An asymmetric bileaflet curved mechanical heart valve

Abstract

An asymmetric double-leaflet curved mechanical heart valve. The application relates to an improved artificial mechanical heart mitral valve, which is closer to the natural mitral valve in terms of blood flow dynamics, effectively reduces blood reflux, is highly reliable and is suitable for all postures. The valve comprises a valve ring, a large valve leaflet and a small valve leaflet, the large valve leaflet and the small valve leaflet are respectively upwardly convex curved surfaces, the convex top curve of the large valve leaflet is matched with the concave top curve of the small valve leaflet, and the convex ridge formed by the top curve after the two are in contact forms a one-way locking ridge line; when the one-way locking ridge line is formed, the position of the shaft center of the large valve leaflet hinge pin is consistent with the position of the center of gravity of the large valve leaflet, so that the large valve leaflet is in a state of gravity balance under the support of the large valve leaflet hinge pin. The application reduces the height of the valve ring, eliminates the influence of the high valve ring or the convex structure on blood flow, adjusts the structure of the two valve leaflets, forms a more human application, and adopts a gravity balance design concept for the valve leaflet. The overall design is exquisite, and the blood flow dynamics is good.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more particularly to an improvement on an artificial mechanical mitral valve structure. Technical Background

[0002] The primary function of heart valves is to ensure unidirectional blood flow through the cardiovascular system. Certain types of heart disease can be treated surgically by replacing dysfunctional heart valves with artificial ones. Currently, there are two main types of artificial heart valves: mechanical heart valves (MHVs) and bioprosthetic heart valves (BHVs). Of the mechanical and bioprosthetic valves currently used in surgery, mechanical valves account for approximately 70% of the global market, and in my country, they account for over 80%. This is mainly because bioprosthetic valves are prone to calcification and breakage, have a short lifespan, and thus a narrow age range of application.

[0003] Currently, the mechanical heart valves used in surgery are mainly bileaflet mechanical valves. Based on extensive clinical follow-up results in recent years, bileaflet mechanical heart valves have excellent hemodynamic performance and a low incidence of valve-related complications, making them the most widely used and preferred artificial valves in clinical practice. A bileaflet artificial mechanical valve consists of a valve frame, leaflets, and suture rings, with the design and fabrication of the valve frame and leaflets being the core components. The existing patent document "CN 109771099 A, A Mechanical Valve on an Artificial Ring for Mitral Valve Replacement" proposes a mechanical mitral valve solution to address the problems of traditional mechanical mitral valves, such as lack of deformability and obstruction of leaflet movement by subvalvular devices. However, its structure has three main problems. First, it requires a localized extension of the axial height of the valve annulus. An excessively high annulus increases blood flow resistance and viscous dissipation, leading to increased shear stress and prolonged action time. This not only increases the risk of blood cell damage but also reduces the distance blood travels within the ventricles, hindering blood flow from scouring the ventricle and significantly increasing intracardiac blood stasis. Second, due to the close proximity of the leaflet hinges, complex and unstable blood flow occurs locally. The high-speed blood flow through the leaflets results in significant shear stress at the leaflet hinges and subvalvular parts, which restricts leaflet movement to some extent. This is also related to thrombus formation, which can lead to leaflet dysfunction. The opening angle of the leaflet relies on the engagement of protrusions on both sides of the leaflet with the mounting grooves of the leaflet frame. During normal opening and closing, due to material or design reasons, the protrusions may collide and wear against the mounting grooves, potentially leading to leaflet detachment. Third, the gravitational factor of artificial leaflets is difficult to avoid in existing technologies, and the gravitational factor affects the working condition of the human body depending on whether it is standing or lying down.

[0004] Therefore, how to further optimize the structure of artificial mitral valves to reduce the many defects in existing technologies has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] To address the above-mentioned technical problems, this invention provides an asymmetric bileaflet mechanical heart valve with the aim of making its hemodynamic performance closer to that of a natural mitral valve, effectively reducing blood regurgitation, and achieving higher reliability and better adaptability to all posture conditions during long-term operation.

