A filter-combination inferior vena cava stent

Abstract

This invention discloses a filter-combined inferior vena cava stent, relating to the field of medical device technology. The stent includes a restraint end and an adjustment end connected to its two ends. A rotating structure for unblocking thrombi is connected between the restraint end and the adjustment end. The adjustment end also includes an adjustment structure for adjusting the mesh size of the adjustment end. This invention can aggregate and unblock thrombi, improving thrombolysis capacity, and can also personalize the mesh size of the filter according to the different blood vessel sizes of different patients.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a filter-combined inferior vena cava stent. Background Technology

[0002] Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is a leading preventable cause of death among hospitalized patients. 75%–90% of pulmonary emboli originate from thrombi in the deep veins of the lower extremities and the pelvic venous plexus. Therefore, preventing thrombi from the lower extremity veins from detaching and returning to the heart to cause pulmonary embolism is a crucial clinical task. While traditional anticoagulation therapy is effective, inferior vena cava filters have become a treatment option for preventing pulmonary embolism in patients with contraindications to anticoagulation, those who have failed anticoagulation therapy, or those with complications arising from anticoagulation, as well as in patients whose deep vein thrombosis has progressed despite adequate anticoagulation therapy.

[0003] Since their introduction in the 1970s, vena cava filters have undergone significant evolution, from permanent to recyclable, and from a single design to multiple types. However, traditional vena cava filters still have limitations, such as filter displacement, tilting, breakage, and difficulty in retrieval. These problems not only affect the effectiveness of the filter but may also pose additional risks and complications to patients.

[0004] Announcement No. (CN 117838373 A) discloses a filter-combined inferior vena cava stent. This invention's filter-combined inferior vena cava stent comprises a self-expanding stent and a filter. The self-expanding stent includes a narrow section and a wide section, both of which are woven wire mesh structures. The filter is a mesh structure with tapered ends and a cylindrical middle section. The filter is detachably connected to the mesh of the wide section of the self-expanding stent. This invention's filter-combined inferior vena cava stent utilizes a shape-memory alloy for both the stent and filter to simultaneously restore their shape, reducing the number of insertions after vascular placement. Because the narrow section of the stent proximal to the heart has a smaller inner diameter, it prevents the filter from shifting with blood flow. Since the filter does not directly contact the intima, with the contact area separated by a stent layer, the insertion time is significantly prolonged, thus providing better protection against thrombosis.

[0005] The proposed stent-type filter can effectively prevent filter displacement and tilting, while reducing the risk of filter-induced thrombosis. However, it cannot clear accumulated thrombi, nor can it personalize the mesh size of the filter according to the different blood vessel sizes of different patients. Summary of the Invention

[0006] To address the aforementioned problems, this invention aims to provide a filter-combined inferior vena cava stent that can aggregate and clear thrombi, enhance thrombolysis capabilities, and allow for personalized adjustment of the filter mesh size according to the different blood vessel sizes of different patients.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A filter-combination inferior vena cava stent includes a stent, with a restraint end and an adjustment end respectively connected to both ends of the stent;

[0009] A rotating structure for unblocking thrombi is provided between the constraint end and the adjustment end;

[0010] The adjustment end is also provided with an adjustment structure for adjusting the size of the mesh at the adjustment end.

[0011] Furthermore, the rotating structure includes a bidirectional rotating assembly connected to the constraint end and the adjustment end respectively, and a stirring assembly connected to the bidirectional rotating assembly.

[0012] Furthermore, the bidirectional rotating assembly includes a first helical torsion spring connected to the adjustment end and a second helical torsion spring connected to the constraint end, with a rotating shaft connecting the first and second helical torsion springs.

[0013] Furthermore, the first helical torsion spring rotates in the opposite direction to the second helical torsion spring.

[0014] Furthermore, the stirring assembly is a shape memory alloy component connected to a first helical torsion spring and a second helical torsion spring, respectively.

[0015] Furthermore, the adjustment structure includes a traction assembly connected to the end of the adjustment end, and an adjustment ring connected to the traction assembly, the adjustment ring being located at the bottom of the adjustment end.

