A thrombectomy assist device

Abstract

The application provides a thrombus extraction auxiliary device, and belongs to the technical field of interventional operation medical instruments. The thrombus extraction auxiliary device comprises a delivery microcatheter, a thrombus collection filter screen and a support and interception component. The thrombus collection filter screen can be automatically expanded and is used for being delivered to the distal end of a lesion narrow position along the delivery microcatheter. The support and interception component is arranged in the thrombus collection filter screen. When the support and interception component is radially expanded, the distal end blood flow can be intercepted, and the thrombus collection filter screen can be supported to be close to the inner wall of a blood vessel, so that the thrombus collection filter screen fully intercepts thrombus. The technical problem that the existing technology has the edge leakage risk of the distal end filter screen and the difficulty in completely removing the thrombus by the closed balloon is mainly solved.

Description

Technical Field

[0001] This invention belongs to the field of endovascular interventional medical device technology, specifically relating to a thrombectomy auxiliary device. Background Technology

[0002] Thrombectomy assist devices are instruments used in endovascular treatment (EVT) of acute ischemic stroke (AIS) to improve thrombectomy efficiency, reduce complications, or optimize the surgical procedure. They are typically used in conjunction with mechanical thrombectomy devices (such as stent thrombectomy devices and aspiration catheters) to enhance thrombus removal or reduce the risk of distal embolism. Specifically, they intercept thrombus fragments that may detach during thrombectomy, preventing them from flowing to distal vessels and causing secondary embolism. The working principle of thrombectomy assist devices is primarily to be placed in the vessel distal to the thrombus before or during the thrombectomy procedure to intercept thrombus fragments that may detach during the thrombectomy process and flow distally with the bloodstream, thus preventing distal vessel embolism.

[0003] There are two main types of thrombectomy aids: distal filters and closed balloons.

[0004] The distal filter works by delivering a compressed filter to the distal end of the embolism site via a guidewire, then releasing and unfolding the filter. The filter's mesh is designed to allow blood flow while intercepting emboli. Normal surgical procedures are then performed to treat the embolism. During the procedure, small emboli may flow with the blood to the distal end and enter the filter. After the surgery, the distal filter is retracted and removed from the body.

[0005] The occlusion balloon involves inflating a balloon in the normal segment of the internal carotid artery distal to the stenosis, temporarily blocking the normal blood flow in the common carotid artery (CCA). The procedure is performed under no-flow conditions. Any detached embolus is blocked proximally by the balloon. After the procedure, the blood containing the embolus is aspirated through an aspiration catheter, and then the balloon occlusion is released.

[0006] However, the aforementioned embolism protection device has the following problems:

[0007] Distal filters are generally made of metal. After they expand inside the blood vessel, the rigidity of the metal itself cannot completely fit the blood vessel wall, causing emboli to leak from the edge of the filter.

[0008] While closed balloons offer better adhesion to the balloon wall, subsequent aspiration may not be able to completely remove all dislodged emboli.

[0009] Therefore, there is a need to provide an improved technical solution that addresses the shortcomings of the existing technology. Summary of the Invention

[0010] The purpose of this invention is to provide an embolus removal auxiliary device to solve the technical problems in the prior art where there is a risk of edge leakage in the distal filter and the sealing balloon cannot completely remove the embolus.

[0011] To achieve the above objectives, the thrombectomy auxiliary device of the present invention provides the following technical solution:

[0012] A thrombectomy aid device, comprising:

[0013] Delivery of microcatheters;

[0014] An embolus collection filter, which can expand automatically, is used to be delivered with the delivery microcatheter to the distal end of the lesion stenosis;

[0015] A support and flow-blocking component is disposed inside the embolus collection filter. When it expands radially, it can block distal blood flow and support the embolus collection filter to adhere tightly to the inner wall of the blood vessel, so that the embolus collection filter can effectively intercept emboli.

[0016] As a further optimized technical solution, the plug collection filter screen includes a conveying guide wire and a filter screen body. The filter screen body has a constriction structure coaxially arranged at its proximal end, and the filter screen body is fixedly connected to the distal end of the conveying guide wire through the constriction structure.

[0017] As a further optimized technical solution, the supporting interception component includes an umbrella-shaped interception section, which includes a radially expandable support and a membrane disposed on the support. The opening of the umbrella-shaped interception section after expansion faces the same direction as the opening of the plug collection filter.

