filter

Abstract

This invention relates to a filter comprising a connected filter body, a corrective component, and a retrieval hook. The circumferential outer surface of the filter body is used to adhere to and support the inner wall of a blood vessel. The corrective component has a support surface for adhering to and supporting the inner wall of the blood vessel. The proximal end of the retrieval hook has a hook portion for cooperating with a capture ring to retrieve the lowered filter. Along the axial direction of the filter, the support surface is located between the filter body and the hook portion. Along the radial direction of the filter, the circumferential outer surface of the hook portion is closer to the central axis of the filter than the support surface. According to the filter proposed in this invention, the circumferential outer surface of the filter body and the support surface of the corrective component jointly support the inner wall of the blood vessel, preventing the hook portion of the retrieval hook from contacting the inner wall of the blood vessel, thereby preventing endothelial overgrowth of the hook portion and facilitating filter removal.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and more particularly to a filter. Background Technology

[0002] Pulmonary embolism is an acute condition with high morbidity and mortality. In the United States, there are 570,000 to 630,000 cases of symptomatic pulmonary embolism each year, of which 200,000 result in death. Although systemic anticoagulation therapy can achieve some efficacy, there is still a 3% to 20% chance of recurrent pulmonary embolism. Moreover, anticoagulation therapy itself has a 26% complication rate, of which 5% to 12% are fatal. Some patients cannot tolerate anticoagulation therapy, such as those with acute bleeding, gastrointestinal ulcers, primary or metastatic tumors (especially intracranial tumors), pregnancy, or before surgical treatment.

[0003] In the history of preventing pulmonary embolism, humans have used methods such as heparin therapy and inferior vena cava ligation, but all of them have some obvious drawbacks. For example, 10-26% of patients undergoing heparin therapy experience pulmonary embolism again due to collateral circulation in the lower limbs and pelvis. In addition, venous ligation can hinder venous blood return to the heart and reduce cardiac output. Furthermore, 7-50% of patients experience pulmonary embolism again due to collateral circulation.

[0004] Starting in the early 1960s, various specialized inferior vena cava devices emerged to address these issues, such as inferior vena cava clips, but the complication rate was as high as 27%. Later, the development of interventional radiology provided a better solution, using minimally invasive non-surgical cannulation techniques to insert vena cava filters, significantly improving the effectiveness of clinical applications.

[0005] In current clinical applications, after implantation, the vena cava filter tends to tilt within the blood vessel over time. This can cause the retrieval hook component of the filter to adhere tightly to the inner wall of the blood vessel, or even lead to endothelial overgrowth, making the filter difficult to remove. Summary of the Invention

[0006] The purpose of this invention is to at least solve the problem of endothelial erosion of the retrieval hook due to it adhering tightly to the inner wall of the blood vessel when the filter is tilted. To address the shortcomings of the prior art, a filter is provided.

[0007] The technical problem solved by this invention is achieved through the following technical solution:

[0008] According to a first aspect of the present invention, a filter is provided, the filter comprising a connected filter body, a corrective component, and a retrieval hook, wherein the circumferential outer surface of the filter body is used to adhere to and support the inner wall of a blood vessel, the corrective component has a support surface for adhering to and supporting the inner wall of the blood vessel, the retrieval hook is provided with a hook portion for cooperating with a capture ring to retrieve the filter, the support surface is located between the filter body and the hook portion along the axial direction of the filter, and the circumferential outer surface of the hook portion is closer to the central axis of the filter than the support surface along the radial direction of the filter.

[0009] In some embodiments of the present invention, the correction component includes a plurality of support units connected to the recovery hook and arranged sequentially around the central axis. Along the radial direction of the filter, the end face of the support unit opposite to the central axis defines the support surface, and the plurality of support surfaces are arranged sequentially along the circumference of the filter.

[0010] In some embodiments of the present invention, the support unit includes at least two support rods arranged sequentially along the axial direction of the filter, with the ends of the two support rods away from the central axis connected to each other, and adjacent support rods arranged at an included angle.

[0011] The recycling hook includes a first tube and a second tube. The proximal end of the filter body is connected to the distal end of the first tube. The second tube is provided with the hook portion. The distal end of the support unit is connected to the proximal end of the first tube, and the proximal end of the support unit is connected to the distal end of the second tube.

[0012] In some embodiments of the present invention, the at least two support rods include a first support rod and a second support rod, one end of the first support rod is connected to the proximal end of the first tube, the other end of the first support rod is connected to one end of the second support rod, and the other end of the second support rod is connected to the distal end of the second tube.

[0013] Alternatively, the at least two support rods may include two first support rods, two second support rods, and one third support rod. One end of each first support rod is connected to the proximal end of the first tube, and the other end of each first support rod is connected to one end of a second support rod. The other ends of the two second support rods are connected to one end of the third support rod, and the other end of the third support rod is connected to the distal end of the second tube. A first plane is drawn along the radial direction of the filter, and the projections of the two first support rods, the two second support rods, and the third support rod onto this first plane are staggered between any two of them.

[0014] In some embodiments of the present invention, all the support rods enclose a support space, and the support rods are provided with a first cutting edge extending along their own length direction, the first cutting edge being disposed facing the interior of the support space.

[0015] In some embodiments of the present invention, the filter further includes a cutting component connected to the recycling hook. The cutting component includes a plurality of cutting elements arranged sequentially around the central axis. Along the radial direction of the filter, the end of the cutting element facing away from the central axis is closer to the central axis than the support surface.

[0016] In this configuration, a second plane is formed along the radial direction of the filter, and the projections of the plurality of support units and the plurality of cutting elements on the second plane are alternately arranged along the circumference of the filter.

[0017] In some embodiments of the present invention, the cutting member is located between the hook and the straightening member along the axial direction of the filter; or, along the circumferential direction of the filter, a cutting member is provided between any two adjacent support units.

[0018] In some embodiments of the present invention, the cutting element includes at least two cutting rods connected sequentially along the axial direction of the filter, and any two adjacent cutting rods are arranged at an included angle.

[0019] All the cutting rods enclose a cutting space, and each cutting rod has a second cutting edge extending along its own length, with the second cutting edge facing outwards from the cutting space.

[0020] In some embodiments of the present invention, the corrective component further includes a connecting sleeve, which is sleeved over the recovery hook, and the plurality of support units are respectively connected to the connecting sleeve;

[0021] The support unit includes multiple support rods, which are connected to form a grid structure. The multiple support units are connected sequentially along the circumference of the filter, so that the correction component forms a mesh structure with multiple grid structures.

[0022] In some embodiments of the present invention, the support rod is configured as an arc-shaped rod, with the support rod arching towards the proximal end in the direction from the proximal end to the distal end;

[0023] And / or, along the radial direction of the filter, the end of the support rod opposite to the central axis is provided with a support portion, the outer surface of the support portion defines the support surface, and the outer surface of the support portion is configured as an arc-shaped convex surface.

[0024] In some embodiments of the present invention, the corrective component includes a mesh structure woven from braided filaments, the circumferential outer surface of the mesh structure defining the support surface;

[0025] The recycling hook includes a first tube and a second tube. The proximal end of the filter body is connected to the distal end of the first tube. The second tube is provided with the hook portion. The distal end of the mesh structure is connected to the proximal end of the first tube, and the proximal end of the mesh structure is connected to the distal end of the second tube.