[0016] Furthermore, the traction assembly includes a support rod connected to the end of the adjustment end, and a plurality of L-shaped connecting rods connected to the support rod, one end of each L-shaped connecting rod being connected to the inner wall of the adjustment ring.

[0017] Furthermore, the outer wall of the adjusting ring is movably connected to the bottom of the adjusting end.

[0018] Furthermore, the constraint end includes multiple connectors connected to the bracket, and multiple constraint lines respectively connected to the connectors and the second helical torsion spring.

[0019] The beneficial effects of this invention are: compared with the prior art, the improvement of this invention lies in that...

[0020] Through the coordinated action of the constraint end, rotating shaft, first and second helical torsion springs, and shape memory alloy strips, when the flow rate increases, the fluctuations generated by the change in flow rate compress the first and second helical torsion springs inside the stent. The first and second helical torsion springs are connected by the rotating shaft, and the rotation of the two helical torsion springs in opposite directions drives the double-cone bolt line to rotate. Helical torsion springs with opposite torsional directions are installed at both ends, rotating in opposite directions, while both shape memory alloy strips have a certain self-resetting ability. The agitation of the two shape memory alloy strips causes thrombi attached to the shape memory alloy strips to detach, and the rotation accelerates internal blood flow, clearing thrombi accumulated in the regulating end, thereby enhancing the thrombolytic ability.

[0021] Through the coordinated operation of structures such as the adjustment end, stent, limiting component, and top plate, the thrombus, after being cleared, can be further broken down through the mesh of the stent at the adjustment end. More preferably, medications such as urokinase and streptokinase can be applied to the stent at the adjustment end, causing the thrombus to be broken down into smaller fragments as it passes through the stent and enters the bloodstream. These fragments are further diluted and dissolved in the blood and may eventually be excreted through the kidneys in the urine. By clearing the thrombus through filtration to reduce its size, and then using medication to break down the filtered, smaller thrombus, the thrombus can be broken down more thoroughly, resulting in more efficient thrombus removal. Attached Figure Description

[0022] Figure 1 This is a front view of the overall structure of the filter-combined inferior vena cava stent of the present invention.

[0023] Figure 2 This is a three-dimensional schematic diagram of the overall structure of the filter-combined inferior vena cava stent of the present invention.

[0024] Figure 3 This is a bottom view of the filter of the present invention.

[0025] Figure 4 This is a schematic diagram of the filter of the present invention with part of the support removed.

[0026] Figure 5 This is a schematic diagram of the filter of the present invention without the support.

[0027] Figure 6 This is a schematic diagram of the filter of the present invention without the support and adjustment structure.

[0028] Figure 7 For the present invention Figure 6 Enlarged schematic diagram of part A.

[0029] Figure 8 This is a schematic diagram of the structure of the present invention with the support removed from another perspective.

[0030] Figure 9 For the present invention Figure 8 Enlarged view of part B in the image.

[0031] Figure 10 For the present invention Figure 8 Enlarged view of section C in the image.

[0032] The components are: 1. Constraint line, 2. Adjustment end, 3. Bracket, 4. Connector, 5. Placement platform, 6. No. 1 helical torsion spring, 7. Connecting sleeve, 8. Rotating shaft, 9. Memory alloy strip, 10. Adjustment ring, 11. Buckle, 12. Protective sleeve, 13. Baffle, 14. No. 2 helical torsion spring, 15. Fixing ring, 16. Connecting ring, 17. Limiting component, 18. Top plate, 19. End, 20. Support rod, 21. Fixing rod, 22. L-shaped connecting rod. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0035] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0036] In the description of this application, it should be noted that the terms "center," "upper," "lower," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0037] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0038] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms “set up,” “install,” “connect,” and “link” should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components.

[0039] Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0040] Please see Figures 1-10 This application discloses a filter-combined inferior vena cava stent, including a stent 3, with a constraint end and an adjustment end 2 respectively connected to both ends of the stent 3; a rotating structure for clearing thrombi is connected between the constraint end and the adjustment end 2; the adjustment end 2 is also provided with an adjustment structure for adjusting the mesh size of the adjustment end 2.

