Transfemoral vein filter recovery device

Abstract

The utility model relates to a transfemoral vein filter recovery device which comprises a recovery sheath tube and a capturing device, a recovery window is formed in the tube wall of the recovery sheath tube, the recovery sheath tube is provided with a developing part, and the developing part is located at the far end of the position, where the recovery window is arranged, of the recovery sheath tube; the capturing device can move in the axial direction of the recycling sheath tube and is used for capturing a recycling hook of the filter and pulling the filter into the recycling sheath tube towards the far end through the recycling window relative to the recycling sheath tube. According to the transfemoral vein filter recovery device, the capture device is used for moving the filter towards the far end relative to the recovery sheath tube through the recovery window so as to enter the recovery sheath tube to recover the filter, and due to the fact that the whole operation process can enter from the vein, the operation risk of filter recovery is reduced, and long-term complications are reduced.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a device for recovering filters via the femoral vein. Background Technology

[0002] Venous thromboembolism (VTE) is a common clinical condition with high morbidity and mortality. VTE includes deep vein thrombosis (DVT) and pulmonary embolism (PE). DVT commonly occurs in the veins of the lower extremities, while PE is mainly caused by thrombi forming in the venous system or right heart and then detaching into the pulmonary artery, making it a major cause of disease and death. Anticoagulation therapy has always been the gold standard for VTE treatment, aiming to prevent thrombus formation, prevent PE, and restore the patency of the embolized vein. When patients have contraindications to anticoagulation or experience bleeding complications that necessitate discontinuation of anticoagulation, implantation of a vena cava filter (VCF) can effectively intercept detached thrombi and prevent fatal pulmonary embolism. Early vena cava filters were primarily permanent filters; a disadvantage of these filters is their potential to cause long-term complications such as inferior vena cava obstruction.

[0003] In recent years, retrievable filters have gradually become the mainstream. After the risk of pulmonary embolism (PE) has been eliminated, the filter can be retrieved, thus avoiding complications caused by long-term filter implantation. Compared with permanent inferior vena cava filters, retrievable filters have better thrombus capture, a lower probability of sequelae, and are more affordable. Their advantages complement the disadvantages of permanent inferior vena cava filters.

[0004] Recyclable filters mainly include fusiform filters and umbrella filters. Compared to columnar filters, fusiform and umbrella filters avoid large-area contact with the blood vessel wall, thus providing a longer recovery time window and causing less damage to the blood vessel wall during recovery. In recent years, structural improvements to fusiform and umbrella filters have also resulted in excellent centering performance. Therefore, fusiform and umbrella filters are gradually becoming the development trend of filters.

[0005] However, in related technologies, retrievable filters can only be retrieved via the jugular vein. Retrieving umbrella-shaped filters via the jugular vein carries high surgical risks and is prone to long-term complications. For example, puncturing the jugular vein can easily injure the carotid artery or enter the vertebral artery or pleural cavity; moreover, even if the puncture is successful, how to bypass the heart with the guidewire and catheter remains a challenge, and a large sheath entering the heart can induce arrhythmias; umbrella-shaped filters are prone to tilting, and their anchor hooks can easily penetrate the vessel wall.

[0006] Therefore, it is urgent to address the issue of high risks and long-term complications associated with filter recycling procedures. Utility Model Content

[0007] Based on this, this technology proposes a femoral vein filter retrieval device to address the problem of how to reduce the surgical risks of filter retrieval and decrease long-term complications.

[0008] This application provides a femoral vein filter retrieval device, which is used to retrieve a filter with a retrieval hook at its distal end. The femoral vein filter retrieval device includes:

[0009] A recovery sheath, wherein the wall of the recovery sheath is provided with a recovery window, and the recovery sheath is provided with a developing section, which is located at the distal end of the recovery sheath where the recovery window is located;

[0010] A catcher, which is axially movable along the recovery sheath, is used to catch the retrieval hook of the filter and pull the filter distally into the recovery sheath via the retrieval window relative to the recovery sheath.

[0011] In one embodiment, the recovery sheath forms a bend at the corresponding recovery window, the bend bends toward the side where the recovery window is located, and the included angle between the sections of the recovery sheath at both ends of the bend is 150°~160°.