[0026] In some embodiments of the present invention, the filter body, the correction component, and the recovery hook are coaxially arranged;

[0027] Along the axial direction of the filter, the distance from the proximal end of the hook to the proximal end of the support surface is L1, and the distance from the proximal end of the hook to the proximal end of the circumferential outer surface of the filter body is L2.

[0028] Along the radial direction of the filter, the distance from the support surface to the central axis is R1, and the radius of the filter body is R2, wherein L1 / R1 < L2 / R2.

[0029] In some embodiments of the present invention, the filter body includes a filter screen and a plurality of support branches, the support branches extending along the axial direction of the filter, the plurality of support branches being arranged sequentially along the circumferential direction of the axial direction of the filter and defining the circumferential outer surface of the filter body, and the filter screen being connected to the distal end of each of the support branches;

[0030] The corrective component includes a plurality of support rods, each support rod having a first end and a second end. The first end of each support rod is connected to the proximal end of a support branch, and the second end of each support rod is connected to the distal end of the retrieval hook. The second end is positioned closer to the distal end than the first end.

[0031] According to the filter proposed in this invention, when the filter is tilted inside the blood vessel, the circumferential outer surface of the hook is closer to the central axis of the filter than the supporting surface. That is, the supporting surface protrudes towards the inner wall of the blood vessel compared to the hook. Thus, the circumferential outer surface of the filter body and the supporting surface of the correction component jointly support the inner wall of the blood vessel, preventing the hook of the retrieval hook from contacting the inner wall of the blood vessel, thereby preventing endothelial overgrowth of the hook of the retrieval hook and facilitating the removal of the filter. Attached Figure Description

[0032] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. Wherein:

[0033] Figure 1a This is a schematic diagram of the filter structure from the main viewpoint of Embodiment 1 of the present invention;

[0034] Figure 1b This is a schematic diagram of the filter structure from a bottom-view perspective according to Embodiment 1 of the present invention;

[0035] Figure 2a It shows Figure 1a A magnified view of part A in the middle;

[0036] Figure 2b This is a structural schematic diagram of the cross-section of the support rod in Embodiment 1 of the invention;

[0037] Figure 3a This is a schematic diagram of the structure of the correction component and the retrieval hook from the main viewpoint of Embodiment 1 of the present invention;

[0038] Figure 3b This is a schematic diagram of the corrective component and the recovery hook from the upper left perspective of Embodiment 1 of the present invention;

[0039] Figure 3c This is a top-view structural diagram of the correction component and the retrieval hook according to Embodiment 1 of the present invention;

[0040] Figure 4a This is a schematic diagram of the filter structure from the main viewpoint in Embodiment 2 of the present invention;

[0041] Figure 4b This is a schematic diagram of the filter structure from a bottom-view perspective according to Embodiment 2 of the present invention;

[0042] Figure 5a This is a schematic diagram of the structure of the correction component and the retrieval hook from the upper left perspective of Embodiment 2 of the present invention;

[0043] Figure 5b This is a top-view structural diagram of the correction component and the recovery hook according to Embodiment 2 of the present invention;

[0044] Figure 6a This is a schematic diagram of the filter structure from the main viewpoint in the first embodiment of the present invention;

[0045] Figure 6b This is a schematic diagram of the filter structure from a bottom-view perspective according to the first embodiment of the present invention, in Example 3 of the present invention.

[0046] Figure 7a This is a partial structural diagram of the filter from the upper left perspective of the first embodiment of the present invention;

[0047] Figure 7bThis is a schematic diagram of the corrective component and the recovery hook from a bottom-view perspective in the first embodiment of the present invention, according to Example 3 of the present invention.

[0048] Figure 8 This is a schematic diagram of the filter structure from the main viewpoint in the second embodiment of the present invention;

[0049] Figure 9a This is a schematic diagram of the corrective component and the recovery hook from the upper left perspective of the second embodiment of the present invention;

[0050] Figure 9b This is a schematic diagram of the corrective component and the recovery hook from the main viewpoint of the second embodiment of the present invention;

[0051] Figure 9c It shows Figure 9b A schematic diagram of a partial cross-sectional structure of the BB section;

[0052] Figure 10a This is a schematic diagram of the filter structure from the main viewpoint in Embodiment 4 of the present invention;

[0053] Figure 10b This is a partial structural diagram of the filter from the upper left perspective of Embodiment 4 of the present invention;

[0054] Figure 11a This is a schematic diagram of the filter structure from the main viewpoint in Embodiment 5 of the present invention;

[0055] Figure 11b This is a schematic diagram of the filter structure from a top view of Embodiment 5 of the present invention;

[0056] Figure 12 This is a schematic diagram of the filter structure from the main viewpoint in Embodiment 6 of the present invention;

[0057] Figure 13 This is a schematic diagram of the filter of the present invention housed inside the conveyor;

[0058] Figure 14 This is a schematic diagram of the structure of the filter of the present invention being released from the conveyor;

[0059] Figure 15 This is a schematic diagram showing the tilting of the filter of the present invention after it is implanted into a vein.

[0060] The labels in the attached diagram are as follows:

[0061] 100. Filter; 1001. Central axis;

[0062] 10. Filter body; 11. Filter screen; 111. Condensation section; 112. First filter branch; 113. Second filter branch; 12. Support branch; 13. Connecting rod; 14. Fixing anchor; 15. Receiving groove;

[0063] 20. Correcting component; 201. Support surface; 21. Support unit; 211. Support rod; 21101. First end; 21102. Second end; 2111. First support rod; 2112. Second support rod; 2113. Third support rod; 2101. Support space; 2102. First cutting edge; 212. Support part;

[0064] 22. Connecting sleeve; 210. Mesh structure;

[0065] 23. Network disk structure; 24. Coating;

[0066] 30. Retrieval hook; 31. First tube body; 32. Second tube body; 301. Hook part;

[0067] 40. Cutting component; 41. Cutting part; 411. First cutting rod; 412. Second cutting rod; 401. Cutting space; 402. Second cutting edge;

[0068] 200, delivery device; 300, blood vessel. Detailed Implementation

[0069] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0070] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0071] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0072] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure rotates, then an element described as "below other elements or features" or "below other elements or features" will subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations.

[0073] It should be noted that the terms "distal" and "proximal" are used as directional terms, which are commonly used in the field of interventional medical devices. "Distal" refers to the end furthest from the operator during the procedure, while "proximal" refers to the end closest to the operator. Axial direction refers to the direction parallel to the line connecting the center of the distal and proximal ends of the medical device; radial direction refers to the direction perpendicular to the aforementioned axial direction.

[0074] Please combine Figure 1a , Figure 4a , Figure 6a , Figure 10a , Figure 11a , Figure 12 and Figure 15 As shown, the present invention proposes a filter 100, particularly an inferior vena cava filter, the filter 100 including a connected filter body 10, a correction component 20 and a retrieval hook 30.

