CN112190365A - Artificial heart valve leaflet and heart valve prosthesis - Google Patents

Abstract

The invention relates to a prosthetic heart valve leaflet and a heart valve prosthesis, which comprise at least two small leaves distributed in a ring shape, wherein each small leaf comprises a main body wall and a closing wall which are connected in the axial direction; wherein: the artificial heart valve leaflet has a closed state and an open state; the leaflets are configured such that when the prosthetic heart valve leaflet is in the open state, the closed walls of the leaflets separate; the leaflets are further configured such that when the prosthetic heart valve leaflet is in the closed state, body walls of adjacent leaflets at least partially overlap to cause circumferential closure of the prosthetic heart valve leaflet while closure walls of adjacent leaflets at least partially overlap to cause axial closure of the prosthetic heart valve leaflet. The artificial heart valve leaflet has the advantage that the artificial heart valve leaflet can be completely closed so as to reduce the generation of large trans-valve pressure difference.

Description

Artificial heart valve leaflet and heart valve prosthesis

Technical Field

The invention relates to the technical field of medical instruments, in particular to an artificial heart valve leaflet and a heart valve prosthesis.

Background

The heart valve includes an aortic valve that joins the left ventricle and the aorta, a pulmonary valve that joins the right ventricle and the pulmonary artery, a mitral valve that joins the left atrium and the left ventricle, and a tricuspid valve that joins the right atrium and the right ventricle. All the heart valves play the role of one-way valves, and the heart valves are opened and closed rhythmically along with the rhythmic contraction and relaxation of the heart in the blood circulation, so that the blood smoothly passes through the valve openings and is prevented from flowing backwards, and the blood circularly flows in a certain direction in the body. When the heart valve is inflamed, the problems of structural damage, fibrosis, adhesion, shortening, myxoma-like lesion, ischemic necrosis, calcium precipitation and the like can be caused, and the normal blood circulation is influenced, so that the heart valve disease is called.

Prosthetic heart valve leaflets are artificial organs that can be implanted into the heart to work in place of heart valves. When the heart valve is seriously ill and cannot be restored and the valve function is improved by adopting valve separation or repair, artificial heart valve replacement is necessary. However, the existing artificial heart valve leaflet still has the problems of insufficient closure height and insufficient leaflet coaptation area, which cause the insufficiency of the artificial heart valve leaflet. When the artificial heart valve leaflet is not completely closed, partial blood backflow can be caused, and large trans-valve pressure difference is caused, and the trans-valve pressure difference is an important hemodynamic parameter for evaluating the function of the artificial heart valve leaflet. Specifically, after the artificial cardiac valve leaflet is implanted into a human body, when blood flows through a valve orifice, the blocking effect of the artificial cardiac valve leaflet on the blood flow generates a trans-valve pressure difference, the greater the velocity gradient of the blood flow, and the shear stress generated by the trans-valve pressure difference is increased, and once the shear stress exceeds a threshold value for damaging blood components, hemolysis or sub-hemolysis can be caused, and even vascular endothelial cells can be damaged.

Disclosure of Invention

The invention aims to provide an artificial heart valve leaflet and a heart valve prosthesis, which can be fully closed to avoid backflow and further avoid generating large trans-valve pressure difference.

In order to achieve the above objects, the present invention provides a prosthetic heart valve leaflet comprising at least two leaflets distributed in a ring shape, and each of the leaflets comprises a main body wall and a closing wall connected in an axial direction; wherein:

the artificial heart valve leaflet has a closed state and an open state;

the leaflets are configured such that when the prosthetic heart valve leaflet is in the open state, the closed walls of the leaflets separate;

the leaflets are further configured such that when the prosthetic heart valve leaflet is in the closed state, body walls of adjacent leaflets at least partially overlap to cause circumferential closure of the prosthetic heart valve leaflet while closure walls of adjacent leaflets at least partially overlap to cause axial closure of the prosthetic heart valve leaflet.

Optionally, the leaflets are further configured such that when the prosthetic heart valve leaflet is in the open state, body walls of adjacent leaflets at least partially overlap.

Optionally, when the artificial heart valve leaflet is in the closed state, the artificial heart valve leaflet is in a funnel-shaped structure and the closing walls of adjacent leaflets at least partially overlap to close the tips of the funnel-shaped structure.

Optionally, the leaflets are configured to be automatically repositioned upon release of the external force to enable the prosthetic heart valve leaflet to return from the open state to the closed state.