[0012] In one embodiment, the catcher includes a catch ring, a guide wire, a catch conduit, and a torque adjustment assembly. The catch ring is connected to the distal end of the guide wire, the guide wire passes through the catch conduit, and the torque adjustment assembly is located at the proximal end of the catch conduit and connected to the proximal end of the guide wire. The torque adjustment assembly is used to pull the guide wire to move axially relative to the catch conduit.

[0013] In one embodiment, the capture conduit is made of nickel-titanium alloy or stainless steel.

[0014] In one embodiment, the transfemoral vein filter retrieval device includes a dilator with a distal tapered end, the dilator being able to pass through the retrieval sheath from the proximal end of the retrieval sheath, and the dilator being movable axially relative to the retrieval sheath.

[0015] In one embodiment, the developing section includes a developing ring, which is sleeved on the outside of the recovery sheath or embedded in the inner wall of the recovery sheath.

[0016] In one embodiment, the imaging ring covers 1 / 3 to 1 / 2 of the circumference of the recovery sheath.

[0017] In one embodiment, the length of the recovery window along the axial direction of the recovery sheath is 10mm to 30mm, and the depth of the recovery window in the radial direction of the recovery sheath is 0.55mm to 2.5mm.

[0018] In one embodiment, the distance from the developing section to the distal end of the recovery sheath is 60mm to 70mm.

[0019] In one embodiment, the inner diameter of the recovery sheath is 3mm to 4mm, and the outer diameter is 4mm to 6mm.

[0020] In one embodiment, the recycled sheath is made of polypropylene, polyamide, high-density polyethylene, or polyetheretherketone.

[0021] The aforementioned femoral vein filter retrieval device features a retrieval window in the wall of the retrieval sheath and a contrast-enhancing section located distal to the retrieval window. This contrast-enhancing section allows for precise movement of the retrieval sheath to a suitable position, aligning the retrieval window with the filter's retrieval hook. By manipulating a catcher along the retrieval sheath to capture the hook, and then manipulating the catcher relative to the retrieval sheath axially, the filter moves distally through the retrieval window into the sheath. The filter is then retrieved by withdrawing it from the body along with the retrieval sheath and catcher. Because this femoral vein filter retrieval device allows for intravenous access throughout the procedure, it avoids the high surgical risks and long-term complications associated with retrieval of umbrella-shaped filters via the jugular vein approach in related technologies. Therefore, the femoral vein filter retrieval device of this application reduces the surgical risks of filter retrieval and minimizes long-term complications. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other embodiments can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a partial structural schematic diagram of a femoral vein filter recovery device according to one embodiment.

[0024] Figure 2 This is a schematic diagram of the capture device in a femoral vein filter recovery device according to one embodiment.

[0025] Figure 3This is a partial structural schematic diagram of a femoral vein filter recovery device according to another embodiment.

[0026] Figure 4 This is a schematic diagram of the structure of a femoral vein filter retrieval device in one embodiment, where the retrieval sheath enters the blood vessel and the retrieval window is near the retrieval hook of the umbrella-shaped filter.

[0027] Figure 5 This is a schematic diagram showing the structure of the capture ring of the capture device capturing the retrieval hook of the umbrella-shaped filter during use of the femoral vein filter retrieval device according to one embodiment.

[0028] Figure 6 This is a schematic diagram of the structure of a femoral vein filter retrieval device in one embodiment, showing the catcher moving the retrieval hook of the umbrella-shaped filter to the far end of the retrieval window during use.

[0029] Figure 7 This is a schematic diagram of the structure of a femoral vein filter retrieval device in one embodiment, showing the capture device completely moving the umbrella-shaped filter into the retrieval sheath at the distal end of the retrieval window.

[0030] Figure label:

[0031] 10. Retrieval sheath; 11. Retrieval window; 12. Imaging section; 12a. Imaging ring; 13. Bending section; 20. Catch device; 21. Catch ring; 22. Conductive wire; 23. Catch catheter; 24. Torque adjustment assembly; 30. Umbrella filter; 31. Filter body; 32. Retrieval hook; 33. Anchor hook; VW, vessel wall. Detailed Implementation

[0032] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0033] It should be noted that when a component is described as "fixed to" or "set on" another component, it can be directly on the other component or there may be an intervening component. When a component is described as "connected to" another component, it can be directly connected to the other component or there may be an intervening component.

