Valve stent, valve prosthesis and valve prosthesis system

Abstract

The invention discloses a valve stent, a valve prosthesis and a valve prosthesis system. The valve stent comprises an outer stent, an inner stent and an outer stent, the inner bracket is at least partially arranged in the outer bracket; the connecting piece is connected between the outer stent and the inner stent and allows one of the outer stent and the inner stent to move within a preset distance relative to the other one of the outer stent and the inner stent after being subjected to external force, so that the interaction time of blood and the valve stent is prolonged. Therefore, mutual influence between the valve leaflet of the outer stent and the valve leaflet of the inner stent can be weakened or isolated, and action time between blood and the inner stent and action time between blood and the outer stent can be prolonged, so that influence of the valve stent on ventricular contractility can be reduced, and closing stability of the valve leaflet is improved. Meanwhile, the impact force of blood flow on the valve stent during cardiac contraction can be reduced, the fatigue resistance of the valve stent can be improved, and the service life of the valve stent can be prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of heart valves, and in particular to a valve stent, a valve prosthesis and a valve prosthesis system. Background Art

[0002] With the development of social economy and the aging of the population, the incidence of valvular heart disease has increased significantly. Taking the mitral valve as an example, the mitral valve is one of the four major heart valves, located between the left atrium and the left ventricle. Normally, the mitral valve closes and opens following the contraction and dilation of the heart, maintaining the unidirectional flow of blood from the left atrium to the left ventricle. When mitral valve insufficiency occurs, during heart contraction, a part of the blood flows back into the left atrium, resulting in mitral regurgitation. Mitral regurgitation causes an increase in left atrial pressure, leading to an increase in pulmonary venous pressure. At the same time, the diastolic volume load of the left ventricle increases, and the left ventricle expands. In the late stage, pulmonary hypertension and heart failure may even occur. Transcatheter mitral valve replacement and repair have the advantages of not requiring thoracotomy, less trauma, and rapid patient recovery, and have received extensive attention from experts and scholars. Transcatheter heart valve replacement has been rapidly developed and applied clinically. Through minimally invasive small-incision intervention, an artificial heart valve is implanted at the site of the native heart valve to replace the diseased valve and restore the normal heart valve function, which is increasingly recognized by doctors and patients.

[0003] Currently, taking the mitral valve prosthesis as an example, after the mitral valve prosthesis is implanted into the body (such as a double-layer valve prosthesis with an inner stent and an outer stent), when the left ventricle contracts, the valve leaflets close. Due to the action of blood pressure, the valve leaflets will be subjected to pressure based on the area size. This pressure will be borne by the inner stent and then transmitted to the outer stent, and finally borne by the left atrial wall. The blood impacts the valve leaflet prosthesis at a certain speed, resulting in a large impact force on the atrial wall. The valve prosthesis has poor anti-fatigue ability and a short lifespan. At the same time, when the native mitral valve is in ventricular diastole and systole, the saddle-shaped valve annulus will have a folding movement. When an existing mitral valve prosthesis is implanted, such as an integrated valve prosthesis (a structure with an integrated inner stent and outer stent), due to the rigid connection (a "hard" connection) between the inner and outer frames, similar to a single-layer stent, in order to ensure that the valve leaflets can close normally, the native valve annulus needs to be stretched into the shape of the outer stent, which will cause the loss of the native valve annulus movement and a decrease in ventricular contractility. In addition, the integrated inner and outer stent has different mechanical property requirements for the inner and outer frames. The inner and outer frames must maintain the same material and the same treatment process. For example, if the inner frame needs heat treatment, then the outer frame must also be heat-treated. Therefore, this hinders the way to obtain different mechanical properties of the inner and outer frames. Further, since the inner frame of the current valve prosthesis is completely wrapped by the outer frame, and usually the valve leaflets are sutured to the inner frame through a suture process, the suture operation can only be carried out in the limited space inside the outer frame, which makes the operation inconvenient.

[0004] Therefore, it has become an urgent problem to develop a device that can weaken or isolate the mutual influence between the outer stent and the inner stent leaflets, reduce the impact of the valve stent on the ventricular contraction ability, improve the stability of the valve leaflet closure, and at the same time reduce the impact force of blood flow on the valve stent during heart contraction. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. For this purpose, an object of the present invention is to provide a valve stent that can weaken or isolate the mutual influence between the outer stent and the inner stent leaflets, extend the interaction time between the blood and the inner and outer stents, reduce the impact of the valve stent on the ventricular contraction ability, improve the stability of the valve leaflet closure, reduce the impact force of blood flow on the valve stent during heart contraction, improve the fatigue resistance of the valve stent, and increase its service life.

[0006] The present invention further provides a valve prosthesis.

[0007] The present invention also provides a valve prosthesis system.

[0008] The valve stent according to an embodiment of the first aspect of the present invention includes: an outer stent; an inner stent, at least a part of which is disposed inside the outer stent; and a connecting member that connects between the outer stent and the inner stent and allows one of the outer stent and the inner stent to move relative to the other within a predetermined distance when the other is subjected to an external force.

[0009] Thus, the movement of one of the inner stent and the outer stent within a predetermined distance by the connecting member can weaken or isolate the mutual influence between the outer stent and the inner stent, reduce the interference of the outer stent on the opening and closing of the leaflets and the impact force of blood during heart contraction on the valve prosthesis, reduce the impact of the valve stent on the ventricular contraction ability, improve the stability of the valve leaflet closure, ensure the ventricular contraction ability, and increase the service life of the valve stent.

[0010] In some examples of the present invention, the inner stent and the outer stent are movably connected within the predetermined distance through a flexible connection; preferably, the structure of the outer stent is a spherical-like stent, and the main structure of the inner stent of the inner stent is cylindrical; preferably, the hardness of the material of the inner stent is higher than the hardness of the material of the outer stent, or the inner stent and the outer stent are processed by different processes so that the hardness of the inner stent is higher than the hardness of the outer stent, so that the inner stent and the outer stent have different mechanical properties.

