Filtering device for inferior vena cava

Abstract

The invention relates to a filtering device for inferior vena cava, belongs to the technical field of medical instruments, and solves the problems that an inferior vena cava filter screen in the prior art is likely to incline and cannot be smoothly taken out from a blood vessel in the implanting operation process. The device comprises a front positioning unit, a filter screen unit and a rear positioning unit, the front positioning unit is sleeved with the filter screen unit, and the filter screen unit is sleeved with the rear positioning unit; and the front positioning unit and the rear positioning unit are used for unfolding and positioning the filter screen unit which is unfolded subsequently. The first positioning point of the front positioning unit and the second positioning point of the rear positioning unit are both located on the center line of the front positioning sleeve, after the filter screen assembly is unfolded, the front positioning sleeve can ensure that the center line of the filter screen assembly coincides with the center line of the inferior vena cava blood vessel, and it is ensured that the filter screen assembly does not incline in the inferior vena cava blood vessel; and the subsequent filter screen assembly can be conveniently and smoothly taken out from the inferior vena cava blood vessel.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a filtering device for the inferior vena cava. Background Art

[0002] Deep vein thrombosis (DVT) in the lower extremities is a common vascular disease, with an increasing incidence. To prevent pulmonary embolism, inferior vena cava filter implantation is a common diagnostic and treatment method currently in widespread clinical use.

[0003] The inferior vena cava filter can effectively intercept deep vein thrombosis in the lower limbs from detaching and entering the pulmonary circulation, thereby preventing the occurrence of pulmonary embolism.

[0004] At present, most long-term inferior vena cava filters used in clinical practice are umbrella-shaped structures. During the implantation process, there is a possibility of tilting, and even the tip of the umbrella structure may stick to the blood vessel wall. When it needs to be removed from the inferior vena cava during a later operation, the tip of the umbrella structure cannot be hooked, and the inferior vena cava filter cannot be removed smoothly. This may subsequently lead to vascular hyperplasia and adhesion, increasing the risk of further open surgery for removal.

[0005] Currently, there is no clinically effective solution to prevent problems such as tilting, angulation, and wall adhesion during inferior vena cava filter implantation. Summary of the Invention

[0006] In view of the above-mentioned deficiencies in the prior art, the present invention provides a filtering device for the inferior vena cava, which is used to solve the problem in the prior art that the inferior vena cava filter may tilt during the implantation operation and cannot be smoothly removed from the blood vessel.

[0007] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0008] The present invention provides a filtering device for the inferior vena cava, comprising a front positioning unit, a filter unit and a rear positioning unit, wherein the filter unit is sleeved on the front positioning unit, and the rear positioning unit is sleeved on the filter unit; the front positioning unit and the rear positioning unit are both used to be deployed in the inferior vena cava to position the filter unit for subsequent deployment, and the inferior vena cava filter of the filter unit can remain non-tilted during the implantation operation and can subsequently be smoothly removed from the inferior vena cava blood vessel.

[0009] Furthermore, the front positioning unit includes a front positioning branch and a push-pull bar, the front positioning branch is connected to one end of the push-pull bar, and the other end of the push-pull bar is a free end.

[0010] Furthermore, the front positioning unit further includes a front positioning sleeve, the front positioning branches and the push-pull strips are both arranged in the front positioning sleeve, and the filter unit is arranged on the front positioning sleeve.

[0011] Furthermore, the front positioning branches are provided in plurality and are evenly distributed circumferentially along the center line of the push-pull bar.

[0012] Furthermore, the front positioning branches are elastic positioning branches, which can be pushed out of the front positioning sleeve by the push-pull strip and radially expanded.

[0013] Furthermore, the push-pull strip is a steel wire rope.

[0014] Furthermore, the filter unit includes a filter assembly, a filter push-pull sleeve and a filter protective tube. The filter assembly is detachably connected to the filter push-pull sleeve. The filter assembly and the filter push-pull sleeve are both sleeved on the front positioning sleeve, and the filter assembly and the filter push-pull sleeve are both arranged in the filter protective tube.