[0041] It should be noted that the stent 3 in this application is a self-expanding stent. Self-expanding stents have good elasticity and support, and can be used for different patients' blood vessel shapes and sizes. Specifically, utilizing the pressure brought by blood flow, when the blood contains thrombi, the blood flow is slower. When the thrombus enters the device, it first laterally compresses the external arc-shaped skeleton of the self-expanding stent under pressure. The arc-shaped skeleton expands outward, and when deformed, the device fits tightly against the inner wall of the blood vessel. Furthermore, the self-expanding stent of this application includes a restraining end and an adjusting end 2. The stent at the restraining end has a larger diameter to provide sufficient support area; the stent at the adjusting end 2 has a thinner structure and is used at the proximal end.

[0042] Self-expanding stents are preferably made of metal wire, such as a mesh-like structure woven from nickel-titanium alloy. This material has good elasticity and biocompatibility, and can adapt to changes in the shape of blood vessels and reduce vascular damage.

[0043] It should be noted that the blood flow rate in the inferior vena cava is slow under normal circumstances, but the blood flow rate in the inferior vena cava can change due to external factors.

[0044] For example, when sneezing: Sneezing is a sudden, forceful respiratory action that causes a rapid, instantaneous increase in pressure within the chest cavity. This pressure change is transmitted through blood vessels to the inferior vena cava, causing a corresponding increase in pressure within the inferior vena cava. Due to the increased pressure in the inferior vena cava, the resistance to blood return to the heart increases, and under the influence of this pressure difference, the blood flow velocity within the inferior vena cava slows down significantly for a short period. Once the sneezing action ends, the pressure within the chest cavity gradually returns to normal, and the pressure within the inferior vena cava also decreases, with the blood flow velocity gradually returning to normal levels.

[0045] Aerobic exercise: During aerobic exercise, the body's metabolic needs increase, the sympathetic nervous system is stimulated, prompting the heart to beat faster and the myocardial contractility to increase. This results in a larger stroke volume, with more blood being pumped into the aorta and then flowing through the arterial system to all tissues and organs throughout the body. Due to the continuity of blood circulation, the amount of blood returning from the tissues and organs to the heart also increases accordingly, and the inferior vena cava, as an important return channel, naturally experiences a faster blood flow.

[0046] Therefore, under normal conditions, the blood flow rate in the inferior vena cava is slow, and the ability of the anterior segment to dissolve thrombi is limited. However, this application designs the regulating end 2 as a conical structure, which creates a flow velocity difference between the central part and the periphery during the flow process. Thrombi in the blood will aggregate towards the center to a certain extent, which will further slow down the blood flow rate in the central part, thereby slowing down the thrombus dissolution rate. External force is required to break this aggregation phenomenon and reduce the impact of the flow velocity difference.

[0047] Based on the above description, this application provides a rotating structure, which includes a bidirectional rotating component connected to the constraint end and the adjustment end 2 respectively, and a stirring component connected to the bidirectional rotating component.

[0048] The bidirectional rotating assembly includes a first helical torsion spring 6 connected to the adjustment end 2 and a second helical torsion spring 14 connected to the constraint end. A rotating shaft 8 is provided between the first helical torsion spring 6 and the second helical torsion spring 14.

[0049] The rotation direction of the first helical torsion spring 6 is opposite to that of the second helical torsion spring 14.

[0050] The constraint end of this application includes multiple connectors 4 connected to the bracket 3, and multiple constraint lines 1 connected to the connectors 4 and the second helical torsion spring 14 respectively. The constraint lines 1 are preferably made of elastic rubber and are used to connect the second helical torsion spring 14 and the connectors 4.

[0051] The stirring assembly includes shape memory alloy components connected to the first helical torsion spring 6 and the second helical torsion spring 14, respectively. Specifically, the shape memory alloy components are two shape memory alloy strips 9, which are irregularly shaped and arranged inside the self-expanding support to facilitate the expansion of the stirring area. One end of each shape memory alloy strip 9 is fixedly connected to the placement platform 5 above the first helical torsion spring 6, and the other end is fixedly connected to the connecting platform below the second helical torsion spring 14.

