Vein filter and recovery device thereof

Abstract

The invention provides a vein filter and a recovery device thereof, the vein filter comprises a recovery mechanism and a filtering mechanism, the filtering mechanism is composed of a plurality of filtering arms, the roots of the filtering arms are connected with the recovery mechanism, the recovery mechanism comprises a funnel part, a fixing part and a connecting part, and the funnel part, the fixing part and the connecting part are fixedly connected in sequence; a funnel cavity is formed in the funnel part, an expansion fixing cavity is formed in the fixing part, and a passing cavity is formed in the connecting part; the wide-opening end of the funnel cavity is communicated with the outside, the narrow-opening end of the funnel cavity is communicated with one end of the expansion fixing cavity, and the other end of the expansion fixing cavity is communicated with one end of the passing cavity; the maximum inner diameter of the expansion fixing cavity is larger than the inner diameter of the narrow opening end of the funnel cavity. The funnel type recovery mechanism is matched with the catheter provided with the balloon, so that the technical problems in the prior art that the filter is difficult to take out when inclining and the recovery operation is difficult are solved.

Description

Technical Field

[0001] The present invention relates to the field of necessities of human life, in particular to the field of filters that can be implanted into blood vessels, in particular to a venous filter and a recovery device thereof. Background Art

[0002] A venous filter is a medical device implanted in the inferior vena cava. Its primary function is to capture large thrombi that have dislodged from the deep veins of the lower extremities or pelvis, preventing them from traveling with the bloodstream to the pulmonary arteries, thereby preventing fatal pulmonary embolism. As a temporary protective measure, it is not a substitute for anticoagulant therapy. Anticoagulant therapy should be resumed as soon as conditions permit, and the filter should be removed promptly after the risk period has passed.

[0003] In the prior art, a venous filter is inserted into a vein during vascular surgery. A retrieval hook is usually provided at the proximal end of the filter, and the filter is removed by hooking the retrieval hook with a snare. However, this type of venous filter has the following drawbacks:

[0004] 1. Difficulty in Removal of a Tilted Venous Filter: Venous filters often tilt within the vein, resulting in malposition. If the open side of the retrieval hook is in close contact with the vessel wall during this tilted state, it can be extremely difficult to remove the filter with a snare. A retained venous filter may gradually dislodge from its original position, sliding into a more distal vein or even the heart (rare but extremely dangerous). This necessitates more complex methods for filter removal (such as catheter coiling, sheath-assisted procedures), or even laparotomy. With current medical technology, filter removal failure is a relatively common occurrence.

[0005] 2. The retrieval operation is difficult: the snare needs to be accurately hooked into the opening of the retrieval hook before the filter can be removed. However, the opening of the retrieval hook is extremely small. The doctor must simultaneously control the axial and radial positions of the front end of the snare to accurately hook the snare into the opening, which requires a high level of precision in the doctor's operation. Summary of the Invention

[0006] The object of the present invention is to provide a venous filter and a recovery device thereof, which are intended to solve the technical problems in the prior art that the filter is difficult to remove when tilted and the recovery operation is difficult.

[0007] The present invention provides a venous filter and a recovery device thereof, comprising a venous filter and a recovery device. The venous filter and the recovery device form a venous filter set device for use in conjunction with each other.

[0008] The venous filter provided by the present invention includes a recovery mechanism and a filtering mechanism, wherein the filtering mechanism is composed of multiple filter arms, the roots of the filter arms are connected to the recovery mechanism, and the recovery mechanism includes a funnel part, a fixing part and a connecting part, and the funnel part, the fixing part and the connecting part are fixedly connected in sequence; a funnel cavity is provided in the funnel part, an expansion and fixing cavity is provided in the fixing part, and a passing cavity is provided in the connecting part; the wide mouth end of the funnel cavity is connected to the outside world, the narrow mouth end of the funnel cavity is connected to one end of the expansion and fixing cavity, and the other end of the expansion and fixing cavity is connected to one end of the passing cavity; the maximum inner diameter of the expansion and fixing cavity is greater than the inner diameter of the narrow mouth end of the funnel cavity.