[0015] Furthermore, the rear positioning unit includes a rear positioning branch, a rear positioning sleeve and a rear protective tube. The rear positioning branch and the rear positioning sleeve are both arranged in the rear protective tube, and the rear positioning branch is connected to one end of the rear positioning sleeve.

[0016] Furthermore, the rear positioning branches are provided in plurality and are evenly distributed circumferentially on the end surface of the rear positioning sleeve.

[0017] Furthermore, the rear positioning branches are elastic positioning branches, which can be pushed out of the rear protective tube by the rear positioning sleeve and radially expanded.

[0018] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0019] (1) The first positioning point of the front positioning unit and the second positioning point of the rear positioning unit are both on the midline of the front positioning sleeve. After the front positioning branches and the rear positioning branches are unfolded, the midline of the front positioning sleeve can coincide with the midline of the inferior vena cava. After the filter assembly is unfolded, the front positioning sleeve can ensure that the midline of the filter assembly coincides with the midline of the inferior vena cava, ensuring that the filter assembly will not be skewed in the inferior vena cava, thereby facilitating the subsequent smooth removal of the filter assembly from the inferior vena cava.

[0020] (2) The first sleeve and the second sleeve of the present invention jointly position the filter assembly, further ensuring that the filter assembly will not be skewed in the inferior vena cava; the filter assembly is shaped like a date pit, and the contact area between the filter branches and the blood vessel wall is increased, making the placement of the filter assembly in the blood vessel more stable;

[0021] (3) The tenon of the present invention can be inserted into the connecting transverse groove and connected to the connecting transverse groove, and prevent the connecting sleeve from being separated from the first sleeve; one end of the leaf spring is connected to the tenon, and the other end of the leaf spring is connected to the tenon groove. The leaf spring is used to make the tenon pop out of the tenon groove and keep the tenon connected to the connecting transverse groove, thereby preventing the connecting sleeve from being separated from the first sleeve;

[0022] (4) The user rotates the sleeve body of the present invention, which can drive the connecting sleeve to rotate, and the unlocking slope can be connected to the inner wall of the first sleeve. The connecting sleeve is further rotated, and under the restriction of the inner wall of the first sleeve, the tenon body is pressed into the tenon groove until the tenon body is separated from the connecting transverse groove; at this time, the user pulls the sleeve body out of the body, and the connecting sleeve can be axially separated from the first sleeve, and the sleeve body can be removed from the vein, completing the filter assembly placement operation;

[0023] (5) When the connecting sleeve of the present invention is rotated, the tenon can be ejected by the leaf spring and connected to the slot; the user can feel a clear sense of segmentation and a sense of resistance when rotating the connecting sleeve, so that the user can confirm that the tenon body is disengaged from the connecting transverse groove, and the axially arranged slot can prevent the tenon from being connected to the connecting transverse groove, and guide the connecting sleeve to axially disengage from the first sleeve, which is convenient for the user to operate.

[0024] In the present invention, the above-mentioned technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of the present invention will be described in the following content, and some advantages will become apparent from the description or be learned through practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained as particularly pointed out in the text and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the overall structure of the filtering device of the present invention;

[0026] Figure 2 Schematic diagram of the overall structure of the filter assembly of Example 1;

[0027] Figure 3 Schematic diagram of the overall structure of the filter assembly of Example 2;

[0028] Figure 4 This is a schematic diagram of the overall structure of the filter push-pull sleeve;

[0029] Figure 5 Schematic diagram of the overall structure connecting the tenon and the spring.

