Vena cava filter and capturing and recycling device thereof

Abstract

The invention relates to a vena cava filter and a capturing and recycling device thereof, and relates to the field of interventional medical instruments.The vena cava filter comprises a filter screen and a recycling pipe, the recycling pipe is arranged at the end of the filter screen, a recycling pipe cavity is formed in the recycling pipe, a clamping hook groove is formed in the inner wall of the end of the recycling pipe cavity, and an elastic clamping hook is arranged in the clamping hook groove; one end of the elastic clamping hook is fixed in the clamping hook groove, the other end of the elastic clamping hook extends towards the filter screen, the end part of the elastic clamping hook extends into the recycling pipe cavity, and a recycling guide magnet spaced from the clamping hook groove is arranged in the recycling pipe cavity. The vena cava filter catching and recycling device comprises a recycling sleeve and a recycling guide wire, a catching head is arranged at one end of the recycling guide wire, the recycling guide wire penetrates through the recycling sleeve, the catching head comprises a catching guide magnet, the magnetism of the opposite ends of the catching guide magnet and the recycling guide magnet is opposite, and a clamping groove is formed in the side wall of the catching head; and the clamping groove and the clamping hook groove are correspondingly arranged, so that the recovery difficulty of the vena cava filter can be reduced.

Description

Technical Field

[0001] This application relates to the field of interventional medical devices, and in particular to an inferior vena cava filter. In addition, this application also relates to a capturing and retrieving device for an inferior vena cava filter. Background Art

[0002] Pulmonary embolism is an acute disease mainly caused by thrombus blocking the pulmonary artery or its branches, with the main symptoms of dyspnea, chest pain, and hemoptysis. It is characterized by a rapid onset process and a high mortality rate. The implantation of an inferior vena cava filter can effectively block large venous thrombi from entering the pulmonary circulation, prevent the occurrence of pulmonary embolism, and has a low incidence of complications. It has been increasingly widely used in the prevention of pulmonary embolism, especially before surgical treatment of deep vein thrombosis.

[0003] An inferior vena cava filter is usually placed into the inferior vena cava by a percutaneous puncture method before venous thrombus treatment to prevent large thrombi from passing through the right heart and entering the pulmonary circulation, reducing the occurrence of pulmonary embolism and preventing fatal pulmonary embolism. After the treatment to remove the venous thrombus, a considerable part of the inferior vena cava filters need to be retrieved to prevent long-term irritation of the filter from causing damage to the inferior vena cava.

[0004] Existing inferior vena cava filters are usually provided with retrieval hooks. During retrieval, a capturing device is inserted into the inferior vena cava through a catheter, and the capturing device is used to grab the retrieval hook with the aid of the imaging of the imaging material and then the filter is taken out. However, intravascular imaging can only obtain two-dimensional planar images, which is difficult to guide the capturing device to accurately grab the retrieval hook, increasing the difficulty of surgical operation. In particular, after the inferior vena cava filter has been placed in the inferior vena cava for a period of time, it may shift due to the pulsation of the accompanying artery and human activities, causing the retrieval hook to contact the wall of the inferior vena cava, and the vascular endothelial cells proliferate and cover the retrieval hook, further increasing the difficulty of retrieving the inferior vena cava filter. Chinese Patent Application CN107374778A discloses an inferior vena cava filter and a retrieval device provided with a magnet, which uses the magnet to realize the combination between the retrieval device and the inferior vena cava filter. However, the volume and magnetic force of the magnet are both small, and it is difficult to form a traction force for retrieving the inferior vena cava filter. Moreover, the contact between the retrieval hook and the adhesion part of the inferior vena cava wall will also affect the capture of the retrieval hook by its retrieval loop or retrieval claw, and it is impossible to effectively reduce the difficulty of retrieving the inferior vena cava filter. Summary of the Invention

[0005] In order to reduce the difficulty of retrieving the inferior vena cava filter, this application provides an inferior vena cava filter and its capturing and retrieving device.

[0006] The inferior vena cava filter provided by this application adopts the following technical solution: A vena cava filter, comprising a filter screen and a recovery tube. The recovery tube is arranged at the end of the filter screen. Inside the recovery tube, there is a recovery tube cavity opening at the end face of the recovery tube. On the inner wall at the end of the recovery tube cavity, there is a snap hook groove, and an elastic snap hook is arranged in the snap hook groove. One end of the elastic snap hook is fixed in the snap hook groove, and the other end extends towards the filter screen and its end extends into the recovery tube cavity. A recovery guiding magnet is arranged in the recovery tube cavity, and the recovery guiding magnet is arranged on the side of the snap hook groove adjacent to the filter screen, and is arranged at an interval from the snap hook groove.

[0007] By adopting the above technical solution, with the guiding magnet arranged in the recovery tube cavity, it can prevent the growth of vascular endothelium into the recovery tube cavity, and is beneficial for the capture head of the recovery device to enter the recovery tube cavity, improving the convenience of the connection between the capture head and the recovery tube. By using the elastic snap hook arranged in the snap groove, the capture head of the recovery device can smoothly enter the recovery tube cavity, and the capture head is snap-connected in the recovery tube cavity, improving the connection strength between the capture head and the recovery tube, and ensuring the reliable recovery of the vena cava filter by the recovery device.