[0009] Furthermore, the expansion and fixing cavity is a spherical cavity.

[0010] Furthermore, the other end of the through cavity is communicated with the outside.

[0011] Furthermore, a plurality of observation slits are provided on the side wall of the fixing portion.

[0012] Furthermore, the filtering mechanism is cage-shaped, and a recovery mechanism is provided at both ends of the filtering mechanism.

[0013] The present invention also provides a recovery device that is compatible with the above-mentioned venous filter, including a recovery mechanism, the recovery mechanism including a catheter, a balloon provided at the front of the catheter, and a joint provided at the rear end of the catheter; an injection cavity is provided in the catheter, a capsule cavity is provided in the balloon, the front end of the injection cavity is connected to the capsule cavity, and the rear end of the injection cavity is connected to the joint; the joint is connected to the injection end of the external syringe; the outer wall of the inflated balloon abuts against the inner wall of the expansion and fixing cavity, and also includes a sheath tube, the inner diameter of the sheath tube is larger than the outer diameter of the wide-mouth end of the funnel cavity.

[0014] Furthermore, developing points are provided at both ends of the balloon.

[0015] Furthermore, a medium is provided in the capsule cavity, and the medium is a developer.

[0016] The present invention also provides a venous filter set device, including a venous filter and a recovery device, the venous filter and the recovery device are used in combination, the venous filter includes a recovery mechanism and a filtering mechanism, the filtering mechanism is composed of a plurality of filter arms, the roots of the filter arms are fixedly connected to the bottom of the recovery mechanism; the recovery mechanism includes a funnel part, a fixing part and a connecting part, the funnel part, the fixing part and the connecting part are fixedly connected in sequence; a funnel cavity is provided in the funnel part, an expansion fixing cavity is provided in the fixing part, and a passing cavity is provided in the connecting part; the wide end of the funnel cavity is communicated with the outside world, and the narrow end of the funnel cavity is connected to the expansion fixing cavity One end is connected, and the other end of the expansion and fixing cavity is connected with one end of the passing cavity; the maximum inner diameter of the expansion and fixing cavity is larger than the inner diameter of the narrow end of the funnel cavity; the recovery device includes a catheter, a balloon is provided at the front of the catheter, and a joint is provided at the rear end of the catheter; an injection cavity is provided in the catheter, a capsule cavity is provided in the balloon, the front end of the injection cavity is connected with the capsule cavity, and the rear end of the injection cavity is connected with the joint; the joint is connected to the injection end of the external syringe; the outer wall of the balloon after expansion abuts against the inner wall of the expansion and fixing cavity; and it also includes a sheath tube, the inner diameter of the sheath tube is larger than the outer diameter of the wide end of the funnel cavity.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. The present invention inserts a catheter with a balloon into the retrieval mechanism, and after the balloon is inflated in the expansion and fixing cavity, it is fixed to the venous filter and removed. The funnel opens at the center, not at an offset opening like a retrieval hook, and is not likely to be affected by the tilt of the venous filter, significantly reducing the probability of the venous filter being unable to be removed due to tilt.

[0019] 2. The funnel of the present invention has a larger inner diameter at its wide opening, making it easier to insert the front end of the catheter into the funnel. The doctor simply aligns the catheter with the funnel and pushes it forward to connect the catheter to the venous filter. Compared to the existing method of inserting a snare into a retrieval hook, the present invention only requires alignment and forward insertion of the catheter. The snare, on the other hand, needs to be precisely aligned with the opening of the retrieval hook, moved laterally into the opening, and then withdrawn to connect with the retrieval hook. Furthermore, the snare could potentially dislodge from the retrieval hook during the retraction process. This present invention significantly reduces the difficulty of connection and fixation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 .Schematic diagram of the structure of the venous filter in Example 1 of the present invention.

[0021] Figure 2 . Schematic diagram of the cross-sectional structure of the venous filter in Example 1 of the present invention.

