A valve prosthesis with variable positioning members and its delivery system

Abstract

The present invention belongs to the field of medical devices, and particularly relates to a valve prosthesis with a variable positioning member and its delivery system, which includes a stent body, a positioning member, and an artificial valve. The artificial valve is connected to the stent body. The positioning member includes a positioning arm and a control member. One end of the control member is cooperatively connected to the positioning arm. The positioning arm has a fixed end and a free end. The fixed end is fixedly connected to the stent body. When the positioning member is in a restricted state, the control member axially stretches the positioning arm, causing the positioning arm to deform in the axial direction. When the positioning member is in a released state, the positioning arm axially returns to a preset shape. The positioning member in the present invention has a fixed end and a free end. During loading, the control member can be used to axially pull the positioning arm, causing the positioning arm to deform. The positioning member and the stent body will not overlap during loading, reducing the diameter of the loading sheath of its delivery system and greatly reducing the trauma to the patient.

Description

Technical field:

[0001] The invention belongs to the field of medical instruments, and in particular relates to a valve prosthesis with a variable positioning element and a delivery system thereof. Background technology:

[0002] Aortic valve stenosis is mainly caused by the sequelae of rheumatic fever, congenital aortic valve structural abnormalities or senile aortic valve calcification. Patients are asymptomatic during the compensatory period, while patients with severe aortic valve stenosis often experience fatigue, dyspnea (exertional or paroxysmal), angina pectoris, dizziness or syncope, and may even die suddenly.

[0003] Aortic regurgitation means that the aortic valve opens when the ventricle contracts, and the blood in the left ventricle enters the aorta and is ejected to the whole body. It closes when the ventricle relaxes, preventing the blood in the aorta from flowing back to the left ventricle. If aortic valve insufficiency occurs, the aortic valve cannot close tightly during diastole, causing blood to flow back from the aorta into the left ventricle.

[0004] In the treatment of aortic valve disease, surgical valve replacement is a traditional and effective treatment method. However, most patients with this disease are elderly and have multiple organ diseases. Their physical conditions make it difficult for them to undergo surgery, making them hopeless patients for clinical treatment. In addition, the cause of degenerative aortic valve disease is still unclear, and it is impossible to treat the cause, nor is there an effective way to curb its development, and drug treatment is ineffective. Ideal measures for the treatment of aortic valve disease should be able to both improve the patient's symptoms and prolong their life. Percutaneous aortic balloon valvuloplasty, which was carried out in the early years, was used to treat aortic valve stenosis, but both single-center data and multi-center registration data showed that its long-term effect was poor. In China, surgical valve replacement is still a major treatment option. In recent years, some scholars at home and abroad have carried out basic and clinical research on percutaneous aortic valve replacement and have made some breakthrough progress. It provides an effective treatment method for high-risk elderly patients with aortic valve degeneration who need surgical valve replacement. In 2002, Cribier et al. successfully performed transcatheter aortic valve replacement (TAVR). To date, more than 50,000 TAVR surgeries have been completed worldwide. Studies around the world have shown that this technology is safe and effective for patients who are unable to undergo surgical valve replacement or who are at high risk of surgical valve replacement. Although most patients who undergo TAVR surgery are high-risk patients, the 30-day survival rate after surgery is higher than 90%, and the hemodynamic indicators of patients after TAVR surgery are significantly improved.

[0005] However, at present, native aortic valve insufficiency is still listed as a contraindication for TAVR. The main reason is that the accurate positioning and precise release of the stent valve are the most critical technical points in TAVR surgery. There are openings of the left and right coronary arteries above the aortic valve, and the mitral valve is adjacent below the valve. If the positioning and release are inaccurate, fatal complications such as coronary artery occlusion or massive mitral regurgitation may occur. Traditional TAVR devices, whether SAPIEN or CoreValve, are mainly used for patients with severe aortic stenosis and are not suitable for patients with aortic valve regurgitation. In the prior art, there has been a certain consensus on the device design for patients with aortic valve regurgitation. For example, JenaValve and Acurate abroad, and J-Valve in China all adopt a structure similar to the native leaflet positioning piece to position the three sinuses of the aortic valve, which is beneficial to the accurate positioning and implantation of the stent. However, at present, the above devices still mostly use the transapical approach, which still causes relatively large trauma to the patient and cannot be considered a percutaneous implantation in the strict sense. In response to the problem of balancing the native leaflet positioning piece and the overly large sheath, domestic scholars and engineers have made some conceptual attempts.