Optionally, the leaflets are configured to be automatically contractible upon release of an external force to enable the prosthetic heart valve leaflet to return from the open state to the closed state.

Optionally, the leaflet has an elastic modulus of 0.2GPa to 2.5 GPa.

Optionally, the leaflets are made of a shape memory material.

Optionally, the body wall comprises an engaging wall, a curved wall and an extending wall connected in sequence in the axial direction; the curved wall is arc-shaped in the axial section of the artificial heart valve leaflet; the extension wall is connected with the closing wall;

when the artificial heart valve leaflet is in the open state, the curved walls of adjacent leaflets at least partially overlap and the extended walls of adjacent leaflets at least partially overlap.

Optionally, an end surface of the engaging wall away from the curved wall is taken as a reference surface, an included angle between the extending wall and the reference surface is β, an included angle between the closing wall and the reference surface is α, and α > β.

Optionally, an angle between a tangent line at a connection point of the joining wall and the curved wall and the reference plane is θ, an angle between a tangent line at a connection point of the curved wall and the extending wall and the reference plane is γ, and α > γ > β, γ < θ.

Optionally, alpha is more than or equal to 30 degrees and less than or equal to 90 degrees, beta is more than or equal to 30 degrees and less than or equal to 90 degrees, gamma is more than or equal to 30 degrees and less than or equal to 90 degrees, and theta is more than or equal to 60 degrees and less than or equal to 90 degrees.

Further, to achieve the above object, the present invention provides a heart valve prosthesis comprising:

a stent having opposing inflow and outflow ends; and

the artificial heart valve leaflet is arranged in the bracket, and the main body wall is connected with the bracket.

Optionally, the body wall includes an engagement wall, a curved wall, and an extension wall connected in series in the axial direction, wherein the engagement wall is connected with the inflow end of the holder.

Optionally, the stent has a stent annulus position corresponding to an annulus of a heart, and the attachment position of the body wall and the closure wall corresponds to the stent annulus position when the prosthetic heart valve leaflet is in the closed state.

Optionally, the skirt comprises an inner skirt and an outer skirt which are connected with each other; the inner skirt is arranged on the inner side surface of the inflow end of the bracket; the outer skirt edge is arranged on the outer side surface of the inflow end of the support, and the edge of the outer skirt edge is wavy.

Compared with the prior art, the artificial heart valve leaflet and the heart valve prosthesis have the following advantages:

first, the artificial heart valve leaflet of the present invention comprises at least two leaflets, and each leaflet has a main body wall and a closing wall arranged in sequence from an inflow end to an outflow end of a heart valve prosthesis, wherein when the artificial heart valve leaflet is in a closed state, the main body walls of adjacent leaflets at least partially coincide, and the closing walls of adjacent leaflets also at least partially overlap such that the artificial heart valve leaflet is closed.

Second, when the heart valve is in the open position, the body walls of adjacent leaflets still partially overlap, which ensures complete closure of the heart valve in the closed position.

Thirdly, the leaflets of the invention can be automatically restored after the external force is relieved, so that the artificial heart valve leaflet can be automatically closed, and the problem of incomplete closure caused by the deviation of the implantation position can be avoided. For this purpose, the leaflets are preferably made of a material having an elastic modulus of 0.2GPa to 2.5GPa or a shape memory material so that the prosthetic heart valve leaflet automatically returns to the closed state after opening following contraction of the heart.

Fourthly, the connecting position of the main body wall and the closing wall is equivalent to the position of a bracket valve ring of the bracket, which is beneficial to improving the closing height of the artificial heart valve leaflet and further improving the closing performance of the artificial heart valve leaflet.

Drawings

Fig. 1a is a top view of a prosthetic heart valve leaflet according to an embodiment of the present invention, illustrating the prosthetic heart valve leaflet in a closed state;

fig. 1b is a top view of the prosthetic heart valve leaflet of fig. 1a in an open state;

fig. 2 is a schematic structural view of leaflets of the artificial heart valve leaflet according to an embodiment of the present invention;

FIG. 3 is a schematic structural view of the leaflets shown in FIG. 1a being stacked to form a prosthetic heart valve leaflet;

FIGS. 4a and 4b are schematic structural views of leaflets provided in accordance with an embodiment of the invention;

FIG. 5 is a schematic illustration of the slope relationship of leaflets provided by the invention according to an embodiment;

fig. 6a is a schematic structural view of a heart valve prosthesis according to an embodiment of the invention, in which the artificial heart valve leaflets are in a closed state;

fig. 6b is a schematic structural view of a heart valve prosthesis according to an embodiment of the invention, in which the artificial heart valve leaflet is in an open state;

FIG. 7 is a schematic diagram of the construction of a skirt of a heart valve prosthesis according to one embodiment of the present invention.