[0034] The terms “vertical,” “horizontal,” “up,” “down,” “left,” “right,” and similar expressions are for illustrative purposes only and do not represent the only possible implementation.

[0035] It should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. 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.

[0036] It should be noted that the terms "distal" and "proximal" are used as directional terms in the field of interventional medical devices. "Distal" refers to the end furthest from the operator (e.g., the doctor) during surgery, or the end relatively far from the patient's heart during surgery (i.e., the distal end). "Proximal" refers to the end closest to the operator during surgery, or the end closest to the patient's heart during surgery (i.e., the proximal end). Axial direction refers to the direction in which the central axis of the medical device extends; radial direction refers to the direction perpendicular to the aforementioned axial direction.

[0037] See Figure 1 and Figure 2 As shown in the figure, this application embodiment provides a femoral vein filter retrieval device, including a retrieval sheath 10 and a catcher 20. The retrieval sheath 10 has a retrieval window 11 in its wall and a imaging section 12. The imaging section 12 serves as a structural component for marking the location of the retrieval sheath 10 within the body, facilitating monitoring of the filter's position during operation. The imaging section 12 is located distal to the location of the retrieval window 11 on the retrieval sheath 10.

[0038] The catcher 20 is capable of moving along the axial direction of the recovery sheath 10. The catcher 20 is used to catch the recovery hook 32 of the filter and pull the filter into the recovery sheath 10 at a distal end relative to the recovery window 11.

[0039] To facilitate understanding of the recovery effect of the femoral vein umbrella filter 30 recovery device on the umbrella filter 30, the following description will focus on the structure of the umbrella filter 30.

[0040] Combination Figures 4 to 7 As shown, the umbrella-shaped filter 30 includes a filter body 31, a retrieval hook 32, and an anchor hook 33. The retrieval hook 32 is located at the proximal end of the filter body 31 and is used to cooperate with the retrieval device when the umbrella-shaped filter 30 is retrieved, so that the retrieval device can capture the umbrella-shaped filter 30. The anchor hook 33 is located at the distal end of the filter body 31 and is used to anchor in the blood vessel wall VW to fix the filter body 31.

[0041] The inventors discovered that because the retrieval hook 32 of the umbrella filter 30 is located at the proximal end (i.e., the end closer to the patient's heart), and the anchor hook 33 is located at the distal end (i.e., the end farther from the patient's heart) and anchored in the vessel wall VW, when retrieving the umbrella filter 30 via the transjugular retrieval method in related technologies, the carotid artery is easily injured or the vertebral artery or pleural cavity may enter during jugular puncture; moreover, even if the puncture is successful, the guidewire and catheter are difficult to bypass the heart, and the entry of a large sheath into the heart can induce arrhythmias; the umbrella filter 30 is prone to tilting, and its anchor hook 33 is prone to penetrating the vessel wall VW. Therefore, when retrieving the umbrella filter 30 using the umbrella filter 30 retrieval device in related technologies, it is difficult to meet the needs of low surgical risk and reduced long-term complications.

[0042] In this embodiment, the femoral vein umbrella filter 30 retrieval device provided in this application has a retrieval window 11 on the wall of the retrieval sheath 10. The retrieval sheath 10 is provided with a imaging section 12, which is located distal to the location of the retrieval window 11. This imaging section 12 allows the retrieval sheath 10 to be accurately moved to a suitable position, so that the retrieval window 11 corresponds to the retrieval hook 32 of the umbrella filter 30. Thus, by operating the catcher 20 to move along the retrieval sheath 10 to the position to catch the retrieval hook 32, and after catching the retrieval hook 32, the catcher 20 can be operated to move axially relative to the retrieval sheath 10, causing the umbrella filter 30 to move distally relative to the retrieval sheath 10 through the retrieval window 11 and enter the retrieval sheath 10. In this way, the umbrella filter 30 can be retrieved by withdrawing it from the body along with the retrieval sheath 10 and the catcher 20. Because the entire operation of the femoral vein umbrella filter 30 retrieval device of this structure can be performed via a venous approach, it avoids the high surgical risk and long-term complications associated with the use of the jugular vein for retrieval of the umbrella filter 30 in related technologies. Therefore, the femoral vein umbrella filter 30 retrieval device of this application reduces the surgical risk of umbrella filter 30 retrieval and reduces long-term complications.