[0006] Certain consensus has been reached. For example, JenaValve, Acurate abroad, and J-Valve in China all adopt a structure similar to the native leaflet positioning piece to position the three sinuses of the aortic valve, which is beneficial to the accurate positioning and implantation of the stent. However, at present, the above devices still mostly use the transapical approach, which still causes relatively large trauma to the patient and cannot be considered a percutaneous implantation in the strict sense. In response to the problem of balancing the native leaflet positioning piece and the overly large sheath, domestic scholars and engineers have made some conceptual attempts.

[0007] Patent CN2010155694.8 describes an artificial valve with a movably connected valve buckle, which includes a support frame that can be radially expanded between a compressed state and an expanded state. The support frame has an outer surface and defines a central hole around an axis along the inflow and outflow directions; a plurality of elastic leaflets connected to the support frame, which provide a one-way valve in the hole when the support frame is in the expanded state; and at least one valve buckle that is axially movably connected to the support frame so that the at least one valve buckle can move along the axis between a nested position and an engaged position. In the nested position, the at least one valve buckle is located at a position where it nests with the support frame at a suitable contact or adjacent to the native valve. In the engaged position, the at least one valve buckle is offset from the support frame. The disadvantages of this design are as follows: The valve buckle is connected by being movably connected to the support frame, which may cause the valve buckle to shift in position during movement and cannot ensure that the valve buckle can reach the originally set position for connection after moving towards the support frame; secondly, there is no effective fixing structure between the valve buckle and the support frame. After the valve prosthesis is implanted, the valve buckle may have relative displacement with respect to the support frame, reducing the stability of the support frame in the heart position and affecting the use of its valve.

[0008] Patent CN201620032889.6 provides a transcatheter aortic valve prosthesis device, which includes: a main stent; leaflets fixed to the inner side of the middle part of the main stent; a skirt fixed along the inner periphery of the main stent and fixed to the leaflets; wherein, the upper end of the main stent forms an upper flared structure in a three-lobe form; there are three upper circular connection claws at the upper end of the upper flared structure for loading the main stent; the bottom end of the main stent has a lower flared structure that expands outward to reduce paravalvular leakage; there are three lower circular connection claws at the lower end of the lower flared structure; the aortic valve prosthesis device further includes a positioning ring located on the lower side of the main stent, and the positioning ring includes three V-shaped or U-shaped arc segments, and the ends of each of the V-shaped or U-shaped arc segments are connected to each other to form a ring, and three positioning circular connection claws are formed on the ends; the lower circular connection claws and the corresponding positioning circular connection claws are respectively connected by flexible positioning lines. Although this design scheme greatly reduces the diameter of the valve prosthesis when it is loaded into the sheath, the lower circular connection claws and the corresponding positioning circular connection claws are respectively connected by flexible positioning lines. When releasing and positioning, due to the upward rush of blood, there is no effective limiting / fixing structure between the positioning circular connection claws and the lower circular connection claws, resulting in the positioning circular connection claws may be "washed away", resulting in ineffective and inaccurate positioning.

[0009] In summary, one of the defects of the above fixing method is that the connection position between the valve buckle and the support frame is not accurate enough during positioning and is prone to positional deviation. The second defect is that there is no effective limiting structure between the positioning member and the stent body, which can enable the positioning member to effectively resist the impact force of blood when released and be accurately released to the target position. Summary of the Invention:

[0010] The purpose of the present invention is to improve and make up for the defects of the prior art, and propose a valve prosthesis with a variable positioning member and its delivery system that can effectively solve the above problems. The technology of the present invention has the characteristics of accurate positioning, stable clamping, firm clamping, and reduced paravalvular leakage, and solves the problems that the positioning member of the prosthesis in the prior art cannot resist the impact force of blood when released and the release positioning is inaccurate.

[0011] The purpose of the present invention is achieved by the following technical solutions:

[0012] A valve prosthesis with a variable positioning member includes a stent body, a positioning member, and an artificial valve. The artificial valve is connected to the stent body. The positioning member includes a positioning arm and a control member. One end of the control member is cooperatively connected to the positioning arm. The positioning arm has a fixed end and a free end. The fixed end is fixedly connected to the stent body. When the control member pulls the positioning arm, the free end of the positioning arm moves along the height direction of the stent body. When the control member is released, the positioning arm gradually returns to a preset shape.