[0006] An asymmetric bileaf curved mechanical heart valve of the present invention includes a valve annulus and a large leaflet and a small leaflet respectively movably disposed within the valve annulus by a hinge pin. The large leaflet and the small leaflet are respectively upwardly convex curved surfaces. The large leaflet has a convex curved surface at the top edge of the large leaflet and a concave curved surface at the top edge of the small leaflet. The convex curved surface at the top edge of the large leaflet and the concave curved surface at the top edge of the small leaflet are adapted to each other, and the top curved ridge formed after the two come into contact forms a one-way locking ridge. The large leaflet is adapted to the inner cylindrical surface of the petal ring through the curved surface of its bottom edge. The small leaflet is adapted to the inner cylindrical surface of the petal annulus through the curved surface of the bottom edge of the small leaflet. The large petal has a large petal hinge pin. When forming the unidirectional locking ridge, the axial position of the large petal hinge pin coincides with the center of gravity of the large petal, so that the large petal is in a state of gravitational balance under the support of the large petal hinge pin.

[0007] Furthermore, the axis of the large leaf hinge pin is located at the middle of the large leaf, and when forming the one-way locking ridge, the area of ​​the top surface of the large leaf above the axis is smaller than the area below the axis.

[0008] Furthermore, the small leaflet has a small leaflet hinge pin. When forming the unidirectional locking ridge, the axial position of the small leaflet hinge pin coincides with the center of gravity position of the small leaflet, so that the small leaflet is in a state of gravitational balance under the support of the small leaflet hinge pin.

[0009] Furthermore, the upper part of the small leaflet is thicker and the lower part is thinner, and / or the axial position of the hinge pin of the small leaflet is shifted to the right.

[0010] Furthermore, the small leaflet hinge pin is provided with an elastic structure, so that the small leaflet can overcome its own gravity and maintain gravitational balance.

[0011] Furthermore, the upper part of the large leaflet is thicker and the lower part is thinner, and / or the axial position of the hinge pin of the large leaflet is shifted to the left.

[0012] Furthermore, the large leaflet hinge pin is provided with an elastic structure, which enables the large leaflet to overcome its own weight and maintain gravitational balance.

[0013] Furthermore, a flow guiding surface is formed on the surface of the top convex surface and / or bottom concave surface of the large and / or small leaflets.

[0014] Furthermore, a pair of upright connecting surfaces are provided inside the petal ring, and a hinge groove is formed on the connecting surfaces.

[0015] Furthermore, the height of the valve ring is 1 to 1.1 times the lateral projection height when the large and small valve leaflets form the unidirectional locking ridge.

[0016] This invention breaks through traditional concepts in the structural design of the mitral valve for the artificial mechanical heart, innovatively proposing a large and small curved leaflet structure with an asymmetrical design. Firstly, it effectively reduces the height of the valve annulus, eliminating the impact of an excessively high annulus or protruding structures on blood flow, thus facilitating the flushing of the ventricular wall and effectively eliminating intraventricular blood stasis. Secondly, adjustments to the curved structure of the two leaflets themselves and the position of the hinge fulcrum increase the distance between the two leaflet hinges while ensuring reliable connection, forming a three-channel flow pattern with two jets after flow. Furthermore, the asymmetrical structure allows the two jets to form a larger clockwise vortex, resulting in a more ergonomic design. Thirdly, the innovative gravity-balanced design of the leaflets adapts to both upright and lying positions, with the opening and closing of the leaflets entirely controlled by the internal and external pressure difference, eliminating the influence of the leaflet's own weight and avoiding different working conditions under different postures.