[0008] In a specific feasible embodiment, both the snap hook groove and the elastic snap hook are provided with a plurality of them. The plurality of snap hook grooves are circumferentially and uniformly arranged on the wall of the recovery tube cavity, and each elastic snap hook is arranged in one of the snap hook grooves.

[0009] By adopting the above technical solution, by using a plurality of snap hook grooves circumferentially and uniformly arranged on the wall of the recovery tube cavity, and the elastic snap hooks arranged in each snap hook groove, a stable snap connection can be formed on the capture head of the recovery device, ensuring a stable coaxial connection and uniform force between the capture head and the recovery tube.

[0010] In a specific feasible embodiment, a plurality of end support grooves are arranged on the outer side wall of the recovery tube. The plurality of end support grooves are circumferentially spaced on the outer side wall of the recovery tube, and one end support is arranged in each end support groove. One end of the end support is fixed in the end support groove, and the other end elastically supports outside the end support groove.

[0011] By adopting the above technical solution, by using a plurality of end support grooves arranged on the outer side wall of the recovery tube, and the end supports arranged in the end support grooves, it can support on the blood vessel wall when the vena cava filter is deflected, preventing the end of the recovery tube from contacting the vena cava, resulting in the proliferation of vascular endothelium towards the end of the recovery tube and blocking the recovery tube cavity, and accommodating the end support in the end support groove when recovering the vena cava filter.

[0012] In a specific feasible implementation, the end support includes an elastic support rod and a support cap. One end of the end support groove is provided with a support cap groove. One end of the elastic support rod is fixed on the bottom wall of the end support groove, and the other end is fixedly connected to the support cap. The support cap is arranged at a position corresponding to the support cap groove. Through the elastic deformation of the elastic support rod, the support cap can be received in the support cap groove.

[0013] By adopting the above technical solution, the support cap provided at one end of the elastic support rod can form a large-area contact with the blood vessel wall, reduce the local deformation amount when the blood vessel wall contacts the end support, ensure the reliable separation of the blood vessel wall from the end of the recovery tube, and prevent the end support from damaging the blood vessel wall.

[0014] In a specific feasible implementation, an end face groove is provided on the end face of the recovery tube.

[0015] By adopting the above technical solution, the end face groove provided on the end face of the recovery tube can block the growth and expansion of blood vessel endothelium towards the opening of the recovery tube cavity when the blood vessel endothelium grows on the end face of the recovery tube, and further prevent the blood vessel endothelium from blocking the opening of the recovery tube cavity.

[0016] In a specific feasible implementation, the filter screen includes a distal connection part, a distal elastic support, a positioning part, a filter screen part, and a proximal connection part. The distal elastic support includes a plurality of support metal wires. The positioning part includes a plurality of positioning rods. One ends of the plurality of support metal wires are connected to each other to form the distal connection part, and the other ends are respectively fixedly connected to one ends of the positioning rods. The filter screen part includes a plurality of filter screen metal wires. One ends of the plurality of filter screen metal wires are connected to each other to form the proximal connection part, and the other ends are cross-connected to the other ends of the positioning rods. In the free state, the plurality of support metal wires extend from the distal connection part in different directions towards the periphery, and the plurality of filter screen metal wires extend from the proximal connection part in different directions towards the periphery, supporting the positioning rods at different circumferential positions around the distal connection part and the proximal connection part. And the plurality of positioning rods all extend axially. Positioning spikes are provided on the positioning rods. The distal connection part or the proximal connection part is fixedly connected to one end of the recovery tube.

[0017] By adopting the above technical solution, the distal end of the positioning rod can be supported by using a plurality of supporting metal wires arranged between the distal connection part and the positioning rod, which is conducive to supporting the plurality of positioning rods in the axial position around the blood vessel wall in a free state, and deforming during recovery to gather the plurality of positioning support rods in a position corresponding to the distal connection part, which is conducive to the vena cava filter entering the recovery sleeve of the recovery device for recovery. By using a plurality of filter metal wires cross-connected between the plurality of positioning rods and the proximal connection part, the proximal end of the positioning rod can be supported, which is conducive to forming a filter to intercept larger thrombi in a free state, supporting the plurality of positioning rods in the axial position around the blood vessel wall, and deforming during recovery to gather the plurality of positioning support rods in a position corresponding to the proximal connection part, which is conducive to the vena cava filter as a whole entering the recovery sleeve of the recovery device for recovery.