In the figure:

1000-artificial heart valve leaflet;

1100-leaflets; 1100 a-first leaflet, 1100 b-second leaflet, 1100 c-third leaflet, 1140 d-fourth leaflet;

1110-a body wall;

1111-mating wall, 1112-curved wall, 1113-extension wall;

1120-a closure wall;

2000-bracket;

2100-inflow end, 2200-outflow end;

3000-skirt;

3100 inner skirt, 3200 outer skirt.

Detailed Description

In order to make the objects, advantages and features of the present invention more apparent, embodiments of the artificial heart valve leaflet and the heart valve prosthesis according to the present invention will be described in detail with reference to the accompanying drawings. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.

As used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural referents, and the plural forms "a plurality" includes two or more referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise, and the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either fixedly connected, detachably connected, or integrally connected. Either mechanically or electrically. Either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations. The same or similar reference numbers in the drawings identify the same or similar elements.

The leaflets mentioned in the following description, unless stated as native leaflets, refer uniformly to prosthetic heart leaflets.

Referring to fig. 1a and 1b in conjunction with fig. 2 and 3, an artificialheart valve leaflet 1000 according to an embodiment of the present invention has an open state and a closed state, wherein the artificialheart valve leaflet 1000 shown in fig. 1a is in the closed state, and the artificialheart valve leaflet 1000 shown in fig. 1b is in the open state.

Specifically, the artificialcardiac leaflet 1000 includes at least twoleaflets 1100 arranged in a ring shape, each of theleaflets 1100 includes amain body wall 1110 and aclosing wall 1120 that are sequentially connected in an axial direction, where themain body wall 1110 and theclosing wall 1120 are sequentially arranged from an inflow end to an outflow end of the artificial cardiac leaflet prosthesis, that is, the "axial direction" refers to a direction parallel to a blood flow direction after the artificialcardiac leaflet 1000 is implanted into a heart. The ring shape may have a regular shape such as a circle, a rectangle, a regular polygon, or other irregular shapes, and for convenience of understanding, a circle is illustrated in this embodiment, and thus, a direction perpendicular to the blood flow direction is a radial direction of the artificialheart valve leaflet 1000. In the following description, the artificial heart valve leaflet of the present embodiment is explained assuming that theleaflet 1100 is more than two and at least twoleaflets 1100 are arranged in a circular shape, but this should not be construed as limiting the present invention.

When the prostheticheart valve leaflet 1000 is in the open state, theclosing walls 1120 of theleaflets 1100 are separated from each other without overlapping. And when the prostheticheart valve leaflet 1000 is in the closed state, theclosing walls 1120 of theleaflets 1100 are brought closer together to at least partially overlap themain body walls 1110 of the leaflets to thereby cause circumferential closure of the prostheticheart valve leaflet 1000, while theclosing walls 1120 of anyadjacent leaflets 1100 are at least partially overlapped to cause axial closure of the prostheticheart valve leaflet 1000. It is understood that "overlap" herein refers to a state in which anyadjacent leaflets 1100 are superposed and attached to each other.

Further, when the prostheticheart valve leaflet 1000 is in the open state, themain body walls 1110 of anyadjacent leaflets 1100 partially overlap, so that when the prostheticheart valve leaflet 1000 is in the closed state, it can be ensured that it is reliably closed circumferentially. Preferably, when the prostheticheart valve leaflet 1000 is in the closed state, the prostheticheart valve leaflet 1000 forms a funnel-shaped structure, when theclosing walls 1120 of any twoadjacent leaflets 1000 at least partially overlap to close the tips of the funnel-shaped structure.