[0075] In detail, the filter body 10 includes a filter screen 11 and multiple support branches 12. The filter screen 11 is used to filter emboli in the blood and prevent them from entering other arteries, such as the pulmonary artery, with the blood. For example, the filter screen 11 can be formed by connecting six rhomboid mesh structures 210 sequentially along the circumference of the filter 100 to form an umbrella-shaped structure with multiple meshes. The support branches 12 are rod-shaped structures, with the proximal end of each rhomboid mesh structure connected to the distal end of a support branch 12. The extension direction of the support branches 12 is parallel to the axial direction of the filter 100. The six support branches 12 are arranged sequentially at intervals along the circumference of the filter 100 and are arranged in a ring around the central axis 1001 of the filter 100. After the filter 100 is implanted into the blood vessel 300, the support branches 12 are used to abut against the inner wall of the blood vessel 300 to keep the filter 100 stable inside the blood vessel 300, so as to ensure that the filter screen 11 can filter emboli in the blood for a long time.

[0076] Furthermore, the filter body 10 also includes a plurality of connecting rods 13, the proximal end of each support branch 12 being connected to the distal end of a connecting rod 13, and the proximal ends of all connecting rods 13 being connected to the distal end of the recovery hook 30. From the distal end to the proximal end, the connecting rods 13 extend obliquely toward the direction close to the central axis 1001, so that the proximal end of the filter body 10 forms a converging structure with the outer diameter gradually decreasing from the distal end to the proximal end, which facilitates the retraction of the filter body 10 into the sheath during the retrieval of the filter 100.

[0077] For ease of manufacturing and recycling, the filter screen 11 is integrally formed with the support branch 12 and the connecting rod 13. The filter body 10 is made of any suitable material known in the art, such as a polymer, a flexible permeable membrane made of metal, etc. In addition, the mesh structure of the filter screen 11 should have a surface area and pore size that allow sufficient blood volume to pass through to maintain normal blood pressure, and the design should avoid pressure buildup as much as possible to prevent mesh rupture.

[0078] In some embodiments, the filter body 10 is made of a non-radiotransparent metallic material, specifically including one or more of nickel-titanium alloys, cobalt-chromium alloys, platinum-chromium alloys, and titanium. These materials, with their excellent biocompatibility, mechanical properties, and radiation impermeability, provide a solid guarantee for the filter 100 to function stably and safely in the complex physiological environment of the human body over a long period.

[0079] like Figure 3a and Figure 3bAs shown, the recovery hook 30 is configured as a circular tube structure, and the recovery hook 30 is provided with a hook part 301. The hook part 301 is a tube groove cut out on the circumferential outer surface of the circular tube structure. The tube groove forms an opening on the circumferential outer surface of the recovery hook 30, and the tube groove forms two side walls and a bottom wall connecting the two side walls on the recovery hook 30. The bottom wall extends along the axial direction of the filter 100, and the side walls are set at an angle with the central axis 1001 of the filter 100. From the bottom wall to the opening, the side walls extend inclined towards the side closer to the far end. This arrangement is beneficial to the recovery of the filter 100.

[0080] The corrective component 20 is connected to the filter body 10 or the retrieval hook 30. The corrective component 20 has a support surface 201 for adhering to and supporting the inner wall of the blood vessel. Along the axial direction of the filter 100, the support surface 201 is located between the filter body 10 and the hook portion 301. Along the radial direction of the filter 100, the circumferential outer surface of the hook portion 301 is closer to the central axis 1001 of the filter 100 than the support surface 201. That is, the support surface 201 protrudes towards the inner wall of the blood vessel compared to the hook portion 301. When the tilting corrective vena cava filter tilts, the support surface 201 of the tilting corrective component can react quickly and first adhere tightly to the inner wall of the blood vessel 300, avoiding the retrieval hook 30 from adhering to the blood vessel wall and eliminating the risk of tissue endothelium crawling onto the retrieval hook 30. This ensures that the grab ring on the vena cava filter retrieval device can be smoothly put into the hook portion 301 of the retrieval hook 30, creating favorable conditions for the subsequent smooth removal of the filter 100.

[0081] In this invention, the virtual central axis 1001 of the recovery hook 30 is used as the central axis 1001 of the filter 100.

[0082] Furthermore, the filter body 10, the straightening component 20, and the recovery hook 30 are coaxially arranged, meaning that the central axis 1001 of the filter body 10, the central axis 1001 of the straightening component 20, and the central axis 1001 of the recovery hook 30 coincide. Along the axial direction of the filter 100, the distance from the proximal end of the hook 301 to the proximal end of the support surface 201 is L1, and the distance from the proximal end of the hook 301 to the proximal end of the circumferential outer surface of the filter body 10 is L2. Along the radial direction of the filter 100, the distance from the support surface 201 to the central axis 1001 is R1, and the radius of the filter body 10 is R2, where L1 / R1 < L2 / R2. Since both the circumferential outer surface of the filter body 10 and the support surface 201 of the corrective component 20 are used to abut against the inner wall of the blood vessel 300, when the filter 100 tilts inside the blood vessel 300, based on the fact that the circumferential outer surface of the filter body 10 and the support surface 201 of the corrective component 20 simultaneously support the inner wall of the vein 300, the proximal end of the circumferential outer surface of the filter body 10 and the support surface 201 of the corrective component 20 can provide a receiving space for the hook portion 301 of the retrieval hook 30. The receiving space is at least the space enclosed by all the lines connecting the proximal end of the circumferential outer surface of the filter body 10 and the support surface 201 of the corrective component 20. By ensuring that L1 / R1 < L2 / R2, the hook portion 301 of the retrieval hook 30 is necessarily located inside the receiving space, thereby preventing the hook portion 301 of the retrieval hook 30 from contacting the inner wall of the blood vessel 300.

[0083] It should be noted that, since the inner wall of the vein 300 has a certain degree of elasticity and toughness, and in order to fix the filter 100 inside the vein 300, the diameter of the filter 100 is generally slightly larger than or equal to the inner diameter of the vein 300. Therefore, when the filter 100 is implanted into the vein 300, the inner wall of the vein 300 is in a state of tension under the support of the filter 100. In this state, the outline of the inner wall of the vein 300 is essentially coincident with the line connecting the proximal end of the circumferential outer surface of the filter body 10 and the support surface 201 of the correction component 20. Therefore, the line connecting the proximal end of the circumferential outer surface of the filter body 10 and the support surface 201 of the correction component 20 can be used as the virtual outline of the inner wall of the vein 300. The continuously defined accommodating space can be regarded as the area located inside the vein 300 and not in contact with the inner wall of the vein 300. In summary, the L1 / R1 < L2 / R2 configuration ensures that the hook portion 301 of the retrieval hook 30 is located inside the accommodating space, meaning that the hook portion 301 of the retrieval hook 30 is in an area that will not come into contact with the inner wall of the blood vessel 300, thereby preventing the retrieval hook 30 from contacting the inner wall of the blood vessel 300.

[0084] The technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0085] Example 1

[0086] In this embodiment, please refer to Figures 1a to 3c As shown, the recycling hook 30 includes a first tube 31 and a second tube 32. The proximal end of the filter body 10 (that is, the proximal end of all connecting rods 13) is connected to the distal end of the first tube 31, and the second tube 32 is provided with a hook 301.