[0022] Figure 3.Schematic diagram of the structure of the recovery device in Example 1 of the present invention.

[0023] Figure 4 . Schematic diagram of the cross-sectional structure of the recovery device in Example 1 of the present invention.

[0024] Figure 5 . Schematic diagram of the balloon deflated state of the recovery device in Example 1 of the present invention.

[0025] Figure 6 . Schematic diagram of the use steps of Example 1 of the present invention Figure 1 .

[0026] Figure 7 . Schematic diagram of the use steps of Example 1 of the present invention Figure 2 .

[0027] Figure 8 . Schematic diagram of the use steps of Example 1 of the present invention Figure 3 .

[0028] Figure 9 . Schematic diagram of the use steps of Example 1 of the present invention Figure 4 .

[0029] Figure 10 .Schematic diagram of the structure of Example 2 of the present invention.

[0030] In the figure: 1. Retrieval mechanism; 101. Funnel part; 102. Fixing part; 103. Connecting part; 104. Observation slit; 105. Funnel cavity; 106. Expansion and fixing cavity; 107. Passing cavity; 2. Filtering mechanism; 3. Retrieval device; 301. Catheter; 302. Balloon; 303. Injection cavity; 304. Balloon cavity; 305. Development point; 4. Connector; 5. Sheath. DETAILED DESCRIPTION

[0031] The present invention will be further described in the following examples, but are not intended to limit the present invention.

[0032] Example 1

[0033] like Figure 1As shown, this embodiment provides a venous filter and a recovery device thereof. The venous filter includes a recovery mechanism 1 and a filtering mechanism 2; the filtering mechanism 2 is composed of a plurality of filter arms, and the root of the filter arm is fixedly connected to the recovery mechanism 1. The recovery mechanism 1 includes a funnel portion 101, a fixing portion 102 and a connecting portion 103, and the funnel portion 101, the fixing portion 102 and the connecting portion 103 are fixedly connected in sequence. The funnel portion 101 is funnel-shaped, with one end being a wide-mouth end and the other end being a narrow-mouth end, which is convenient for the catheter 301 to penetrate. The fixing portion 102 is spherical and is used to be fixedly connected to the balloon 302 of the recovery mechanism 1 described below. The connecting portion 103 is used to connect the filter arm, and the root of the filter arm is fixedly connected to the bottom of the connecting portion 103.

[0034] like Figure 2 As shown, a funnel cavity 105 is provided within the funnel portion 101, an expansion and fixation cavity 106 is provided within the fixation portion 102, and the expansion and fixation cavity 106 is a spherical cavity. A through cavity 107 is provided within the connection portion 103. The wide end of the funnel cavity 105 communicates with the outside world, the narrow end of the funnel cavity 105 communicates with one end of the expansion and fixation cavity 106, and the other end of the expansion and fixation cavity 106 communicates with one end of the through cavity 107. The other end of the through cavity 107 communicates with the outside world. The maximum inner diameter of the expansion and fixation cavity 106 is larger than the inner diameter of the narrow end of the funnel cavity 105.

[0035] like Figures 3 to 5 As shown, the device comprises a retrieval device 3, which includes a catheter 301. A balloon 302 is provided at the front of the catheter 301, and a connector 4 is provided at the rear end of the catheter 301. In the treatment of venous thromboembolism (VTE), particularly deep vein thrombosis (DVT), balloon catheters are important tools in vascular interventional procedures, primarily used to assist with catheter-directed thrombolysis and mechanical thrombus removal, as well as to address potential venous stenosis discovered after thrombus removal. Balloon catheters for intravenous use are mature technology, and the deflated balloon 302 allows for easy intravascular movement, demonstrating its feasibility. However, in the present invention, they are used solely as a venous filter removal device.