[0052] Specifically, aerobic exercise is used to increase blood flow rate. When the flow rate increases, the fluctuations generated by the change in flow rate compress the first helical torsion spring 6 and the second helical torsion spring 14 inside the device. The first helical torsion spring 6 and the second helical torsion spring 14 are connected by a rotating shaft 8. The rotation of the two helical torsion springs in opposite directions drives the double-cone bolt line to rotate. Helical torsion springs with opposite torsional directions are installed at both ends, rotating in opposite directions. Both shape memory alloy strips 9 have a certain self-resetting ability. The agitation of the two shape memory alloy strips 9 causes the thrombus attached to the shape memory alloy strips 9 to detach. At the same time, the rotation accelerates the internal blood flow, clearing the thrombus accumulated in the regulating end 2, thereby achieving the purpose of improving the thrombolysis ability.

[0053] More specifically, when blood flow increases, the two helical torsion springs are subjected to pressure. Both helical torsion spring 6 (number one) and helical torsion spring 14 (number two) are conical horizontal helical torsion springs, and these springs rotate under pressure. This is because the design principle of the conical horizontal helical torsion spring is to store elastic energy through torsion. When the conical horizontal helical torsion spring is under pressure, its outer circumference changes, and this deformation causes it to rotate around its own axis. Conical horizontal helical torsion springs are widely used in various mechanical devices, mainly for bearing and controlling rotational and torsional forces and energy.

[0054] The working principle of a conical horizontal helical torsion spring is to store elastic potential energy through torsional deformation. When an external force is applied to the conical horizontal helical torsion spring, causing it to compress, the spring stores this energy. When the external force disappears, the spring releases the stored elastic energy, generating torque or rotational force to return it to its original state. During this process, rotation of the conical horizontal helical torsion spring is unavoidable.

[0055] Furthermore, the characteristics of conical horizontal helical torsion springs also give them unique rotational behavior under pressure. Because the diameter of the spring coils in a conical horizontal helical torsion spring gradually changes from one end to the other, the magnitude of the force and the degree of deformation of each coil will differ under pressure. This difference causes the spring to rotate during compression, further increasing its complexity and functionality.

[0056] Therefore, the first helical torsion spring 6 and the second helical torsion spring 14 of this application will rotate when subjected to pressure, which is determined by their design principle and working characteristics.

[0057] It should be noted that the fixed ring 15 and the connecting ring 16 are fixedly connected by the fixed rod 21. When the second helical torsion spring 14 rotates axially, the fixed ring 15 can prevent the second helical torsion spring 14 from moving in the up and down direction, so that the second helical torsion spring 14 can only rotate axially, thus ensuring the direction of rotation of the second helical torsion spring 14.

[0058] Because each patient's condition is different, the acceptable size of the filtered thrombus varies. Therefore, this application also includes an adjustment structure for adjusting the mesh size of the stent at the adjustment end 2. This allows large thrombi after filtration to be further broken down through the mesh of the stent at the adjustment end 2. More preferably, medications such as urokinase or streptokinase can be applied to the stent at the adjustment end 2, causing the thrombus to be broken down into smaller fragments as it passes through the stent and enter the bloodstream. These fragments are further diluted and dissolved in the blood and may eventually be excreted through the kidneys in the urine. By using a rotating structure to clear the thrombus and then using medication to break it down, the thrombus can be broken down more thoroughly, resulting in more efficient thrombus removal.

[0059] The adjustment structure includes a traction assembly connected to the end of the adjustment end 2, and an adjustment ring 10 connected to the traction assembly, the adjustment ring 10 being located at the bottom of the adjustment end 2.

[0060] The traction assembly includes a support rod 20 connected to the end of the adjustment end 2, and multiple L-shaped connecting rods 22 connected to the support rod 20. One end of each L-shaped connecting rod 22 passes through the connecting ring 16 and is connected to the inner wall of the adjustment ring 10. The other ends are gathered in the limiting member 17 and connected to the top plate 18. The top plate 18 is fixedly connected to the end 19 of the adjustment end 2 via the support rod 20. A protective sleeve 12 is fitted onto one lateral end of each L-shaped connecting rod 22. A retrieval hook is also provided at the upper end of the end 19. If the stent 3 is not to be left in the blood vessel, it can be retrieved using the retrieval hook on the end 19.