[0087] like Figure 1a and Figure 1b As shown, the correction component 20 includes multiple support units 21, which are arranged sequentially around the central axis. Along the radial direction of the filter 100, the end face of the support unit 21 facing away from the central axis defines a support surface 201. The multiple support surfaces 201 are arranged sequentially along the circumference of the filter 100 and are arranged in a ring.

[0088] like Figure 3a and Figure 3b As shown, the support unit 21 includes at least two support rods 211. Along the axial direction of the filter 100, at least two support rods 211 are connected in sequence, and any two adjacent support rods 211 are arranged at an included angle. Specifically, at least two support rods 211 include a first support rod 2111 and a second support rod 2112. One end of the first support rod 2111 is connected to the proximal end of the first tube 31, and the other end of the first support rod 2111 is connected to one end of the second support rod 2112. The other end of the second support rod 2112 is connected to the distal end of the second tube 32. Along the axial direction of the filter 100, the first support rod 2111 and the second support rod 2112 are inclined relative to the central axis 1001 of the filter 100, and the first support rod 2111 and the second support rod 2112 are set at an angle. The value of the angle γ between the first support rod 2111 and the second support rod 2112 is in the range of 20° to 40°. For example, γ can be 20°, 22°, 25°, 26°, 28°, 29°, 30°, 31°, 33°, 35°, 36°, 38°, 39°, 40°, etc. The angled arrangement of the first support rod 2111 and the second support rod 2112 provides better support, ensuring that the support unit 21 can effectively support the inner wall of the blood vessel 300, preventing the retrieval hook 30 from adhering to the wall. Furthermore, during the implantation or retrieval of the filter 100, the deformation of the connection between the first support rod 2111 and the second support rod 2112 under external force can change the inclination of the first support rod 2111 and the second support rod 2112 relative to the central axis 1001 of the filter 100, and simultaneously change the overall radial dimension of the corrective component 20. When the distal opening of the sheath contacts the corrective component 20, the retrieval resistance can be reduced. Preferably, the included angle γ of a single support rod 211 is 30°, resulting in a smaller pushing force during implantation of the vena cava filter and facilitating removal.

[0089] In this embodiment, multiple support units 21 are symmetrically arranged about the central axis 1001 of the filter 100. Furthermore, the multiple support units 21 are respectively connected to the first tube 31 and the second tube 32, and the correction component 20 between the first tube 31 and the second tube 32 of the recovery hook 30 constructs a stable and flexible support structure. During the implantation phase of the filter 100, as the filter is advanced, the first support rod 2111 and the second support rod 2112 of the support unit 21, due to their inclined arrangement relative to the central axis 1001 and the angle between them, can be compressed and housed inside the sheath using their elastic deformation characteristics. During the distal movement and release relative to the sheath, the inclination of the support rod 211 changes with the resistance encountered, ensuring that the entire filter can be smoothly and successfully implanted at the designated location. After implantation, the multiple support units 21 elastically return from a compressed state to an unfolded state, allowing the support surfaces 201 of the multiple support units 21 to quickly and tightly adhere to the inner wall of the blood vessel, providing stable support for the filter and preventing displacement or tilting. During the retrieval phase, when the filter 100 needs to be retrieved, the sheath of the retrieval device approaches the filter 100, and the distal opening of the sheath contacts the corrective component 20. At this point, the connection between the first support rod 2111 and the second support rod 2112 begins to deform under the action of external force, changing the inclination of the first support rod 2111 and the second support rod 2112 relative to the central axis 1001. Simultaneously, it dynamically adjusts the overall radial dimension of the correction component 20, effectively reducing the recovery resistance. This allows the filter to be more smoothly drawn into the sheath, ultimately achieving a safe and convenient recovery operation.

[0090] Understandably, such as Figure 3c As shown, to facilitate the recycling of the filter 100, the number of support units 21 is between 6 and 10. Preferably, the number of support units 21 is 6, and the included angle β between any two adjacent support units 21 along the circumference of the filter 100 is 60°.

[0091] Furthermore, such as Figure 1a and Figure 1b As shown, the filter 11 includes a converging portion 111, a plurality of first filter branches 112, and a plurality of second filter branches 113. Both the first filter branches 112 and the second filter branches 113 have a rod-like structure. The distal ends of all the first filter branches 112 are connected to and converging at the converging portion 111. All the first filter branches 112 are arranged sequentially along the circumference of the filter 100, and the proximal ends of all the first filter branches 112 are arranged at intervals along the circumference of the filter 100. This ensures that any two adjacent first filter branches 112 are arranged at an angle along the circumference of the filter 100, and the angles between any two adjacent first filter branches 112 are equal.

[0092] Two adjacent first filter branches 112 along the circumference of filter 100 are provided with two corresponding second filter branches 113, and are connected to form a rhomboid mesh structure 210. Since two adjacent rhomboid mesh structures along the circumference of filter 100 share one first filter branch 112, the ratio of the number of second filter branches 113 to the number of first filter branches 112 in filter 11 is 2.

[0093] Further, please refer to Figure 1b As shown, a cross-section is made along the radial direction of the filter 100, perpendicular to the central axis 1001 of the filter 100. Along the extension direction of the central axis 1001, the support unit 21 of the correction component 20 has a first projection on the cross-section, and the first filter branch 112 has a second projection on the cross-section. There is a first projection between every two adjacent second projections, and the angle between the first and second projections is α1, and the angle between two adjacent second projections is α2, where α2 = 2 * α1. It should be noted that... Figure 1b It is the graphic structure of the filter from a view parallel to the central axis. Figure 1b The shape and structure of the support unit 21 and the first filter branch 112 shown are the same as the shape of the first projection and the second projection on the cross-section. Therefore, the first projection and the second projection are not shown here.

[0094] In an exemplary embodiment, the filter 11 includes six prismatic filters 11, that is, the filter 11 has six first filter branches 112 and twelve second filter branches 113. Among the six first filter branches 112, the included angle α2 between any two adjacent second projections along the circumference of the filter 100 is 60°, and the included angle α1 between the first projection and the second projection is 30°. This arrangement causes the support rod 211 to be offset from the first filter branches 112 of the filter 11 in the circumferential direction of the filter 100, thereby achieving dual filtration of thrombi. The corrective component 20 can intercept smaller thrombi, and the distal filter 11 can intercept larger thrombi.

[0095] In some embodiments, please combine Figure 2a , Figure 2b and Figure 3a , Figure 3bAs shown, all the support rods 211 enclose a support space 2101. Each support rod 211 has a first cutting edge 2102 extending along its length, with the first cutting edge 2102 facing inwards towards the support space 2101. The first cutting edge 2102 is a relatively sharp and narrow blade-like structure. Since the corrective component 20 replaces the retrieval hook 30 and abuts against the inner wall of the blood vessel when the filter 100 tilts, after a period of implantation in the blood vessel, endothelial overgrowth may occur on the corrective component 20, thus connecting part of the support rod 211 to the inner wall of the blood vessel. By providing the first cutting edge 2102 on the support rod 211, the first cutting edge 2102 can be used to cut the vascular endothelium during the retrieval process, thereby allowing the corrective component 20 to detach smoothly from the inner wall of the blood vessel, which helps to reduce retrieval resistance and smoothly retrieve the filter 100 into the sheath.