[0017] The asymmetric bileaf curved mechanical heart valve design proposed in this invention is ingenious, more rational, simple, and efficient in structure, and has good hemodynamic performance. It meets the design standards for heart valves, breaks the long-standing dependence on foreign technology, and seizes the high ground of "forming a clockwise vortex in the ventricle", which can meet the needs of users to the greatest extent. Attached Figure Description

[0018] Figure 1 This is a three-dimensional schematic diagram of the asymmetric bileaf curved mechanical heart valve of the present invention in the fully open state. Figure 2 This is a three-dimensional schematic diagram of the valve ring in this invention. Figure 3 This is a schematic diagram of the asymmetric bileaf curved mechanical heart valve of the present invention in the fully open state. Figure 4 yes Figure 3 Left view, Figure 5 yes Figure 3 Top view; Figure 6 This is a three-dimensional schematic diagram of the large leaflet in this invention. Figure 7This is a schematic diagram of the structure of the large leaflet in this invention. Figure 8 yes Figure 7 Left view, Figure 9 yes Figure 8 Sectional view of AA; Figure 10 This is a three-dimensional schematic diagram of the small leaflet in this invention. Figure 11 This is a schematic diagram of the small leaflet structure in this invention. Figure 12 yes Figure 11 Left view, Figure 13 yes Figure 11 The right view, Figure 14 yes Figure 13 BB section view, Figure 15 yes Figure 13 Top view; Figure 16 This is a three-dimensional schematic diagram of the asymmetric bileaf curved mechanical heart valve of the present invention in a fully closed state. Figure 1 , Figure 17 This is a three-dimensional schematic diagram of the asymmetric bileaf curved mechanical heart valve of the present invention in a fully closed state. Figure 2 , Figure 18 This is a schematic diagram of the asymmetric bileaf curved mechanical heart valve of the present invention in a fully closed state. Figure 19 yes Figure 18 CC section view, Figure 20 yes Figure 18 DD section view, Figure 21 This is a schematic diagram of an optimized implementation of the large leaflet in this invention; Figure 22 This is a schematic diagram illustrating the working principle of the invention when fully closed. Figure 23 This is a schematic diagram illustrating the working principle of the present invention when fully open; Figure 24 This invention relates to the distribution of blood flow velocity at different characteristic moments within a cardiac cycle. Figure 25 This invention relates to the vorticity at different characteristic moments in a cardiac cycle.

[0019] In the figure, 1 is the petal ring, 11 is the inner cylindrical surface, 12 is the connecting surface, and 121 is the hinge groove; 2 is the large leaflet, 21 is the large leaflet connecting mating surface, 211 is the large leaflet hinge pin, 22 is the large leaflet top edge convex curved surface, 23 is the large leaflet bottom edge curved surface, and 24 is the flow guiding surface. 3 is the leaflet, 31 is the connecting mating surface of the leaflet, 311 is the hinge pin of the leaflet, 32 is the concave curved surface of the top edge of the leaflet, and 33 is the curved surface of the bottom edge of the leaflet. 4 is a one-way locked ridge line; H represents the leaflet thickness, Ⅰ represents working channel one, Ⅱ represents working channel two, and Ⅲ represents working channel three. a is the left ventricle, b is the left atrium, c is the aorta, and c1 is the aortic valve. Figure 22 , 23 The dashed arrow indicates the direction of blood flow. Detailed Implementation

[0020] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0021] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual images. They should not be construed as limiting the scope of this patent. To better illustrate the embodiments of the present invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0022] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present 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, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0023] In the description of this invention, unless otherwise explicitly specified and limited, the term "connection" or similar designation indicating a connection between components should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] like Figure 1-21 This invention discloses an asymmetric bileaflet curved mechanical heart valve, comprising a valve annulus 1, and a large leaflet 2 and a small leaflet 3 respectively movably disposed within the valve annulus 1 via hinge pins. The large leaflet 2 and the small leaflet 3 are both upwardly convex curved surfaces. The large leaflet 2 has a convex curved surface 22 at its apex, and the small leaflet 3 has a concave curved surface 32 at its apex. The convex curved surface 22 at the apex of the large leaflet and the concave curved surface 32 at the apex of the small leaflet are adapted to each other, and the resulting top curved ridge after contact forms a one-way locking ridge line 4. It should be noted that the convex curved surface 22 at the apex of the large leaflet and the concave curved surface 32 at the apex of the small leaflet are the top edges of the large leaflet 2 and the small leaflet 3, and after contact, a "closed" position is formed in the middle. Figure 20 In the fully closed state, from Figure 20 It can be seen that in this state, the highest point formed after the two lobes fold together is the unidirectional locking ridge line 4.