[0013] Another object of the present invention can also be further achieved by the following technical solutions:

[0014] In some embodiments, the number of the positioning members is three. After being released, the positioning members are located at the bottom of the natural aortic sinus of the patient. The positioning members provide a certain supporting force for the stent body in the heart, while ensuring that the stent body can be safely and accurately released / implanted into the target position, and preventing the stent body from being "washed away" by the blood in the heart.

[0015] In some embodiments, the positioning arm includes a holding section and an elastic deformation section. The holding section is located at the free end of the positioning arm, and the elastic deformation section is located between the holding section and the fixed end of the positioning arm.

[0016] In some embodiments, the elastic deformation section is flexible relative to the holding section. When the positioning member is converted from the restricted state to the released state, the elastic deformation section deforms until it returns to a preset shape.

[0017] In some embodiments, the control member includes a push-pull rod and a locking structure. One end of the push-pull rod is cooperatively connected with the positioning arm, and the locking structure is arranged at the other end of the push-pull rod.

[0018] In some preferred embodiments, the locking structure is a plurality of protrusions evenly and symmetrically arranged on the left and right sides of the push-pull rod.

[0019] In some preferred embodiments, the protrusions are made of a metal memory material (such as nitinol). After the positioning member is released in the heart, the positioning member drives its locking structure to return to a preset shape, so that the protrusions pass through the fixing holes and are fixed. At this time, the connection between the locking structure and the fixing holes is in a form similar to a "snap fastener".

[0020] In some embodiments, the stent body is provided with fixing holes corresponding to the locking structure. When the control member is released, the locking structure is cooperatively connected with the fixing holes.

[0021] In some preferred embodiments, the fixing holes are arranged at the distal end of the stent body, and the control member is inserted into the fixing holes. When the valve prosthesis is loaded into the sheath, the positioning member is in the restricted state, and the control member axially pulls the positioning arm, causing the positioning arm to deform, so that the positioning arm and the control member do not overlap, and the diameter of the sheath tube during valve loading can be greatly reduced.

[0022] In some embodiments, the control member is arranged in a "human" shape; the forked end of the control member is connected to the positioning arm, and the two connection points of the control member on the positioning arm are symmetrically arranged about the axis of the push-pull rod, which can ensure the stability of its connection structure and prevent path deviation.

[0023] In another embodiment, the control member is a wire or filament, and the control member is detachably connected to the positioning arm. When the control member is released, the control member is separated from the positioning arm, so that the positioning arm gradually returns to a preset shape.

[0024] In some preferred embodiments, the control member can be a single-strand wire or filament, or can be a multi-strand wire or filament. One end of the control member connected to the positioning arm is detachably connected. The purpose of such a design is to greatly reduce the implant and reduce the contact and irritation to the intracardiac tissue, which is beneficial to the postoperative recovery of the patient.

[0025] In some embodiments, the positioning arm is made of a shape memory material, and the preset shape of the positioning arm is a "U" shape, a "V" shape or a "W" shape.

[0026] In some embodiments, barbs are provided on the surface of the positioning arm, or the surface of the positioning arm is coated with a film. The barbs are made of a metal memory material. After the positioning arm returns to the preset shape, the barbs can increase the friction force on the intracardiac tissue, and can effectively avoid the situation that the stent body falls off in the heart.

[0027] In some embodiments, the surface of the stent body is coated with a film, and the film material includes a metal material, polytetrafluoroethylene, polyethylene, polypropylene, polyester or an animal-derived material.

[0028] The present invention can be realized by the following technical solutions:

[0029] A valve prosthesis system with variable positioning members, comprising a valve prosthesis with positioning members, a control handle, an outer sheath, and a controllable release device. The valve prosthesis with positioning members includes a stent body, an artificial valve cooperatively connected to the stent body, and a positioning member. The stent body is cooperatively connected to the controllable release device. The positioning member includes a positioning arm and a control member. One end of the control member is detachably connected to the positioning arm, and the other end of the control member is cooperatively connected to the control handle. The positioning arm has a fixed end and a free end. The fixed end is fixedly connected to the stent body. When the control handle is operated to axially pull the control member, the free end of the positioning arm moves along the height direction of the stent body, and the positioning arm is gradually retracted into the gap between the stent body and the outer sheath until the elastic adaptation zone does not overlap with the part of the stent where the artificial valve is located. At this time, the positioning arm is in a restricted state. When the control handle is operated in the reverse direction, the positioning arm gradually returns to a preset shape, and the positioning arm gradually extends out of the gap between the stent body and the outer sheath and returns to the preset shape. At this time, the positioning arm is in a released state. Before the stent body is completely detached from the controllable release device, the positioning arm can be repeatedly switched between its restricted state and released state. The controllable release device includes a distal release device and a proximal release device. The distal release device is located at the distal part of the valve prosthesis system. Before the distal part of the stent body is completely detached from the distal release device, the distal part of the stent body is arranged in a retracted state within the distal release device. The proximal release device is arranged within the outer sheath and is cooperatively and detachably connected to the proximal end of the stent body. Before the positioning member and the distal part of the stent body are completely released, the proximal part of the stent body is restricted from being released by the proximal release device.