[0018] As a further optimized technical solution, the supporting intercepting component also includes a contraction section for the umbrella-shaped intercepting section in the contracted and unfolded state.

[0019] As a further optimized technical solution, the shrinking part includes a sliding block, a pulling wire, and a traction component. The sliding block is slidably disposed on the conveying guide wire. Multiple pulling wires are provided. One end of each pulling wire is fixedly connected to the sliding block, and the other end is fixedly connected to the umbrella-shaped intercepting part. The traction component is used to pull the sliding block to slide along the conveying guide wire.

[0020] As a further optimized technical solution, the traction component is a traction wire, one end of which is fixedly connected to the sliding block, and the other end extends along the delivery microcatheter to the proximal end.

[0021] As a further optimized technical solution, the proximal end of the drawing wire passes through the contraction structure and is fixedly connected to the sliding block.

[0022] As a further optimized technical solution, the proximal end of the drawing wire passes through the contraction structure and is fixedly connected to the sliding block.

[0023] As a further optimized technical solution, the shrinkage structure includes a tension wire and a connecting block, with one end of the tension wire fixedly connected to the filter body and the other end fixedly connected to the connecting block.

[0024] As a further optimized technical solution, the connecting block has a through hole arranged along the axial direction, and the proximal end of the drawing wire passes through the through hole and is fixedly connected to the sliding block.

[0025] Beneficial Effects: Compared to traditional distal embolus collection filters, the embolus collection auxiliary device of this invention further supports the embolus collection filter through the radial expansion of the supporting interception component. This increases the adhesion between the embolus collection filter and the vessel wall, allowing the filter to overcome its own rigidity and fit the vessel wall more closely, effectively avoiding edge leakage. Regarding the embolus residue problem present in traditional closed balloon emboli, this device reduces blood flow velocity after the supporting interception component blocks distal blood flow, facilitating efficient interception and collection of emboli in a relatively stable blood flow environment. Emboli initially accumulate near the proximal end of the supporting interception component. After the procedure, the supporting interception component is retracted, and the fully supported embolus collection filter can effectively collect the emboli, eliminating the need for complex and difficult-to-complete aspiration procedures. This simplifies the surgical procedure, reduces surgical steps, shortens surgical time, and lowers surgical risks and patient anesthesia time.

[0026] In summary, this invention utilizes the combined action of the embolus collection filter and the supporting and intercepting component. On the one hand, the supporting and intercepting component further supports the embolus collection filter, allowing it to fit more closely to the inner wall of the blood vessel, effectively solving the problem of leakage at the edge of traditional distal filters. On the other hand, the supporting and intercepting component can effectively intercept distal blood flow, weakening the flushing effect of blood flow on emboli, and also making it easier for emboli to be captured by the embolus collection filter. Attached Figure Description

[0027] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Wherein:

[0028] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the thrombectomy auxiliary device of the present invention;

[0029] Figure 2 This is an exploded view of the thrombus collection filter and the support and interception component in one embodiment of the thrombus removal auxiliary device of the present invention.

[0030] In the diagram: 100, delivery microcatheter; 200, plug collection filter; 210, delivery guide wire; 220, filter body; 230, contraction structure; 231, tension wire; 232, connecting block; 233, perforation; 310, support and interception component; 311, umbrella-shaped interception section; 3111, bracket; 3112, membrane; 312, contraction section; 3121, sliding block; 3122, pull wire; 3123, traction line. Detailed Implementation

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0032] In the description of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., 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 the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected" and "linked" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; they can refer to a direct connection or an indirect connection through intermediate components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances. Furthermore, the term "proximal end" uniformly refers to the end closer to the operator, while "distal end" refers to the end farther from the operator.

[0033] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0034] The shapes and sizes of the components in the accompanying drawings do not reflect the actual proportions of the product; they are only intended to illustrate the content of the invention.

