point B4 is located between the third fixed constraint point B3 and the fifth fixed constraint point B5. The second fixed constraint point B2 and the fourth fixed constraint point B4 are located on the same plane perpendicular to the central axis. The second fixed constraint point B2 and the fourth fixed constraint point B4 can be selected at half the height of the first fixed constraint point B1 and the third fixed constraint point B3.

[0067] The second fixed constraint point B2 forms an outwardly convex arch between the first fixed constraint point B1 and the third fixed constraint point B3; the fourth fixed constraint point B4 forms an outwardly convex arch between the third fixed constraint point B3 and the fifth fixed constraint point B5. The two arches are axially symmetrically distributed, forming a spatial curve that approximates a parabola. The bracket 10, used to connect the fixed edge 201, adopts the same shape as the fixed edge 201.

[0068] Specifically, free edge 202 is a spline curve with 7 constraint points; combined with Figure 1 As shown, the seven constraint points of free edge 202 are A1, A2, A3, A4, A5, A6, and A7, which are respectively the first, second, third, fourth, fifth, sixth, and seventh free constraint points. When the leaflet 20 is flattened, free edge 202 is higher in the middle and lower at both ends. In a three-dimensional spatial state fixed to the support 10, as shown... Figure 2A In the free state, the leaflet 20 is not subject to external force, and all positions of the free edge 202 are located on the same plane and have the same height.

[0069] The first free constraint point A1 and the seventh free constraint point A7 are located at the endpoints of the fixed edge 201, and they are located in the same plane perpendicular to the central axis.

[0070] The fourth free constraint point A4 is closer to the valve's central axis than the line connecting the first free constraint point A1 and the seventh free constraint point A7; combined with Figure 2A As shown, the three lines connecting the first free constraint point A1 and the seventh free constraint point A7 of the three leaflets 20 form an equilateral triangle. The fourth free constraint point A4 is closer to the valve's central axis relative to the connecting lines.

[0071] The second free constraint point A2 and the third free constraint point A3 are located between the first free constraint point A1 and the fourth free constraint point A4, and the fifth free constraint point A5 and the sixth free constraint point A6 are located between the fourth free constraint point A4 and the seventh free constraint point A7.

[0072] Combination Figure 2A As shown, the second free constraint point A2 and the third free constraint point A3 form an outwardly convex arch between the first free constraint point A1 and the fourth free constraint point A4, and the curve between the first free constraint point A1 and the fourth free constraint point A4 deviates from its adjacent leaflet 20. The fifth free constraint point A5 and the sixth free constraint point A6 form an outwardly convex arch between the fourth free constraint point A4 and the seventh free constraint point A7, and the curve between the fourth free constraint point A4 and the seventh free constraint point A7 deviates from its adjacent leaflet 20.

[0073] Based on any of the above technical solutions and their combinations, the abdomen 203 of the present invention is prepared by dip coating or spray coating process; the abdomen 203 is a functional component prepared by surface treatment process, mainly processed by dip coating or spray coating process.

[0074] A mold for forming the leaflet 20 is prepared in advance. During the preparation process, the mold is pre-treated to ensure surface cleanliness and adhesion. Then, depending on the specific requirements, a dip coating process is selected: the component is completely immersed in the coating, and the coating thickness is adjusted by controlling the immersion time and the lifting speed; or a spray coating process is used: the coating is uniformly atomized and adhered to the mold surface using professional spraying equipment, and the ideal coating effect is obtained by adjusting the spraying pressure and angle. Both processes can effectively form a uniform and dense functional coating, namely the abdomen 203, on the mold surface. During dip coating or spray coating, the prepared support 10 is fixed to the mold in advance. When forming the leaflet 20, the leaflet 20 and the support 10 are fixed together.

[0075] Traditional bioprosthetic heart valves are created by cutting porcine or bovine pericardium into valve leaflets, which are then sutured to a heart valve stent to form a complete implantable heart valve. However, the three-dimensional structure of the valve leaflets cannot be precisely optimized and modified. This invention uses a polymer valve, whose leaflet morphology is precisely designed and can be precisely optimized through simulation analysis technology, which helps to improve the lifespan of the artificial heart valve.

[0076] The thickness of the lower abdomen 203 is between 0.15-0.6 mm, including the two endpoint values. The thickness of the human native valve is about 0.2-0.4 mm. Therefore, in order to ensure the normal use of the valve, the thickness of the formed artificial heart valve leaflet 20 should be between 0.15-0.6 mm, preferably between 0.15-0.45 mm.

[0077] The material of the leaflet 20 is a polymer, including any one of polyether polyurethane, polyester polyurethane, polysiloxane polyurethane, polyisobutylene elastomer, and polystyrene elastomer.