[0030] Compared with the prior art, the advantages of the above technical solution are as follows:

[0031] 1. The positioning member in the present invention has a fixed end and a free end. The control member can be used to axially pull the positioning arm, causing the positioning arm to deform, so that the positioning member and the stent body do not overlap during loading, reducing the diameter of the loading sheath of its delivery system during loading, enabling a transvascular path replacement operation for the patient, greatly reducing the trauma to the patient, and being beneficial to the patient's postoperative recovery.

[0032] 2. Different from the prior art where the positioning arm reduces the diameter of the loading sheath by flipping, although the diameter of its loading sheath can be reduced, it is easy to scrape the inner wall tissue of the aorta during the release and flipping process, resulting in the positioning arm not being able to flip to the preset shape. The present invention adopts the method of axially pulling and deforming the positioning arm and axially restoring it to the preset shape, avoiding scraping the inner wall tissue of the aorta while reducing the diameter, and improving the success rate of positioning member release.

[0033] 3. The positioning member in the present invention has a fixed end permanently connected to the stent body, so that the positioning arm can reach the specified position according to the preset path regardless of axial stretching, deformation or restoration of the preset shape, avoiding the positioning member from being offset or misaligned on the path during this process, improving the accuracy of the positioning member when releasing the positioning, and improving the success rate of the operation;

[0034] 4. The control member in the present invention is provided with a push-pull rod and a locking structure. When the positioning member is in a released state, the locking structure is connected with the stent body in cooperation. There are multiple connection points between the positioning member and the stent body, which can increase the connection stability between the two and effectively resist the impact force of the blood flow in the heart. Secondly, the multi-dimensional connection method can prevent the positioning member from everting outward to the greatest extent, causing the valve prosthesis to fall off;

[0035] 5. The control member in the present invention is made of shape memory material and has rigidity, so that when the positioning member is in the released state, the control member is connected with the stent body to increase the supporting force of the positioning member and ensure the stability of the stent body in the heart;

[0036] 6. In some embodiments of the present invention, the control member is configured as a wire or a thread, and the control member and the positioning arm are detachably connected. When the positioning member is in a released state, the control member is separated from the positioning arm, so that the positioning arm returns to a preset shape. The advantage of such a design is that the control member can be withdrawn from the body, which greatly reduces the implant, reduces the contact and stimulation to the intracardiac tissue, and is beneficial to the patient's postoperative recovery. Description of the drawings:

[0037] Figures 1a - 1e is a schematic diagram of a heart valve prosthesis according to the present invention.

[0038] Figures 2a - 2b The figure is a schematic diagram of the process of the control member pulling the positioning arm in the natural state of the heart valve prosthesis, wherein Figure 2b for Figure 2a Schematic diagram of the side structure.

[0039] Figures 3a - 3c It is a schematic diagram of the process of the control member pulling the positioning arm of the heart valve prosthesis in the delivery system.

[0040] Figures 4a - 4g It is a schematic diagram of the releasing process of the heart valve prosthesis.

[0041] Figures 5a - 5d It is a schematic diagram of the structure when the positioning arm is in a "V" shape.

[0042] Figures 6a - 6d It is a schematic diagram of the structure when the positioning arm is in a "W" shape.

[0043] Figure 7Schematic structural diagram of another embodiment.

[0044] Figures 8a - 8c Schematic diagram of the process of the control member pulling the positioning arm of the heart valve prosthesis in the delivery system in another embodiment.

[0045] Figures 9a - 9d Schematic diagram of the release process of the heart valve prosthesis in another embodiment.

[0046] Figures 10a - 10h For the loading and release methods of two valve prosthesis positioning members in the prior art, where Figure 10c is Figure 10b Partial enlarged view of. Specific implementation manner:

[0047] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the following examples are given with reference to the accompanying drawings to further elaborate on the present invention in detail.