[0011] In some examples of the present invention, after the valve stent is implanted at the target position, the connecting member allows the inner stent to move relative to the outer stent in the atrial direction by a predetermined distance under the action of an external force, so as to extend the interaction time between the blood and the valve stent and reduce the bearing force of the outer stent; preferably, the connection between the inner stent provided with the connecting member and the outer stent is used to contact the valve annulus.

[0012] In some examples of the present invention, the outer stent is provided with a first fixing portion, the inner stent is provided with a second fixing portion, and the connecting member is connected between the first fixing portion and the second fixing portion and allows one of the first fixing portion and the second fixing portion to move relative to the other of the first fixing portion and the second fixing portion within a predetermined distance; preferably, a first fixing hole is provided on the first fixing portion, a second fixing hole is provided on the second fixing portion, and the connecting member passes through the first fixing hole and the second fixing hole.

[0013] In some examples of the present invention, at least two first fixing holes are provided on the first fixing portion, at least two second fixing holes are provided on the second fixing portion, and at least two first fixing holes, at least two second fixing holes and at least two connecting members are provided in one-to-one correspondence; or at least two first fixing holes and at least two second fixing holes are in one-to-one correspondence and are penetrated by the same connecting member; preferably, there are a plurality of first fixing portions which are spaced apart in the circumferential direction of the outer stent, there are a plurality of second fixing portions which are spaced apart in the circumferential direction of the inner stent, there are a plurality of connecting members, the plurality of first fixing portions and the plurality of second fixing portions are provided in one-to-one correspondence and correspond to at least one connecting member, and the first fixing portion extends along the axial direction of the valve stent for docking with the second fixing portion.

[0014] In some examples of the present invention, the inner stent and the outer stent are separately provided, and the connecting member is a flexible connecting component; preferably, the flexible connecting component is a flexible wire, a buffer gasket made of an elastic material, or an elastic layer between the first fixing portion of the outer stent and the second fixing portion of the inner stent.

[0015] In some examples of the present invention, the inner stent includes: an inner stent body; a mounting arm, one end of the mounting arm is connected to the inner stent body, and the other end of the mounting arm extends to the first fixing portion and is configured as the second fixing portion; preferably, the mounting arm includes: a first mounting section, the first mounting section extends radially outward along the inner stent body, and one end of the first mounting section is connected to the inner stent body; a second mounting section, the second mounting section is connected to the other end of the first mounting section and is bent relative to the first mounting section, and one end of the second mounting section close to the first fixing portion is configured as the second fixing portion; preferably, at least one of the first mounting section and the second mounting section is provided with a force buffering structure; preferably, the force buffering structure is a Z-shaped strut, an S-shaped strut, an inclined rod, a spring or a buffer rod made of an elastic material; or, the buffering performance of the material of the force buffering structure is higher than the buffering performance of the materials of the first mounting section and the second mounting section.

[0016] In some examples of the present invention, at least one of the first mounting section and the second mounting section includes: a first straight section; a second straight section, the second straight section is located on the extension line of the first straight section; a bending section, the bending section is bent and connected between the first straight section and the second straight section, and the bending section constitutes the force buffering structure; preferably, there are at least two bending sections, and at least two bending sections are sequentially connected between the first straight section and the second straight section, and the bending directions of adjacent two bending sections are opposite.

[0017] The valve prosthesis according to the second aspect embodiment of the present invention includes: the above-mentioned valve stent; a skirt, the skirt is arranged on the outer stent and the inner stent; valve leaflets, the valve leaflets are arranged on the inner stent; the skirt includes: an inner skirt and an outer skirt, and the inner skirt and the outer skirt are respectively connected to the inner stent and the outer stent.

[0018] The valve prosthesis system according to the third aspect embodiment of the present invention includes: the above-mentioned valve prosthesis and a delivery system; when the valve prosthesis is first assembled to the delivery system through the bottom of the valve stent, the second fixing portion of the inner stent is located outside the first fixing portion of the outer stent; when the valve prosthesis is first assembled to the delivery system through the top of the valve stent, the first fixing portion of the outer stent is located outside the second fixing portion of the inner stent.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be understood through the practice of the present invention. Description of the Drawings

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of embodiments in conjunction with the accompanying drawings, where:

[0021] Figure 1 is a schematic structural view of a valve stent according to an embodiment of the present invention;

[0022] Figure 2 is a schematic structural view of an outer stent according to an embodiment of the present invention;

[0023] Figure 3 is Figure 2 an enlarged view of region A in

[0024] Figure 4 is a schematic structural view of an inner stent according to an embodiment of the present invention;

[0025] Figure 5 is Figure 4 an enlarged view of region B in

[0026] Figure 6 is a top view of an inner stent according to an embodiment of the present invention;

[0027] Figure 7 is a schematic structural view of a valve prosthesis according to an embodiment of the present invention;

[0028] Figure 8 is Figure 7 an enlarged view of region C in

[0029] Figure 9 is a schematic structural view of a force buffering structure provided between an outer stent and an inner stent according to an embodiment of the present invention;

[0030] Figure 10 is Figure 9 an enlarged view of region D in

[0031] Figure 11 is a schematic structural view of a skirt according to an embodiment of the present invention;

[0032] Figure 12 is a schematic structural view of a valve leaflet according to an embodiment of the present invention;

[0033] Figure 13 is a schematic structural view of a valve leaflet in an unfolded state according to an embodiment of the present invention;

[0034] Figure 14 is a schematic structural view of a separation position between an outer stent and an inner stent located at the upper part according to an embodiment of the present invention;

[0035] Figure 15 is a schematic structural view of a separation position between an outer stent and an inner stent located at the middle part according to an embodiment of the present invention.

[0036] Reference numerals:

[0037] 100, valve stent;

[0038] 10, outer stent; 11, first fixing part; 12, first fixing hole;

[0039] 20, inner stent; 21, second fixing part; 22, second fixing hole; 23, inner stent body; 24, mounting arm; 241, first mounting section; 242, second mounting section; 243, first straight section; 244, second straight section; 245, bending section;

[0040] 25, force buffering structure;

[0041] 30, connecting piece;

[0042] 40, skirt; 41, inner skirt; 42, outer skirt; 43, suture;

[0043] 50, valve leaflet; 51, first valve leaflet; 52, second valve leaflet; 53, third valve leaflet;

[0044] 60, valve prosthesis. Detailed implementation manners

[0045] The embodiments of the present invention will be described in detail below. The embodiments described with reference to the drawings are exemplary.