[0061] Specifically, the supports of the adjusting end 2 are all gathered together to form an opening. The opening has internal threads, and the end 19 of the adjusting end is fitted into the opening and threadedly connected to it. The limiting member 17 is a spring, and the other end of each L-shaped connecting rod 22 is fitted inside the spring. Furthermore, the other ends of each L-shaped connecting rod 22 are gathered together and connected to the top plate. The doctor can adjust the density of the adjusting end according to the patient's condition. When the mesh size of the support 3 of the adjustment end 2 needs to be reduced, the end of the adjustment end is rotated downwards, causing the connecting support rod 20 connected to it to move downwards, which in turn causes the top plate 18 to move downwards. The top plate 18 then causes multiple L-shaped connecting rods 22 connected to it to move downwards. Finally, the multiple L-shaped connecting rods 22 cause the adjusting ring 10 connected to it to move downwards. When the adjusting ring 10 moves downwards, the distance between the supports 3 of the adjustment end 2 decreases, thus reducing the mesh size of the support 3 of the adjustment end 2. Conversely, when the doctor needs to increase the mesh size of the support 3 of the adjustment end 2, the end 19 of the adjustment end 2 is rotated upwards, which will cause the adjusting ring 10 to move upwards, thus enlarging the mesh size of the support 3 of the adjustment end 2. Further details are omitted here.

[0062] The outer wall of the adjusting ring 10 is snapped into the bottom of the adjusting end 2. Specifically, the outer wall of the adjusting ring 10 is snapped into the bottom of the bracket 3 of the adjusting end 2 by a buckle 11, which is fixedly located on the outside of the adjusting ring 10. Figure 6 As shown, the adjusting ring 10 is equipped with buckles 11 corresponding to the number of brackets. Each buckle 11 is locked onto the bracket 3, and the buckles 11 can drive the adjusting ring 10 to move up and down on the bracket 3. By moving the adjusting ring 10 up and down on the bracket 3, the mesh of the bracket 3 can be expanded or stretched to reduce its size, thereby achieving the effect of adjusting the mesh of the bracket 3.

[0063] Example 1

[0064] When using the filter-combination inferior vena cava stent of this application to treat deep vein thrombosis, the patient was placed in a supine position under ECG monitoring. After routine disinfection and draping, the right femoral vein was chosen as the puncture site. Local anesthesia was administered using 5ml of 2% lidocaine hydrochloride. The femoral vein was punctured, and a 5F sheath was placed. A guidewire and a pigtail catheter were then inserted into the inferior vena cava. Angiography showed significant stenosis of the inferior vena cava with irregular vessel walls. Simultaneously, biochemical tests indicated a hypercoagulable state. The guidewire was probed through the narrowed segment and inserted into the right atrium. A balloon was then introduced from the stenotic site of the inferior vena cava to dilate the narrowed segment. The blood flow in the inferior vena cava improved compared to before. The filter-combination inferior vena cava stent of this application was then inserted and released after being positioned at the obstructed segment of the inferior vena cava. Angiography showed that the inferior vena cava lumen was patent, the stent and filter dilated well, blood flow velocity significantly increased, and collateral circulation opening decreased. The treatment was satisfactory. The catheter sheath was withdrawn, and the puncture site was pressure-bandaged. The patient was safely returned to the ward after the procedure.

[0065] Twenty days later, the patient was placed in a supine position under ECG monitoring. The right femoral vein was chosen as the puncture site. Routine disinfection and draping were performed, and the puncture site was anesthetized with 5 ml of 2% lidocaine. After successful femoral vein puncture, a 6F sheath and a 4F pigtail cannula were introduced for inferior vena cava angiography. The inferior vena cava stent site showed good visualization, as did both renal veins. Filling defects were observed within the filter. When the filter-combination inferior vena cava stent is placed in the blood vessel, the flowing blood passing through stent 3 causes thrombi to accumulate within it. The continuous flow of blood exerts pressure on the accumulated thrombi. Sneezing or aerobic exercise increases blood flow velocity. This increased velocity creates fluctuations that compress the first and second helical torsion springs 6 and 14 inside stent 3. These springs are connected by a pivot, and the rotation of the two opposing helical torsion springs drives the rotation of the double-cone bolt wire. Two helical torsion springs with opposite twisting directions are installed at both ends, rotating in opposite directions respectively, while both shape memory alloy strips 9 have a certain self-resetting ability. The agitation of the two shape memory alloy strips 9 causes the thrombus attached to them to fall off, and the rotation accelerates the internal blood flow, clearing the thrombus accumulated in the regulating end 2, thereby achieving the purpose of improving the thrombolysis ability.