[0030] Reference numerals:

[0031] 1-Front positioning unit; 2-Filter unit; 3-Rear positioning unit; 11-Front positioning branch; 12-Push-pull bar; 13-Front positioning sleeve; 21-Filter assembly; 22-Filter push-pull sleeve; 23-Filter protective tube; 31-Rear positioning branch; 32-Rear positioning sleeve; 33-Rear protective tube; 211-First sleeve; 212-Filter branch; 213-Second sleeve; 214-Connecting transverse groove; 215-Card slot; 221-Sleeve body; 222-Connecting sleeve; 223-Tension; 224-Leaf spring; 2231-Tension body; 2232-Locking plane; 2233-Unlocking slope. DETAILED DESCRIPTION

[0032] The specific embodiments of the present invention are described below to facilitate understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the appended claims, these changes are obvious, and all inventions and creations utilizing the concepts of the present invention are protected.

[0033] Example 1

[0034] A specific embodiment of the present invention, as Figure 1 As shown, a filtering device for the inferior vena cava (hereinafter referred to as the filtering device) includes a front positioning unit 1, a filter unit 2, and a rear positioning unit 3. The filter unit 2 is mounted on the front positioning unit 1, and the rear positioning unit 3 is mounted on the filter unit 2. The front positioning unit 1 and the rear positioning unit 3 are both used to deploy in the inferior vena cava to locate the midline of the inferior vena cava. The filter unit 2 is then deployed, and the midline of the filter unit 2 can coincide with the midline of the inferior vena cava. The inferior vena cava filter of the filter unit 2 can remain stable during the implantation process and can be successfully removed from the inferior vena cava.

[0035] Preferably, if Figure 1As shown, the front positioning unit 1 includes a front positioning branch 11, a push-pull bar 12 and a front positioning sleeve 13. The front positioning branch 11 and the push-pull bar 12 are both arranged in the front positioning sleeve 13. The front positioning branch 11 is connected to one end of the push-pull bar 12, which is the connecting end. The other end of the push-pull bar 12 is the free end. The filter unit 2 is arranged on the front positioning sleeve 13, and the midpoint of the connecting end of the push-pull bar 12 is the first positioning point. There are multiple front positioning branches 11, and they are evenly distributed circumferentially on the push-pull bar 12 along the center line of the push-pull bar 12. The front positioning branch 11 is an elastic positioning branch that can be pushed out of the front positioning sleeve 13 by the push-pull bar 12 and radially expanded so that the first positioning point is close to or even coincides with the midline of the inferior vena cava, thereby positioning the filter unit 2 and the rear positioning unit 3. The front positioning branches 11 can also be pulled by the push-pull strips 12 and then stored in the front positioning sleeve 13, and then the front positioning unit 1 as a whole can pass through the filter unit 2 and be taken out of the human body.

[0036] Preferably, the push-pull strip 12 is a steel wire rope.

[0037] Preferably, the filter unit 2 includes a filter assembly 21, a filter push-pull sleeve 22, and a filter protective tube 23. The filter assembly 21 and the filter push-pull sleeve 22 are detachably connected. The filter assembly 21 and the filter push-pull sleeve 22 are both sleeved on the front positioning sleeve 13, and the filter assembly 21 and the filter push-pull sleeve 22 are both disposed within the filter protective tube 23. The filter protective tube 23 is used to accommodate the filter assembly 21 and the filter push-pull sleeve 22. The filter push-pull sleeve 22 is used to push the filter assembly 21 out of the filter protective tube 23. The filter assembly 21 can be radially expanded to filter blood clots in the inferior vena cava.

