Degradable medical metal heart occluder and processing technology

Abstract

The invention discloses a degradable medical metal heart plugging device and a processing technology. The degradable medical metal heart plugging device comprises a first plugging part, a second plugging part and a fixing assembly, the first plugging part and the second plugging part are located at the two ends of the fixing assembly respectively and located on the two sides of the heart oval foramen respectively. The first end of the first plugging part and the first end of the second plugging part are both fixedly connected with the fixing assembly, the second end of the first plugging part and the second end of the second plugging part are both slidably connected with the first end of the fixing assembly, and the length between the first end of the second plugging part and the first end of the first plugging part is equal to a first distance; the diameter of the first plugging part is larger than that of the second plugging part. The problem of long-term in-vivo retention of the non-degradable plugging device can be effectively avoided, and the plugging effect and the implanting effect are greatly improved; the plugging success rate is improved on the operation level, meanwhile, mechanical support for plugging can be better provided for an implantation part, and the plugging success rate is improved on the treatment level.

Description

Technical Field

[0001] The present invention relates to the field of occluders, and more particularly, to a degradable medical metal cardiac occluder and a processing technology. Background Art

[0002] Patent Foramen Ovale (PFO) is considered to be one of the causes of stroke. Among the young population, the probability of patients with unexplained stroke complicated with PFO is 2.9 times that of the general population. In 2022, the Society for Cardiovascular Angiography and Interventions in the United States defined PFO-associated stroke as PFO complicated with unexplained stroke in the guidelines for the management of patent foramen ovale.

[0003] The foramen ovale is a thin sheet-like channel located in the fossa ovalis of the interatrial septum that communicates between the left and right atria. The foramen ovale is open during fetal development, allowing venous blood to bypass the non-functional lungs and flow directly into the left heart. Due to the establishment of normal breathing and the increase in left heart pressure, this channel generally closes spontaneously after birth. In the general population, 27% of people still have an open foramen ovale after one year of age, which is called PFO. PFO mainly causes stroke through paradoxical embolism. In addition to stroke, PFO can also cause other diseases, including migraine, peripheral vascular embolism, etc., and is a hidden health "killer".

[0004] PFO interventional occlusion therapy uses an interventional occluder to block the patent foramen ovale, which is the main current treatment for patent foramen ovale. Since 2020, PFO occlusion therapy has been carried out in China, and the number of cases has exceeded 40,000 by 2022. Currently, all clinical PFO interventional occlusion therapies use a disc-shaped metal occluder with nitinol alloy as the main material. This occluder mainly uses high-strength shape memory nitinol alloy wires and is made into a self-expanding cardiac occluder through braiding and preforming processes. As the most commonly used metal material for occlusion therapy, nitinol alloy has the characteristics of good support force, strong compliance, and being able to be visualized under radiation. Once implanted, it will accompany the patient for the rest of their life, increasing the probability of thrombus formation, and the metal implant will prevent the patient from undergoing magnetic resonance imaging for the rest of their life. It occupies the true atrial septum, excluding some possible minimally invasive treatment options in the future. Currently, the average age of patients undergoing PFO interventional occlusion is only 41 years old, and the number of interventional surgeries for congenital heart diseases in China is increasing steadily. By 2022, the number of interventional cases of atrial septal defect completed in China was approximately 46,100, patent ductus arteriosus was about 12,500, and ventricular septal defect was about 12,500. The age of patients undergoing interventional treatment for congenital heart diseases is even younger. The non-degradable occluder will accompany them for life and may also cause more serious impacts. Therefore, the development of a degradable cardiac occluder is very important. Currently, there are several partially degradable occluders under research, and most of them have not been successfully applied clinically. These occluders all use polymer materials, including polydioxanone (PPDO), polylactic acid (PLA), poly(lactic-co-glycolic acid) (PLGA), polycaprolactone (PCL), etc. However, the degradation mode of polymers is the way of molecular chain breakage. The disintegration of this polymer chain is very likely to occur before the endothelialization of the occluder, thus triggering the problem of vascular system infarction and posing a great safety hazard. More critically, the mechanical strength of polymer materials is poor, and the memory resilience is also poor, making it difficult to achieve a stable cardiac occlusion effect. At the same time, polymer materials do not have X-ray imaging properties and can only achieve the implantation of the occluder through the auxiliary means of B-ultrasound, which requires extremely high technical and experience requirements for surgeons and is very likely to cause the problem of occlusion failure.