[0018] The vena cava filter capture and recovery device provided in this application adopts the following technical solution: A vena cava filter capture and recovery device is used to recover the vena cava filter provided by the present application, including a recovery sleeve and a recovery guide wire, one end of the recovery guide wire is provided with a capture head, the recovery guide wire is arranged in the recovery sleeve, and the capture head can extend out of the recovery sleeve and enter the recovery tube cavity, the end of the capture head is provided with a capture guide magnet, the magnetism of the capture guide magnet and the opposite end of the recovery guide magnet are opposite, the side wall of the capture head is provided with a snap-fit ​​groove, and the snap-fit ​​groove is arranged corresponding to the snap-fit ​​hook groove.

[0019] By adopting the above technical solution, the capture head arranged at one end of the recovery guide wire can be sent into the recovery tube cavity of the vena cava filter by controlling the recovery guide wire, so as to form a coaxial connection with the recovery tube and recover the vena cava filter. By using the capture guide magnet with a magnetic pole opposite to the opposite end of the recovery guide magnet on the capture head and the engaging groove arranged on the side wall of the capture head, the capture head can be guided into the recovery tube cavity by the magnetic force between the recovery guide magnet and the capture guide magnet, and after the capture head enters the recovery tube cavity, the recovery guide wire is rotated so that the elastic engaging hook on the vena cava filter is engaged in the engaging groove, which greatly reduces the difficulty of combining the capture device with the vena cava filter through the recovery guide wire.

[0020] In a specific possible implementation manner, one end of the engaging groove opens at the distal end surface of the capturing head, and the other end terminates at a region adjacent to the proximal end surface, and a latent end is provided at the end.

[0021] By adopting the above technical solution, using the latent end arranged at the proximal end of the locking groove, the end of the elastic locking hook can be locked at the latent end when the guide wire is pulled to recover the vena cava filter, preventing the elastic locking hook from escaping from the locking groove, thereby ensuring the reliability of the connection between the capture head and the recovery tube.

[0022] In a specific feasible embodiment, one circumferential side surface of the engaging groove is arranged as a plane extending towards the axis direction, and the other circumferential side surface is arranged as a smooth curved surface extending from the groove bottom to the outer peripheral surface of the capture head.

[0023] By adopting the above technical solution, by arranging one side wall of the engaging groove on the circumferential side of the capture head as a plane extending towards the axis direction and the other side wall of the engaging groove as a smooth curved surface extending from the groove bottom to the outer peripheral surface of the capture head, the elastic engaging hook can be reliably engaged in the engaging groove when the capture head is rotated to one side, forming a connection between the capture head and the recovery tube; while when the capture head is rotated to the other side, the elastic engaging hook is disengaged from the engaging groove, facilitating the separation between the capture head and the recovery tube.

[0024] In a specific feasible embodiment, a recovery guiding surface is provided at the distal end of the lumen of the recovery sleeve.

[0025] By adopting the above technical solution, by using the recovery guiding surface provided at the proximal end of the lumen of the recovery sleeve, the extrusion force formed on the support wire and the positioning part during the recovery of the inferior vena cava filter can be increased, which is beneficial to improving the convenience of the inferior vena cava filter entering the recovery sleeve.

[0026] In summary, the present application includes at least one of the following beneficial technical effects: 1. By arranging a recovery guiding magnet in the recovery tube lumen and a capture guiding magnet on the capture head, when the capture head approaches the recovery tube, the capture head can be guided into the recovery tube lumen by the magnetic force of the magnet, reducing the operation difficulty of connecting the capture head to the recovery tube, thereby reducing the recovery difficulty of the inferior vena cava filter.

[0027] 2. By arranging an engaging hook groove on the inner wall of the end of the recovery tube lumen, arranging an elastic engaging hook in the engaging hook groove, and arranging an engaging groove at the corresponding position on the side wall of the capture head, when the capture head enters the recovery tube lumen, the engaging hook can be pressed into the engaging hook groove, and by rotating the capture head, the end of the engaging hook provided with the engaging hook is engaged in the engaging groove, forming a reliable connection between the capture head and the recovery tube, so that the inferior vena cava filter can be dragged into the recovery sleeve by pulling the recovery guide wire, facilitating and reliably recovering the inferior vena cava filter.

[0028] 3. By arranging one side of the engaging groove as a plane extending towards the axis direction and the other side as a smooth curved surface extending from the groove bottom to the outer peripheral surface of the capture head, the elastic engaging hook can be disengaged from the engaging groove by rotating the capture head in the reverse direction, facilitating the disconnection between the capture head and the recovery tube; while when pulling the recovery guide wire, the end of the elastic engaging hook is stuck in the latent end provided at the distal end of the engaging groove, preventing the recovery failure caused by the rotation of the capture head during the recovery of the inferior vena cava filter.

[0029] 4. By providing an end support groove at the end of the outer wall of the recovery tube and arranging an end support within the end support groove, it is possible to prevent the end of the recovery tube from contacting the blood vessel wall when the vena cava filter deflects, preventing the proliferation of vascular endothelium to block the orifice of the recovery tube lumen at the end face of the recovery tube, and ensuring that the vena cava filter can be smoothly recovered. Description of the Drawings

[0030] Figure 1 is a schematic structural diagram of an embodiment of the vena cava filter of the present application.