[0035] In neurointerventional surgery, traditional thrombectomy aids have drawbacks. The distal embolus-collecting filter cannot fully conform to the vessel wall, leading to embolus leakage at the edges. Furthermore, the occlusion balloon is insufficient to completely remove dislodged emboli. To address these technical problems, this invention provides a thrombectomy aid. The core components of this device include a delivery microcatheter 100, an embolus-collecting filter 200, and a support and closure component 310. The delivery microcatheter 100 is used to deliver the automatically expanding embolus-collecting filter 200 along the intracranial vascular pathway to the distal end of the stenotic lesion. The embolus-collecting filter 200 consists of a delivery guidewire 210, a filter body 220, and a contraction structure 230. The support and closure component 310 is located inside the embolus-collecting filter 200 and has a dual function. When it expands radially, it can further support the embolus collection filter 200, allowing it to fit more closely to the inner wall of the blood vessel, effectively solving the problem of edge leakage of traditional distal filters 200. On the other hand, it can effectively temporarily block distal blood flow, weakening the flushing effect of blood flow on emboli, making it easier for emboli to be captured by the embolus collection filter 200. The supporting and blocking component 310 consists of an umbrella-shaped blocking part 311 composed of a shape memory alloy stent 3111 and a membrane 3112, and a contraction part 312 composed of a sliding block 3121, a pull wire 3122, and a traction wire 3123. After the shape memory alloy stent is deployed, it forms a stable blocking space and provides support, and the contraction part 312 facilitates postoperative retrieval.

[0036] Through the coordinated operation of the above-mentioned components, the thrombectomy auxiliary device of the present invention significantly improves the thrombus interception efficiency and shortens the operation time, providing a safer and more reliable guarantee for neurointerventional surgery, and has important value in clinical application.

[0037] Example 1

[0038] like Figure 1 , Figure 2 As shown, the thrombectomy auxiliary device includes a delivery microcatheter 100, a thrombus collection filter 200, and a support and interception component 310.

[0039] The delivery microcatheter 100 has good flexibility and pushability, and can be adapted to complex intracranial vascular pathways. It can deliver the compressed embolus collection filter 200 to the distal end of the lesion stenosis.

[0040] The embolus collection filter 200 can expand automatically and is used to deliver the embolus to the distal end of the stenotic lesion via the delivery microcatheter 100.

[0041] Specifically, the embolus collecting filter 200 consists of a guide wire 210, a filter body 220, and a contraction structure 230. The contraction structure 230 is located at the proximal end of the filter body 220 and is coaxially arranged with it. The filter body 220 is fixedly connected to the distal end of the guide wire 210 through the contraction structure 230. The filter body 220 is integrally woven from a nickel-titanium alloy, forming a rhomboid pore structure, which ensures good permeability while providing excellent embolus interception capability. After expansion, the filter body 220 has a constant-diameter section at the proximal end and a constricted-diameter section at the distal end. The constant-diameter section has a nearly constant diameter and is cylindrical in shape, with its opening facing the proximal end. The diameter of the constricted-diameter section gradually decreases from the proximal end to the distal end. The purpose of this design is that, due to the diverse morphologies of intracranial blood vessels, including tortuosity, dilation, and stenosis, the constant-diameter section of the filter body 220 can better adapt to the relatively regular parts of the blood vessels. Its near-constant diameter allows for a close fit to the inner wall of the vessel, reducing gaps caused by shape differences and lowering the risk of emboli leaking from the edges. The gradually tapering design of the tapering section better adapts to the gradually narrowing or irregular distal parts of the blood vessel, allowing the entire filter 220 to better conform to the natural shape of the blood vessel. This enhances the adaptability of the filter 220 in different vascular environments, ensuring good interception effects even under complex vascular conditions. Furthermore, the constant-diameter section provides a stable blood flow channel, ensuring normal blood flow within the filter and maintaining relative stability of intravascular hemodynamics. This reduces the probability of complications such as vasospasm and thrombosis caused by excessive interference with blood flow due to the filter structure. The gradually tapering design of the tapering section makes the change in blood flow velocity within the filter smoother, further reducing stimulation to the vessel wall, helping to protect the integrity of vascular endothelial cells, and promoting postoperative recovery for patients.

[0042] The retractable structure 230 facilitates rapid retrieval of the filter after surgery, improving the convenience and safety of the surgical procedure. Specifically, the retractable structure 230 includes tension wires 231 and connecting blocks 232. Multiple tension wires 231 are arranged, with their ends fixedly connected to the proximal end of the filter body 220 and the connecting block 232, respectively. The connecting block 232 is fixedly located at the distal end of the delivery guide wire 210. The purpose of this design is that when the surgical procedure is completed and the filter body 220 is retrieved, all the tension wires 231, forming a tapered structure, can act as a guide structure, making it easier for the filter body 220 to retract into the delivery microcatheter 100 for convenient retrieval.