[0096] Understandably, all the support rods 211 of the corrective component 20 form a cage-like structure, and the internal space of the cage-like structure is the support space 2101. The surface of the support rods 211 facing away from the support space 2101 (that is, the circumferential outer surface of the corrective component 20) is used to contact the inner wall of the blood vessel. Therefore, by configuring the first cutting edge 2102 to face the inside of the support space 2101, it is possible to avoid the first cutting edge 2102 contacting the inner wall of the blood vessel and cutting the inner wall of the blood vessel. Furthermore, during the recovery process, as the corrective component 20 is compressed into the sheath, the cage-like structure formed by all the support rods 211 changes from an expanded state to a compressed state, causing the support rods 211 to move closer to the central axis 1001 of the filter 100, while the first blade 2102 is positioned towards the interior of the support space 2101, so that the direction of movement of the support rods 211 is similar to or consistent with the orientation of the first blade 2102. Thus, while recovering the corrective component 20, the action of the first blade 2102 cutting the endothelium can be satisfied.

[0097] In some embodiments, the support rod 211 is configured as a prism-shaped structure with sharp edges, such as an inverted cone or triangle cross-section, and the first cutting edge 2102 is the sharp edge structure on the support rod 211. In other embodiments, the first cutting edge 2102 is also configured as an elongated sharp blade-like structure formed on the outer surface of the support rod 211.

[0098] Furthermore, please combine Figure 1a and Figure 2aAs shown, the filter body 10 is also provided with multiple fixing anchors 14. Each support branch 12 has at least one fixing anchor 14 at its proximal end. The proximal end of the fixing anchor 14 is connected to the support branch 12, and the distal end of the fixing anchor 14 is suspended. From the proximal end to the distal end, the distal end of the fixing anchor 14 extends obliquely away from the central axis 1001 of the filter 100. By setting the fixing anchors 14, after the filter 100 is implanted into the human body, the fixing anchors 14 will pierce into the endothelium of the blood vessel 300, preventing the filter 100 from shifting under the action of blood flow. In this embodiment, the fixed anchor 14 and the support branch 12 are integrally cut and formed, and a receiving groove 15 corresponding to the fixed anchor 14 is also formed on the support branch 12. The contour of the receiving groove 15 matches the contour of the fixed anchor 14. During the recycling process of the filter 100 into the sheath, the fixed anchor 14 can be squeezed and stored in the receiving groove 15, thereby reducing the radial dimension of the filter 100 in the compressed state, which helps to reduce the recycling difficulty of the filter 100.

[0099] In this embodiment, the maximum diameter of the corrective component 20 is between 10mm and 25mm, and preferably, the diameter of the corrective component 20 is 10mm.

[0100] Example 2

[0101] The differences between Example 2 and Example 1 will be described below. The similarities or similarities between Example 2 and Example 1 will not be repeated here.

[0102] Specifically, please combine Figure 4a , Figure 4b , Figure 5a and Figure 5b As shown, the correction component 20 includes three support units 21, each support unit 21 including at least two support rods 211. Along the axial direction of the filter 100, at least two support rods 211 are connected in sequence, and any two adjacent support rods 211 are arranged at an angle.

[0103] Specifically, such as Figure 4a and Figure 5aAs shown, at least two support rods 211 include two first support rods 2111, two second support rods 2112, and one third support rod 2113. The first support rods 2111, the second support rods 2112, and the third support rod 2113 are all slender rod-shaped structures. One end of each first support rod 2111 is connected to the proximal end of the first tube 31, and the other end of each first support rod 2111 is connected to one end of a second support rod 2112. The other ends of the two second support rods 2112 are connected to one end of the third support rod 2113, and the other end of the third support rod 2113 is connected to the distal end of the second tube 32. A first plane is drawn along the radial direction of the filter 100. The first plane is perpendicular to the central axis 1001 of the filter 100. From the perspective of this plane, the projections of the two first support rods 2111, the two second support rods 2112, and the third support rod 2113 on the first plane present an arrangement in which any two are staggered. This layout allows the corrective component 20 to form a relatively dense mesh structure in the radial direction. This mesh structure is evenly distributed circumferentially and cooperates with the filter screen 11 of the filter body 10 in the axial direction, which can achieve the interception of thrombi of smaller size. The filter screen 11 at the distal end can perform secondary interception of larger thrombi.

[0104] In this embodiment, the dense mesh structure formed by the correction component 20 fills the gap in the ability of the filter body 10 and filter screen 11 to intercept thrombi, and can capture those small thrombus particles that may penetrate the filter screen 11, which greatly improves the interception efficiency of thrombi of different sizes and further reduces the risk of pulmonary embolism.

[0105] In detail, such as Figure 4b and Figure 5bAs shown, along the axial direction of the filter 100, the projection of the support unit 21 on the first plane is the first projection, and the projection of the first filter branch 112 on the first plane is the second projection. The first projection includes the first projection branch of the first support rod 2111, the second projection branch of the second support rod 2112, and the third projection branch of the third support rod 2113. The two first projection branches and two second projection branches in each support unit 21 are approximately "M" shaped, and the two second projection branches and one third projection branch are "Y" shaped. There is a first projection branch between each pair of adjacent second projections, and each third projection branch coincides with a second projection. The angle between the first projection branch and the second projection is α3, and the angle between two adjacent second projections is α4. Therefore, α4 = 2 * α3. In an exemplary embodiment, the filter 11 includes six prismatic filters 11, that is, the filter 11 has six first filter branches 112 and twelve second filter branches 113. Among the six first filter branches 112, the included angle α4 between any two adjacent second projections along the circumference of the filter 100 is 60°, and the included angle α3 between the first projection branch and the second projection is 30°. This arrangement causes the support rod 211 to be offset from the first filter branches 112 of the filter 11 in the circumferential direction of the filter 100, thereby achieving dual filtration of thrombi. The corrective component 20 can intercept smaller thrombi, and the distal filter 11 can intercept larger thrombi.

[0106] It should be noted that, Figure 4b It is the graphic structure of the filter from a view parallel to the central axis. Figure 4b The shape and structure of the support unit 21 and the first filter branch 112 shown are the same as the shape of the first projection and the second projection on the first plane. Therefore, the first projection and the second projection are not shown here.

[0107] Example 3

[0108] The differences between Example 3 and Example 1 will be described below. The similarities or similarities between Example 3 and Example 1 will not be repeated here.

[0109] In this embodiment, please refer to Figure 6a , Figure 6b , Figure 7a , Figure 7b , Figure 8 , Figure 9a , Figure 9b and Figure 9cAs shown, the filter 100 also includes a cutting component 40, which is connected to the recovery hook 30. The cutting component 40 includes multiple cutting elements 41, which are arranged sequentially around the central axis. Along the radial direction of the filter 100, the end of the cutting element 41 facing away from the central axis is closer to the central axis than the support surface 201. The cutting element 41 can cut free thrombi in blood vessels, thereby reducing the volume of a single thrombus. A second plane is formed along the radial direction of the filter 100, which is perpendicular to the central axis 1001 of the filter 100. The projections of the multiple support units 21 and the multiple cutting elements 41 on the second plane are alternately arranged along the circumference of the filter 100. That is, on the radial section of the filter, the support units 21 and the cutting elements 41 are staggered and evenly occupy space, which not only ensures support for the blood vessel wall but also achieves omnidirectional cutting of thrombi. Understandably, along the radial direction of the filter 100, the end of the cutter 41 facing away from the central axis is closer to the central axis than the support surface 201. The cutter 41 is in a relatively inward position. On the one hand, this prevents the cutter 41 from contacting the inner wall of the vein 300 and prevents the cutter 41 from cutting the inner wall of the vein 300. On the other hand, the cutter 41 can more efficiently intercept and cut free thrombi flowing from the deep veins of the lower limbs close to the blood vessel axis, so as to reduce the volume of a single thrombus and thus reduce the risk of thrombus blocking the vein 300.