Fig. 3 shows the positional relationship of a part of theleaflet 1100 when the artificialheart valve leaflet 1000 is in the open state. More specifically in conjunction with fig. 3, the fourleaflets 1100 are arranged about a central axis and are circumferentially stacked, such that, when viewed from the direction from theclosure wall 1120 toward themain body wall 1110, the fourleaflets 1100 are identified as afirst leaflet 1100a, asecond leaflet 1100b, athird leaflet 1100c, and afourth leaflet 1100d, respectively, in a clockwise order. Thesecond leaflet 1100b is positioned outside thefirst leaflet 1100a during the opening or closing of the prostheticheart valve leaflet 1000, and a portion of thesecond leaflet 1100b always overlaps thefirst leaflet 1100 a; thethird leaflet 1100c is outside thesecond leaflet 1100b, and a portion of thethird leaflet 1100c always overlaps thesecond leaflet 1100 b; thefourth leaflet 1100d is located outside thethird leaflet 1100c, and a part of thefourth leaflet 1100d always overlaps thethird leaflet 1100c, and so on, until the ends of themain body walls 1110 of all theleaflets 1100 far from theclosing wall 1120 form a ring to form a complete artificialheart valve leaflet 1000. When the prostheticheart valve leaflet 1000 is contracted to the closed state, theclosing walls 1120 of theleaflets 1100 are close to each other and theclosing walls 1120 of theadjacent leaflets 1100 are partially overlapped until the prostheticheart valve leaflet 1000 forms a funnel-shaped structure with closed periphery and closed tip, at which time the overlapping area of themain body walls 1110 of theadjacent leaflets 1100 is larger than that of themain body walls 1110 of theadjacent leaflets 1100 in the open state.

In the embodiment of the present invention, on the one hand, when the artificialheart valve leaflet 1000 is in the open state, there is still a partial overlap between themain body walls 1110 of theadjacent leaflets 1100, so as to ensure that the adjacentmain body walls 1110 have a sufficient coaptation area when the artificialheart valve leaflet 1000 is in the closed state to ensure the closing effect of the artificialheart valve leaflet 1000 in the circumferential direction; on the other hand, when the artificialcardiac valve leaflet 1000 is in the closed state, because themain body wall 1110 has a certain thickness, the tip of the funnel-shaped structure formed by themain body wall 1110 has a small hole, and by providing theclosing wall 1120 on theleaflet 1100, theadjacent closing walls 1120 can block the small hole when being overlapped in sequence, and theclosing wall 1120 can also increase the closing height of the artificialcardiac valve leaflet 1000, further improve the closing performance of the artificialcardiac valve leaflet 1000 in the axial direction, so that the artificialcardiac valve leaflet 1000 can be completely closed, thereby effectively preventing blood from flowing back and avoiding generating a large trans-valve pressure difference. It should be understood that the "height" mentioned herein refers to a length in the axial direction of the artificialheart valve leaflet 1000.

Preferably, theleaflets 1100 form an arcuate configuration in the circumferential direction, and the overlapping portions of thebody walls 1110 can better conform when theleaflets 1100 are stacked and collapsed to the closed position to improve the closing effect.

As shown in fig. 6a, in practice, the artificialheart valve leaflet 1000 is implanted into the heart through thestent 2000. Thestent 2000 has aninflow end 2100 and anoutflow end 2200, wherein theinflow end 2100 refers to an inlet end of blood and theoutflow end 2200 refers to an outlet end of blood. The artificialheart valve leaflet 1000 is disposed on the inner side of thestent 2000, and one end of themain body wall 1110 of eachleaflet 1100, which is away from theclosing wall 1120, is connected to theinflow end 2100 of thestent 2000. Thestent 2000 used in embodiments of the present invention may be any of the existing stents.

Generally, the closed height of the prostheticheart valve leaflet 1000 is at least 3mm, and in order to ensure the closed height of the prostheticheart valve leaflet 1000, the height of the connection position of theclosing wall 1120 and themain body wall 1110 when the prostheticheart valve leaflet 1000 is in the closed state should be equivalent to the height of the stent annulus 2300. In other words, when the prostheticheart valve leaflet 1000 is in the closed state, the connection site of theclosing wall 1120 and themain body wall 1110 is the same or substantially the same as the position of the stent annulus in the axial direction of the prostheticheart valve leaflet 1000. In addition, the height of theclosing wall 1120 should be greater than 1mm, that is, the length of theclosing wall 1120 in the axial direction of the prostheticheart valve leaflet 1000 is greater than 1mm when the prostheticheart valve leaflet 1000 is in the closed state. In addition, the shape of theclosing wall 1120 is not strictly limited, and the planar expansion shape may be a triangle, a rectangle, or other shapes. It should also be noted that the stent annulus is the location of thestent 2000 corresponding to the annulus in the heart and is well known to those skilled in the art.