[0046] Next, reference is made to Figures 1 - 15 Describe the valve stent 100 according to the embodiments of the present invention.

[0047] As Figure 1As shown in the figure, the valve stent 100 according to the embodiment of the first aspect of the present invention includes: an outer stent 10, an inner stent 20, and a connecting member 30. The inner stent 20 is at least partially disposed within the outer stent 10. The outer stent 10 is configured to be attached to the atrial wall, and the inner stent 20 is configured to provide an attachment position for a valve leaflet, which together with the inner and outer skirts attached to the outer surface of the periphery of a valve prosthesis 60 forms a one-way channel. A part of the structure of the outer stent 10 or the connection between the inner stent 20 and the outer stent 10 is configured to contact the valve annulus. The connecting member 30 is connected between the outer stent 10 and the inner stent 20, and the connecting member 30 allows one of the outer stent 10 and the inner stent 20 to move relative to the other within a predetermined distance after being subjected to an external force, so as to extend the interaction time between the blood and the valve stent 100. According to the momentum theorem, the force borne by the valve stent 100 is, on the one hand, related to the change in the momentum of the blood acting on the valve leaflet; on the other hand, it is related to the time taken for the change in blood momentum. If the time for the blood velocity to decrease is doubled, the force borne by the outer stent 10 is reduced to half of the original. In this way, the impact force of the blood on the inner stent 20 can be reduced. During ventricular systole, the blood moving towards the valve annulus will contact the prosthetic valve leaflet at a certain speed and then its speed becomes zero or reverses. According to the relationship between displacement and time, under the premise of a certain initial velocity, the larger the displacement, the longer the time. The small relative movement between the inner stent 20 and the outer stent 10 actually extends the displacement of the blood movement. According to the momentum theorem, extending the interaction time between the blood and the inner stent 20 and the outer stent 10 can effectively reduce the impact pressure of the blood on the valve stent 100.

[0048] Furthermore, since the outer stent and the inner stent in the traditional valve stent are of an integral structure and the strength of the inner stent and the outer stent is relatively high, the impact force between the inner stent and the outer stent is relatively large. However, in this valve stent 100, the outer stent 10 and the inner stent 20 are separately provided and are connected by the connecting member 30, which can extend the action time of the force between the outer stent 10 and the inner stent 20. In this way, the forces borne by the outer stent 10 and the inner stent 20 are relatively small, and thus the strain is also relatively small, so that the outer stent 10 and the inner stent 20 can be more stable.

[0049] Therefore, the movement of one of the inner stent 20 and the outer stent 10 within a predetermined distance by the connecting member 30 can weaken or isolate the mutual influence between the outer stent 10 and the inner stent 20, can reduce the interference of the outer stent 10 on the opening and closing of the valve leaflet and the impact force of the blood on the valve prosthesis during cardiac systole, reduce the influence of the valve stent 100 on the ventricular systolic ability, improve the stability of the valve leaflet closure, ensure the ventricular systolic ability, and can also improve the anti-fatigue ability of the valve stent 100 and its service life.

[0050] According to some embodiments of the present invention, the inner stent 20 and the outer stent 10 are movably connected within a predetermined distance through a flexible connection.

[0051] Among them, the inner stent 20 and the outer stent 10 are movably connected within a predetermined distance through a flexible connection. Since the connecting member 30 allows one of the outer stent 10 and the inner stent 20 to be acted on by an external force, due to the flexible connection, there is a buffering effect between the inner stent and the outer stent. The other of the outer stent 10 and the inner stent 20 moves within a predetermined distance. For example, when the outer stent 10 is stressed, the outer stent 10 first transmits the force to the connecting member 30. The connecting member 30 will deform during the stress process, and the impact force can be attenuated. Then the connecting member 30 transmits the remaining force to the inner stent 20, and the inner stent 20 moves relative to the outer stent 10 within a predetermined distance, which can further reduce the impact force. In this way, the influence between the outer stent 10 and the inner stent 20 can be reduced. Therefore, the valve stent 100 can reduce the influence of the interaction force between the outer stent 10 and the inner stent 20, and can also extend the interaction time between the blood and the inner stent 20 and the outer stent 10, thereby effectively reducing the impact force of the blood on the valve stent 100, improving the anti-fatigue ability of the valve stent 100, and also improving its service life.

[0052] According to some embodiments of the present invention, after the valve stent 100 is implanted at the target position, the connecting member 30 allows the inner stent 20 to move relative to the outer stent 10 in the atrial direction within a predetermined distance when acted on by an external force, so as to extend the interaction time between the blood and the valve stent 100 and reduce the bearing force of the outer stent 10.

[0053] Among them, after the valve stent 100 is implanted at the target position, the connecting member 30 allows the inner stent 20 to move relative to the outer stent 10 in the atrial direction within a predetermined distance when acted on by an external force, so as to extend the interaction time between the blood and the valve stent 100 and reduce the bearing force of the outer stent 10. Specifically, when the heart contracts and the blood impacts the valve leaflets, the inner stent 20 can move a very small distance relative to the outer stent 10 in the atrial direction. The inner stent 20 and the outer stent 10 adopt a flexible connection method, for example, so that the connection between the inner stent 20 and the outer stent 10 can move relative to each other, delaying the time when the blood rate decreases.

[0054] According to some embodiments of the present invention, the connection between the inner stent 20 and the outer stent 10 provided with the connecting member 30 is used to contact the valve annulus.