[0038] Preferably, the rear positioning unit 3 includes a rear positioning branch 31, a rear positioning sleeve 32, and a rear protective tube 33. The rear positioning branch 31 and the rear positioning sleeve 32 are both disposed within the rear protective tube 33. The rear positioning branch 31 and one end of the rear positioning sleeve 32 are connected, and the center point of this end face is the second positioning point. A plurality of rear positioning branches 31 are provided, and are evenly distributed circumferentially around the second positioning point on the end face of the rear positioning sleeve 32. The rear positioning branches 31 are elastic positioning branches that can be pushed out of the rear protective tube 33 by the rear positioning sleeve 32 and radially expanded so that the second positioning point approaches or even coincides with the midline of the inferior vena cava. The first positioning point and the second positioning point are both on the center line of the front positioning sleeve 13. After the front positioning branch 11 and the rear positioning branch 31 are unfolded, the center line of the front positioning sleeve 13 can coincide with the center line of the inferior vena cava. After the filter assembly 21 is unfolded, the front positioning sleeve 13 can ensure that the center line of the filter assembly 21 coincides with the center line of the inferior vena cava, ensuring that the filter assembly 21 will not be skewed in the inferior vena cava, thereby facilitating the subsequent removal of the filter assembly 21 from the inferior vena cava.

[0039] The rear positioning branches 31 can also be pulled by the rear positioning sleeve 32 and then stored in the front and rear protective tubes 33. The rear positioning unit 3 as a whole can be taken out of the blood vessel.

[0040] Preferably, Figure 2 As shown, the filter assembly 21 includes a first sleeve 211 and filter branches 212. The filter branches 212 are arranged on the end face of the first sleeve 211, and the center point of this end face is the second positioning point. The first sleeve 211 is sleeved on the front positioning sleeve 13 and is detachably connected to the filter push-pull sleeve 22. There are multiple filter branches 212, and they are evenly distributed on the first sleeve 211 along the circumference of the end face of the first sleeve 211. The filter branches 212 are elastic filter branches. The first sleeve 211 can be pushed out of the front filter protective tube 23 by the filter push-pull sleeve 22, and the filter branches 212 can be radially expanded.

[0041] The filter assembly 21 is funnel-shaped or umbrella-shaped and is used to intercept thrombus. The center line of the first sleeve 211 can coincide with the center line of the inferior vena cava, ensuring that the filter assembly 21 will not be skewed in the inferior vena cava and the first sleeve 211 will not stick to the blood vessel wall, making it easier for the subsequent filter assembly 21 to be removed smoothly from the inferior vena cava.

[0042] Compared with the prior art, the first positioning point of the front positioning unit 1 and the second positioning point of the rear positioning unit 3 are both on the center line of the front positioning sleeve 13. After the front positioning branches 11 and the rear positioning branches 31 are unfolded, the center line of the front positioning sleeve 13 can coincide with the center line of the inferior vena cava. After the filter assembly 21 is unfolded, the front positioning sleeve 13 can ensure that the center line of the filter assembly 21 coincides with the center line of the inferior vena cava, ensuring that the filter assembly 21 will not be skewed in the inferior vena cava, and the first sleeve 211 will not stick to the blood vessel wall, so that the subsequent filter assembly 21 can be smoothly removed from the inferior vena cava.

[0043] Example 2:

[0044] The umbrella-shaped filter assembly 21 has a great risk of tilting, such as Figure 3 As shown, in order to place the filter assembly 21 more firmly in the inferior vena cava, based on Example 1, this embodiment improves the filter assembly 21 so that the filter assembly 21 is placed more firmly in the inferior vena cava.

[0045] Preferably, the filter assembly 21 further includes a second sleeve 213, which is sleeved onto the front positioning sleeve 13. One end of the filter branch 212 is connected to the first sleeve 211, and the other end of the filter branch 212 is connected to the second sleeve 213. The filter assembly 21 is shaped like a date pit. The first sleeve 211 and the second sleeve 213 jointly position the filter assembly 21, further ensuring that the filter assembly 21 does not tilt within the inferior vena cava. Furthermore, the contact area between the filter branch 212 and the vessel wall is increased, making the filter assembly 21 more securely positioned within the vessel.

[0046] Compared with Example 1, the filter assembly 21 is in the shape of a date pit, and the first sleeve 211 and the second sleeve 213 jointly position the filter assembly 21, further ensuring that the filter assembly 21 will not be skewed in the inferior vena cava; and the contact area between the filter branches 212 and the blood vessel wall is increased, and the filter assembly 21 is placed more firmly in the blood vessel.