With continued reference to fig. 6a in conjunction with fig. 6b, when the prostheticheart valve leaflet 1000 expands from the closed state to the open state, theleaflets 1100 expand radially outward and close to thestent 2000 with risk of bending damage, for which thebody wall 1110 is provided in three parts. In detail, as shown in fig. 2, thebody wall 1110 includes anengaging wall 1111, acurved wall 1112, and an extendingwall 1113, which are connected in sequence. Wherein theengagement wall 1111 is adapted to be connected to theinflow end 2100 of thestent 2000, thecurved wall 1112 is made of an elastic material and has an arc shape in an axial section of the prostheticheart valve leaflet 1000, and the extension wall 1122 is connected to theclosing wall 1120. Because thecurved wall 1112 has elasticity and is an arc-shaped structure, theleaflet 1110 has stronger bending resistance when being expanded, the durability of theleaflet 1110 can be effectively improved, and the service life of the artificialheart valve leaflet 1000 is further prolonged. In addition, referring to fig. 3, in order to ensure the closing effect of the artificialheart valve leaflet 1000, when the artificialheart valve leaflet 1000 is in the open state, thecurved walls 1112 of theadjacent leaflets 1100 at least partially overlap, and theextension walls 1113 of theadjacent leaflets 1100 should also at least partially overlap.

With continued reference to fig. 2, theengagement wall 1111 of the leaflet is comparable in circumferential dimension to thecurved wall 1112, and both may be rectangular in planar development. The planar development shape of theextension wall 1113 may be trapezoidal. Of course, theleaflet 1100 shown in fig. 2 is only one specific shape and is not the only choice, for example, fig. 4a and 4b show the shapes of twoother leaflets 1100, wherein in theleaflet 1100 shown in fig. 4a the planar development of theextension wall 1113 is triangular, whereas in theleaflet 1100 shown in fig. 4b the planar development of theextension wall 1113 is triangular and the axial dimension of thecoaptation wall 1111 is smaller than the circumferential dimension of thecurved wall 1112. Further, it is to be understood that in thevarious leaflet 1100 configurations illustrated herein, theextension walls 1112 are each axially straight, and in fact, theextension walls 1112 can also be axially arcuate. That is, the shape of theleaflet 1100 is not particularly emphasized in the embodiments of the present invention, as long as it can satisfy that thecurved walls 1112 of theadjacent leaflets 1100 at least partially overlap and theextension walls 1113 of theadjacent leaflets 1100 also at least partially overlap (i.e., themain body walls 1110 of theadjacent leaflets 1100 partially overlap) when the artificialheart valve leaflet 1000 is in the open state.

In order to better achieve the closing effect of the prostheticheart valve leaflet 1000, the slopes of the respective portions of theleaflet 1100 may also be optimally designed. The slope here refers to an angle between each portion of theleaflet 1100 and a reference plane, which is an end surface of the joiningwall 1111 away from thecurved wall 1112. In detail, as shown in fig. 5, an included angle between the extension wall and the reference plane is β, an included angle between the closing wall and the reference plane is α, and α > β; more preferably, an angle between a tangent line at a connecting point of the engaging wall and the curved wall and the reference plane is θ, an angle between a tangent line at a connecting point of the curved wall and the extending wall and the reference plane is γ, and α > γ > β, γ < θ, and α ≦ 30 ° or more and ≦ 90 °, β ≦ 30 ° or more and ≦ 90 °, θ ≦ 60 ° or more and ≦ 90 °.