[0055] Wherein, at the connection between the inner stent 20 and the outer stent 10, the part where the connecting member 30 is provided is used to contact the valve annulus. In this way, the valve annulus can provide a relative reaction force for the connection between the inner stent 20 and the outer stent 10. For example, when the blood flow flushes, the inner stent 20 has a component force outward, and the valve annulus can provide a reaction force to ensure that the connection between the inner stent 20 and the outer stent 10 will not cause connection fatigue due to excessive force. For example, the connection between the inner stent 20 and the outer stent 10 is connected by a flexible wire, which will not cause fatigue of the flexible wire, thereby improving its service life. At the same time, the connection between the inner stent 20 and the outer stent 10 is located at the position of the valve annulus, and such a process is relatively easy to implement.

[0056] Preferably, the inner stent 20 and the outer stent 10 are separately provided. More preferably, the hardness of the material of the inner stent 20 is higher than the hardness of the material of the outer stent 10, or the inner stent 20 and the outer stent 10 adopt different processes so that the hardness of the inner stent 20 is higher than the hardness of the outer stent 10, so that the inner stent 20 and the outer stent 10 have different mechanical properties, and further enable the valve stent 100 to better adhere to the inner wall of the atrium and the valve annulus, and can more freely adjust the mechanical properties of the inner stent 20 and the outer stent 10 to adapt to the left atrial anatomical structures of different patients. Thus, compared with the valve stent in which the outer stent and the inner stent of the traditional valve stent are integrated, the valve stent has different mechanical property requirements for the inner stent and the outer stent. In the integrated valve stent, the inner stent and the outer stent must maintain the same material and the same treatment process. For example, both the inner stent and the outer stent need to be heat-treated. Therefore, this hinders the way to obtain different mechanical properties of the inner stent and the outer stent.

[0057] According to some embodiments of the present invention, as Figure 1 shown, the outer stent 10 is provided with a first fixing portion 11, the inner stent 20 is provided with a second fixing portion 21, the connecting member 30 is connected between the first fixing portion 11 and the second fixing portion 21, and the connecting member 30 allows one of the first fixing portion 11 and the second fixing portion 21 to move relative to the other of the first fixing portion 11 and the second fixing portion 21 within a predetermined distance.

[0058] Wherein, the setting of the first fixing portion 11 on the outer stent 10 and the second fixing portion 21 on the inner stent 20 can facilitate the connection between the outer stent 10 and the inner stent 20. One end of the connecting member 30 is connected to the first fixing portion 11, and the other end of the connecting member 30 is connected to the second fixing portion 21. The first fixing portion 11 and the second fixing portion 21 can move within a predetermined distance. In this way, the connecting member 30 can not only play a role in connecting the first fixing portion 11 and the second fixing portion 21, but also reduce the pressure borne by the valve stent 100 by extending the action time between the blood and the first fixing portion 11 and the second fixing portion 21.

[0059] According to some embodiments of the present invention, as Figure 3 and Figure 5 shown, a first fixing hole 12 is provided on the first fixing part 11, and a second fixing hole 22 is provided on the second fixing part 21. The connecting member 30 is passed between the first fixing hole 12 and the second fixing hole 22.

[0060] Among them, the overall shapes of the first fixing part 11 and the second fixing part 21 are both in the shape of a lug. The first fixing part 11 is provided with a first fixing hole 12. Correspondingly, the second fixing part 21 is provided with a second fixing hole 22. In this way, it is convenient for the connecting member 30 to connect and fix the first fixing part 11 and the second fixing part 21.

[0061] According to specific embodiments of the present invention, as Figure 3 and Figure 5 shown, at least two first fixing holes 12 are provided on the first fixing part 11, and at least two second fixing holes 22 are provided on the second fixing part 21. At least two first fixing holes 12, at least two second fixing holes 22 and at least two connecting members 30 are arranged in one-to-one correspondence. Or at least two first fixing holes 12 and at least two second fixing holes 22 are in one-to-one correspondence, and at least two first fixing holes 12 and at least two second fixing holes 22 are passed through by the same connecting member 30.

[0062] Specifically, the first fixing part 11 may be provided with two first fixing holes 12. Correspondingly, the second fixing part 21 is also provided with two second fixing holes 22. In this way, the first fixing part 11 and the second fixing part 21 can be connected by two connecting members 30. When one of the two first fixing holes 12 is disconnected from the connecting member 30, or one of the two second fixing holes 22 is disconnected from the connecting member 30, the stability of the connection between the first fixing part 11 and the second fixing part 21 can be ensured, thereby preventing the first fixing part 11 and the second fixing part 21 from falling off.

[0063] Furthermore, the number of the first fixing holes 12, the second fixing holes 22 and the connecting members 30 can be set to be greater than two. The first fixing holes 12, the second fixing holes 22 and the connecting members 30 can be provided in multiple numbers. Each first fixing hole 12 is connected to its corresponding second fixing hole 22 by a connecting member 30. When one of the first fixing holes 12 or the second fixing holes 22 is disconnected from the connecting member 30, the other first fixing hole 12 or the second fixing hole 22 remains connected to the connecting member 30. In this way, the separation between the first fixing part 11 and the second fixing part 21 can be further avoided, so that the connection between the first fixing part 11 and the second fixing part 21 can be more stable and firm.

[0064] In addition, at least two first fixing holes 12 and at least two second fixing holes 22 are penetrated by the same connecting member 30. One connecting member 30 penetrates at least two first fixing holes 12 and at least two corresponding second fixing holes 22 at the same time. In this way, the first fixing portion 11 and the second fixing portion 21 are connected by one connecting member 30, which can improve the connection efficiency between the first fixing portion 11 and the second fixing portion 21, and thus can improve the manufacturing efficiency of the valve stent 100.

[0065] According to some embodiments of the present invention, as Figure 8 shown, the inner stent 20 and the outer stent 30 are separately arranged, and the connecting member 30 is a flexible connecting component.

[0066] Among them, the inner stent 20 and the outer stent 30 in the valve stent 100 are separately arranged, which is convenient for disassembly and connection. Moreover, the inner stent 20 and the outer stent 30 are flexibly connected by a flexible connecting component, which can help extend the action time of blood and the valve stent 100, thereby reducing the peak pressure borne by the valve stent 100 and improving the fatigue resistance of the valve stent 100.