[0031] Figure 2 is Figure 1 a partial enlarged view of part A in

[0032] Figure 3 is a longitudinal sectional view of the position of the engaging hook groove in an embodiment of the vena cava filter of the present application.

[0033] Figure 4 is a longitudinal sectional view of the position of the end support groove in an embodiment of the vena cava filter of the present application.

[0034] Figure 5 is a transverse sectional view of the recovery tube in an embodiment of the vena cava filter of the present application.

[0035] Figure 6 is a schematic structural diagram of an embodiment of the capturing and recovery device for the vena cava filter of the present application.

[0036] Figure 7 is a schematic view of the capturing head part in an embodiment of the capturing and recovery device for the vena cava filter of the present application.

[0037] Figure 8 is a transverse sectional view of the capturing head in an embodiment of the capturing and recovery device for the vena cava filter of the present application.

[0038] Figure 9 is a longitudinal sectional view of the capturing head part in an embodiment of the capturing and recovery device for the vena cava filter of the present application.

[0039] Figure 10 is a schematic view of the combined state of an embodiment of the capturing and recovery device for the vena cava filter of the present application and an embodiment of the vena cava filter of the present application.

[0040] Description of the Reference Numerals: 1. Filter; 11. Distal connection part; 12. Distal elastic support; 121. Support wire; 13. Positioning part; 131. Positioning rod; 132. Positioning thorn; 14. Filter part; 141. Filter wire; 15. Proximal connection part; 2. Recovery tube; 21. Recovery tube cavity; 211. Engagement hook groove; 212. Elastic engagement hook; 213. Recovery guiding magnet; 22. End support groove; 221. Support cap groove; 23. End support; 231. Elastic support rod; 232. Support cap; 24. End face groove; 3. Recovery sleeve; 31. Recovery guiding surface; 4. Recovery guide wire; 41. Capture head; 411. Engagement groove; 412. Hidden end; 42. Capture guiding magnet; 5. Guide wire sleeve. Detailed implementation mode

[0041] The following will describe in detail the specific implementation mode of the present application with reference to the accompanying drawings. It should be understood that the specific implementation mode described herein is only used to illustrate and explain the present application, and is not used to limit the present application.

[0042] In the present application, unless otherwise stated, the orientation or positional relationship indicated by the orientation words such as "distal end, proximal end" is based on the orientation or positional relationship when the inferior vena cava filter and the inferior vena cava filter capture and recovery device of the present application are placed in the human blood vessel. Among them, the orientation word "distal end" refers to the end farther from the heart in the blood vessel, and the "proximal end" refers to the end closer to the heart. The description of the orientation or positional relationship of the inferior vena cava filter, the inferior vena cava filter capture and recovery device and their components of the present application is consistent with the actual orientation when they are placed in the human blood vessel.

[0043] In the description of the present application, it should be noted that, unless otherwise clearly defined and limited, the terms "set" and "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0044] An embodiment of the inferior vena cava filter of the present application is as Figures 1 to 3 shown, including a filter 1 and a recovery tube 2. The filter 1 is usually a net structure made of elastic metal wire. The filter 1 can be in two different states: retracted and released. In the retracted state, it is in a linear shape with a smaller diameter and can be placed at different positions in different blood vessels through a catheter, usually placed at the position distal to the renal vein in the inferior vena cava.

[0045] One end of the recovery tube 2 is fixedly connected to one end of the filter screen 1, usually fixed to the end of the distal end of the filter screen 1. A recovery tube cavity 21 is provided inside the recovery tube 2. The recovery tube cavity 21 opens on the end face of the distal end of the recovery tube 2 and is coaxially arranged with the recovery tube 2. A clamping hook groove 211 is provided on the inner wall of the recovery tube cavity 21. One end of the clamping hook groove 211 opens on the end face of the recovery tube 2, and the other end extends axially towards the filter screen 1. An elastic clamping hook 212 is arranged in the clamping hook groove 211. The elastic clamping hook 212 is usually made of a metal material with strong elasticity. One end of the elastic clamping hook 212 is fixed at the end position of the opening end of the clamping hook groove 211, and the other end extends towards the filter screen 1. And in the natural state, the end part is located in the recovery tube cavity 21 outside the clamping hook groove 211.

[0046] A recovery guiding magnet 213 is arranged deep on the side of the filter screen 1 in the recovery tube cavity 21. The recovery guiding magnet 213 is arranged at a certain distance from the end part of the elastic clamping hook 212.