[0110] Furthermore, in this embodiment, as Figure 7a and Figure 7b As shown, the projection of the support unit 21 onto the second plane is the first projection, the projection of the first filter branch 112 onto the second plane is the second projection, and the projection of the cutting piece 41 onto the second plane is the third projection. There is a third projection between every two adjacent first projections, and the angle between the first and third projections is θ. The angle between two adjacent first projections is α5, then α5 = 2*θ. In an exemplary embodiment, the correction component 20 includes six support units 21. If the angle α5 between any two adjacent support units 21 corresponding to the first projections is 60°, then the angle θ between the first and third projections is 30°.

[0111] It should be noted that, Figure 6b It is the graphic structure of the filter from a view parallel to the central axis. Figure 7b It is the graphic structure of the correction and cutting components from a view parallel to the central axis.

[0112] Figure 6b The supporting unit 21, the first filter branch 112, and the cutting element shown have the same shape as the first, second, and third projections on the second plane; therefore, the first, second, and third projections are not shown here. Similarly, Figure 7bThe shape and structure of the support unit 21 and the cutting element are the same as the shapes of the first and third projections on the second plane; therefore, the first and third projections are not shown here. Similarly, Figure 7b In

[0113] In one exemplary embodiment, see [link to example]. Figure 6a and Figure 6b As shown, the filter 11 includes six prismatic filters 11, that is, the filter 11 has six first filter branches 112 and twelve second filter branches 113. Among the six first filter branches 112, the included angle α6 between any two adjacent second projections along the circumference of the filter 100 is 60°, and the included angle D between the first projection and the third projection is 24°. This arrangement causes the first filter branches 112 to be offset from the cutter 41 in the circumferential direction of the filter 100, so that if a thrombus flows through the gap between the first filter branches 112, it will be cut into smaller thrombi by the cutter 41.

[0114] In some embodiments, see Figure 6a and Figure 6b As shown, along the radial direction of the filter 100, the diameter of the cutting component 40 is d1, and the diameter of the straightening component 20 is d2, where d2 = 2 * d1. In some exemplary embodiments, the diameter d1 of the cutting component 40 ranges from 5 mm to 13 mm, for example, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, etc. Preferably, the maximum diameter d1 of the cutting component 40 is 8 mm.

[0115] In this embodiment, as Figure 7a and Figure 9a As shown, the cutting element 41 includes at least two cutting rods connected sequentially along the axial direction of the filter 100, with any two adjacent cutting rods arranged at an angle. This arrangement allows the multiple cutting rods of the cutting element 41 to be compressed and housed inside the sheath during the insertion phase of the filter 100, thanks to their inclined arrangement relative to the central axis 1001 and the angled arrangement between any two cutting rods, utilizing their elastic deformation characteristics. During the process of moving and releasing the filter 100 distally relative to the sheath, the inclination of the cutting rods changes due to resistance, ensuring the entire filter can be smoothly and easily inserted into the designated position. During the recovery phase, when the filter 100 needs to be recovered, the sheath of the recovery device approaches the filter 100, with the distal opening of the sheath contacting the cutting element 40. At this time, the connection points of the multiple cutting rods begin to deform under external force, changing the diameter of the cutting element 40 and effectively reducing recovery resistance. This allows the filter to be more smoothly retracted into the sheath, ultimately achieving a safe and convenient recovery operation.

[0116] In some embodiments, such as Figure 9b and Figure 9c As shown, at least two cutting rods include a first cutting rod 411 and a second cutting rod 412. The included angle F between the first cutting rod 411 and the second cutting rod 412 ranges from 10° to 20°, for example, it can be 10°, 12°, 14°, 15°, 17°, 19°, 20°, etc. Preferably, the included angle F between the first cutting rod 411 and the second cutting rod 412 is set to 10°.

[0117] In this embodiment, as Figure 9b and Figure 9c As shown, all the cutting rods enclose a cutting space 401. Each cutting rod has a second blade 402 extending along its length. The second blade 402 is positioned facing outwards from the cutting space 401. The second blade 402 is a relatively sharp and narrow blade-like structure. By positioning the second blade 402 facing outwards from the cutting space 401, when the bolt flows through the cutting component 40, the bolt first contacts the second blade 402 and is then separated into smaller bolts by the second blade 402.

[0118] Understandably, all the cutting rods of the cutting component 40 form a cage-like structure, and the internal space of the cage-like structure is the cutting space 401. The surface of the cutting rod away from the support space 2101 (that is, the circumferential outer surface of the cutting component 40) can first contact the bolt. Therefore, by configuring the first cutting edge 2102 to face the outside of the cutting space 401, the second cutting edge 402 can better contact the bolt, thereby cutting the bolt.

[0119] In some embodiments, the cutting rod is configured as a prism-shaped structure with sharp edges, such as an externally conical or triangular cross-section, and the second cutting edge 402 is the sharp edge structure on the cutting rod. In other embodiments, the second cutting edge 402 is also configured as an elongated, sharp blade-like structure formed on the outer surface of the cutting rod.

[0120] Exemplarily, in some implementations, such as Figure 6a , Figure 7a and Figure 7b As shown, a cutting element 41 is provided between any two adjacent support units 21 along the circumference of the filter 100. The distal end of the first cutting rod 411 is connected to the proximal end of the first tube 31, the proximal end of the first cutting rod 411 is connected to the distal end of the second cutting rod 412, and the proximal end of the second cutting rod 412 is connected to the distal end of the second tube 32. This arrangement enhances the first-layer interception performance of the corrective component 20 against smaller thrombi, and the cutting element 40 fully utilizes the internal space of the corrective component 20, making the filter 100 more compact in the axial direction and reducing the overall volume of the filter 100.

[0121] In other embodiments, such as Figure 8 and Figure 9a As shown, along the axial direction of the filter 100, the cutting component 40 is located between the hook portion 301 and the straightening component 20. In this embodiment, the straightening component 20 and the cutting component 40 are spaced apart in the axial direction, so that as the thrombus flows with the blood, it is first cut into smaller thrombi by the cutting component 40 and then sequentially intercepted by the straightening component 20 and the filter screen 11.

[0122] Example 4

[0123] The differences between Example 4 and Example 1 will be described below. The similarities or similarities between Example 4 and Example 1 will not be repeated here.

[0124] In this embodiment, please refer to Figure 10a and Figure 10b As shown, the correction component 20 includes a connecting sleeve 22 and multiple support units 21. The connecting sleeve 22 is tubular and fixedly sleeved on the outside of the recovery hook 30. The multiple support units 21 are respectively connected to the connecting sleeve 22.