[0005] Therefore, how to provide a degradable medical metal cardiac occluder and its processing technology has become an urgent technical problem to be solved in this field. Summary of the Invention

[0006] An object of the present invention is to provide a new technical solution for a degradable medical metal cardiac occluder and its processing technology.

[0007] According to the first aspect of the present invention, a degradable medical metal cardiac occluder is provided, including: a first occlusion part, a second occlusion part, and a fixing component;

[0008] The first blocking portion and the second blocking portion are respectively located at two ends of the fixing component, on both sides of the cardiac foramen ovale, and there is a first distance between the first blocking portion and the second blocking portion;

[0009] The first end of the first blocking portion is fixedly connected to the fixing component, and the second end of the first blocking portion is slidably connected to the first end of the fixing component; the first end of the second blocking portion is fixedly connected to the fixing component, and the second end of the second blocking portion is slidably connected to the second end of the fixing component; and the length between the first end of the second blocking portion and the first end of the first blocking portion is equal to the first distance;

[0010] The diameter of the first blocking portion is greater than the diameter of the second blocking portion.

[0011] Optionally, the first blocking portion includes a plurality of first blocking sheets, a first connecting ring and a first fixing ring. The plurality of first blocking sheets are arranged at intervals along the circumference of the first end of the fixing component, and the first connecting ring and the first fixing ring are respectively arranged at both ends of the first blocking sheet;

[0012] Both the first fixing ring and the first connecting ring are sleeved on the fixing component, and the first fixing ring is fixedly connected to the fixing component, and the first connecting ring is slidably connected to the fixing component.

[0013] Optionally, the second blocking portion includes a plurality of second blocking sheets, a second connecting ring and a second fixing ring. The plurality of second blocking sheets are arranged at intervals along the circumference of the second end of the fixing component, and the second connecting ring and the second fixing ring are respectively arranged at both ends of the first blocking sheet;

[0014] Both the second fixing ring and the second connecting ring are sleeved on the fixing component, and the second fixing ring is fixedly connected to the fixing component, and the second connecting ring is slidably connected to the fixing component; the length of the first blocking sheet is greater than the length of the second blocking sheet.

[0015] Optionally, the orthographic projection of the connection between the first end of the same first blocking sheet and the first connecting ring does not coincide with the connection between the second end of the same first blocking sheet and the first fixing ring;

[0016] The orthographic projection of the connection between the first end of the same second blocking sheet and the second connecting ring does not coincide with the connection between the second end of the same second blocking sheet and the second fixing ring.

[0017] Optionally, the fixing component includes a connecting rod and fixing nuts. The first plugging portion and the second plugging portion are respectively located at two ends of the connecting rod, and the fixing nuts are threadedly connected to two ends of the connecting rod respectively for fixing the first plugging portion and the second plugging portion.

[0018] Optionally, the materials of the first plugging portion, the second plugging portion and the fixing component are all degradable medical metals.

[0019] According to the first aspect of the present invention, a processing technology for a degradable medical metal cardiac occluder is provided, including the following steps:

[0020] Adopt a wavy curve structure annular array distribution to design the size information of the first plugging piece and the second plugging piece;

[0021] Obtain a metal ingot;

[0022] Conduct continuous rolling on the metal ingot to obtain a metal sheet with a thickness of 2 mm;

[0023] Laser cut the metal sheet according to the size information of the first plugging piece and the second plugging piece to obtain 12 first plugging pieces and second plugging pieces with different sizes;

[0024] Install 12 first plugging pieces and second plugging pieces with different sizes into the connecting rod and fix them with fastening bolts to form a cardiac occluder.

[0025] Optionally, after obtaining the metal ingot, perform multiple annealing process treatments on the metal ingot. The multiple annealing process includes a first annealing and a second annealing. The first annealing is to heat up to 250 °C at a rate of 5 °C / min and hold for 2 h, and the second annealing is to heat up to 350 °C at a rate of 1 °C / min and hold for 2 h.

[0026] Optionally, the rolling parameters are: the reduction per pass is 90%, the roll speed is 0.3 m / s. After rolling, perform heat treatment and polish the metal ingot with sandpaper.