[0078] The material of the leaflet 20 can also be a fiber-reinforced polymer, including any one of polyether polyurethane, polyester polyurethane, polysiloxane polyurethane, polyisobutylene elastomer, and polystyrene elastomer; the fiber includes one or more of polyester fiber, polytetrafluoroethylene fiber, and polyurethane fiber. Adding fine fiber filaments to the polymer material layer enhances structural strength.

[0079] Stent 10 is either a balloon-expandable stent or a self-expanding stent. Balloon-expandable stents require balloon inflation for expansion, and the stent is fixed after plastic deformation; they are mostly made of stainless steel or cobalt-chromium alloy. Self-expanding stents rely on their own elastic restoring force to deploy on their own, without the need for a balloon; they are mostly made of nickel-titanium alloy.

[0080] Stent 10 can be a surgical valve stent or an interventional valve stent. Surgical valve stents require a midline thoracotomy or a small right thoracotomy, cardiopulmonary bypass, and must be implanted while the heart is stopped. Interventional valve stents are delivered via catheter through punctures such as the femoral artery or the apex of the heart and can be implanted while the heart is beating.

[0081] The material of the support 10 includes any one of polymer, stainless steel, nickel-titanium alloy, and cobalt-chromium-tungsten alloy.

[0082] The following five specific dimensions are listed for simulation analysis. The leaflet thickness is set to 0.2 mm, and the material is TPU (IROGRAN A 80 P5039) tensile test data.

[0083] Example 1: As Figure 2A The image shows a design scheme for an artificial heart valve. In this embodiment, the ratio of leaflet height H to valve annulus radius R is 1.18; the angle between the tangent at the top of the fixed edge 201 of the leaflet and the central axis of the valve is 20 degrees; and the ratio of the free edge 202 of the leaflet to valve annulus radius R is 1.88.

[0084] Through simulation, the opening phase is as follows: Figure 2B As shown, the maximum opening area (GOA) is approximately 2.2 cm². 2 The maximum stress is approximately 5.9 × 10⁻⁶. 6 dyne / cm 2 ; Closure phase such as Figure 2C As shown, the maximum stress is approximately 3.09 × 10⁻⁶. 6 dyne / cm 2 .

[0085] Example 2: Figure 3A The diagram shows another design scheme for an artificial heart valve. In this embodiment, the ratio of leaflet height H to annular radius R is 1.18; the angle between the tangent at the top of the fixed edge 201 of the leaflet and the axis is 18 degrees; and the ratio of the free edge 202 of the leaflet to annular radius R is 1.96.

[0086] Through simulation, the opening phase is as follows: Figure 3B As shown, the maximum opening area GOA is approximately 2.16 cm². 2 The maximum stress is approximately 2.53 × 10⁻⁶. 6 dyne / cm 2 ; Closure phase such as Figure 3C As shown, the maximum stress is approximately 2.7 × 10⁻⁶. 6 dyne / cm 2 .

[0087] Example 3: As Figure 4AThe diagram shows another design scheme for an artificial heart valve. In this embodiment, the ratio of leaflet height H to annular radius R is 1.18; the angle between the tangent at the top of the fixed edge 201 of the leaflet and the axis is 18 degrees; and the ratio of the free edge 202 of the leaflet to annular radius R is 2.02.

[0088] Through simulation, the opening phase is as follows: Figure 4B As shown, the maximum opening area GOA is approximately 2.5 cm². 2 The maximum stress is approximately 2.33 × 10⁻⁶. 6 dyne / cm 2 ; Closure phase such as Figure 4C As shown, the maximum stress is approximately 2.65 × 10⁻⁶. 6 dyne / cm 2 .

[0089] Comparative Example 1: Figure 5A The figure shows another design scheme for an artificial heart valve. In this embodiment, the ratio of leaflet height H to annular radius R is 1.18; the angle between the tangent at the top of the fixed edge 201 of the leaflet and the axis is 5 degrees; and the ratio of the free edge 202 of the leaflet to annular radius R is 2.02.

[0090] Through simulation, the opening phase is as follows: Figure 5B As shown, the maximum opening area GOA is approximately 2.1 cm². 2 The maximum stress is approximately 0.88 × 10⁻⁶. 6 dyne / cm 2 ; Closure phase such as Figure 5C As shown, the maximum stress is approximately 10.7 × 10⁻⁶. 6 dyne / cm 2 .

[0091] Comparative Example 2: Figure 6A The diagram shows another design scheme for an artificial heart valve. In this embodiment, the ratio of leaflet height H to annular radius R is 1.6; the angle between the tangent at the top of the fixed edge 201 of the leaflet and the axis is 0 degrees; and the ratio of the free edge 202 of the leaflet to annular radius R is 1.84.