[0043] The recovery sheath 10 is made of materials including, but not limited to, polymers such as PP (Polypropylene), PA (Polyamide), HDPE (High Density Polyethylene), and PEEK (Polyetheretherketone). These polymers possess excellent physicochemical properties, such as high temperature resistance, chemical corrosion resistance, and good biocompatibility. The surface of the recovery sheath 10 made of these polymers is smooth to improve the smoothness of the flow of the umbrella-shaped filter 30 into the recovery sheath 10 from the recovery window 11.

[0044] See again Figure 1 As shown, in some embodiments, the length L1 of the retrieval window 11 along the axial direction of the retrieval sheath 10 is 10mm to 30mm, and the depth H of the retrieval window 11 in the radial direction of the retrieval sheath 10 is 0.55mm to 2.5mm. It should be noted that the depth of the retrieval window 11 in the radial direction of the retrieval sheath 10 can be understood as the depth of the recess of the retrieval window 11 relative to the wall of the retrieval sheath 10.

[0045] For ease of understanding, let's take the example of the recycling sheath 10 being formed by extrusion and the recycling window 11 being formed by cutting.

[0046] When the recycling sheath 10 is formed by extrusion, a recycling window 11 can be cut out on the recycling sheath 10 using a mold. The cutting depth along the radial direction of the recycling sheath 10 is the recess depth of the recycling window 11.

[0047] In the above embodiment, the length L1 of the retrieval window 11 along the axial direction of the retrieval sheath 10 is 10mm to 30mm, and the depth H of the retrieval window 11 in the radial direction of the retrieval sheath 10 is 0.55mm to 2.5mm. This ensures that the size of the retrieval window 11 is not too small to allow the umbrella-shaped filter 30 to enter the retrieval sheath 10 from the retrieval window 11; simultaneously, the retrieval window 11 is not too large to ensure the support performance of the corresponding part of the retrieval sheath 10, facilitating the guidance of the capture device 20 to stably capture the umbrella-shaped filter 30.

[0048] It should be noted that the size of the recovery window 11 is not limited here. For example, in some embodiments, the length L1 of the recovery window 11 along the axial direction of the recovery sheath 10 can be 10mm, 15mm, 20mm, 25mm, or 30mm. The depth H of the recovery window 11 in the radial direction of the recovery sheath 10 can be 0.55mm, 1.05mm, 1.55mm, 2.05mm, or 2.5mm.

[0049] In some embodiments, the distance L2 from the developing section 12 to the distal end of the recovery sheath 10 is 60mm to 70mm. Understandably, since the catcher 20 pulls the umbrella-shaped filter 30 into the recovery sheath 10 via the recovery window 11, the umbrella-shaped filter 30 is located at the distal end of the recovery sheath 10 after entering the recovery sheath 10, meaning the recovery window 11 is located at the distal end of the recovery sheath 10. Furthermore, since the developing section 12 is located at the distal end of the recovery sheath 10 where the recovery window 11 is located, the displacement of the recovery hook 32 along the recovery sheath 10 from the developing section 12 towards the distal end during the process of the catcher 20 pulling the umbrella-shaped filter 30 from the recovery window 11 into the recovery sheath 10 is the length of the umbrella-shaped filter 30 entering the recovery sheath 10. Finally, when the umbrella-shaped filter 30 is completely housed in the recovery sheath 10, the displacement of the recovery hook 32 relative to the developing section 12 towards the distal end is not less than the length of the umbrella-shaped filter 30.