[0125] The support unit 21 includes multiple support rods 211, which are slender rods with good flexibility and strength, and can bend moderately under external force. The multiple support rods 211 are connected end to end to form a grid structure 210, and the multiple support units 21 are connected sequentially along the circumference of the filter 100, so that the corrective component 20 forms a mesh structure 23 with multiple grid structures 210. Specifically, the corrective component 20 is composed of eight rhomboid grids formed by eight support rods 211. The rhomboid grids are uniform in size and regularly arranged to form a structure that looks like a mesh. The gaps between the grids allow blood to pass through smoothly, while effectively intercepting thrombi of a certain size. Blood flows into the filter 100 from the deep veins of the lower limbs. Utilizing the flexibility of the support rods 211 and the gaps between the grids, larger thrombi with faster flow rates are intercepted in the first layer. Some thrombi are stuck by the rhomboid grids, preventing them from continuing to flow towards the heart and lungs. The blood that has been initially filtered by the corrective component 20 continues to flow to the filter body 10. At this time, the filter screen 11 of the filter body 10 captures the emboli that have leaked through the mesh gaps of the corrective component 20 again, achieving a second interception and ensuring that the blood entering the pulmonary artery is as pure as possible.

[0126] It should be noted that the corrective component 20 not only plays an interception role, but the mesh structure 23 of the corrective component 20 is evenly surrounded around the outer periphery of the retrieval hook 30. The support surface 201 on the outer side of the corrective component 20 fits tightly with the inner wall of the blood vessel, providing stable support, preventing the filter from tilting, and avoiding the retrieval hook 30 from contacting the inner wall of the blood vessel, which would cause the endothelium of the retrieval hook 30 to creep over.

[0127] The single-layer mesh tray tilt correction component 20 has 6 to 8 support units 21, each support unit 21 being a rhomboid mesh structure, meaning the correction component 20 includes 6 to 8 rhomboid meshes. Alternatively, a support unit 21 can be constructed by continuously bending a support rod 211 to create a rhomboid mesh structure. By setting an appropriate number of rhomboid meshes, excessive rod support can be avoided, preventing difficulties in retrieval, while simultaneously ensuring sufficient support performance and good thrombus interception performance.

[0128] Furthermore, the support rod 211 is configured as an arc-shaped rod, arching towards the proximal end from the proximal end to the distal end. The radius r1 of the arc of the support rod 211 ranges from 5mm to 10mm; for example, r1 can be set to 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc. Setting the support rod 211 as an arc-shaped rod facilitates smoother retraction of the straightening component 20 into the sheath during the retrieval process of the filter 100.

[0129] Furthermore, along the radial direction of the filter 100, a support portion 212 is provided at one end of the support rod 211 away from the central axis. The outer surface of the support portion 212 defines a support surface 201, and the outer surface of the support portion 212 is configured as an arc-shaped convex surface. In this embodiment, the support portion 212 is configured as a spherical structure. By using the arc-shaped outer surface of the support portion 212 to support the inner wall of the blood vessel, the probability of the corrective component 20 puncturing the inner wall of the blood vessel can be reduced.

[0130] Example 5

[0131] In this embodiment, please refer to Figure 11a and Figure 11b As shown, the recycling hook 30 includes a first tube 31 and a second tube 32. The proximal end of the filter body 10 (that is, the proximal end of all connecting rods 13) is connected to the distal end of the first tube 31, and the second tube 32 is provided with a hook 301.

[0132] The corrective component 20 includes a mesh structure 23 woven from braided filaments and a covering 24 adhered to the mesh structure 23. The circumferential outer surface of the mesh structure 23 defines a support surface 201. The support surface 201 formed by the circumferential outer surface of the corrective component 20 is smooth and flat, allowing it to perfectly conform to the inner wall of the blood vessel, ensuring the stable posture of the filter within the blood vessel. The distal end of the mesh structure 23 is connected to the proximal end of the first tube 31, and the proximal end of the mesh structure 23 is connected to the distal end of the second tube 32.

[0133] The straightening component 20 is arranged symmetrically up and down along the axial direction of the filter 100. The outer layer of the straightening component 20 is composed of interlaced woven mesh with 20 to 40 woven filaments. Preferably, the number of woven filaments is 26, which facilitates the recycling of the straightening component 20 and also provides better support. The material used for the woven filaments is a non-radioactive metal material, which can be one or more of nickel-titanium alloy, cobalt-chromium alloy, platinum-chromium alloy, and titanium. The inner layer of the straightening component 20 contains a membrane 24, which is closely attached to the interlaced woven mesh of the outer layer. The membrane 24 is made of a polymer material, which can be a PTFE membrane, PET membrane, etc.

[0134] In this embodiment, the mesh structure 23 of the corrective component 20, through the stable support of high-strength braided yarns, the tight connection with the retrieval hook 30, and the hemodynamic optimization of the membrane 24, ensures that the filter maintains a stable posture in complex blood flow environments. This effectively resists interference from factors such as blood flow impact and body movement, ensuring long-term reliable operation and reducing the probability of filter displacement, tilting, and other malfunctions. The use of the membrane 24 not only improves the blood compatibility of the corrective component 20 and reduces thrombus adhesion but also lowers the risk of inflammatory reactions. Furthermore, the filter can easily adapt to sheath operations during retrieval; the deformability of the braided yarns ensures smooth insertion into the sheath, reducing retrieval difficulty and trauma, and improving the convenience and efficiency of clinical operations.

[0135] Example 6

[0136] The difference between this embodiment and embodiments 1 to 5 is that, please refer to... Figure 1a and Figure 12 As shown, in this embodiment, the correction component 20, the filter screen 11, and the multiple support branches 12 are an integral structure, and the support rod 211 in the correction component 20 replaces the connecting rod 13 in embodiments 1 to 5.

[0137] In detail, such as Figure 12As shown, the filter body 10 includes a filter screen 11 and multiple support branches 12. The filter screen 11 is used to filter emboli in the blood and prevent them from entering the pulmonary artery with the blood. The filter screen 11 is formed by six diamond-shaped mesh structures 210 connected sequentially along the circumference of the filter 100 to form an umbrella-shaped structure with multiple meshes. The support branches 12 are rod-shaped structures. The proximal end of each diamond mesh structure is connected to the distal end of a support branch 12. The extension direction of the support branches 12 is parallel to the axial direction of the filter 100. The six support branches 12 are arranged sequentially at intervals along the circumference of the filter 100. The six support branches 12 are arranged in a ring around the central axis 1001 of the filter 100. After the filter 100 is implanted into the blood vessel 300, the support branches 12 are used to abut against the inner wall of the blood vessel 300 to keep the filter 100 stable inside the blood vessel 300, so as to ensure that the filter screen 11 can filter emboli in the blood for a long time.

[0138] The corrective component 20 includes multiple support rods 211, each having a first end 21101 and a second end 21102. The first end 21101 of each support rod 211 is connected to the proximal end of a support branch 12, and the second end 21102 of each support rod 211 is connected to the distal end of the retrieval hook 30. The second end 21102 is positioned further distally than the first end 21101. This arrangement causes the connection between the retrieval hook 30 and the support rod 211 to be recessed axially toward the interior of the filter body 10, thus centering the retrieval hook 30. This reduces the axial distance between the hook portion 301 of the retrieval hook 30 and the filter body 10, preventing the retrieval hook 30 from contacting the inner wall of the vein 300 when the filter 100 tilts within the vein 300.