[0047] The structure of arranging the elastic clamping hook 212 and the recovery guiding magnet 213 in the recovery tube cavity 21 is used to replace the traditional recovery hook arranged on the side wall of the recovery tube 2 of the vena cava filter, avoiding the situation that the side wall of the recovery tube 2 contacts the blood vessel wall due to the skew of the vena cava filter in the blood vessel, and the hyperplasia of the vascular endothelium on the side wall of the recovery tube 2 causes adhesion between the side wall of the recovery tube 2 and the blood vessel wall, resulting in difficulties in recovering the vena cava. The recovery guiding magnet 213 can attract the capture head of the capture and recovery device for recovering the vena cava filter, greatly facilitating the capture head to enter the recovery tube cavity 21 and form a coaxial connection with the recovery tube 2, which is beneficial to the traction recovery of the vena cava filter. The elastic clamping hook 212 arranged in the clamping hook groove 211 can elastically deform and retract into the clamping hook groove 211 when the capture head enters the recovery tube cavity 21, facilitating the capture head to pass through the opening of the recovery tube cavity 21, and making the elastic clamping hook 212 form a clamping on the capture head after the capture head passes through, forming a reliable connection between the capture head and the recovery tube 2, ensuring the reliable recovery of the vena cava filter by the capture and recovery device.

[0048] In some embodiments of the vena cava filter of the present application, such as Figures 1 to 3 shown, both the clamping hook groove 211 and the elastic clamping hook 212 are provided with a plurality of them. The plurality of clamping hook grooves 211 are evenly arranged circumferentially on the wall of the recovery tube cavity 21, and each elastic clamping hook 212 is arranged in one clamping hook groove 211. The plurality of evenly arranged elastic clamping hooks 212 can stably clamp the capture head from different circumferential positions of the capture head, ensuring the reliability of the connection between the capture head and the recovery tube 2 and the force stability of the recovery traction force received by the recovery tube 2.

[0049] In some embodiments of the vena cava filter of the present application, such as Figures 2 to 5As shown, a plurality of end support grooves 22 are provided on the outer sidewall of the recovery tube 2, and the plurality of end support grooves 22 are circumferentially spaced on the outer sidewall of the recovery tube 2. An end support 23 is provided in each end support groove 22. The end support 23 is made of a metal material with strong elasticity. One end of the end support 23 adjacent to the filter screen 1 is fixed in the end support groove 22. In the natural state, one end of the end support 23 adjacent to the opening of the recovery tube cavity 21 extends outward from the sidewall of the recovery tube 2 and supports outside the end support groove 22.

[0050] The end support groove 22 and the engaging hook groove 211 are arranged offset on the inner and outer sides of the recovery tube 2 to prevent the local sidewall thickness of the recovery tube 2 from being too thin and affecting the structural strength of the recovery tube 2.

[0051] After the vena cava filter is placed in the vena cava, if the vena cava filter is deflected in position under the pulsation of the accompanying artery or other external forces, the end support groove 22 supported on the outer side of the sidewall of the recovery tube 2 can abut against the blood vessel wall, preventing the blood vessel wall from contacting the end face of the recovery tube 2 and preventing the proliferation of vascular endothelium on the end face of the recovery tube 2 to block the opening of the recovery tube cavity 21. When subjected to external pressure, the end support groove 22 can elastically deform and be received in the end support groove 22, making the recovery tube 2 easier to enter the recovery sleeve of the capture recovery device and facilitating the recovery of the vena cava filter.

[0052] In a preferred embodiment of the vena cava filter of the present application, as Figures 2 to 4 shown, the end support 23 includes an elastic support rod 231 and a support cap 232. A support cap groove 221 is provided at one end of the end support groove 22. The elastic support rod 231 is arranged as a bent long strip-shaped rod, and the support cap 232 is arranged as a disc shape. The support cap 232 is connected to one end of the elastic support rod 231, and the outer side surface of the support cap 232 is spherical crown-shaped. The disc-shaped support cap 232 can increase the contact area between the end of the end support groove 22 and the blood vessel wall, effectively pushing the blood vessel wall away from the end of the recovery tube 2 while preventing the end of the end support groove 22 from damaging the blood vessel wall.

[0053] One end sidewall of the elastic support rod 231 is fixed to the bottom wall of the end support groove 22, and the other end extends out of the end support groove 22 and is fixedly connected to the support cap 232, usually integrally connected. The support cap 232 is arranged at a position corresponding to the outside of the support cap groove 221. When subjected to external force, the support cap 232 can be received in the support cap groove 221 through the elastic deformation of the elastic support rod 231.

[0054] In some embodiments of the vena cava filter of the present application, as Figures 2 to 4As shown, an end face groove 24 is provided on the end face of the recovery tube 2. The end face groove 24 is provided on the end face of the recovery tube 2 and is coaxially arranged with the recovery tube 2. The provision of the end face groove 24 can, when blood vessel endothelium proliferates on the end face of the recovery tube 2, block the growth of the blood vessel endothelium towards the opening of the recovery tube lumen 21, forming another line of defense against the blockage of the opening of the recovery tube lumen 21 by the blood vessel endothelium.

[0055] In some embodiments of the inferior vena cava filter of the present application, such as Figure 1 As shown, the filter net 1 includes a distal connection part 11, a distal elastic support 12, a positioning part 13, a filter net part 14, and a proximal connection part 15. The distal elastic support 12 includes a plurality of support metal wires 121. In this embodiment, it includes six support metal wires 121. One ends of the six support metal wires 121 are connected to each other in pairs to form three combined support wires, and the ends of the three combined support wires are connected to each other to form the distal connection part 11. The other ends of the plurality of support metal wires 121 are connected to the end of one end of the positioning part 13.