[0027] Optionally, the number of annular array units of the wavy curve structure annular array is 6 - 20 array units.

[0028] The beneficial effects of the present invention are as follows:

[0029] The cardiac occluder made of a medical degradable metal material according to the present invention can be gradually degraded after the endothelialization of the defect position after being implanted into the body, which can effectively avoid a series of problems caused by the long-term retention of non-degradable occluders in the body; moreover, the degradation mode of the degradable medical metal material is ion dissolution degradation, which avoids the potential safety hazards caused by the device cracking caused by the swelling and molecular bond breaking of polymers.

[0030] Moreover, by setting the diameter of the first occlusion part to be larger than that of the second occlusion part, with the first occlusion part and the second occlusion part located at both ends of the fixing component respectively, on both sides of the cardiac foramen ovale, and having a first distance between the first occlusion part and the second occlusion part, the occlusion effect and the implantation effect are greatly improved; not only is the occlusion success rate improved at the surgical level, but also better mechanical support for the implantation site can be provided, and the occlusion success rate is improved at the treatment level.

[0031] Other features and advantages of the present invention will become clear from the following detailed description of the exemplary embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings incorporated in and constituting a part of this specification illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0033] Figure 1 It is a structural diagram of the degradable medical metal cardiac occluder of the present invention;

[0034] Figure 2 It is a structural diagram of the degradable medical metal cardiac occluder from another angle of the present invention;

[0035] Figure 3 It is a structural diagram of the degradable medical metal cardiac occluder in an initial state of the present invention;

[0036] Figure 4 It is a flowchart of the processing technology of the degradable medical metal cardiac occluder of the present invention.

[0037] The labels in the figures are as follows: 1. First occlusion part; 11. First occlusion piece; 12. First upper bending segment; 13. First lower bending segment; 2. Second occlusion part; 21. Second occlusion piece; 22. Second upper bending segment; 23. Second lower bending segment; 3. Fixing component; 31. Connecting rod; 32. Fixing nut. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] Now, various exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that: unless otherwise specifically stated, the relative arrangements, numerical expressions, and numerical values of the components and steps set forth in these embodiments do not limit the scope of the present invention.

[0039] The following description of at least one exemplary embodiment is merely illustrative in nature and in no way serves as a limitation on the present invention or its application or use.

[0040] Techniques, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered as part of the specification.

[0041] In all examples shown and discussed herein, any specific values should be construed as merely exemplary and not as a limitation. Thus, other examples of the exemplary embodiments may have different values.

[0042] As Figures 1 to 3 shown, an embodiment of the present invention provides a degradable medical metal cardiac occluder, comprising: a first occluding portion 1, a second occluding portion 2, and a fixing assembly 3.

[0043] The first occluding portion 1 and the second occluding portion 2 are respectively located at both ends of the fixing assembly 3, on both sides of the cardiac foramen ovale, and there is a first distance between the first occluding portion 1 and the second occluding portion 2.

[0044] The first end of the first occluding portion 1 is fixedly connected to the fixing assembly 3, and the second end of the first occluding portion 1 is slidably connected to the first end of the fixing assembly 3; the first end of the second occluding portion 2 is fixedly connected to the fixing assembly 3, and the second end of the second occluding portion 2 is slidably connected to the second end of the fixing assembly 3; and the length between the first end of the second occluding portion 2 and the first end of the first occluding portion 1 is equal to the first distance.

[0045] The diameter of the first occluding portion 1 is greater than the diameter of the second occluding portion 2.

[0046] In the initial state, both the first occluding portion 1 and the second occluding portion 2 are elliptical structures, and the diameter of the first end of the first occluding portion 1 is smaller than the diameter of the second end of the first occluding portion 1, and the diameter of the first end of the second occluding portion 2 is smaller than the diameter of the second end of the second occluding portion 2, and its structure is similar to the shape of an egg.

[0047] As Figure 3 shown, when installed in the cardiac foramen ovale of a patient, the first occluding portion 1 and the second occluding portion 2 are respectively located on both sides of the cardiac foramen ovale. First, the first occluding portion 1 and the second occluding portion 2 in the initial state are placed in the cardiac foramen ovale; then, through the action of the fixing assembly 3, the second end of the second occluding portion 2 moves towards the first end of the second occluding portion 2, so that the second occluding portion 2 is compressed to form a circular structure; then, the second end of the first occluding portion 1 moves towards the first end of the first occluding portion 1, so that the first occluding portion 1 is compressed to form a circular structure, so that both the first occluding portion 1 and the second occluding portion 2 expand and open to form a double-umbrella structure to achieve the occluding effect of the cardiac foramen ovale.