[0139] To facilitate the retrieval of the vena cava filter while minimizing retrieval force, the angle Z between the support branch 12 and the support rod 211 is preferably set between 75° and 80°. Along the axial direction of the filter 100, the distance H1 between the proximal end of the retrieval hook 30 and the proximal end of the support branch 12 ranges from 3mm to 5mm. Furthermore, in this embodiment, the fixing anchor 14 is positioned at the connection between the filter screen 11 and the support branch 12. This avoids the fixing anchor 14 puncturing blood vessels, which would be a problem if it were positioned at the bend between the retrieval hook 30 and the support rod 211. It also ensures effective anchoring of the vena cava filter after implantation.

[0140] The implantation process of the filter 100 proposed in this embodiment is as follows:

[0141] like Figure 13 As shown, after the doctor completes the preoperative preparations and establishes the vascular access, the delivery device 200 is pushed to the designated position, and the filter 100 is pushed into the delivery device 200 through the delivery cable.

[0142] like Figure 14 As shown, because the filter 100 is made of a highly elastic material such as nickel-titanium alloy, its structure automatically expands and unfolds after it is pushed out from the head end of the delivery device 200. The support branch 12 on the filter 100 adheres to the blood vessel wall, and the anchor 14 is inserted into the vascular endothelium. Subsequently, the connection between the delivery device 200 and the filter 100 is released, and the delivery device 200 is withdrawn from the body.

[0143] like Figure 15 As shown, after the filter 100 is implanted in the human body for a period of time, the filter 100 tilts, and the corrective component 20 adheres to the blood vessel wall, thereby avoiding the situation where the filter 100 cannot be removed or is difficult to remove due to the retrieval hook 30 adhering to the blood vessel wall.

[0144] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A filter, characterized by, The filter includes a connected filter body, a corrective component, and a retrieval hook. The circumferential outer surface of the filter body is used to adhere to and support the inner wall of the blood vessel. The corrective component has a support surface for adhering to and supporting the inner wall of the blood vessel. The retrieval hook is provided with a hook portion for cooperating with a capture ring to retrieve the filter. Along the axial direction of the filter, the support surface is located between the filter body and the hook portion. Along the radial direction of the filter, the circumferential outer surface of the hook portion is closer to the central axis of the filter than the support surface.

2. The filter according to claim 1, characterized in that, The correction component includes multiple support units connected to the recovery hook and arranged sequentially around the central axis. Along the radial direction of the filter, the end face of the support unit opposite to the central axis defines the support surface, and the multiple support surfaces are arranged sequentially along the circumference of the filter.

3. The filter according to claim 2, characterized in that, The support unit includes at least two support rods arranged sequentially along the axial direction of the filter. The ends of the two support rods away from the central axis are connected to each other, and the two adjacent support rods are arranged at an angle to each other. The recycling hook includes a first tube and a second tube. The proximal end of the filter body is connected to the distal end of the first tube. The second tube is provided with the hook portion. The distal end of the support unit is connected to the proximal end of the first tube, and the proximal end of the support unit is connected to the distal end of the second tube.

4. The filter according to claim 3, characterized in that, The at least two support rods include a first support rod and a second support rod. One end of the first support rod is connected to the proximal end of the first tube, the other end of the first support rod is connected to one end of the second support rod, and the other end of the second support rod is connected to the distal end of the second tube. Alternatively, the at least two support rods may include two first support rods, two second support rods, and one third support rod. One end of each first support rod is connected to the proximal end of the first tube, and the other end of each first support rod is connected to one end of a second support rod. The other ends of the two second support rods are connected to one end of the third support rod, and the other end of the third support rod is connected to the distal end of the second tube. A first plane is drawn along the radial direction of the filter, and the projections of the two first support rods, the two second support rods, and the third support rod onto this first plane are staggered between any two of them.

5. The filter according to claim 3, characterized in that, All the support rods enclose a support space, and each support rod is provided with a first cutting edge extending along its own length direction, with the first cutting edge facing the interior of the support space.

6. The filter according to claim 2, characterized in that, The filter also includes a cutting component connected to the recycling hook. The cutting component includes multiple cutting elements arranged sequentially around the central axis. Along the radial direction of the filter, the end of each cutting element facing away from the central axis is closer to the central axis than the support surface. In this configuration, a second plane is formed along the radial direction of the filter, and the projections of the plurality of support units and the plurality of cutting elements on the second plane are alternately arranged along the circumference of the filter.

7. The filter according to claim 6, characterized in that, Along the axial direction of the filter, the cutting component is located between the hook and the straightening component; or, along the circumferential direction of the filter, a cutting component is provided between any two adjacent support units.

8. The filter according to claim 6, characterized in that, The cutting element includes at least two cutting rods connected sequentially along the axial direction of the filter, with any two adjacent cutting rods arranged at an included angle. All the cutting rods enclose a cutting space, and each cutting rod has a second cutting edge extending along its own length, with the second cutting edge facing outwards from the cutting space.

9. The filter according to claim 2, characterized in that, The corrective component also includes a connecting sleeve, which is sleeved over the retrieval hook, and the plurality of support units are respectively connected to the connecting sleeve; The support unit includes multiple support rods, which are connected to form a grid structure. The multiple support units are connected sequentially along the circumference of the filter, so that the correction component forms a mesh structure with multiple grid structures.

10. The filter according to claim 9, characterized in that, The support rod is configured as an arc-shaped rod, with the support rod arching towards the proximal end in the direction from the proximal end to the distal end; And / or, along the radial direction of the filter, the end of the support rod opposite to the central axis is provided with a support portion, the outer surface of the support portion defines the support surface, and the outer surface of the support portion is configured as an arc-shaped convex surface.

11. The filter according to claim 1, characterized in that, The corrective component includes a mesh structure woven from braided yarns, the circumferential outer surface of which defines the support surface; The recycling hook includes a first tube and a second tube. The proximal end of the filter body is connected to the distal end of the first tube. The second tube is provided with the hook portion. The distal end of the mesh structure is connected to the proximal end of the first tube, and the proximal end of the mesh structure is connected to the distal end of the second tube.

12. The filter according to any one of claims 1 to 11, characterized in that, The filter body, the correction component, and the recovery hook are arranged coaxially. Along the axial direction of the filter, the distance from the proximal end of the hook to the proximal end of the support surface is L1, and the distance from the proximal end of the hook to the proximal end of the circumferential outer surface of the filter body is L2. Along the radial direction of the filter, the distance from the support surface to the central axis is R1, and the radius of the filter body is R2, wherein L1 / R1 < L2 / R2.

13. The filter according to claim 1, characterized in that, The filter body includes a filter screen and multiple support branches. The support branches extend along the axial direction of the filter and are arranged sequentially along the circumferential direction of the filter, defining the circumferential outer surface of the filter body. The filter screen is connected to the distal end of each support branch. The corrective component includes a plurality of support rods, each support rod having a first end and a second end. The first end of each support rod is connected to the proximal end of a support branch, and the second end of each support rod is connected to the distal end of the retrieval hook. The second end is positioned closer to the distal end than the first end.

Images