[0056] The positioning part 13 includes a plurality of positioning rods 131. In this embodiment, it includes six positioning rods 131. The outer sides of the six positioning rods 131 are set to be arc-shaped. One ends of the six positioning rods 131 are respectively connected to the ends of one support metal wire 121, and the other ends are connected to the filter net part 14.

[0057] The filter net part 14 includes a plurality of filter net metal wires 141. In this embodiment, it includes twelve filter net metal wires 141. One ends of the twelve filter net metal wires 141 are connected to each other in pairs to form six combined filter net wires, and one ends of the six combined filter net wires are connected to each other to form the proximal connection part 15. The other ends of two filter net metal wires 141 in each combined filter net wire are respectively cross-connected to the other end of one filter net metal wire 141 in an adjacent combined filter net wire and are commonly connected to the other end of the same positioning rod 131, so that the twelve filter net metal wires 141 are cross-connected to form a filter net structure.

[0058] In the free state, while each support metal wire 121 extends from the distal connection part 11 towards the proximal connection part 15, it extends in different peripheral directions; at the same time, while each filter net metal wire 141 extends from the proximal connection part 15 towards the distal connection part 11, it extends in different peripheral directions, supporting the positioning rods 131 at different circumferential positions around the axis formed by the connection of the distal connection part 11 and the proximal connection part 15, so that the plurality of positioning rods 131 all extend along the direction parallel to the axis formed by the connection of the distal connection part 11 and the proximal connection part 15.

[0059] The support wire 121 and the filter wire 141 are made of elastic metal material or memory metal material. Through the elastic deformation of the support wire 121 and the filter wire 141, the vena cava filter of the present application can be gathered near the axis formed by the distal connection part 11 and the proximal connection part 15, forming a strip-shaped entry into the lumen of the sleeve, so that the vena cava filter can be placed in a suitable position in the vena cava through the sleeve. After the placement is completed, the sleeve is pulled out, and the multiple positioning rods 131 are supported at different circumferential positions in the vena cava under the elastic force of the support wire 121 and the filter wire 141, and the position stability of the vena cava filter in the vena cava is improved by using multiple mutually parallel positioning rods 131. The support wire 121 is located at the distal end of the vena cava, and the small number of support wires 121 makes the gaps between the support wires 121 larger, which is conducive to the venous thrombus entering the interior of the vena cava filter through the gaps between the support wires 121. The filter wires 141 are located at the proximal end of the vena cava. A large number of filter wires 141 and the cross-connections between the filter wires 141 result in smaller gaps between the filter wires 141, which is beneficial for preventing the passage of venous thrombi, thereby blocking the venous thrombi and collecting them in the vena cava filter.

[0060] A positioning thorn 132 is provided on the positioning rod 131. The positioning thorn 132 is usually provided on the outside of the positioning rod 131, close to one end of the distal connection part 11, and inclined toward the proximal connection part 15. The positioning thorn 132 can be fixed on the blood vessel wall of the vena cava, thereby improving the position stability of the strong venous filter in the vena cava and preventing the vena cava filter from moving in the blood vessel under the impact of the blood flow in the vena cava.

[0061] The recovery tube 2 is fixedly connected to one end of the distal connection part 11 or the proximal connection part 15, and is usually fixedly connected to one end of the distal connection part 11. When the vena cava filter is pulled toward the recovery sleeve by the capture recovery device, the end of the recovery sleeve squeezes the support wire 121 or the filter wire 141, so that the support wire 121, the positioning rod 131 and the filter wire 141 are successively gathered near the axis formed by the distal connection part 11 and the proximal connection part 15 due to the elastic deformation of the support wire 121 and the filter wire 141, forming a strip-like shape and entering the lumen of the recovery sleeve, and the recovery of the vena cava filter of the present application is completed by pulling out the recovery catheter from the vena cava.

[0062] The vena cava filter capture and recovery device of the present application is used to recover the vena cava filter of any embodiment of the present application.

[0063] An embodiment of the vena cava filter capture and recovery device of the present application is as follows: Figure 6 and Figure 7As shown, it includes a recovery sleeve 3 and a recovery guide wire 4. The recovery guide wire 4 is inserted into the lumen of the recovery sleeve 3. The recovery guide wire 4 is usually made of an inert metal material. At one end of the recovery guide wire 4, a capture head 41 is provided. The diameter of the capture head 41 is larger than that of the recovery guide wire 4, and the recovery guide wire 4 is coaxially arranged with the capture head 41. A guide wire sleeve 5 can also be provided outside the recovery guide wire 4. The setting of the guide wire sleeve 5 is beneficial to driving the rotation of the capture head 41 from the outer end of the recovery guide wire 4.