[0048] The present invention adopts a cardiac occluder made of a medical degradable metal material, which gradually degrades after the endothelialization of the defect position in the body, and can effectively avoid a series of problems caused by the long-term retention of non-degradable occluders in the body; moreover, the degradation mode of the degradable medical metal material is ion dissolution degradation, avoiding the safety hazards brought by the device cracking caused by the swelling of polymers and the breaking of molecular bonds.

[0049] Furthermore, in the present invention, by setting the diameter of the first occluding portion 1 to be larger than the diameter of the second occluding portion 2, the first occluding portion 1 and the second occluding portion 2 are respectively located at both ends of the fixing assembly 3, on both sides of the cardiac foramen ovale respectively, and there is a first distance between the first occluding portion 1 and the second occluding portion 2, which greatly improves the occluding effect and the implantation effect; not only improves the occluding success rate at the surgical level, but also can better provide mechanical support for the implanted part, and improves the occluding success rate at the treatment level.

[0050] In an embodiment of the degradable medical metal cardiac occluder of the present invention, as Figure 2 shown, the first occluding portion 1 includes a plurality of first occluding sheets 11, a first connecting ring and a first fixing ring. The plurality of first occluding sheets 11 are arranged at intervals along the circumference of the first end of the fixing assembly 3, and the first connecting ring and the first fixing ring are respectively arranged at both ends of the first occluding sheet 11.

[0051] Both the first fixing ring and the first connecting ring are sleeved on the fixing assembly 3, and the first fixing ring is fixedly connected to the fixing assembly 3, and the first connecting ring is slidably connected to the fixing assembly 3.

[0052] Specifically, there are 12 first occluding sheets 11. In the initial state, the side walls of the 12 first occluding sheets 11 are in contact with each other or have a certain distance. Under the action of the fixing assembly 3, the second end of the first occluding sheet 11 faces the first end of the first occluding sheet 11, and the 12 first occluding sheets 11 expand due to being affected and form a circular structure. There is a distance between two adjacent first occluding sheets 11. When the first occluding sheet 11 is squeezed, the center line of the first occluding sheet 11 is a curved structure.

[0053] The first occluding sheet 11 includes a first upper bending segment 12 and a first lower bending segment 13. The first end of the first upper bending segment 12 is a fixed end and is connected to the first fixing ring. The first end of the first lower bending segment 13 is a mobile end and is connected to the first connecting ring. The second end of the first upper bending segment 12 is connected to the second end of the first lower bending segment 13. When the mobile end of the first lower bending segment 13 moves towards the fixed end of the first upper bending segment 12, the first lower bending segment 13 is an S-shaped structure, and the first upper bending segment 12 is an arc-shaped structure.

[0054] Among them, the orthographic projection of the first upper bending segment 12 coincides with the first lower bending segment 13 only at one place, and the coincidence is close to the moving end of the first lower bending segment 13 and the fixed end of the first upper bending segment 12.

[0055] In an embodiment of the degradable medical metal cardiac occluder of the present invention, the second occluding portion 2 includes a plurality of second occluding sheets 21, a second connecting ring and a second fixing ring. The plurality of second occluding sheets 21 are arranged at intervals along the circumference of the second end of the fixing component 3. The second connecting ring and the second fixing ring are respectively arranged at both ends of the first occluding sheet 11.

[0056] Both the second fixing ring and the second connecting ring are sleeved on the fixing component 3, and the second fixing ring is fixedly connected to the fixing component 3, and the second connecting ring is slidably connected to the fixing component 3; the length of the first occluding sheet 11 is greater than the length of the second occluding sheet 21.

[0057] Specifically, there are 12 second occluding sheets 21. In the initial state, the side walls of the 12 second occluding sheets 21 are in contact with each other or have a certain distance. Under the action of the fixing component 3, the second ends of the second occluding sheets 21 face the first ends of the second occluding sheets 21, and the 12 second occluding sheets 21 are expanded to form a circular structure. There is a distance between two adjacent second occluding sheets 21. When the second occluding sheet 21 is squeezed, the center line of the second occluding sheet 21 is a curved structure.