[0067] According to some embodiments of the present invention, the flexible connecting component is a flexible wire, a buffer gasket made of an elastic material, or the first fixing portion 11 of the outer stent 30 and the second fixing portion 21 of the inner stent 20 have an elastic layer.

[0068] Among them, when the connecting member 30 between the first fixing portion 11 and the second fixing portion 21 is arranged as a flexible wire or a buffer gasket made of an elastic material, the flexible wire is a polyester resin (PET) structure and can be made into a long filament shape. The flexible wire has good mechanical properties, high impact strength, and good folding resistance. In this way, the connection strength between the first fixing portion 11 and the second fixing portion 21 can be improved, and the reliability of the relative movement between the first fixing portion 11 and the second fixing portion 21 can also be improved. When the first fixing portion 11 of the outer stent 30 and the second fixing portion 21 of the inner stent 20 have an elastic layer, relative movement can occur between the first fixing portion 11 and the second fixing portion 21 through elastic deformation.

[0069] In addition, the connecting member 30 is a flexible structure, which can ensure that relative movement can occur between the first fixing portion 11 and the second fixing portion 21, and the inner stent 20 moves a relatively small distance in the atrial direction relative to the outer stent 10. In this way, the time for the blood rate to decrease can be delayed. According to the momentum theorem, if the time for the blood rate to decrease is doubled, the force borne by the outer stent 10 is reduced to half of the original, thereby reducing the impact force on the outer stent 10.

[0070] According to some embodiments of the present invention, as Figure 4As shown, the inner stent 20 includes: an inner stent body 23 and a mounting arm 24. One end of the mounting arm 24 is connected to the inner stent body 23, and the other end of the mounting arm 24 extends to the first fixing portion 11, and the other end of the mounting arm 24 is configured as a second fixing portion 21.

[0071] Among them, the inner stent 20 is mainly composed of an inner stent body 23 and a mounting arm 24. The setting of the mounting arm 24 can not only facilitate the connection between the inner stent 20 and the outer stent 10, but also increase the moving space between the inner stent 20 and the outer stent 10. In this way, the acting time between the blood and the inner stent 20 and the outer stent 10 can be prolonged, thereby reducing the impact pressure of the blood on the valve stent 100.

[0072] Furthermore, the other end of the mounting arm 24 is configured as a second fixing portion 21, which can facilitate the connection between the second fixing portion 21 and the first fixing portion 11 of the outer stent 10, thereby improving the connection efficiency between the inner stent 20 and the outer stent 10.

[0073] According to a specific embodiment of the present invention, as Figure 4 and Figure 5 shown, the mounting arm 24 includes: a first mounting section 241 and a second mounting section 242. The first mounting section 241 extends radially outward along the inner stent body 23. One end of the first mounting section 241 is connected to the inner stent body 23. The second mounting section 242 is connected to the other end of the first mounting section 241, and the second mounting section 242 is bent relative to the first mounting section 241. One end of the second mounting section 242 close to the first fixing portion 11 is configured as a second fixing portion 21.

[0074] Specifically, the mounting arm 24 is mainly composed of a first mounting section 241 and a second mounting section 242. The first mounting section 241 extends radially outward along the inner stent body 23, which can increase the distance between the inner stent 20 and the outer stent 10. When the outer stent 10 is subjected to the impact force of the blood, the time for the impact force transmitted from the outer stent 10 to the inner stent 20 can be increased, which can prolong the displacement of the blood movement. According to the momentum theorem, the acting time between the blood and the inner stent 20 and the outer stent 10 can be prolonged, thereby reducing the impact pressure of the blood on the valve stent 100.

[0075] Among them, preferably, at least a part of the mounting arm 24 is arranged perpendicular to the axis of the inner stent 20. This can facilitate the dispersion of the force of blood scouring on the axis of the inner stent 20 to the mounting arm 24. Preferably, a part of the first mounting section 241 and the second mounting section 242 is arranged perpendicular to each other. More preferably, the mounting arm 24 can also be inclined, which can disperse the force of blood scouring on the axis of the inner stent 20, and can also reduce the pressure on the inner stent 20 in the radial direction, so as to maintain the relative stability of the shape and size of the inner stent 20, and can also prevent the inner stent 20 from axially jumping relative to the outer stent 10.

[0076] In addition, the second mounting section 242 is bent relative to the first mounting section 241, which can further increase the time of action between the blood and the second mounting section 242, thereby reducing the impact force of the blood on the second mounting section 242, and also facilitating the connection between the second fixing portion 21 of the second mounting section 242 and the first fixing portion 11.

[0077] According to some embodiments of the present invention, as Figure 1 and Figure 6 shown, at least one of the first mounting section 241 and the second mounting section 242 is provided with a force buffering structure 25. The inner stent 20 is provided with the force buffering structure 25, so that its radial stiffness is lower than that of the inner stent main body 23. The outer stent 10 can move along with the native annulus. When the outer stent 10 is squeezed by the annulus, the outer stent 10 preferentially deforms with the inner stent main body 23 to ensure the stability of the shape of the inner stent 20, and the leaflets on the inner stent 20 can still open and close normally, to a certain extent isolating the mutual influence between the outer stent 10 and the leaflets of the inner stent 20. This will maintain the movement of the native annulus, thereby reducing the influence of the valve stent 100 on the ventricular systolic ability and ensuring the stability of valve closure.

[0078] Among them, the force buffering structure 25 can be arranged on the first mounting section 241, or the force buffering structure 25 can be arranged on the second mounting section 242, or the force buffering structure 25 can be arranged on both the first mounting section 241 and the second mounting section 242. For example, the force buffering structure 25 is arranged on the first mounting section 241, and the force buffering structure 25 is in a Z shape. In this way, the radial stiffness of the bottom of the inner stent 20 is much lower than that of the inner stent main body 23. When the blood impacts the first mounting section 241, when the impact force is transmitted to the force buffering structure 25, since the force buffering structure 25 preferentially squeezes and deforms, the deformation can be avoided from occurring on the inner stent main body 23, thereby reducing the impact force on the inner stent main body 23, and also ensuring that the shape of the inner stent main body 23 is more stable, playing a role in protecting the inner stent main body 23.