[0047] Example 3:

[0048] Before the filter assembly 21 is placed, the filter assembly 21 and the filter push-pull sleeve 22 need to be firmly connected; after the filter assembly 21 is placed, the filter assembly 21 and the filter push-pull sleeve 22 need to be quickly disconnected. This embodiment improves the structure of the filter assembly 21 and the filter push-pull sleeve 22 of the filter unit 2 based on the first or second embodiment. Before the filter assembly 21 is placed, the filter assembly 21 and the filter push-pull sleeve 22 can be firmly connected; after the filter assembly 21 is placed, the filter assembly 21 and the filter push-pull sleeve 22 can be quickly disconnected.

[0049] Preferably, if Figure 3 As shown, the filter assembly 21 further includes a connecting transverse groove 214 , which is circumferentially arranged on the wall of the first sleeve 211 .

[0050] Preferably, if Figure 4 As shown, the filter screen push-pull sleeve 22 includes a sleeve body 221, a connecting sleeve 222, a tenon 223, and a leaf spring 224. The connecting sleeve 222 is connected to the sleeve body 221. A tenon groove (not shown) is provided on the outer wall of the connecting sleeve 222. The tenon 223 and the leaf spring 224 are both disposed on the tenon groove. The tenon 223 can be inserted into and connected to the connecting transverse groove 214, and prevents the connecting sleeve 222 from separating from the first sleeve 211. One end of the leaf spring 224 is connected to the tenon 223, and the other end of the leaf spring 224 is connected to the tenon groove. The leaf spring 224 is used to eject the tenon 223 from the tenon groove and maintain the tenon 223 connected to the connecting transverse groove 214, preventing the connecting sleeve 222 from separating from the first sleeve 211.

[0051] Preferably, if Figure 5As shown, the leaf spring 224 is an arc-shaped leaf spring, and the leaf spring 224 can provide axial support for the tenon 223 .

[0052] Preferably, the latch 223 is a wedge-shaped latch and includes a latch body 2231 having a locking flat surface 2232 and an unlocking slope 2233. The locking flat surface 2232 is capable of abutting the connecting transverse groove 214 and preventing the latch 223 from axially disengaging from the first sleeve 211. When the user twists the circumferential sleeve body 221, the connecting sleeve 222 is rotated circumferentially, and the unlocking slope 2233 engages the inner wall of the first sleeve 211. Further rotation of the connecting sleeve 222 forces the latch body 2231 into the latch groove, constrained by the inner wall of the first sleeve 211, until the latch body 2231 disengages from the connecting transverse groove 214. At this point, the user pulls the sleeve body 221 outward, allowing the connecting sleeve 222 to axially disengage from the first sleeve 211 and be removed from the vein, completing the placement procedure for the filter assembly 21.

[0053] Preferably, if Figure 3 As shown, the filter assembly 21 further includes a slot 215, which is axially disposed on the inner wall of the first sleeve 211 and is disposed opposite the midpoint of the connecting transverse groove 214. As the connecting sleeve 222 continues to rotate, the tenon 223 is ejected by the leaf spring 224 and connected to the slot 215. The user can feel a distinct sense of movement and resistance when rotating the connecting sleeve 222, confirming that the tenon body 2231 is disengaged from the connecting transverse groove 214. The axially disposed slot 215 prevents the tenon 223 from connecting to the connecting transverse groove 214 and guides the connecting sleeve 222 to axially disengage from the first sleeve 211.