[0064] The guide wire sleeve 5 can move together with the recovery guide wire 4 in the recovery sleeve 3, control the capture head 41 to extend out of the end of the recovery sleeve 3, enter the recovery lumen 21 of the vena cava filter, and capture and recover the vena cava filter. The setting of the guide wire sleeve 5 is beneficial to driving the rotation of the capture head 41 by rotating the recovery guide wire 4. At the end of the capture head 41, a capture guiding magnet 42 is provided. The capture guiding magnet 42 can be fixedly connected to the end of the capture head 41 using a permanent magnet, or the capture head 41 can be made of a magnetic material, and then the capture head 41 is magnetized after being formed to obtain a capture head 41 of a permanent magnet. Among them, the magnetic poles of the ends of the capture guiding magnet 42 and the recovery guiding magnet 213 that are close to each other are opposite.

[0065] On the side wall of the capture head 41, a clamping groove 411 is provided. The clamping groove 411 is arranged on the side wall of the capture head 41 in a direction parallel to the axial direction of the capture head 41. The number and position of the clamping grooves 411 correspond to the clamping hook grooves 211 on the side wall of the recovery lumen 21.

[0066] When recovering the vena cava filter, the recovery sleeve 3 is inserted into the vena cava percutaneously, and the recovery guide wire 4 or the guide wire sleeve 5 is controlled to make the capture head 41 extend out of the recovery sleeve 3 and move to the vicinity of the end of the recovery tube 2. The capture head 41 will enter the recovery lumen 21 under the magnetic attraction between the recovery guiding magnet 213 and the capture guiding magnet 42. The elastic clamping hook 212 is pressed into the clamping hook groove 211 by the side wall of the capture head 41, so that the capture guiding magnet 42 is attracted to the recovery guiding magnet 213. Rotate the recovery guide wire 4 to make the capture head 41 rotate in the recovery lumen 21 until the elastic clamping hook 212 snaps into the clamping groove 411 under the action of elastic force, forming a connection between the capture head 41 and the recovery tube 2. At this time, hold the recovery sleeve 3 and pull out the recovery guide wire 4, and the recovery tube 2, the distal connecting part 11 of the filter net 1, the distal elastic support 12, the positioning part 13, the filter net part 14, and the proximal connecting part 15 can be sequentially drawn into the recovery sleeve 3 in turn to realize the recovery of the vena cava filter. The state of the vena cava filter capture and recovery device of the present application after being connected to the vena cava filter is as Figure 10 shown.

[0067] In some embodiments of the vena cava filter capture and recovery device of the present application, such asFigure 7 and Figure 8 As shown in Figure 8 , on one side of the engaging groove 411 in the circumferential direction of the capture head 41, the side surface is set as a plane extending in the axial direction, and on the other side, the side surface is set as a smooth curved surface or an inclined plane extending from the bottom of the engaging groove 411 to the outer side surface of the capture head 41.

[0068] After the elastic engaging hook 212 is engaged in the engaging groove 411, the recovery guide wire 4 can be rotated in the reverse direction to make the capture head 41 rotate in the reverse direction in the recovery lumen 21, so that the elastic engaging hook 212 is disengaged from the engaging groove 411 and is pressed into the engaging groove 411 by the outer side wall of the capture head 41, enabling the capture head 41 to be easily separated from the recovery tube 2. This makes the vena cava filter capture and recovery device of the present application capable of placing a vena cava filter in the vena cava and removing the recovery guide wire 4 after the positioning thorn 132 positions the filter mesh 1; or in special cases where there is a high degree of adhesion between the filter mesh 1 and the vena cava, removing the recovery guide wire 4 and inserting an interventional dissection instrument to perform dissection between the filter mesh 1 and the vena cava wall.

[0069] In a preferred embodiment of the vena cava filter capture and recovery device of the present application, as Figure 7 and Figure 9 shown, one end of the engaging groove 411 opens at the distal end face of the capture head 41, that is, the end face connected to the recovery guide wire 4, and the other end terminates at a region of the side wall of the capture head 41 adjacent to the proximal end face or adjacent to the capture guiding magnet 42 to form a blind end. A latent end 412 is provided at the bottom of the blind end of the engaging groove 411. When the recovery guide wire 4 is pulled outward, the capture head 41 can be pulled toward the distal end, so that the end of the elastic engaging hook 212 is engaged in the latent end 412, preventing the elastic engaging hook 212 from being disengaged from the engaging groove 411 due to accidental rotation of the recovery guide wire 4 during the process of pulling the vena cava filter outward.

[0070] In some embodiments of the vena cava filter capture and recovery device of the present application, as Figure 9 shown, the side wall of the lumen in the proximal end region of the recovery sleeve 3 is set as a recovery guiding surface 31 similar to a trumpet shape. The trumpet-shaped recovery guiding surface 31 can form a guiding and squeezing effect on the end of the recovery tube 2, the end of the support cap 232, the support wire 121, or the filter mesh wire 141, which is beneficial to the accommodation of the recovery tube 2 and the filter mesh 1 in the recovery sleeve 3.

[0071] In the description of the present application, the descriptions referring to terms such as "one embodiment", "some embodiments", "preferred embodiments", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples.