[0050] Based on this, in this embodiment, the distance L2 from the developing section 12 to the distal end of the recovery sheath 10 is 60mm to 70mm. This allows the recovery sheath 10 to cover the umbrella-shaped filter 30, accommodating the need to house the umbrella-shaped filter 30 without being too long and wasting material. Furthermore, with this structural arrangement, since this part of the structure is not too long, when using the recovery sheath 10 to recover the umbrella-shaped filter 30, the recovery window 11 of the recovery sheath 10 can be adjusted to a position closer to the heart, thus accommodating the need to recover the umbrella-shaped filter 30 located closer to the heart.

[0051] It should be noted that the distance from the developing section 12 to the distal end of the recovery sheath 10 can be configured according to the length of the umbrella-shaped filter 30 to be recovered, as long as it can meet the recovery needs of the umbrella-shaped filter 30. For example, in some embodiments, the distance L2 from the developing section 12 to the distal end of the recovery sheath 10 is 60mm, 63mm, 65mm, 66mm, 67mm, 69mm or 70mm.

[0052] In some embodiments, the inner diameter of the retrieval sheath 10 is 3mm to 4mm, and the outer diameter is 4mm to 6mm. This allows the retrieval sheath 10 to have an appropriate inner diameter to meet the retrieval needs of the umbrella-shaped filter 30, avoiding excessive compression of the filter 30 due to an excessively small inner diameter. Simultaneously, by setting the outer diameter of the retrieval sheath 10 to 4mm to 6mm, it accommodates the movement of the retrieval sheath 10 within the blood vessel.

[0053] Understandably, the size of the recovery sheath 10 is sufficient to meet the requirements for retrieval of the umbrella filter 30 within the blood vessel.

[0054] For example, in some embodiments, the inner diameter of the recovery sheath 10 is 3 mm and the outer diameter is 4 mm; or, the inner diameter of the recovery sheath 10 is 3 mm and the outer diameter is 5 mm; or, the inner diameter of the recovery sheath 10 is 4 mm and the outer diameter is 5 mm; or, the inner diameter of the recovery sheath 10 is 4 mm and the outer diameter is 6 mm. The inner and outer diameters of the recovery sheath 10 will not be elaborated further here.

[0055] In some embodiments, the length of the recovery sheath 10 is 550mm to 700mm. For example, the length of the recovery sheath 10 is 550mm, 600mm, 650mm, or 700mm. The length of the recovery sheath 10 is not limited here, as long as it meets the recovery requirements of the umbrella filter 30.

[0056] Accordingly, the size of the capture conduit 23 only needs to be sufficient to allow it to move within the recovery sheath 10 to pull the umbrella-shaped filter 30 into the recovery sheath 10. For example, in some embodiments, the capture conduit 23 has a length of 750 mm to 850 mm, an inner diameter of 0.9 mm to 1.2 mm, and an outer diameter of 1.5 mm to 2.0 mm.

[0057] See again Figure 1 As shown, in some embodiments, the imaging section 12 includes an imaging ring 12a, which is sleeved on the outside of the retrieval sheath 10 or embedded in the inner wall of the retrieval sheath 10. This structural arrangement, where the imaging ring 12a is arranged around the retrieval sheath 10, is not only stable but also clearly indicates its axial position within the retrieval sheath 10. This allows the retrieval sheath 10 to be accurately moved along the blood vessel to a position where the retrieval window 11 is opposite the umbrella filter 30, thereby facilitating the subsequent retrieval operation of the umbrella filter 30.

[0058] Furthermore, the developing ring 12a covers 1 / 3 to 1 / 2 of the circumference of the recovery sheath 10. Thus, the developing ring 12a does not completely encircle the recovery sheath 10. Consequently, the developing ring 12a not only displays the position along the axial direction of the recovery sheath 10, but also shows the current circumferential orientation of the recovery sheath 10, which facilitates accurately aligning the recovery window 11 towards the side where the umbrella filter 30 is located, improving operational convenience.

[0059] It should be noted that the developing ring 12a can be developed under X-rays to indicate the position and orientation of the recovery window 11. The materials of the developing ring 12a include, but are not limited to, platinum-iridium alloy, platinum-tungsten alloy, platinum-nickel alloy, barium sulfate, bismuth trioxide, or tungsten.