[0092] Through simulation, the opening phase is as follows: Figure 6B As shown, the maximum opening area GOA is approximately 1.9 cm². 2 The maximum stress is approximately 1.61 × 10⁻⁶. 6 dyne / cm 2 ; Closure phase such as Figure 6C As shown, the maximum stress is approximately 11 × 10⁻⁶. 6 dyne / cm 2 .

[0093] By comparing Examples 1-3 and Comparative Examples 1-2 (Table 1), it can be seen that Example 3 (the ratio of leaflet height H to annular radius R is 1.18; the angle between the tangent at the top of the fixed leaflet edge 41 and the axis is 18 degrees; the ratio of the free leaflet edge 42 to annular radius R is 2.02) has the largest valve opening area and the least stress concentration problem. Therefore, the design of each characteristic parameter in this vicinity should best ensure a larger valve opening area and a smaller stress concentration.

[0094] The artificial heart valve provided by the present invention includes a stent 10 and three leaflets 20. Each leaflet 20 is composed of a fixed side 201, a free side 202 and a lower part 203. All three components are specially designed and optimized to achieve the minimum stress concentration and the maximum opening area of ​​the valve during the opening and closing process of the heart valve, thereby improving the service life of the artificial heart valve.

[0095]

[0096] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An artificial heart valve, characterized in that, It includes a stent (10) and three leaflets (20); the stent (10) is used for fixation in the body; The leaflets (20) are fixedly mounted on the support (10), and each leaflet (20) is provided with a fixed side (201), a free side (202) and a lower abdomen (203); the lower abdomen (203) is realized by free lofting modeling from the fixed side (201) to the free side (202); The fixed edge (201) is fixed to the bracket (10), and the free edges (202) of the three leaflets (20) surround to form a valve opening; The ratio of the axial height of the leaflet (20) to the radius of the annulus (101) is between 1 and 1.4; the angle between the tangent at the top of the fixed edge (201) and the central axis of the valve is between 15 and 25 degrees.

2. The artificial heart valve according to claim 1, characterized in that, The ratio of the total length of the free edge (202) of each of the leaflets (20) to the radius of the leaflet ring (101) is between 1.98 and 2.

04.

3. The artificial heart valve according to claim 1, characterized in that, The fixed edge (201) is a curve formed around a cylinder or cone; The free edge (202) is located on a plane perpendicular to the central axis of the valve.

4. The artificial heart valve according to claim 3, characterized in that, The fixed edge (201) is a spline curve with 5 constraint points; The first fixed constraint point and the fifth fixed constraint point are two flush vertices; the third fixed constraint point is the bottom point located on the plane of symmetry between the first fixed constraint point and the fifth fixed constraint point. The second fixed constraint point is located between the first fixed constraint point and the third fixed constraint point, and the fourth fixed constraint point is located between the third fixed constraint point and the fifth fixed constraint point; The second fixed constraint point causes the first fixed constraint point and the third fixed constraint point to form an outwardly convex arch; the fourth fixed constraint point causes the third fixed constraint point and the fifth fixed constraint point to form an outwardly convex arch.

5. The artificial heart valve according to claim 3, characterized in that, The free edge (202) is a spline curve with 7 constraint points; The first and seventh free constraint points are located at the endpoints of the fixed side (201), and the fourth free constraint point is closer to the valve central axis relative to the line connecting the first and seventh free constraint points. The second and third free constraint points are located between the first and fourth free constraint points, and the fifth and sixth free constraint points are located between the fourth and seventh free constraint points. The second and third free constraint points form an outwardly convex arch between the first and fourth free constraint points, and the fifth and sixth free constraint points form an outwardly convex arch between the fourth and seventh free constraint points.

6. The artificial heart valve according to any one of claims 1 to 5, characterized in that, The abdomen (203) is prepared by dip coating or spray coating process.

7. The artificial heart valve according to claim 6, characterized in that, The thickness of the lower abdomen (203) is between 0.15 and 0.6 mm.

8. The artificial heart valve according to claim 6, characterized in that, The material of the leaflet (20) is a polymer or a fiber-reinforced polymer; The polymer includes any one of polyether polyurethane, polyester polyurethane, polysiloxane polyurethane, polyisobutylene elastomer, and polystyrene elastomer; the fiber includes one or more of polyester fiber, polytetrafluoroethylene fiber, and polyurethane fiber.

9. The artificial heart valve according to any one of claims 1 to 5, characterized in that, The stent (10) is a balloon dilatation stent or a self-expanding stent; And / or, the stent (10) is a surgical valve stent or an interventional valve stent.

10. The artificial heart valve according to claim 9, characterized in that, The material of the support (10) includes any one of polymer, stainless steel, nickel-titanium alloy, and cobalt-chromium-tungsten alloy.

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