[0048] In the present invention, the distal end refers to the end of the valve prosthesis far from the apex of the heart, and the proximal end refers to the end of the valve prosthesis close to the apex of the heart. Specific Example 1:

[0050] When the heart valve prosthesis is used to treat aortic valve diseases, as Figures 1a - 1d shown, it includes a stent body 1, a positioning member 2 and an artificial valve 3. The artificial valve 3 is connected to the stent body 1. The positioning member 2 includes a positioning arm 21 and a control member 22. One end of the control member 22 is cooperatively connected to the positioning arm 21. The positioning arm 21 has a fixed end 211 and a free end 212. The fixed end 211 is fixedly connected to the stent body 1. When the control member 22 pulls the positioning arm 21, the free end 212 of the positioning arm 21 moves along the height direction of the stent body 1. When the positioning member 2 is in the released state, the positioning arm 21 returns to a preset shape (as Figure 2a shown); when the positioning member 2 is in the restricted state, the free end 212 of the positioning arm 21 does not overlap with the stent body 1, which can greatly reduce the diameter of the valve sheath for loading, realize a transvascular replacement operation for the patient, greatly reduce the trauma to the patient, and is beneficial to the postoperative recovery of the patient.

[0051] In this embodiment, the number of the positioning members 2 is 3. After being released, the positioning members 2 are at the bottom of the natural aortic sinus of the patient. The positioning members 2 provide a certain supporting force for the stent body 1 in the heart, while ensuring that the stent body 1 can be safely and accurately released / implanted into the target position, preventing the stent body 1 from being "washed away" by the blood in the heart.

[0052] In this embodiment, the positioning member 2 can also play a role in clamping the autologous valve leaf.

[0053] In some embodiments, the positioning arm 21 includes a retaining section 213 and an elastic deformation section 214, wherein the retaining section 213 is located at the free end 212 of the positioning arm 21, and the elastic deformation section 214 is located between the retaining section 213 and the fixed end 211 of the positioning arm 21 (e.g. Figure 1b as shown).

[0054] In some embodiments, the elastic deformation section 214 is flexible relative to the holding section 213. When the positioning member 2 is converted from the restricted state to the released state, the elastic deformation section 214 is deformed until it is restored to a preset shape. Since the elastic deformation section 214 is flexible relative to the holding section 213, during the recovery process, the control member 22 axially pushes the positioning arm 21, so that the elastic deformation section 214 is converted from the straightened state to a bent state close to a "U" shape until it is restored to the preset straightened state (such as Figure 1e As shown), and in this process, the push-pull direction of the control member 22 always remains axial, while reducing the eversion of the positioning arm 21 during the recovery process, thereby preventing it from scraping the patient's blood vessel wall; in contrast, as shown Figure 10a As shown in FIG. 10d (the arc and arrow in the figure indicate the movement trajectory of the positioning member 2 from the restricted state in the sheath to the released state), although the positioning member 2 in the prior art can also achieve the purpose of reducing the loading tube diameter by flipping, the positioning member 2 is very difficult to load, and the positioning member 2 needs to be folded before loading. There is also a risk of the positioning member 2 breaking when folding. At the same time, when the positioning member 2 is released, the flipping process will scrape the blood vessel wall tissue, resulting in difficulty in releasing it and damaging the blood vessel wall tissue. Moreover, the positioning member 2 cannot be recovered after being released, and the fault tolerance rate is small. Figure 10f As shown in FIG. 10h, the positioning member 2 in the prior art always overlaps with the stent during loading and release, resulting in a larger loading diameter, higher requirements for the access method, and failure to achieve true percutaneous implantation. The larger the wound diameter of the patient, the more unfavorable it is for the patient's postoperative recovery. Figure 2a and 2b As shown in the figure (front view of the valve prosthesis), when the positioning member 2 switches between the restricted state and the released state, a "rounded corner" is generated between the elastic deformation section 214 of the positioning member 2 and the stent body 1. Figure 2b As shown in the figure (side structural diagram of valve prosthesis), the "rounded corner" does not exist in the lateral direction; compared with the technical solution of the positioning member using flipping in the prior art (such as Figure 10cAs shown in the figure, when the positioning member is flipped, it can be seen from the side view that the "rounded corner" exists in the lateral direction. It can be seen from this that in the present invention, by providing a holding section 213 and an elastic deformation section 214 on the positioning arm 21, the direction in which the "rounded corner" is generated is changed, so that when the positioning arm 21 is transformed between the restricted state and the released state, its path can greatly reduce the situation that the positioning member 2 turns outwards and scrapes the aortic inner wall tissue during the release process.