[0079] According to some embodiments of the present invention, the force buffering structure 25 is a Z-shaped strut, an S-shaped strut, an inclined rod, a spring or a buffer rod made of an elastic material. Alternatively, the buffering performance of the material of the force buffering structure 25 is higher than that of the materials of the first mounting section 241 and the second mounting section 242.

[0080] Among them, the force buffering structure 25 can be set as at least one of an inclined rod, an S-shaped strut, a corrugated rod, a Z-shaped strut, a spring or a buffer rod made of an elastic material. In this way, the force buffering structure 25 can be set as one of an inclined rod, a corrugated rod, an S-shaped strut, a Z-shaped strut, a spring or a buffer rod made of an elastic material. The force buffering structure 25 can also be set as a combination of two or three of an inclined rod, a corrugated rod, an S-shaped strut, a Z-shaped strut, a spring or a buffer rod made of an elastic material. Among them, the inclined rod can be obliquely connected to the first mounting section 241 or the second mounting section 242 at a certain angle, so as to disperse the impact force of the received blood. The corrugated rod is arranged in a corrugated shape. In this way, the corrugated rod is composed of a plurality of inclined rods with different directions and inclination angles connected in sequence, and the impact force of the blood received by the corrugated rod can be dispersed in each direction, so as to further reduce the force received by the corrugated rod. The Z-shaped strut is a Z-shaped rod arranged on the horizontal plane perpendicular to the axis of the inner stent 20, which can increase the buffering distance, so as to reduce the impact force of the blood on the inner stent 20.

[0081] In addition, the force buffering structure 25 can also be a buffer rod made of an elastic material. By undergoing elastic deformation, the impact force of the blood can be reduced. The force buffering structure 25 can be selected according to the actual situation and has good adaptability. In this way, the radial stiffness of the bottom of the inner stent 20 is much lower than the stiffness of the inner stent body 23. When the valve annulus contracts and squeezes the valve stent 100 at the positions of the first fixing portion 11 and the second fixing portion 21, and the force is transmitted to the force buffering structure 25 of the inner stent 20, it preferentially undergoes extrusion deformation, so that the deformation of the inner stent 20 does not occur on the inner stent body 23. The force buffering structure 25 can provide different mechanical properties, so that the impact force of the blood on the force buffering structure 25 can be further attenuated, thereby avoiding the deformation of the inner stent body 23.

[0082] According to some embodiments of the present invention, as Figure 5 shown, at least one of the first mounting section 241 and the second mounting section 242 includes: a first straight section 243, a second straight section 244 and a bending section 245. The second straight section 244 is located on the extension line of the first straight section 243. The bending section 245 is bent and connected between the first straight section 243 and the second straight section 244, and the bending section 245 constitutes the force buffering structure.

[0083] In addition, the first installation section 241 can be composed of a first straight section 243, a second straight section 244, and a bending section 245, or the second installation section 242 can be composed of the first straight section 243, the second straight section 244, and the bending section 245. In this way, the distance between the inner stent body 23 and the outer stent 10 can be increased, so that the relative movement distance between the inner stent body 23 and the outer stent 10 can be increased, and the impact force of the blood can be gradually attenuated, thereby reducing the impact pressure on the valve stent 100. In addition, both the first installation section 241 and the second installation section 242 are composed of the first straight section 243, the second straight section 244, and the bending section 245. In this way, the relative movement distance between the inner stent body 23 and the outer stent 10 can be further increased, thereby further reducing the impact pressure on the valve stent 100.

[0084] According to some embodiments of the present invention, as Figure 1 and Figure 5 shown, there are at least two bending sections 245. The at least two bending sections 245 are sequentially connected between the first straight section 243 and the second straight section 244, and the bending directions of adjacent two bending sections 245 are opposite.

[0085] Among them, one bending section 245 is bent and connected to the first straight section 243, and the other bending section 245 is bent and connected to the second straight section 244. In this way, the transmission direction of the impact force can be changed, and the impact force transmitted to the inner stent body 23 can also be attenuated, thereby playing a role in protecting the inner stent 20 body.

[0086] According to some embodiments of the present invention, as Figures 2 - 5 shown, there are multiple first fixing parts 11, and the first fixing parts 11 are spaced apart in the circumferential direction of the outer stent 10. There are multiple second fixing parts 21, and the second fixing parts 21 are spaced apart in the circumferential direction of the inner stent 20. There are multiple connecting pieces 30. The multiple first fixing parts 11 and the multiple second fixing parts 21 are arranged in one-to-one correspondence, and at least one connecting piece 30 corresponds to the multiple first fixing parts 11 and the multiple second fixing parts 21. The first fixing parts 11 are arranged to extend along the axial direction of the valve stent 100 for docking with the second fixing parts 21.

[0087] Among them, the multiple first fixing parts 11 are spaced apart in the circumferential direction of the outer stent 10. Correspondingly, the multiple second fixing parts 21 are spaced apart in the circumferential direction of the inner stent 20. The multiple first fixing parts 11 and the multiple second fixing parts 21 are connected by the connecting pieces 30. In this way, the connection between the inner stent 20 and the outer stent 10 can be made more stable and firm.

[0088] In addition, there are at least one connecting member 30 corresponding to the multiple first fixing parts 11 and the multiple second fixing parts 21, which can prevent the separation between the inner stent 20 and the outer stent 10, thereby ensuring the stability of the connection between the multiple first fixing parts 11 and the multiple second fixing parts 21.

[0089] According to some embodiments of the present invention, the structure of the outer stent 10 is a spherical-like stent, and the structure of the inner stent body 23 of the inner stent 20 is cylindrical.

[0090] Among them, the spherical-like stent of the outer stent 10 is arranged to be adapted to the shape of the inner wall of the atrium, so that the outer stent 10 can be closely attached to the inner wall of the atrium.