[0054] Compared with embodiment 1 or 2, the tenon 223 can be inserted into the connecting transverse groove 214 and connected to the connecting transverse groove 214, and prevent the connecting sleeve 222 from being separated from the first sleeve 211; one end of the leaf spring 224 is connected to the tenon 223, and the other end of the leaf spring 224 is connected to the tenon groove. The leaf spring 224 is used to make the tenon 223 pop out of the tenon groove and keep the tenon 223 connected to the connecting transverse groove 214 to prevent the connecting sleeve 222 from being separated from the first sleeve 211; the user rotates the sleeve body 221 to drive the connecting sleeve 222 to rotate, and the unlocking slope 2233 can be connected to the inner wall of the first sleeve 211. Further rotation of the connecting sleeve 222 will cause the tenon body 2231 to be pressed under the restriction of the inner wall of the first sleeve 211. The sleeve 222 is inserted into the mortise groove until the mortise body 2231 is disengaged from the connecting transverse groove 214; at this time, the user pulls the sleeve body 221 outside the body, the connecting sleeve 222 can axially disengage from the first sleeve 211, and the sleeve body 221 can be removed from the venous blood vessel, completing the surgical operation of placing the filter assembly 21; rotating the connecting sleeve 222, the mortise 223 can be ejected by the leaf spring 224 and connected to the mortise groove 215; the user can feel an obvious sense of paragraph and a sense of resistance when rotating the connecting sleeve 222, so that the user can confirm that the mortise body 2231 is disengaged from the connecting transverse groove 214, and the axially arranged mortise groove 215 can prevent the mortise 223 from connecting to the connecting transverse groove 214, and guide the connecting sleeve 222 to axially disengage from the first sleeve 211.

[0055] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. A filtering device for the inferior vena cava, characterized in that: The invention comprises a front positioning unit (1), a filter unit (2) and a rear positioning unit (3), wherein the filter unit (2) is sleeved on the front positioning unit (1), and the rear positioning unit (3) is sleeved on the filter unit (2); the front positioning unit (1) and the rear positioning unit (3) are both used to be first deployed in the inferior vena cava to position the filter unit (2) that is subsequently deployed; the inferior vena cava filter of the filter unit (2) can remain non-tilted during the implantation operation and can be smoothly removed from the inferior vena cava blood vessel subsequently.

2. The filtering device for the inferior vena cava according to claim 1, characterized in that: The front positioning unit (1) comprises a front positioning branch (11) and a push-pull strip (12); the front positioning branch (11) is connected to one end of the push-pull strip (12); and the other end of the push-pull strip (12) is a free end.

3. The filtering device for the inferior vena cava according to claim 2, characterized in that: The front positioning unit (1) further comprises a front positioning sleeve (13), the front positioning branches (11) and the push-pull strips (12) are both arranged in the front positioning sleeve (13), and the filter unit (2) is arranged on the front positioning sleeve (13).

4. The filtering device for the inferior vena cava according to claim 3, characterized in that: The front positioning branches (11) are arranged in a plurality and are evenly distributed circumferentially on the push-pull strip (12) along the center line of the push-pull strip (12).

5. The filtering device for the inferior vena cava according to claim 4, characterized in that: The front positioning branches (11) are elastic positioning branches that can be pushed out of the front positioning sleeve (13) by the push-pull strips (12) and radially expanded.

6. The filtering device for the inferior vena cava according to claim 2, characterized in that: The push-pull strip (12) is a steel wire rope.

7. The filtering device for the inferior vena cava according to claim 1, characterized in that: The rear positioning unit (3) comprises a rear positioning branch (31), a rear positioning sleeve (32) and a rear protective tube (33).

8. The filtering device for the inferior vena cava according to claim 7, characterized in that: The rear positioning branch (31) and the rear positioning sleeve (32) are both arranged in the rear protective tube (33), and one end of the rear positioning branch (31) and the rear positioning sleeve (32) are connected.

9. The filtering device for the inferior vena cava according to claim 8, characterized in that: The rear positioning branches (31) are provided in plurality and are evenly distributed circumferentially on the end surface of the rear positioning sleeve (32).

10. The filtering device for the inferior vena cava according to claim 9, characterized in that: The rear positioning branches (31) are elastic positioning branches that can be pushed out of the rear protective tube (33) by the rear positioning sleeve (32) and radially expanded.

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