[0058] The second occluding sheet 21 includes a second upper bending segment 22 and a second lower bending segment 23. The first end of the second upper bending segment 22 is a fixed end and is connected to the second fixing ring. The first end of the second lower bending segment 23 is a moving end and is connected to the second connecting ring. The second end of the second upper bending segment 22 is connected to the second end of the second lower bending segment 23. When the moving end of the second lower bending segment 23 moves towards the fixed end of the second upper bending segment 22, the second lower bending segment 23 is an S-shaped structure, and the second upper bending segment 22 is an arc-shaped structure.

[0059] Among them, the orthographic projection of the second upper bending segment 22 coincides with the second lower bending segment 23 only at one place, and the coincidence is close to the moving end of the second lower bending segment 23 and the fixed end of the second upper bending segment 22.

[0060] In addition, since the length of the first occluding sheet 11 is greater than the length of the second occluding sheet 21, when the first occluding sheet 11 and the second occluding sheet 21 are compressed, the diameter of the circular structure formed by compressing the first occluding sheet 11 is greater than the diameter of the circular structure formed by compressing the second occluding sheet 21.

[0061] It should be noted that chamfers are used at the joints of the first sealing piece 11 with the first connecting ring and the first fixing ring, and at the joints of the second sealing piece 21 with the second connecting ring and the second fixing ring to avoid stress concentration caused by acute-angle connection and the resulting fracture problem.

[0062] In an embodiment of the degradable medical metal heart occluder of the present invention, the orthographic projection of the joint of the first end of the same first sealing piece 11 with the first connecting ring does not coincide with the joint of the second end of the same first sealing piece 11 with the first fixing ring.

[0063] The orthographic projection of the joint of the first end of the same second sealing piece 21 with the second connecting ring does not coincide with the joint of the second end of the same second sealing piece 21 with the second fixing ring. With this arrangement, when the first sealing piece 11 and the second sealing piece 21 are compressed, they can expand within a larger range.

[0064] In an embodiment of the degradable medical metal heart occluder of the present invention, the fixing assembly 3 includes a connecting rod 31 and fixing nuts 32. The first occluding portion 1 and the second occluding portion 2 are respectively located at both ends of the connecting rod 31, and the fixing nuts 32 are threadedly connected to both ends of the connecting rod 31 respectively. The fixing nuts 32 are used to fix the first occluding portion 1 and the second occluding portion 2.

[0065] Specifically, both ends of the connecting rod 31 have threaded portions, and there is a second distance between the two threaded portions. The outer diameter of the fixing nut 32 is 2 mm, the inner diameter is 1 mm, and the thickness is 1 mm. The length of the connecting rod 31 is 8 mm and the diameter is 1 mm.

[0066] Both fixing nuts 32 abut against the second ends of the first sealing piece 11 and the second sealing piece 21. Under the action of the two fixing nuts 32, the second ends of the first sealing piece 11 and the second sealing piece 21 respectively face the first end of the first sealing piece 11 and the first end of the second sealing piece 21, thereby compressing the first sealing piece 11 and the second sealing piece 21 to form a circular structure, thus providing a fixing effect on the degradable medical metal heart occluder of the present invention.

[0067] The first sealing piece 11 and the second sealing piece 21 are successively and fixedly stacked onto the connecting rod 31 in a fixed clockwise or counterclockwise manner.

[0068] In addition, the edges of the first occluding portion 1, the second occluding portion 2, and the fixing assembly 3 are polished.

[0069] In an embodiment of the degradable medical metal heart occluder of the present invention, the materials of the first occluding portion 1, the second occluding portion 2, and the fixing assembly 3 are all degradable medical metals.

[0070] Specifically, the first blocking portion 1, the second blocking portion 2, and the fixing component 3 can be made of at least one biodegradable medical metal material such as zinc alloy, magnesium alloy, and ferroalloy.