[0025] The large leaflet 2 is adapted to the inner cylindrical surface 11 of the petal ring 1 through the curved surface 23 of the bottom edge of the large leaflet, and the small leaflet 3 is adapted to the inner cylindrical surface 11 of the petal ring 1 through the curved surface 33 of the bottom edge of the small leaflet, which can form a "closed" inner cylindrical surface of the petal ring 1.

[0026] The large leaflet 2 has a large leaflet hinge pin 211. When forming the unidirectional locking ridge line 4, the axial position of the large leaflet hinge pin 211 coincides with the center of gravity of the large leaflet 2, so that the large leaflet 2 is in a state of gravity balance under the support of the large leaflet hinge pin 211.

[0027] Regarding the gravity balance design of the large leaflet 2, the following two specific measures are taken: First, the design involves adjusting the counterweight and hinge position by adjusting the thickness H of the leaflet, such as making the upper part of the large leaflet 2 thicker and the lower part thinner, and / or shifting the axis position of the hinge pin 211 of the large leaflet to the left.

[0028] Secondly, the design of the hinge structure, such as the large leaf hinge pin 211 having an elastic structure, enables the large leaf 2 to overcome its own gravity and maintain gravitational balance.

[0029] The adjustment of the counterweight and hinge fulcrum position, as well as the elastic structure of the hinge pin and the treatment of the rear angle of the two leaflets, are conventional technical measures in this field and will not be elaborated upon in this case.

[0030] Furthermore, the axis of the hinge pin of the large leaflet 2 is located in the middle of the large leaflet 2. When forming the unidirectional locking ridge 4, the area of ​​the top surface of the large leaflet 2 above the axis is smaller than the area of ​​the part below the axis. The main purpose of this design is to ensure that when the pressure in the left atrium b is higher than the pressure in the left ventricle a, the large leaflet 2 generates a counterclockwise flipping torque to open the two leaflets; and to completely eliminate the influence of the leaflet's own gravity on the leaflet flipping action.

[0031] Furthermore, the leaflet 3 has a leaflet hinge pin 311. When forming the unidirectional locking ridge line 4, the axial position of the leaflet hinge pin 311 coincides with the center of gravity of the leaflet 3, so that the leaflet 3 is in a state of gravitational balance under the support of the leaflet hinge pin 311.

[0032] The gravity balance design of the small leaflet 3 is similar to the aforementioned design of the large leaflet 2, and also includes the following two specific measures: First, the upper part of the leaflet 3 is thicker and the lower part is thinner, and / or the axial position of the leaflet hinge pin 311 is shifted to the right.

[0033] Secondly, the small leaflet hinge pin 311 is equipped with an elastic structure, which enables the small leaflet 3 to overcome its own gravity and maintain gravitational balance.

[0034] Furthermore, a flow guiding surface 24 is formed on the convex and / or concave surfaces of the large leaflet 2 and / or small leaflet 3. Given the mitral valve technology proposed in this invention, personalized design of dimensions and details is still required for different individuals. The cross-sectional shape and size of the aforementioned valve annulus 1, large leaflet 2, and small leaflet 3 need to be designed according to the individual, and the curvature of the two leaflets also needs to be personalized according to the individual. For different receptors, the flow state of blood entering the left ventricle a also needs to be personalized. Therefore, this invention also proposes designing a flow guiding surface on the bottom or top surface of the two leaflets with a certain thickness. This can be a convex or concave flow guiding surface 24, which is more conducive to the design of blood flow characteristics.

[0035] Furthermore, a pair of upright connecting surfaces 12 are provided inside the petal ring 1, and a hinge groove 121 is formed on the connecting surfaces 12. To ensure the reliability of the flipping of the two petals, upright connecting surfaces 12 are symmetrically provided inside the petal ring 1. Correspondingly, a large petal connecting mating surface 21 and a small petal connecting mating surface 31 are provided on the large petal 2.