[0072] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A vena cava filter, comprising a filter screen (1) and a recovery tube (2), wherein the recovery tube (2) is arranged at the end of the filter screen (1), characterized in that: The recovery tube (2) is provided with a recovery tube cavity (21) opening at the end surface of the recovery tube (2), and a snap hook groove (211) is provided on the inner wall of the end of the recovery tube cavity (21), and an elastic snap hook (212) is provided in the snap hook groove (211), one end of the elastic snap hook (212) is fixed in the snap hook groove (211), and the other end extends in the direction of the filter screen (1), and the end extends into the recovery tube cavity (21), and a recovery guide magnet (213) is provided in the recovery tube cavity (21), and the recovery guide magnet (213) is arranged on a side of the snap hook groove (211) adjacent to the filter screen (1), and is spaced apart from the snap hook groove (211).

2. The vena cava filter according to claim 1, characterized in that: The snap hook grooves (211) and the elastic snap hooks (212) are both provided in plurality, and the plurality of snap hook grooves (211) are evenly arranged in the circumferential direction of the wall of the recovery tube cavity (21), and each of the elastic snap hooks (212) is arranged in one of the snap hook grooves (211).

3. The vena cava filter according to claim 1, characterized in that: A plurality of end support grooves (22) are provided on the outer wall of the recovery pipe (2), and the plurality of end support grooves (22) are arranged at intervals in the circumferential direction of the outer wall of the recovery pipe (2), and an end support (23) is provided in each of the end support grooves (22), one end of the end support (23) is fixed in the end support groove (22), and the other end is elastically supported outside the end support groove (22).

4. The vena cava filter according to claim 3, characterized in that: The end support (23) comprises an elastic support rod (231) and a support cap (232); one end of the end support groove (22) is provided with a support cap groove (221); one end of the elastic support rod (231) is fixed to the bottom wall of the end support groove (22); the other end is fixedly connected to the support cap (232); the support cap (232) is arranged at a position corresponding to the support cap groove (221); and the support cap (232) can be accommodated in the support cap groove (221) through elastic deformation of the elastic support rod (231).

5. The vena cava filter according to claim 1, characterized in that: An end surface groove (24) is provided on the end surface of the recovery pipe (2).

6. The vena cava filter according to any one of claims 1 to 5, characterized in that: The filter screen (1) comprises a distal connection portion (11), a distal elastic support (12), a positioning portion (13), a filter screen portion (14) and a proximal connection portion (15); the distal elastic support (12) comprises a plurality of support metal wires (121); the positioning portion (13) comprises a plurality of positioning rods (131); one ends of the plurality of support metal wires (121) are mutually connected to form the distal connection portion (11); the other ends are respectively fixedly connected to one end of the positioning rods (131); the filter screen portion (14) comprises a plurality of filter screen metal wires (141); one ends of the plurality of filter screen metal wires (141) are mutually connected to form the proximal connection portion (15); the other ends are mutually connected to one end of the positioning rods (131); Cross-connected to the other end of the positioning rod (131), in a free state, a plurality of the support wires (121) extend from the distal connection part (11) to different directions of the periphery, and a plurality of the filter wires (141) extend from the proximal connection part (15) to different directions of the periphery, so as to support the positioning rod (131) at different circumferential positions around the distal connection part (11) and the proximal connection part (15), and the plurality of the positioning rods (131) all extend in the axial direction, and a positioning thorn (132) is provided on the positioning rod (131), and the distal connection part (11) or the proximal connection part (15) is fixedly connected to one end of the recovery pipe (2).

7. A vena cava filter capture and recovery device, used for recovering the vena cava filter according to any one of claims 1 to 6, characterized in that: The invention comprises a recovery sleeve (3) and a recovery guide wire (4), wherein one end of the recovery guide wire (4) is provided with a capture head (41), the recovery guide wire (4) is arranged in the recovery sleeve (3), and the capture head (41) can extend out of the recovery sleeve (3) and enter into the recovery tube cavity (21), the capture head (41) comprises a capture guide magnet (42), the magnetism of the capture guide magnet (42) and the recovery guide magnet (213) at the opposite end are opposite, and the side wall of the capture head (41) is provided with a snap-fit ​​groove (411), and the snap-fit ​​groove (411) is arranged corresponding to the snap-fit ​​hook groove (211).

8. The vena cava filter capture and recovery device according to claim 7, characterized in that: One circumferential side surface of the engaging groove (411) is arranged as a plane extending in the axial direction, and the other circumferential side surface is arranged as a smooth curved surface extending from the groove bottom to the outer peripheral surface of the capturing head (41).

9. The vena cava filter capture and recovery device according to claim 8, characterized in that: One end of the engaging groove (411) opens at the distal end surface of the capturing head (41), and the other end terminates at an area adjacent to the proximal end surface, and a latent end (412) is provided at the end.

10. The vena cava filter capture and recovery device according to claim 7, characterized in that: A recovery guide surface (31) is provided at the proximal end of the lumen of the recovery sleeve (3).

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