[0060] Combination Figure 3As shown, in some embodiments, the retrieval sheath 10 has a bend 13 at the corresponding retrieval window 11. The bend 13 bends toward the side where the retrieval window 11 is located, and the included angle α between the two ends of the bend 13 is 150°~160°. When the umbrella filter 30 is retrieved from the retrieval window 11 to the retrieval sheath 10 using the catcher 20, the bend 13 allows the umbrella filter 30 to enter the retrieval sheath 10 more conveniently from the retrieval window 11 toward the distal end, thereby improving the retrieval convenience of the umbrella filter 30. Based on this angle range, the bend 13 is not too bent (too large an angle) which would hinder the movement of the retrieval sheath 10 within the blood vessel, nor is the bend too small (too small an angle) which would fail to facilitate the entry of the umbrella filter 30 into the retrieval sheath 10.

[0061] It should be noted that the included angle α between the sections of the recovery sheath 10 located at both ends of the bend 13 is not limited here. For example, in some embodiments, the included angle α between the sections of the recovery sheath 10 located at both ends of the bend 13 is 150°, 152°, 153°, 155°, 157°, 159° or 160°.

[0062] In some embodiments, the catcher 20 includes a catching ring 21, a transmission wire 22, a catching guide tube 23, and a torque adjustment assembly 24. The catching ring 21 is connected to the distal end of the transmission wire 22, which passes through the catching guide tube 23. The torque adjustment assembly 24 is located at the proximal end of the catching guide tube 23 and is connected to the proximal end of the transmission wire 22. The torque adjustment assembly 24 is used to axially move the transmission wire 22 relative to the catching guide tube 23 to adjust the size of the catching ring 21.

[0063] It should be noted that, because the torque adjustment component 24 can pull the transmission wire 22 to move axially relative to the capture guide tube 23, the size of the capture ring 21 can be adjusted. Therefore, when using the capture ring 21 to capture the retrieval hook 32 of the umbrella-shaped filter 30, the transmission wire 22 can be moved further away from the capture guide tube 23, increasing the exposed portion of the capture ring 21 at the far end of the capture guide tube 23, thus providing the capture ring 21 with a larger surrounding space to capture the retrieval hook 32.

[0064] Accordingly, after the capture ring 21 captures the retrieval hook 32, the torque adjustment component 24 can be used to pull the guide wire 22 axially towards the proximal end relative to the capture guide tube 23, causing a portion of the structure of the capture ring 21 to retract into the capture guide tube 23. This locks the capture ring 21 onto the retrieval hook 32, reducing the likelihood of the retrieval hook 32 detaching from the capture ring 21. Thus, when the capture device 20 moves distally relative to the retrieval sheath 10, the umbrella-shaped filter 30 can stably move distally from the retrieval window 11 into the retrieval sheath 10.

[0065] Based on this, the capture device 20 with this structure, together with the recovery sheath 10, can stably and safely recover the umbrella-shaped filter 30 into the recovery sheath 10. Thus, the umbrella-shaped filter 30 is recovered when the recovery sheath 10 and the capture device 20 are withdrawn from the body together.

[0066] In some embodiments, the capture catheter 23 is made of nickel-titanium alloy or stainless steel. In this way, the capture catheter 23 can provide sufficient rigidity to provide sufficient axial support when moving distally relative to the retrieval sheath 10, so that the umbrella filter 30 can be retrieved into the retrieval sheath 10 via the femoral vein by the capture ring 21 encircling the retrieval hook 32 of the umbrella filter 30.

[0067] In some embodiments, the femoral vein umbrella filter 30 retrieval device includes a dilator (not shown). The dilator is inserted into the retrieval sheath 10 from its proximal end and is axially movable relative to the retrieval sheath 10. In this embodiment, the dilator can be used to insert the retrieval sheath 10 into the blood vessel together with the retrieval sheath 10, during which the dilator can provide good support for the retrieval sheath 10.

[0068] In addition, the distal end of the dilator is tapered, thereby reducing the chance of scratching the vessel wall VW when the sheath 10 is inserted into the blood vessel using the dilator support.

[0069] The materials used for expanders include, but are not limited to, polymeric materials such as PE (Polyethylene) or PP (Polypropylene).