In addition, each of the existing artificial heart valve leaflets is similar to a natural heart valve (i.e., aortic valve, pulmonary valve, mitral valve, and tricuspid valve), and needs to be connected with papillary muscles after being implanted into the heart so that the contraction and expansion of the artificial heart valve leaflets are controlled by the heart. Specifically, the artificial heart valve leaflet expands with the contraction of the heart and closes with the relaxation of the heart, i.e., the existing artificial heart valve leaflet can only open and close passively under the condition of force. However, in actual use, the artificial cardiac valve leaflet is often not closed well along with the diastole of the heart due to the deviation of the implantation position of the artificial cardiac valve leaflet, so that light reflux or local reflux occurs, and the problem of incomplete closure of the artificial cardiac valve leaflet is caused. In view of this, when the artificialheart valve leaflet 1000 according to the embodiment of the present invention is in the open state, theleaflet 1100 is configured to be automatically repositioned after the external force is removed, so that the artificialheart valve leaflet 1000 is restored to the closed state. Specifically, theleaflet 1100 can be made of a material with an elastic modulus between 0.2GPa and 2.5GPa, such as Polyurethane (PU), Polyethylene (PE), etc.; alternatively, theleaflets 1100 can be made of a shape memory material, such as nitinol or the like. In this manner, the artificialheart valve leaflet 1000 is in the closed state when not subjected to an external force, and the artificialheart valve leaflet 1000 may not need to be connected to papillary muscles after being implanted into the heart. When the heart contracts, the blood flows and the artificialcardiac valve 1000 expands under the action of the blood flow force, and when the heart relaxes, the blood flow force disappears and the artificialcardiac valve 1000 automatically retracts to the closed state.

Further, embodiments of the present invention also provide a heart valve prosthesis, including: astent 2000 having opposing inflow and outflow ends 2100, 2200; and the artificialheart valve leaflet 1000 as described above, which is disposed on the inner surface of thestent 2000, and thebody wall 1110 is connected to theinflow end 2100. More specifically, theengagement wall 1111 of thebody wall 1110 is connected to theinflow end 2100.

As described above, thestent 2000 may be any one of existing stents, and in particular, thestent 2000 has a mesh shape and a cross-sectional shape corresponding to the artificialheart valve leaflet 1000, for example, thestent 2000 has a circular cross-section. Thestent 2000 may be made of a biocompatible plastic expandable material known in the art, such as medical stainless steel or cobalt-chromium alloy, or may be a self-expandable material such as nitinol. Thestent 2000 may be cut from tubing or braided from wire. Themain body wall 1110, specifically, thecoaptation wall 1111, of the artificialheart valve leaflet 1000 is fixed to theinflow end 2100 of thestent 2000 by suturing or other means so that the artificialheart valve leaflet 1000 can be implanted into the heart through thestent 2000.

The heart valve prosthesis may further include askirt 3000 coupled to theinflow end 2100 of thestent 2000. When the heart valve prosthesis is implanted in a heart to replace a native heart valve, particularly a mitral valve or a tricuspid valve, askirt 3000 is provided at theinflow end 2100 of thestent 2000 to prevent paravalvular leakage.

Theskirt 3000 may include aninner skirt 3100 and anouter skirt 3200 which are connected to each other, wherein theinner skirt 3100 is disposed on an inner side of thebracket 2000, theouter skirt 3200 is disposed on an outer side of thebracket 2000, and theinner skirt 3100 and theouter skirt 3200 may be integrated. Preferably, the edge of theouter skirt 3200 remote from theinner skirt 3100 is undulated to reduce the amount of material used. Theskirt 3000 may be made of a medical polymer material such as polyethylene terephthalate (PET), which is conventional in the art, and theskirt 3000 may be fixed to theframe 2000 by various methods such as sewing, heat-bonding, and gluing.

The detailed operation of the heart valve prosthesis will be described herein below by way of example in which the heart valve prosthesis is implanted in the heart to control blood flow between the right atrium and the right ventricle in place of the tricuspid valve.

First, the heart valve prosthesis is delivered to the working position and expanded to the working size using conventional methods, with theinflow end 2100 of thestent 2000 facing the right atrium and theoutflow end 2200 of thestent 2000 facing the right ventricle.

When the heart relaxes and blood is pumped from the right ventricle to the lungs, the artificialheart valve leaflet 1000 is in the closed state to prevent blood from flowing back to the right atrium. During this time, more blood enters the right atrium. Subsequently, the heart contracts, blood flows in the right atrium, and the artificialheart valve leaflet 1000 expands radially outward to the open state by the blood flow force, and the blood flows into the right ventricle. Thereafter, the heart relaxes, and the artificialcardiac leaflet 1000 automatically returns to the closed state due to the structure and material of theleaflet 1100 itself.

According to the artificialheart valve leaflet 1000 and the heart valve prosthesis in the embodiment of the invention, theclosed wall 1120 is arranged on theleaflet 1100, and theleaflet 1100 is arranged in a layer-by-layer overlapping manner to form the artificialheart valve leaflet 1000, so that the artificialheart valve leaflet 1000 has good closure performance, backflow can be effectively prevented, the possibility of forming a large trans-valve pressure difference is reduced, and the working effect of the artificialheart valve leaflet 1000 is improved. Further, by preparing theleaflet 1100 from an elastic material or a shape memory material having an elastic modulus greater than 0.2GPa, the prostheticheart valve leaflet 1000 can be automatically returned to the closed state, thereby avoiding the problem of regurgitation due to deviation in the implantation position.