[0036] Furthermore, the height of the valve annulus 1 is 1 to 1.1 times the lateral projection height when the large leaflet 2 and the small leaflet 3 form the unidirectional locking ridge 4. This is because an excessively long valve annulus increases blood flow resistance and viscous dissipation, thus increasing the shear stress on the blood flow, prolonging its action time, and reducing the distance the blood travels within the ventricle. The above-mentioned technical measures of this invention can minimize blood flow resistance and overcome the above-mentioned drawbacks.

[0037] The following is in conjunction with the appendix Figure 22-25 Further explanation of the working mechanism of the present invention: like Figure 22As shown, in the present invention, the mitral valve is in a fully closed state. When the left ventricle a contracts, it squeezes the blood in the left ventricle a, increasing the pressure inside the left ventricle a, which is higher than the pressure inside the left atrium b. Under the asymmetric structure, regurgitation cannot reverse the opening of the two leaflets. At this time, the aortic valve c1 on the top left side opens, allowing blood to enter the aorta c.

[0038] like Figure 23 As shown, when the left ventricle a relaxes, blood flows from the left atrium b through the pressure difference to open the two leaflets. At this time, the aortic valve c1 closes.

[0039] The opening and closing of the two leaflets are due to the transvalvular pressure gradient between the left ventricle (a) and the left atrium (b), which controls the unidirectional flow of blood.

[0040] The effect of this invention on left ventricular blood flow patterns was demonstrated in an in vitro PIV experiment, and the results are as follows: Figure 24 All the data came from six characteristic moments of a cardiac cycle, which represent: (i) diastolic acceleration phase 0.074s, (ii) diastolic peak 0.128s, (iii) diastolic deceleration phase 0.175s, (iv) end of diastole 0.25s, (v) systolic acceleration phase 0.525s, and (vi) systolic peak 0.561s.

[0041] In a traditional bileaflet mechanical heart valve, the two leaflets divide the circular annulus into three openings during normal operation: a central opening and two lateral openings. Blood flowing through these three openings forms three jets. Yoganathan et al. combined these three jets with the vortices they generate, defining it as a three-jet pattern. While the improved bileaflet valve of this invention also divides the circular annulus into three openings (e.g., ... Figure 3 , 5 As shown, after the two leaflets open, they form working channels I, II, and III. Due to the small size of the small leaflet 3, working channels II and III in the middle position are connected, which causes the blood flow through the valve to form two jets. The velocity distribution is shown in the figure above.

[0042] During (i) the diastolic acceleration phase, the mitral valve opens rapidly. Before optimization, the jet ejected from the side holes of the bileaflet valve was significantly stronger than the jet ejected from the central hole. After optimization, the jets from the central and right side holes of the bileaflet valve merged into one, which was much stronger than the jet ejected from the left side hole. In both cases, after entering through the mitral valve inlet, the jets fanned out towards the left ventricular lateral wall and septal wall. After reaching (ii) the diastolic peak, the jet from the central hole of the bileaflet valve disappeared before optimization, and the three jets merged into two jets. In contrast, the jet from the left side of the bileaflet valve disappeared after optimization, and the merged jet from the central and right side holes was enhanced. Entering the (iii) diastolic deceleration phase, the two jets of the bileaflet valve before optimization merged into a central flow region after moving 20 to 40 mm, and their velocity decreased rapidly. The jet of the bileaflet valve after optimization maintained a certain flow velocity, and the isokinetic surface rapidly moved to the apex. At the end of diastole (iv), for the unoptimized bileaflet valve, the isokinetic surface emanating from the mitral valve dissipates before reaching the apex, resulting in a more uniform flow distribution than during acceleration. This is highly likely to create a flow stagnation zone (average velocity <5 mm / s) at the apex, and thrombus formation and deposition are directly related to this stagnation zone, as explained in Virchow's stagnation triad, endothelial injury, and hypercoagulable state. For the optimized bileaflet valve, the jet flows along the apical shape change direction, effectively flushing the local area at the apex before moving towards the outflow tract.