[0066] A second angiography showed that the inferior vena cava had unobstructed blood flow, but local filling defects were still observed. Some collateral branches were opened, and the femoral vein pin was removed and bandaged. The patient had no complaints of discomfort during the operation and returned to the ward safely after the operation.

[0067] Example 2

[0068] The usage method and process of this embodiment are the same as those of Embodiment 1. The only difference is that, before the filter-combination inferior vena cava stent of this embodiment is inserted into the patient's inferior vena cava, the mesh size of the adjusting end 2 needs to be adjusted according to the patient's condition. When it is necessary to reduce the mesh size of the stent at the adjusting end 2, the end 19 of the adjusting end 2 is rotated downward, causing the end 19 of the adjusting end 2 to move the support rod 20 connected to it downward, which in turn moves the top plate 18 downward. The top plate 18 will then move the multiple L-shaped connecting rods 22 connected to it downward, and finally the multiple L-shaped connecting rods 22 will move the adjusting ring 10 connected to it downward. When the adjusting ring 10 moves downward, the distance between the stents 3 at the adjusting end 2 decreases, thereby reducing the mesh size of the stent 3 at the adjusting end 2. Conversely, when the doctor needs to increase the mesh size of the stent 3 at the adjusting end 2, the end 19 of the adjusting end 2 is rotated upward, which will eventually move the adjusting ring 10 upward, expanding the mesh size of the stent 3 at the adjusting end 2.

[0069] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A filter-combination inferior vena cava stent, comprising a stent (3), characterized in that: The bracket (3) is respectively connected to a constraint end and an adjustment end (2) at both ends; A rotating structure for unblocking thrombi is provided between the constraint end and the adjustment end; The adjustment end (2) is also provided with an adjustment structure for adjusting the mesh size of the adjustment end (2).

2. The filter-combination inferior vena cava stent according to claim 1, characterized in that: The rotating structure includes a bidirectional rotating assembly connected to the constraint end and the adjustment end (2) respectively, and a stirring assembly connected to the bidirectional rotating assembly.

3. The filter-combination inferior vena cava stent according to claim 2, characterized in that: The bidirectional rotating assembly includes a first helical torsion spring (6) connected to the adjustment end (2) and a second helical torsion spring (14) connected to the constraint end. A rotating shaft (8) is provided between the first helical torsion spring (6) and the second helical torsion spring (14).

4. The filter-combination inferior vena cava stent according to claim 3, characterized in that: The first helical torsion spring (6) rotates in the opposite direction to the second helical torsion spring (14).

5. The filter-combination inferior vena cava stent according to claim 4, characterized in that: The stirring assembly is a shape memory alloy component that is connected to the first spiral torsion spring (6) and the second spiral torsion spring (14) respectively.

6. The filter-combination inferior vena cava stent according to claim 5, characterized in that: The adjustment structure includes a traction assembly connected to the end of the adjustment end (2) and an adjustment ring (10) connected to the traction assembly, the adjustment ring (10) being located at the bottom of the adjustment end (2).

7. The filter-combination inferior vena cava stent according to claim 6, characterized in that: The traction assembly includes a support rod (20) connected to the end of the adjustment end (2), and a plurality of L-shaped connecting rods (22) connected to the support rod (20), one end of each L-shaped connecting rod (22) being connected to the inner wall of the adjustment ring (10).

8. The filter-combination inferior vena cava stent according to claim 7, characterized in that: The outer wall of the adjusting ring (10) is movably connected to the bottom of the adjusting end (2).

9. The filter-combination inferior vena cava stent according to claim 8, characterized in that: The constraint end includes multiple connectors (4) connected to the bracket (3), and multiple constraint lines (1) connected to the connectors (4) and the second helical torsion spring (14) respectively.

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