Although the present invention is disclosed above, it is not limited thereto. Various modifications and alterations of this invention may be made by those skilled in the art without departing from the spirit and scope of this invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (14)

1. A prosthetic heart valve leaflet comprising at least two leaflets distributed in an annular shape, and each of the leaflets comprising a main body wall and a closing wall connected in an axial direction; wherein:

the artificial heart valve leaflet has a closed state and an open state;

the leaflets are configured such that when the prosthetic heart valve leaflet is in the open state, the closed walls of the leaflets separate;

the leaflets are further configured such that when the prosthetic heart valve leaflet is in the closed state, body walls of adjacent leaflets at least partially overlap to cause circumferential closure of the prosthetic heart valve leaflet while closure walls of adjacent leaflets at least partially overlap to cause axial closure of the prosthetic heart valve leaflet.

2. The prosthetic heart valve leaflet of claim 1, wherein the leaflets are further configured such that when the prosthetic heart valve leaflet is in the open state, body walls of adjacent leaflets at least partially overlap.

3. The prosthetic heart valve leaflet as claimed in claim 1 or 2, wherein the prosthetic heart valve leaflet has a funnel-shaped structure and the closing walls of adjacent leaflets at least partially overlap to close the tips of the funnel-shaped structure when the prosthetic heart valve leaflet is in the closed state.

4. The prosthetic heart valve leaflet of claim 1 or 2, wherein the leaflet is configured to be automatically repositioned after release of the external force to enable the prosthetic heart valve leaflet to return from the open state to the closed state.

5. The prosthetic heart valve leaflet of claim 4, wherein the leaflet has an elastic modulus of 0.2GPa to 2.5 GPa.

6. The prosthetic heart valve leaflet of claim 4, wherein the leaflet is made of a shape memory material.

7. The prosthetic heart valve leaflet as claimed in claim 2, wherein the main body wall includes a joining wall, a curved wall and an extending wall which are connected in this order in the axial direction; the curved wall is arc-shaped in the axial section of the artificial heart valve leaflet; the extension wall is connected with the closing wall;

when the artificial heart valve leaflet is in the open state, the curved walls of adjacent leaflets at least partially overlap and the extended walls of adjacent leaflets at least partially overlap.

8. The prosthetic heart valve leaflet as claimed in claim 7, wherein the end surface of the coaptation wall away from the curved wall is a reference plane, the angle between the extension wall and the reference plane is β, the angle between the closure wall and the reference plane is α, and α > β.

9. The prosthetic heart valve leaflet as claimed in claim 8, wherein an angle between a tangent line at a connection point of the coaptation wall and the curved wall and the reference plane is θ, an angle between a tangent line at a connection point of the curved wall and the extension wall and the reference plane is γ, and α > γ > β, γ < θ.

10. The artificial heart valve leaflet as claimed in claim 9, wherein α is 30 ° or more and 90 ° or less, β is 30 ° or more and 90 ° or less, γ is 30 ° or more and 90 ° or less, and θ is 60 ° or more and 90 ° or less.

11. A heart valve prosthesis, comprising:

a stent having opposing inflow and outflow ends; and

the prosthetic heart valve leaflet of any one of claims 1-10, disposed within the stent and the body wall is coupled to the stent.

12. The heart valve prosthesis of claim 11, wherein the body wall comprises a coaptation wall, a curved wall, and an extension wall sequentially connected in an axial direction, wherein the coaptation wall is connected to the inflow end of the stent.

13. The heart valve prosthesis of claim 11 or 12, wherein the body wall has a stent annulus position corresponding to an annulus of a heart, and wherein the attachment position of the body wall to the closure wall corresponds to the stent annulus position when the prosthetic heart valve leaflet is in the closed state.

14. The heart valve prosthesis of claim 11 or 12, further comprising a skirt comprising an inner skirt and an outer skirt connected to each other; the inner skirt is arranged on the inner side surface of the inflow end of the bracket; the outer skirt edge is arranged on the outer side surface of the inflow end of the support, and the edge of the outer skirt edge, which is far away from the inner skirt edge, is wavy.

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