[0055] In some embodiments, the control member 22 includes a push-pull rod 221 and a locking structure 222. One end of the push-pull rod 221 is cooperatively connected with the positioning arm 21, and the locking structure 222 is arranged at the other end of the push-pull rod 221.

[0056] In this embodiment, the locking structure 222 is a plurality of protrusions 223 uniformly and symmetrically arranged on the left and right sides of the push-pull rod 221. The protrusions 223 are made of a shape memory material (such as nickel-titanium alloy). When the positioning member 2 is released in the heart, the positioning member 2 drives its locking structure 222 to return to a preset shape, so that the protrusions 223 pass through the fixing holes 11 and are fixed. At this time, the connection between the locking structure 222 and the fixing holes 11 is similar to the form of a "snap fastener".

[0057] In this embodiment, the stent body 1 is provided with fixing holes 11 corresponding to the locking structure 222. When the positioning member 2 is in the released state, the locking structure 222 is cooperatively connected with the fixing holes 11. The fixing holes 11 are arranged at the distal end of the stent body 1, and the control member 22 is inserted through the fixing holes 11. When the valve prosthesis is loaded into the sheath, the positioning member 2 is in the restricted state, and the control member 22 axially pulls the positioning arm 21, so that the positioning arm 21 deforms, so that the positioning arm 21 and the control member 22 do not overlap, and it can greatly reduce the diameter of the sheath tube during valve loading (as Figures 3a - 3c shown); different from the prior art, the positioning member 2 is arranged on the outer periphery of the stent body 1. During valve loading, the positioning member 2 overlaps with the stent body 1, which will inevitably increase the diameter of its loading sheath tube, resulting in that its replacement surgery cannot be implanted percutaneously and must be implanted through the apex of the heart, which causes greater trauma to the patient and is not conducive to the patient's postoperative recovery.

[0058] In some more preferred embodiments, two or more locking structures 222 are arranged on the push-pull rod 221, and at the same time, the stent body 1 is also provided with fixing holes 11 corresponding to the locking structures 222. The advantage of such a design is that it can enhance the stability of the connection between the push-pull rod 221 and the stent body 1, and can more effectively avoid the situation that the positioning arm 21 turns outwards and scrapes the aortic inner wall during the process of restoring the preset shape, and effectively improve the success rate of the release and recovery of the positioning member 2.

[0059] In this embodiment, the control member 22 is made of a shape memory material; the control member 22 can be made of a metal memory material (such as nitinol), and the control member 22 is set to be rigid; the purpose of such a design is that when the positioning member 2 is in the released state, the cooperation connection between the control member 22 and the stent body 1 can increase the supporting force of the positioning member 2 and ensure the stability of the stent body 1 in the heart position.

[0060] In this embodiment, the control member 22 is arranged in a "person" - shaped structure; one end of the control member 22 with bifurcations is connected to the positioning arm 21, and the two connection points of the control member 22 on the positioning arm 21 are symmetrically arranged about the push - pull rod 221 as the axis, which can ensure the stability of its connection structure and prevent path deviation; and during the pulling process of the control member 22, the pulling force received by the positioning arm 21 is more uniform, and the deformation during the stretching process is more stable.

[0061] In this embodiment, the positioning arm 21 is made of a shape memory material, and the preset shape of the positioning arm 21 is a "U" - shaped or "V" - shaped or "W" - shaped; in a preferred embodiment, the positioning arm 21 is set to a "U" - shaped structure, and after the positioning arm 21 is released, the arc section of the "U" - shape is positioned in the sinus.

[0062] In some preferred embodiments, as Figure 4g shown, barbs are provided on the surface of the positioning arm 21, or the surface of the positioning arm 21 is coated with a film. The barbs are made of a metal memory material. After the positioning arm 21 resumes its preset shape, the barbs can increase the friction force on the heart tissue and effectively avoid the situation of the stent body 1 falling off in the heart.

[0063] In some embodiments, the surface of the stent body 1 is coated with a film, and the film material includes a metal material, polytetrafluoroethylene, polyethylene, polypropylene, polyester or an animal - derived material.