[0036] The catheter 301 is provided with an injection lumen 303, and the balloon 302 is provided with a capsule lumen 304. The front end of the injection lumen 303 communicates with the capsule lumen 304, and the rear end of the injection lumen 303 communicates with the connector 4. The connector 4 is connected to the injection end of an external syringe, which can be a syringe. The outer wall of the inflated balloon 302 abuts the inner wall of the expansion and fixation lumen 106, and the maximum outer diameter of the inflated balloon 302 is larger than the inner diameter of the narrow end of the funnel lumen 105. The balloon 302 can be stuck in the expansion and fixation lumen 106, and the catheter 301 is pulled to move the venous filter. The catheter 301 also includes a sheath 5, whose inner diameter is larger than the outer diameter of the wide end of the funnel lumen 105. The catheter 301 drags the venous filter into the sheath 5, causing the multiple filter arms to converge and contract, and the venous filter is withdrawn from the blood vessel along with the sheath 5.

[0037] In this embodiment, a plurality of observation slits 104 are provided on the side wall of the fixing portion 102. The observation slits 104 are connected to the expansion fixing cavity 106. Through the observation slits 104, the distribution of the developer in the balloon 302 can be conveniently observed under X-ray equipment, thereby understanding the degree of expansion of the balloon 302.

[0038] The balloon 302 is also provided with developing points at both ends. The developing points are developer embedded in the catheter 301, thereby further facilitating the observation of the position of the balloon 302 under X-ray equipment.

[0039] The medium injected by the syringe into the balloon 302 through the injection cavity 303 is a developer, which makes it easier to see the position of the balloon 302 during development and facilitates the expansion of the balloon 302 after placing it in the expansion and fixing cavity 106.

[0040] The usage of this embodiment:

[0041] like Figure 6 As shown, when a venous filter is implanted in a vein and needs to be removed, a catheter 301 is placed within the sheath 5 and introduced from the proximal end of the vein. With the aid of X-ray observation, the distal end of the catheter 301 is extended from the sheath and positioned near the opening of the infundibulum 105 of the retrieval mechanism 1, where it is aligned with the opening. The balloon 302 on the catheter 301 is now deflated.

[0042] like Figure 7 As shown, the catheter 301 continues to be advanced until the balloon 302 is positioned within the inflation fixation lumen 106 .

[0043] like Figure 8 、 Figure 9 As shown, an external syringe injects contrast agent into injection chamber 303 via connector 4. The contrast agent enters balloon cavity 304 through injection chamber 303, causing balloon cavity 304 to expand. The outer wall of the inflated balloon 302 abuts the inner wall of expansion and fixation chamber 106, thereby securing catheter 301 to the venous filter. The injected contrast agent allows X-ray equipment to clearly visualize the expansion of balloon 302, confirming its proper expansion. Finally, catheter 301 is pulled, dragging the venous filter into sheath 5. The multiple filter arms converge and contract, and the venous filter, along with sheath 5, is withdrawn from the blood vessel.

[0044] Example 2

[0045] like Figure 10As shown, this embodiment is a preferred version of Example 1. The filter mechanism 2 is cage-type, with a recovery mechanism 1 provided at each end. This cage-type filter mechanism 2 is prior art, similar to the filter mechanisms of the Cordis / Condis OPTEASE inferior vena cava filter and the Illicium vena cava filter of Weixin Medical. The cage-type structure is characterized by excellent self-neutrality, improved thrombus capture rate, and the ability to maintain long-term patency of the inferior vena cava. In this embodiment, a recovery mechanism 1, described in Example 1, is provided at each closed end of the cage-type filter mechanism 2. The funnel openings of the two recovery mechanisms face opposite directions, thereby achieving recovery at both ends of the venous filter.