[0043] After the diastolic phase, the left ventricle enters the (v) systolic acceleration phase. Before the optimization of the bileaflet valve, blood flow from the center of the left ventricle towards the aorta. Because the isokinetic surface had dissipated in the previous moment, almost all the kinetic energy of the outflow was provided by the contraction of the left ventricle, resulting in a lower outflow velocity. Furthermore, the inflow and outflow of blood created a crossflow channel, as confirmed by previous in vivo studies. In contrast, after the optimization of the bileaflet valve, the isokinetic surface of the left ventricle moved towards the apex in the previous moment. Upon reaching the apex, it turned along the shape of the endocardial wall, aligning with the outflow direction. The outflow channel is a ring-shaped channel along the shape of the left ventricular wall. At this point, the outflow is a result of the combined effect of the remaining kinetic energy from left ventricular contraction and diastole, resulting in a higher outflow velocity. After reaching the (vi) systolic peak, the outflow velocity of the optimized bileaflet valve is higher and more uniformly distributed than that of the unoptimized bileaflet valve. Before and after optimization, the angle between the outflow jet and the normal of the outlet plane is different. Studies have shown that the direction of the jet scouring the aortic wall may be the main cause of damage to the aortic intima. Although there is little research on whether the high-speed jet scouring the aortic valve orifice will cause aortic valve lesions, it is worth considering from the perspective of the mechanism of action.

[0044] The vortex evolution of this invention within a complete cardiac cycle is as follows: Figure 25During the acceleration phase of diastole (i), the unoptimized double-leaf structure generates two jet-like structures through the two side holes, and these jet structures move faster. The optimized double-leaf structure generates two jet-like structures through the left hole and the combined middle and right holes, and these jet structures move relatively slowly. During the peak diastole phase (ii), for the unoptimized double-leaf structure, because the middle hole is restricted by the two moving leaflets, a countercurrent jet is formed in the narrow gap between the two leaflets when they open rapidly. Therefore, the jet-like structure in the middle hole appears late and does not form a vortex structure. For the optimized double-leaf structure, the combined area of ​​the central and right holes is much larger than that of the left hole. Therefore, the combined hole develops into the main jet-like structure, and due to the segmentation by the small leaflets, its streamlines deflect towards the partition wall and the outer wall, respectively, forming two vortex structures. After entering the diastolic deceleration phase, the two vortices of the unoptimized double-leaflet detach from the free shear layer of the jet-like structure, forming a high-velocity jet at the central aperture, creating a concentric coherent structure. The interaction between the two side-aperture jets generates two large-scale vortices: a clockwise vortex on the left and a counterclockwise vortex on the right. Since the velocity in the right channel is greater than that in the left channel, the right vortex is stronger than the left. In the optimized double-leaflet, the left vortex is stronger than the right. The counterclockwise vortex on the right gradually dissipates due to its proximity to the outer wall, while the clockwise vortex remains stably located in the center of the left ventricle. At the end of diastole (iv), the left vortex of the unoptimized double-leaflet dissipates, while the right vortex begins to diffuse and completely dissipates before reaching the apex. This flow structure is similar to the results of previous fluid dynamics simulations and experimental studies. The optimized double-leaflet retains only one clockwise vortex, which gradually expands at the apex. Based on in vivo studies, the vortex at the apex can prevent blood stasis and reduce the risk of thrombosis at the apex; the downstream flow field of the optimized double-leaflet clearly improves this.

[0045] Upon entering systole, during (v) the acceleration phase of systole and (vi) the peak of systole, almost all the vortex structures in the left ventricle before the installation of the optimized bileaflet valve dissipated, and blood flowed out of the aorta under the contraction of the ventricular wall. In contrast, the clockwise vortices of the optimized bileaflet valve, upon encountering the ventricular wall, turned and moved towards the outflow tract. Upon reaching the peak of systole, its streamlines were observed to concentrate from the center of the left ventricle towards the outflow tract, and almost entirely aligned with the outlet direction. Therefore, the work done by the left ventricle to pump the same volume of blood was reduced.