[0091] According to some embodiments of the present invention, the hardness of the material of the inner stent 20 is higher than the hardness of the material of the outer stent 10, or the inner stent 20 and the outer stent 10 adopt different processes, so that the hardness of the inner stent 20 is higher than the hardness of the outer stent 10, thereby enabling different mechanical properties between the inner stent 20 and the outer stent 10. In this way, the mechanical properties of the inner stent 20 and the outer stent 10 can be adjusted more freely, which is beneficial to adapting to the left atrial anatomical structures of different patients.

[0092] The valve prosthesis 60 according to the second aspect embodiment of the present invention, as Figures 7 - 13 shown, includes: the valve stent 100, the skirt 40 and the valve leaf 50 of the above embodiments. The skirt 40 is arranged on the outer stent 10 and the inner stent 20, and the valve leaf 50 is arranged on the inner stent 20.

[0093] Among them, the skirt 40 is arranged on the outer support 10 and the inner support 20, and can seal the outer support 10 and the inner support 20 respectively. In addition, the leaflet 50 includes: a first leaflet 51, a second leaflet 52, and a third leaflet 53. The first leaflet 51, the second leaflet 52, and the third leaflet 53 are sutured to the inner side of the inner support body 23 through the suture line 43, and the first leaflet 51, the second leaflet 52, and the third leaflet 53 are evenly distributed in the circumferential direction of the inner support body 23, so that the first leaflet 51, the second leaflet 52, and the third leaflet 53 can be more evenly stressed on the inner support body 23, thereby ensuring the stability of the inner support body 23. The setting of the force buffering structure 25 of the inner support 20 of the valve support 100 can effectively reduce the deformation of the position of the leaflets of the inner support body 23 caused by the contraction of the valve ring, thereby ensuring the stability of the opening and closing of the leaflets of the valve prosthesis and maintaining the unidirectional conductivity of the unidirectional channel. Therefore, the separate setting of the inner support 20 and the outer support 10 makes the suturing of the leaflets 50 and the inner skirt 41 to the inner support 20 and the outer skirt 42 to the outer support 10 independent and non-interfering, so that the suturing process has more physical operation space, reduces the difficulty of the suturing process, and helps to improve the suturing efficiency. The position where the inner and outer frames are separated can be located at the upper / middle / lower part of the outer support 10, and the lower part is preferred in this embodiment. Figure 14 As shown, the separation position of the outer bracket 10 and the inner bracket 20 is located at the upper part, as shown in FIG. Figure 15 As shown, the separation position of the outer bracket 10 and the inner bracket 20 is located in the middle.

[0094] According to some embodiments of the present invention, Figures 7 - 13 As shown, the skirt 40 includes: an inner skirt 41 and an outer skirt 42. The inner skirt 41 and the outer skirt 42 are respectively connected to the inner bracket 20 and the outer bracket 10. The connecting member 30 is connected between the outer bracket 10 and the inner bracket 20 to connect the inner skirt 41 and the outer skirt 42.

[0095] Specifically, the outer skirt 42 can be provided on the inner circumference or outer circumference of the outer support 10, or on both the inner circumference and outer circumference of the outer support 10. The inner skirt 41 can be provided on the inner circumference or outer circumference of the inner support 20, or on both the inner circumference and outer circumference of the inner support 20. The inner support 20 and the leaflets 50 are installed and fixed by the inner skirt 41, and the inner support 20 can provide support for the leaflets 50 and the inner skirt 41. The inner skirt 41 can seal the inner support 20 in the circumferential direction, and the leaflets 50 are used to replace the native valve. The outer skirt 42 can seal the outer support 10 in the circumferential direction. The outer skirt 42 attached to the outer support 10 can make the valve prosthesis 60 in close contact with the atrial wall of the atrium, thereby preventing blood from flowing through the gap between the valve prosthesis 60 and the atrial wall of the atrium.

[0096] Furthermore, since the outer support 10 and the inner support 20 of the valve support 100 are detachably arranged, the inner skirt 41 can be sewed in the circumferential direction of the inner support 20 and the outer skirt 42 can be sewed in the circumferential direction of the outer support 10 simultaneously, and then the leaflet 50 is sewed on the inner support body 23, and then the inner support 20 and the outer support 10 are connected (for example, by flexible wires), and finally, the inner skirt 41 and the outer skirt 42 are sutured at the junction of the inner skirt 41 and the outer skirt 42. The position where the inner support 20 is separated from the outer support 10 can be located at the upper, middle or lower part of the outer support 10, which can be selected according to actual conditions. The inner skirt 41 and the outer skirt 42 form a suture line 43 at the junction, which can connect the skirt 40 into a whole, thereby reducing the process steps and difficulty of suturing, and improving the suturing efficiency of the valve prosthesis 60.

[0097] Moreover, since the outer support 10 and the inner support 20 of the valve stent 100 are detachably arranged, the inner support 20 and the outer support 10 can be made of different raw materials and manufacturing processes to give them different mechanical properties. For example, different raw materials can be used without changing the stent structure to achieve different mechanical property requirements for the inner support 20 and the outer support 10, thereby adapting to the atrial anatomical structure of different patients.

[0098] In addition, the valve prosthesis 60 is arranged between the left atrium and the left ventricle to replace the native mitral valve. When the left ventricle relaxes, the blood flows from the left atrium to the left ventricle. At this time, the leaflets 50 of the valve prosthesis 60 are opened, and blood can flow into the left ventricle through the opened leaflets 50. When the left ventricle contracts, blood flows from the left ventricle into the aorta, and the leaflets 50 of the valve prosthesis 60 are compressed and closed, thereby preventing blood from flowing back to the left atrium.

[0099] According to the third aspect of the present invention, the valve prosthesis system includes: the above-mentioned valve prosthesis 60 and a delivery system. When the valve prosthesis 60 is first assembled on the delivery system through the bottom of the valve stent 100, the second fixing portion 21 of the inner stent 20 is located on the outside of the first fixing portion 11 of the outer stent 10. When the valve prosthesis 60 is first assembled on the delivery system through the top of the valve stent 100, the first fixing portion 11 of the outer stent 10 is located on the outside of the second fixing portion 21 of the inner stent 20.