[0064] The working process and working principle of this embodiment are as follows:

[0065] First, the heart valve prosthesis deforms the positioning arm 21 by pulling the control member 22. The positioning arm 21 is pulled to a set position (the set position is when the free end 212 of the positioning arm 21 does not overlap with the stent body 1). Subsequently, the heart valve prosthesis is compressed within the delivery sheath 4. One end of the control member 22 is cooperatively connected to the delivery sheath 4, causing the positioning arm 21 to remain in the set position. At this time, the heart valve prosthesis is in a restricted state;; when the delivery sheath 4 delivers and needs to release the heart valve prosthesis, the control member 22 is released and one end of the control member 22 is pushed so that the free end 212 of the positioning arm 21 overlaps with the stent body 1 until the positioning arm 21 returns to its preset shape. The locking structure 222 on one end of the control member 22 is cooperatively connected within the fixing hole 11, fixing the positioning arm 21 and also providing a certain supporting force for the positioning arm 21. At this time, the free end 212 of the positioning arm 21 is positioned at the target position we need. Subsequently, the stent body 1 and the artificial valve 3 are released, completing the implantation of the heart valve prosthesis (as Figures 4a - 4f shown). Specific Embodiment Two:

[0067] To better clarify the working principle of the present invention, the release process of the artificial valve 3 prosthesis of the present invention will be gradually described below:

[0068] As Figure 7 shown, when the heart valve prosthesis is used to treat aortic valve diseases, as shown in the figure, it includes a stent body 1, a positioning member 2, and an artificial valve 3. The artificial valve 3 is connected to the stent body 1. The positioning member 2 includes a positioning arm 21 and a control member 22. One end of the control member 22 is cooperatively connected to the positioning arm 21. The positioning arm 21 has a fixed end 211 and a free end 212. The fixed end 211 is fixedly connected to the stent body 1. When the control member 22 pulls the positioning arm 21, the free end 212 of the positioning arm 21 moves along the height direction of the stent body 1. When the positioning member 2 is in the release state, the positioning arm 21 returns to its preset shape; when the positioning member 2 is in the restricted state, the free end 212 of the positioning arm 21 does not overlap with the stent body 1, which can greatly reduce the diameter of the valve sheath for loading it, enabling a transvascular replacement surgery for the patient, greatly reducing the trauma to the patient, and being beneficial to the patient's postoperative recovery (as Figures 8a - 8c shown).

[0069] In this embodiment, the number of the positioning members 2 is 3. After release, the positioning members 2 are at the bottom of the natural aortic sinus of the patient. The positioning members 2 provide a certain supporting force for the stent body 1 within the heart, ensuring that the stent body 1 can be safely and accurately released / implanted into the target position while preventing the stent body 1 from being "washed away" by the blood in the heart.

[0070] In some embodiments, the positioning arm 21 includes a holding section 213 and an elastic deformation section 214. The holding section 213 is located at the free end 212 of the positioning arm 21, and the elastic deformation section 214 is located between the holding section 213 and the fixed end 211 of the positioning arm 21.

[0071] In some embodiments, the elastic deformation section 214 is flexible relative to the holding section 213. When the positioning member 2 is switched from the restricted state to the released state, the elastic deformation section 214 deforms until it returns to a preset shape.

[0072] In another embodiment, the control member 22 is a wire or filament, and the control member 22 is detachably connected to the positioning arm 21. When the positioning member 2 is in the released state, the control member 22 is separated from the positioning arm 21, so that the positioning arm 21 returns to a preset shape.

[0073] In some preferred embodiments, the control member 22 can be a single-strand wire or filament, or can be a multi-strand wire or filament. One end of the control member 22 connected to the positioning arm 21 is detachably connected. The purpose of such a design is to greatly reduce the implant, reduce the contact and irritation to the intracardiac tissue, and is beneficial to the postoperative recovery of the patient.

[0074] In some embodiments, the positioning arm 21 is made of a shape memory material, and the preset shape of the positioning arm 21 is a "U" shape, a "V" shape, or a "W" shape.

[0075] In some embodiments, barbs are provided on the surface of the positioning arm 21, or the surface of the positioning arm 21 is coated with a film. The barbs are made of a metal memory material. After the positioning arm 21 returns to the preset shape, the barbs can increase the friction force on the intracardiac tissue, and can effectively avoid the situation that the stent body 1 falls off in the heart.

[0076] In some embodiments, the surface of the stent body 1 is coated with a film, and the film material includes a metal material, polytetrafluoroethylene, polyethylene, polypropylene, polyester, or an animal-derived material.