[0046] Studies have shown that the vortex pattern is an important indicator of cardiac condition, and the vortex patterns differ between healthy and pathological hearts. Blood flow influences the structure and arrangement of endothelial cells through membranous mechanical transducers; therefore, blood flow vortices can activate the remodeling / growth of ventricular wall cells through force transmission, thereby affecting changes in ventricular structure and size. The original bileaflet mechanical heart valve altered the physiological blood flow pattern and cardiac load conditions of the left ventricle, which could impact cardiac development. Therefore, the design and implantation of artificial valves should focus on the characteristics of the interaction between vortices and the ventricle, and between vortices and the vessel wall, as these characteristics provide unique physiological and mechanical information about cardiac diastolic function. This optimized bileaflet mechanical heart valve design takes this into account, constructing a large-scale clockwise vortex, making the evolution and development of the left ventricular vortex downstream of the mitral valve very similar to its physiological state, thus reducing the impact of changes in the left ventricular vortex pattern after valve replacement surgery.

[0047] It should be stated that the above-described specific embodiments are merely preferred embodiments of the present invention and the technical principles employed. Those skilled in the art should understand that various modifications, equivalent substitutions, and variations can be made to the present invention based on the technical content disclosed in this application. However, such variations, as long as they do not depart from the spirit of the present invention, should be within the protection scope of the present invention. Furthermore, some terminology used in this specification and claims is not limiting but merely for ease of description.

Claims

1. An asymmetric bileaflet curved mechanical heart valve, comprising a valve annulus, and a large leaflet and a small leaflet respectively movably disposed within the valve annulus via a hinge pin, characterized in that, The large and small petals are respectively upward convex curved surfaces. The large petal has a convex curved surface at the top edge of the large petal, and the small petal has a concave curved surface at the top edge of the small petal. The convex curved surface at the top edge of the large petal and the concave curved surface at the top edge of the small petal are adapted to each other, and the top curved ridge formed after the two come into contact forms a one-way locking ridge. The large leaflet is adapted to the inner cylindrical surface of the petal ring through the curved surface of its bottom edge. The small leaflet is adapted to the inner cylindrical surface of the petal annulus through the curved surface of the bottom edge of the small leaflet. The large petal has a large petal hinge pin. When the one-way locking ridge is formed, the axial position of the large petal hinge pin coincides with the center of gravity of the large petal, so that the large petal is in a state of gravity balance under the support of the large petal hinge pin. The small leaflet has a small leaflet hinge pin. When forming the unidirectional locking ridge line, the axial position of the small leaflet hinge pin coincides with the center of gravity of the small leaflet, so that the small leaflet is in a state of gravitational balance under the support of the small leaflet hinge pin.

2. The asymmetric bileaflet curved mechanical heart valve according to claim 1, characterized in that, The axis of the large leaf hinge pin is located in the middle of the large leaf. When forming the one-way locking ridge, the area of ​​the top surface of the large leaf above the axis is smaller than the area below the axis.

3. The asymmetric bileaflet curved mechanical heart valve according to claim 1, characterized in that, The upper part of the small leaflet is thicker than the lower part and / or the axial position of the hinge pin of the small leaflet is shifted to the right.

4. The asymmetric bileaflet curved mechanical heart valve according to claim 1, characterized in that, The small leaflet hinge pin has an elastic structure, which enables the small leaflet to overcome its own weight and maintain gravitational balance.

5. An asymmetric bileaflet curved mechanical heart valve according to claim 1, characterized in that, The upper part of the large leaflet is thicker than the lower part and / or the axial position of the hinge pin of the large leaflet is shifted to the left.

6. An asymmetric bileaflet curved mechanical heart valve according to claim 1, characterized in that, The large leaflet hinge pin has an elastic structure, which enables the large leaflet to overcome its own weight and maintain gravitational balance.

7. An asymmetric bileaflet curved mechanical heart valve according to claim 1, characterized in that, A flow guiding surface is formed on the surface of the top convex surface and / or bottom concave surface of the large and / or small petals.

8. An asymmetric bileaflet curved mechanical heart valve according to claim 1, characterized in that, A pair of upright connecting surfaces are provided inside the petal ring, and a hinge groove is formed on the connecting surface.

9. An asymmetric bileaflet curved mechanical heart valve according to claim 1, characterized in that, The height of the valve ring is 1 to 1.1 times the lateral projection height when the large and small valve leaflets form the unidirectional locking ridge.

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