[0100] Among them, when the valve prosthesis 60 is connected to the bottom of the valve stent 100, the bottom of the valve stent 100, that is, the connection part where the valve prosthesis 60 is connected to the bottom of the valve stent 100, the second fixing part 21 of the inner stent 20 is located outside the first fixing part 11 of the outer stent 10, and when the inner stent 20 is subjected to the outward force of the blood flow, the first fixing part 11 of the outer stent 10 provides an outward pulling force to the second fixing part 21 of the inner stent 20 through the connecting piece. When the valve prosthesis 60 is connected to the top of the valve stent 100, that is, the connection part where the valve prosthesis 60 is connected to the top of the valve stent 100, the first fixing part 11 of the outer stent 10 is located outside the second fixing part 21 of the inner stent 20, and when the inner stent 20 is subjected to the outward force of the blood flow, the second fixing part 21 of the inner stent 20 provides an outward pulling force to the first fixing part 11 of the outer stent 10 through the connecting piece 30.

[0101] In the description of the present invention, it should be understood that the terms "center", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0102] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and purpose of the present invention, and the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A valve stent, characterized in that, Comprising: An outer stent; An inner stent, at least part of which is disposed within the outer stent; A connecting member that connects between the outer stent and the inner stent and allows one of the outer stent and the inner stent to move relative to the other of the outer stent and the inner stent within a predetermined distance when a force is applied, so as to extend the interaction time between blood and the valve stent.

2. The valve stent according to claim 1, characterized in that, The inner stent and the outer stent achieve movement within the predetermined distance through a flexible connection; Preferably, the structure of the outer stent is a spherical-like stent, and the main structure of the inner stent of the inner stent is cylindrical; Preferably, the hardness of the material of the inner stent is higher than the hardness of the material of the outer stent, or the inner stent and the outer stent adopt different processes, such that the hardness of the inner stent is higher than the hardness of the outer stent, so that the inner stent and the outer stent have different mechanical properties.

3. The valve stent according to claim 1, characterized in that, After the valve stent is implanted at the target position, the connecting member allows the inner stent to move relative to the outer stent within a predetermined distance towards the atrial direction when a force is applied, so as to extend the interaction time between blood and the valve stent and reduce the bearing force of the outer stent; Preferably, the connection between the inner stent provided with the connecting member and the outer stent is used to contact the valve annulus.

4. The valve stent according to claim 1, characterized in that, The outer stent is provided with a first fixing portion, the inner stent is provided with a second fixing portion, and the connecting member is connected between the first fixing portion and the second fixing portion and allows one of the first fixing portion and the second fixing portion to move relative to the other of the first fixing portion and the second fixing portion within a predetermined distance; Preferably, a first fixing hole is provided on the first fixing portion, a second fixing hole is provided on the second fixing portion, and the connecting member passes through between the first fixing hole and the second fixing hole.

5. The valve stent according to claim 4, characterized in that, At least two of the first fixing holes are provided on the first fixing portion, at least two of the second fixing holes are provided on the second fixing portion, and at least two of the first fixing holes, at least two of the second fixing holes and at least two of the connecting members are provided in one-to-one correspondence; or At least two of the first fixing holes and at least two of the second fixing holes are in one-to-one correspondence and are passed through by the same connecting member; Preferably, there are a plurality of the first fixing portions which are spaced apart in the circumferential direction of the outer stent, there are a plurality of the second fixing portions which are spaced apart in the circumferential direction of the inner stent, there are a plurality of the connecting members, the plurality of the first fixing portions and the plurality of the second fixing portions are provided in one-to-one correspondence and correspond to at least one of the connecting members, and the first fixing portion extends along the axial direction of the valve stent for docking with the second fixing portion.

6. The valve stent according to claim 1, characterized in that The inner stent and the outer stent are separately provided, and the connecting member is a flexible connecting component; Preferably, the flexible connecting component is a flexible wire, a buffer gasket made of an elastic material, or an elastic layer between the first fixing portion of the outer stent and the second fixing portion of the inner stent.

7. The valve stent according to claim 6, wherein, The inner stent includes: An inner stent main body; An installation arm, one end of the installation arm is connected to the inner stent body, and the other end of the installation arm extends to the first fixing part and is configured as the second fixing part; Preferably, the installation arm includes: a first installation section, the first installation section extends radially outward along the inner stent body, and one end of the first installation section is connected to the inner stent body; A second installation section, the second installation section is connected to the other end of the first installation section and is bent relative to the first installation section, and one end of the second installation section close to the first fixing part is configured as the second fixing part; Preferably, at least one of the first installation section and the second installation section is provided with a force buffering structure; Preferably, the force buffering structure is a Z-shaped strut, an S-shaped strut, an inclined rod, a spring or a buffer rod made of an elastic material; Alternatively, the buffering performance of the material of the force buffering structure is higher than the buffering performance of the materials of the first installation section and the second installation section.

8. The valve stent according to claim 7, characterized in that At least one of the first installation section and the second installation section includes: A first straight section; A second straight section, the second straight section is located on the extension line of the first straight section; A bending section, the bending section is bent and connected between the first straight section and the second straight section, and the bending section constitutes the force buffering structure; Preferably, there are at least two bending sections, and at least two bending sections are sequentially connected between the first straight section and the second straight section, and the bending directions of adjacent two bending sections are opposite.

9. A valve prosthesis, characterized in that, Including: The valve stent according to any one of claims 1-8; A skirt, the skirt is arranged on the outer stent and the inner stent; Valve leaflets, the valve leaflets are arranged on the inner stent; The skirt includes: an inner skirt and an outer skirt, and the inner skirt and the outer skirt are respectively connected to the inner stent and the outer stent.

10. A valve prosthesis system, characterized in that, Including: The valve prosthesis according to claim 9 and a delivery system; When the valve prosthesis is first assembled to the delivery system through the bottom of the valve stent, the second fixing part of the inner stent is located outside the first fixing part of the outer stent; When the valve prosthesis is first assembled to the delivery system through the top of the valve stent, the first fixing part of the outer stent is located outside the second fixing part of the inner stent.

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