[0077] The working process and working principle of this embodiment are as follows:

[0078] First, the heart valve prosthesis deforms the positioning arm 21 by pulling the control member 22. The positioning arm 21 is pulled to a set position (the set position is when the free end 212 of the positioning arm 21 does not overlap with the stent body 1). Subsequently, the heart valve prosthesis is compressed within the delivery sheath 4. One end of the control member 22 is cooperatively connected to the delivery sheath 4 such that the positioning arm 21 remains in the set position. At this time, the heart valve prosthesis is in a restricted state. When the delivery sheath 4 delivers and needs to release the heart valve prosthesis, the release control member 22 is actuated to separate the end of the control member 22 connected to the positioning arm 21. Since the positioning arm 21 is made of a shape memory material, the positioning arm 21 will utilize the characteristics of its own material to return to the preset shape as it separates from the control member 22. At this time, the free end 212 of the positioning arm 21 is positioned at the target position we need. Subsequently, the stent body 1 and the artificial valve 3 are released to complete the implantation of the heart valve prosthesis (as Figures 9a - 9d shown).

[0079] The technology of the present invention is applicable not only to the aortic valve but also to patients with mitral or tricuspid valve lesions.

[0080] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A valve prosthesis with variable positioning members, characterized in that, It includes a stent body, a positioning member and an artificial valve. The artificial valve is connected to the stent body. The positioning member includes a positioning arm and a control member. The positioning arm is made of a shape memory material. The preset shape of the positioning arm is a "U" shape, a "V" shape or a "W" shape. The control member is arranged in a "human" shape structure. The control member includes a push-pull rod and a locking structure. One end of the push-pull rod corresponding to the bifurcation of the "human" shape structure is connected to the positioning arm to form two connection points. The locking structure is arranged at the other end of the push-pull rod. The two connection points are symmetrically arranged left and right with the push-pull rod as the axis. The positioning arm has a fixed end and a free end. The fixed end is fixedly connected to the stent body. The stent body is provided with a fixing hole corresponding to the locking structure. The positioning arm includes a holding section and an elastic deformation section. The holding section is located at the free end of the positioning arm and between the two connection points. The elastic deformation section is located between the holding section and the fixed end of the positioning arm. When the control member axially pulls the positioning arm, the free end of the positioning arm moves along the height direction of the stent body, and the positioning arm is in a restricted state. When the control member axially pushes the positioning arm, the positioning arm is converted from the restricted state to the released state, and the elastic deformation section deforms until it returns to the preset shape, and the locking structure is connected to the fixing hole in cooperation. Since the elastic deformation section is flexible relative to the holding section, during the recovery process, the elastic deformation section is converted from a straightened state to a bent state close to a "U" shape until it returns to the preset straightened form, and during this process, the pushing and pulling direction of the control member always remains axial, while reducing the situation of the positioning arm turning outwards during the recovery process.

2. The valve prosthesis with variable positioning member according to claim 1, characterized in that, The locking structure is a plurality of protrusions evenly and symmetrically arranged on the left and right sides of the push-pull rod.

3. A valve prosthesis with a variable positioning member according to claim 1, characterized in that, The control member is made of a shape memory material.

4. A valve prosthesis system with variable positioning members, characterized in that, It includes a control handle, an outer sheath, a controllable release device and a valve prosthesis with a variable positioning member as described in any one of claims 1 to 3. The stent body is connected to the controllable release device in cooperation. One end of the control member is detachably connected to the positioning arm, and the other end of the control member is connected to the control handle in cooperation. When the control handle is operated to axially pull the control member, the free end of the positioning arm moves along the height direction of the stent body, and the positioning arm is gradually retracted into the gap between the stent body and the outer sheath until the elastic deformation section does not overlap with the part of the stent where the artificial valve is located. At this time, the positioning arm is in a restricted state. When the control handle is operated in the reverse direction, the positioning arm gradually extends out of the gap between the stent body and the outer sheath and returns to the preset shape. At this time, the positioning arm is in the released state.

5. A valve prosthesis system with a variable positioning member according to claim 4, characterized in that, Before the stent body is completely separated from the controllable release device, the positioning arm can be converted between the restricted state and the released state multiple times.

6. A valve prosthesis system with a variable positioning member according to claim 4, wherein The controllable release device includes a distal release device and a proximal release device. The distal release device is located at the distal part of the valve prosthesis system. Before the distal part of the stent body is completely disengaged from the distal release device, the distal part of the stent body is arranged in a collapsed state within the distal release device.

7. A valve prosthesis system with a variable positioning member according to claim 6, characterized in that, The proximal release device is arranged within the outer sheath and is detachably connected in cooperation with the proximal end of the stent body. Before the positioning member and the distal part of the stent body are completely released, the proximal part of the stent body is restricted from being released by the proximal release device.

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