[0071] According to the first aspect of the present invention, a processing technology for a biodegradable medical metal heart occluder is provided. As Figure 4 shown, it includes the following steps:

[0072] Adopt a wavy curve structure for circular array distribution to design the size information of the first occluding piece and the second occluding piece; the number of circular arrays of the wavy curve structure circular array is 6 - 20 array units. Through the design of the curve structure, the installation performance and flexible deformation ability of the first occluding piece and the second occluding piece are increased. At the same time, the buckling degree of the final first occluding piece and the second occluding piece can be adjusted by coordinating the curvature size of the curve structure or the arc radius of the curve.

[0073] For the amplification of the width dimension in the high - stress area after subsequent assembly, it can be achieved by increasing the local width dimension of the first occluding piece and the second occluding piece, thereby reducing the degradation rate in this area, and thus realizing the control of the degradation behavior of the entire device.

[0074] Obtain a metal ingot; specifically, the metal ingot is obtained by vacuum induction melting of biodegradable medical metals (such as magnesium alloy, zinc alloy, and ferroalloy).

[0075] Perform continuous rolling on the metal ingot to obtain a metal sheet with a thickness of 2 mm;

[0076] Laser - cut the metal sheet according to the size information of the first occluding piece and the second occluding piece to obtain 12 first occluding pieces and second occluding pieces with different sizes;

[0077] Install the 12 first occluding pieces and second occluding pieces with different sizes into the connecting rod and fix them with fastening bolts to form a heart occluder.

[0078] The present invention is a process for developing in - vivo devices made of biodegradable medical metal materials. Compared with the traditional forming process of first wire - drawing and then weaving for heart occluders, it has the advantage of controllable degradation structure of the device. Because whether it is wire - drawing forming of metal materials or wire - drawing forming of polymer materials, only wires with uniform diameters can be obtained, and the purpose of adjusting the dimensions at different positions cannot be achieved. In the present invention, by setting the first occluding piece and the second occluding piece as a wavy flexible curve structure and adjusting the dimensions in the width direction of the first occluding piece and the second occluding piece, controllable degradation of the overall device and adjustment of the degradation rate can be realized.

[0079] In an embodiment of the processing technology of the degradable medical metal cardiac occluder of the present invention, after obtaining the metal ingot, the metal ingot is subjected to multiple annealing processes. The multiple annealing processes include the first annealing and the second annealing. The first annealing is to raise the temperature to 250 °C at a rate of 5 °C / min and hold for 2 h. The second annealing is to raise the temperature to 350 °C at a rate of 1 °C / min and hold for 2 h.

[0080] Specifically, after obtaining the metal ingot, then raise the temperature to 250 °C at a rate of 5 °C / min, hold for 2 h, then raise the temperature to 350 °C at a rate of 1 °C / min, hold for 2 h, and perform homogenization annealing by furnace cooling to obtain an ingot with uniform structure.

[0081] In an embodiment of the processing technology of the degradable medical metal cardiac occluder of the present invention, the rolling parameters are: the amount of reduction per pass is 90%, the roll speed is 0.3 m / s. After rolling, heat treatment is carried out, and the metal ingot is polished with sandpaper.

[0082] Specifically, taking 20 mm as an example, the roll speed is 0.3 m / s and it is held at 350 °C for 1 h; then, rolling is carried out with the rolling parameters of 17 mm, 14 mm, and 11 mm, and tempering is carried out at 350 °C for 15 min; then, rolling is carried out with the parameters of 8 mm and 5 mm, quenching is carried out, and it is held at 200 °C for 0.5 h; finally, rolling is carried out with the parameters of 4 mm, 3 mm, and 2 mm to obtain 2 mm, and cross rolling is appropriately carried out during the rolling process. After the heat treatment in the intermediate process, the oxide layer on the surface is timely removed by polishing with sandpaper to avoid phenomena such as peeling during the rolling process.

[0083] The degradable medical metal cardiac occluder of the present invention, with the assistance of the interventional device, can sequentially achieve structural expansion and deployment at the unclosed foramen ovale of the heart, and achieve structural occlusion in the area of the unclosed foramen ovale to prevent blood reflux. At the same time, considering the phenomenon of uneven degradation caused by the stress corrosion problem of the degradable medical metal in the body, a design idea of size strengthening is adopted in the structural design to solve the problems faced by the medical degradable metal in the application of the cardiac occluder.