[0070] Understandably, given that the dilator can be inserted into the retrieval sheath 10 from its proximal end, the dilator can be withdrawn axially from the proximal end of the retrieval sheath 10. Thus, after the retrieval sheath 10 is inserted into the blood vessel using the dilator, the dilator can be removed from the proximal end of the retrieval sheath 10, thereby withdrawing the dilator outside the body. At this point, the retrieval sheath 10 remaining inside the body can form a channel to allow the capture device 20 to enter, and to allow the capture device 20 to pull the umbrella filter 30 distally from the retrieval window 11 relative to the retrieval sheath 10 into the retrieval sheath 10.

[0071] To facilitate understanding, the following will be combined with... Figures 4 to 7 The process of using the femoral vein filter recovery device to recover the umbrella filter 30 according to one embodiment of the present application is described by way of example, but the process of using the femoral vein filter recovery device is not limited thereto.

[0072] The dilator is assembled with the retrieval sheath 10 such that the distal end of the dilator extends from the distal end of the retrieval sheath 10. Then, along the guidewire via the femoral vein approach, the retrieval sheath 10 is guided together with the dilator to the intended location (i.e., the location where the catcher 20 can pull the umbrella filter 30 from the retrieval window 11 to the retrieval sheath 10), for example, with the retrieval hook 32 of the umbrella filter 30 opposite the retrieval window 11; then, the dilator is withdrawn, at which point the retrieval sheath 10 remains in the blood vessel to provide a delivery path for the subsequent retrieval of the umbrella filter 30 by the catcher 20.

[0073] Combination Figure 4 As shown, after the expander is withdrawn, the catcher 20 is introduced along the recovery sheath 10 so that the catcher ring 21 corresponds to the recovery window 11, so as to use the catcher ring 21 to catch the recovery hook 32 of the umbrella filter 30.

[0074] Specifically, in combination Figure 5 As shown, after the capture ring 21 of the capture device corresponds to the retrieval window 11, the torque adjustment component 24 controls the capture ring 21 to fit onto the retrieval hook 32 of the umbrella filter 30. Then, the guide wire 22 moves towards the proximal end relative to the capture guide tube 23, so that the capture ring 21 is pulled into the capture guide tube 23 by the guide wire 22. In this way, the capture ring 21 gradually tightens to lock the retrieval hook 32, making it difficult for the retrieval hook 32 to fall out of the capture ring 21, thereby improving the capture stability of the umbrella filter 30.

[0075] Combination Figure 6 As shown, after the capture device 20 captures the umbrella-shaped filter 30, the guide wire 22 and the capture conduit 23 can be moved together along the retrieval sheath 10 by manipulating the capture device 20, so that the retrieval hook 32 of the umbrella-shaped filter 30 corresponds to the side of the developing ring 12a. In this way, the developing ring 12a is used as a reference point to accurately determine the side of the retrieval window 11 closest to the developing ring 12a.

[0076] Thus, combined Figure 7 As shown, keeping the catcher 20 stationary, the recovery sheath 10 is moved towards the proximal end, thereby completely moving the umbrella-shaped filter 30 into the recovery sheath. In this way, the recovery sheath 10, along with the umbrella-shaped filter 30 and the catcher 20, is withdrawn from the body, thus achieving the recovery of the umbrella-shaped filter 30.

[0077] In summary, the femoral vein umbrella filter retrieval device provided in this application has a retrieval window 11 on the wall of the retrieval sheath 10, and a contrasting section 12 located at the distal end of the retrieval sheath 10 where the retrieval window 11 is located. This contrasting section 12 allows the retrieval sheath 10 to be accurately moved to a suitable position, aligning the retrieval window 11 with the retrieval hook 32 of the umbrella filter 30. Thus, by moving the catcher 20 along the retrieval sheath 10 until the catcher ring 21 aligns with the retrieval hook 32, the retrieval hook 32 can be caught. Furthermore, by manipulating the catcher 20 and the retrieval sheath 10 to move axially relative to each other, the umbrella filter 30 enters the retrieval sheath 10 through the retrieval window 11. The umbrella filter 30 can then be withdrawn from the body along with the retrieval sheath 10 and the catcher 20, completing the retrieval of the umbrella filter 30. Because the entire operation of this transfemoral vein umbrella filter retrieval device can be performed via a venous approach, it avoids the high surgical risk and long-term complications associated with the transjugular vein retrieval of the umbrella filter 30 in related technologies. Therefore, the transfemoral vein umbrella filter retrieval device of this application reduces the surgical risk of umbrella filter 30 retrieval and minimizes long-term complications.