[0046] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that it is still possible to modify the technical solutions described in the aforementioned embodiments, or to make equivalent replacements for some of the technical features therein; and these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A venous filter, comprising a recovery mechanism (1) and a filtering mechanism (2), wherein the filtering mechanism (2) is composed of a plurality of filter arms, the roots of the filter arms being fixedly connected to the bottom of the recovery mechanism (1), characterized in that: The recovery mechanism (1) comprises a funnel portion (101), a fixing portion (102), and a connecting portion (103), wherein the funnel portion (101), the fixing portion (102), and the connecting portion (103) are fixedly connected in sequence; A funnel cavity (105) is provided in the funnel portion (101), an expansion and fixing cavity (106) is provided in the fixing portion (102), and a through cavity (107) is provided in the connecting portion (103); the wide end of the funnel cavity (105) is in communication with the outside, the narrow end of the funnel cavity (105) is in communication with one end of the expansion and fixing cavity (106), and the other end of the expansion and fixing cavity (106) is in communication with one end of the through cavity (107); The maximum inner diameter of the expansion and fixing cavity (106) is greater than the inner diameter of the narrow end of the funnel cavity (105).

2. A venous filter according to claim 1, characterized in that: The expansion and fixing cavity (106) is a spherical cavity.

3. A venous filter according to claim 1, characterized in that: The other end of the through cavity (107) is in communication with the outside world.

4. A venous filter according to claim 1, characterized in that: A plurality of observation slits (104) are provided on the side wall of the fixing portion (102).

5. A venous filter according to claim 1, characterized in that: The filtering mechanism (2) is cage-shaped, and a recovery mechanism (1) is provided at each end of the filtering mechanism (2).

6. A recovery device according to claim 1-5, characterized in that: The recovery device (3) comprises a catheter (301), a balloon (302) is provided at the front of the catheter (301), and a connector (4) is provided at the rear end of the catheter (301); An injection cavity (303) is provided in the catheter (301), and a capsule cavity (304) is provided in the balloon (302). The front end of the injection cavity (303) is communicated with the capsule cavity (304), and the rear end of the injection cavity (303) is communicated with the connector (4); the connector (4) is connected to the injection end of an external syringe. The outer wall of the inflated balloon (302) abuts against the inner wall of the inflation and fixing cavity (106); It also includes a sheath tube (5), wherein the inner diameter of the sheath tube (5) is larger than the outer diameter of the wide-mouth end of the funnel cavity (105).

7. A recovery device according to claim 6, characterized in that: Both ends of the balloon (302) are provided with developing points.

8. A recovery device according to claim 6, characterized in that: A medium is provided in the capsule cavity (304), and the medium is a developer.

9. A venous filter set comprising a venous filter and a recovery device, wherein the venous filter and the recovery device are used in conjunction with each other, and wherein: The venous filter comprises a recovery mechanism (1) and a filtering mechanism (2), wherein the filtering mechanism (2) is composed of a plurality of filter arms, and the roots of the filter arms are fixedly connected to the bottom of the recovery mechanism (1); The recovery mechanism (1) comprises a funnel portion (101), a fixing portion (102), and a connecting portion (103), wherein the funnel portion (101), the fixing portion (102), and the connecting portion (103) are fixedly connected in sequence; A funnel cavity (105) is provided in the funnel portion (101), an expansion and fixing cavity (106) is provided in the fixing portion (102), and a through cavity (107) is provided in the connecting portion (103); the wide end of the funnel cavity (105) is in communication with the outside, the narrow end of the funnel cavity (105) is in communication with one end of the expansion and fixing cavity (106), and the other end of the expansion and fixing cavity (106) is in communication with one end of the through cavity (107); The maximum inner diameter of the expansion and fixing cavity (106) is greater than the inner diameter of the narrow end of the funnel cavity (105); The recovery device (3) comprises a catheter (301), a balloon (302) is provided at the front of the catheter (301), and a connector (4) is provided at the rear end of the catheter (301); An injection cavity (303) is provided in the catheter (301), and a capsule cavity (304) is provided in the balloon (302). The front end of the injection cavity (303) is communicated with the capsule cavity (304), and the rear end of the injection cavity (303) is communicated with the connector (4); the connector (4) is connected to the injection end of an external syringe. The outer wall of the inflated balloon (302) abuts against the inner wall of the inflation and fixing cavity (106); It also includes a sheath tube (5), wherein the inner diameter of the sheath tube (5) is larger than the outer diameter of the wide-mouth end of the funnel cavity (105).

Images