[0084] Although some specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present invention. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A degradable medical metal cardiac occluder, characterized in that, Comprising: A first occlusion part, a second occlusion part, and a fixing assembly; The first occlusion part and the second occlusion part are respectively located at two ends of the fixing assembly, on both sides of the foramen ovale of the heart, and there is a first distance between the first occlusion part and the second occlusion part; The first end of the first occlusion part is fixedly connected to the fixing assembly, and the second end of the first occlusion part is slidably connected to the first end of the fixing assembly; the first end of the second occlusion part is fixedly connected to the fixing assembly, and the second end of the second occlusion part is slidably connected to the second end of the fixing assembly; and the length between the first end of the second occlusion part and the first end of the first occlusion part is equal to the first distance; The diameter of the first occlusion part is greater than the diameter of the second occlusion part.

2. The biodegradable medical metal cardiac occluder according to claim 1, wherein, The first occlusion part includes a plurality of first occlusion sheets, a first connection ring, and a first fixing ring. The plurality of first occlusion sheets are arranged at intervals along the circumference of the first end of the fixing assembly, and the first connection ring and the first fixing ring are respectively arranged at both ends of the first occlusion sheet; Both the first fixing ring and the first connection ring are sleeved on the fixing assembly, and the first fixing ring is fixedly connected to the fixing assembly, and the first connection ring is slidably connected to the fixing assembly.

3. The degradable medical metal cardiac occluder according to claim 2, wherein, The second occlusion part includes a plurality of second occlusion sheets, a second connection ring, and a second fixing ring. The plurality of second occlusion sheets are arranged at intervals along the circumference of the second end of the fixing assembly, and the second connection ring and the second fixing ring are respectively arranged at both ends of the first occlusion sheet; Both the second fixing ring and the second connection ring are sleeved on the fixing assembly, and the second fixing ring is fixedly connected to the fixing assembly, and the second connection ring is slidably connected to the fixing assembly; the length of the first occlusion sheet is greater than the length of the second occlusion sheet.

4. The degradable medical metal cardiac occluder according to claim 3, wherein The orthographic projection of the connection position between the first end of the same first occlusion sheet and the first connection ring does not coincide with the connection position between the second end of the same first occlusion sheet and the first fixing ring; The orthographic projection of the connection position between the first end of the same second occlusion sheet and the second connection ring does not coincide with the connection position between the second end of the same second occlusion sheet and the second fixing ring.

5. The degradable medical metal cardiac occluder according to claim 1, characterized in that, The fixing assembly includes a connecting rod and fixing nuts. The first occlusion part and the second occlusion part are respectively located at two ends of the connecting rod, and the fixing nuts are respectively threadedly connected to both ends of the connecting rod for fixing the first occlusion part and the second occlusion part.

6. The degradable medical metal cardiac occluder according to claim 1, wherein, The materials of the first occlusion part, the second occlusion part, and the fixing assembly are all biodegradable medical metals.

7. A processing technology for a degradable medical metal cardiac occluder, characterized in that, Including the following steps: Adopting a wavy curve structure for annular array distribution to design the size information of the first occlusion sheet and the second occlusion sheet; Obtaining a metal ingot; Performing continuous rolling on the metal ingot to obtain a metal sheet with a thickness of 2 mm; Laser cutting the metal sheet according to the size information of the first occlusion sheet and the second occlusion sheet to obtain 12 first occlusion sheets and second occlusion sheets with different sizes; Installing the 12 first occlusion sheets and second occlusion sheets with different sizes into the connecting rod and fixing them with fastening bolts to form a heart occluder.

8. The processing technology of the degradable medical metal heart occluder according to claim 7, characterized in that, After obtaining the metal ingot, the metal ingot is subjected to a multi-annealing process. The multi-annealing process includes a first annealing and a second annealing. The first annealing is to heat up to 250 °C at a rate of 5 °C / min and hold for 2 h. The second annealing is to heat up to 350 °C at a rate of 1 °C / min and hold for 2 h.

9. The processing technology of the degradable medical metal cardiac occluder according to claim 7, wherein, The rolling parameters are: the reduction per pass is 90%, the roll speed is 0.3 m / s. After rolling, heat treatment is carried out, and the metal ingot is polished with sandpaper.

10. The processing technology of the degradable medical metal cardiac occluder according to claim 7, characterized in that, The number of annular array units of the wavy curve structure annular array is 6 - 20 array units.

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