[0078] It should be noted that the above description only illustrates the operation of the femoral vein umbrella filter retrieval device using the umbrella filter 30 as an example. In actual operation, the operation of the femoral vein umbrella filter retrieval device is not limited to this. For example, when pulling the umbrella filter 30 from the retrieval window 11 to the retrieval sheath 10, it is not necessary to keep the catcher 20 stationary while moving the retrieval sheath 10 proximally. Alternatively, keeping the retrieval sheath 10 stationary while moving the catcher 20 distally relative to the retrieval sheath 10 can also achieve the same result of moving the umbrella filter 30 from the retrieval window 11 into the retrieval sheath 10.

[0079] In addition, the fusiform filter can also be recovered via the femoral vein filter recovery device. The operation process for recovering the fusiform filter can refer to the operation process for recovering the umbrella-shaped filter 30 described above, and will not be repeated here.

[0080] It should be noted that, in the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0081] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0082] In this application, unless otherwise expressly specified and limited, the first feature being "on" or "below" the second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium.

[0083] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0084] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A device for recovering filters via the femoral vein, characterized in that, The femoral vein filter retrieval device is used to retrieve filters with a retrieval hook at the distal end, and the femoral vein filter retrieval device includes: A recovery sheath, wherein the wall of the recovery sheath is provided with a recovery window, and the recovery sheath is provided with a developing section, which is located at the distal end of the recovery sheath where the recovery window is located; A catcher, which is axially movable along the recovery sheath, is used to catch the retrieval hook of the filter and pull the filter distally into the recovery sheath via the retrieval window relative to the recovery sheath.

2. The femoral vein filter recovery device according to claim 1, characterized in that, The recovery sheath has a bend at the corresponding recovery window, the bend bends toward the side where the recovery window is located, and the included angle between the tube segments at both ends of the bend is 150°~160°.

3. The femoral vein filter recovery device according to claim 1 or 2, characterized in that, The catcher includes a catch ring, a guide wire, a catch guide tube, and a torque adjustment assembly. The catch ring is connected to the distal end of the guide wire, the guide wire passes through the catch guide tube, and the torque adjustment assembly is located at the proximal end of the catch guide tube and connected to the proximal end of the guide wire. The torque adjustment assembly is used to pull the guide wire to move axially relative to the catch guide tube.

4. The femoral vein filter recovery device according to claim 3, characterized in that, The capture tube is made of nickel-titanium alloy or stainless steel.

5. The femoral vein filter recovery device according to claim 1 or 2, characterized in that, The femoral vein filter retrieval device includes a dilator with a distal tapered end. The dilator is inserted into the retrieval sheath from the proximal end and is axially movable relative to the retrieval sheath.

6. The femoral vein filter recovery device according to claim 1 or 2, characterized in that, The developing section includes a developing ring, which is sleeved on the outside of the recovery sheath or embedded in the inner wall of the recovery sheath.

7. The femoral vein filter recovery device according to claim 6, characterized in that, The developing ring covers 1 / 3 to 1 / 2 of the circumference of the recovery sheath.

8. The femoral vein filter recovery device according to claim 1 or 2, characterized in that, The length of the recovery window along the axial direction of the recovery sheath is 10mm to 30mm, and the depth of the recovery window in the radial direction of the recovery sheath is 0.55mm to 2.5mm.

9. The femoral vein filter recovery device according to claim 8, characterized in that, The distance from the developing section to the distal end of the recovery sheath is 60mm to 70mm.

10. The femoral vein filter recovery device according to claim 9, characterized in that, The inner diameter of the recovery sheath is 3mm~4mm, and the outer diameter is 4mm~6mm.

11. The femoral vein filter recovery device according to claim 1, characterized in that, The material of the recycling sheath is polypropylene, polyamide, high-density polyethylene or polyetheretherketone.

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