[0043] The support and interception component 310 is disposed inside the embolus collection filter 200. When it expands radially, it can intercept distal blood flow and support the embolus collection filter 200 to adhere tightly to the inner wall of the blood vessel, so that the embolus collection filter 200 can fully intercept emboli.

[0044] In this embodiment, the supporting intercepting component 310 includes an umbrella-shaped intercepting portion 311 and a contracting portion 312.

[0045] The umbrella-shaped interception section 311 includes a support 3111 and a membrane 3112. The support 3111 is made of a shape-memory alloy and is fixedly connected to the distal end of the filter body 220. It can automatically expand radially into an umbrella-shaped structure. The membrane 3112 is disposed on the inner and / or outer side of the support 3111. The opening of the umbrella-shaped interception section 311 after expansion faces the same direction as the opening of the embolus collecting filter 200. The opening end of the umbrella-shaped interception section 311 is flush with the opening end of the filter body 220 or is a predetermined distance closer to the distal end than the opening end of the filter body 220. In this way, the umbrella-shaped interception section 311 can fully support the filter body 220, making the opening end of the filter body 220 larger. This makes the opening of the filter body 220 present a funnel shape with a larger proximal diameter, thereby making the filter body 220 fit the inner wall of the blood vessel more closely and facilitating the effective interception of emboli. In addition, due to its special shape, the umbrella-shaped interception component 311 can collect part of the embolus while intercepting it. In this way, when the umbrella-shaped interception component 311 is retracted, some of the embolus has already been collected inside, and only the uncollected part will enter the embolus collection filter 200. The number of embolus in the embolus collection filter 200 is less than that in the existing cases where all of them are collected directly, thus making it easier to ensure unobstructed blood flow and minimizing the impact on the patient.

[0046] The contraction section 312 is used to contract the umbrella-shaped flow-blocking section 311 in its expanded state. Specifically, the contraction section 312 includes a sliding block 3121, a pulling wire 3122, and a traction line 3123. The sliding block 3121 is slidably disposed on the delivery guide wire 210. Multiple pulling wires 3122 are provided, each with one end fixedly connected to the sliding block 3121 and the other end fixedly connected to the umbrella-shaped flow-blocking section 311. One end of the traction line 3123 is fixedly connected to the sliding block 3121, and the other end extends along the delivery microcatheter 100 to the proximal end. In this embodiment, the end of the pulling wire 3122 near the umbrella-shaped flow-blocking section 311 is fixedly connected to the proximal end of the support 3111.

[0047] Furthermore, the connecting block 232 has a perforation 233 arranged axially, and the proximal end of the pulling wire 3122 passes through the perforation 233 of the contraction structure 230 and is fixedly connected to the sliding block 3121. The pulling wire 3122 can slide along the perforation 233, which ensures the coaxiality of the supporting interception component 310 and the plug collecting filter 200, enhances the structural stability of the entire device, and during device assembly and surgical operation, the pulling wire 3122 can only pass through the contraction structure 230 along the axial direction of the perforation 233, which limits the position of the supporting interception component 310 within the plug collecting filter 200. When the proximal end of the pulling wire 3122 is fixedly connected to the sliding block 3121, it can be ensured that the supporting interception component 310 is always on the central axis of the plug collecting filter 200, avoiding the offset of the supporting interception component 310 due to improper installation or operation, thereby ensuring the high coaxiality of the two in spatial position.

[0048] During the procedure, the doctor first selects an appropriate intracranial embolization protection device based on the patient's angiography images. Then, a puncture is performed at the vascular puncture site, and a guidewire (a commonly used device in existing technology) is slowly inserted into the blood vessel through the puncture site. Next, a delivery sheath (also a commonly used device in existing technology) is used to reach the target location along the path guided by the guidewire, establishing a path for delivering the treatment device to the target location. The guidewire is then withdrawn, and the delivery microcatheter 100 is slowly pushed along the delivery path established by the delivery sheath. After confirming the accurate positioning of the delivery microcatheter 100, the embolus collection filter 200 and the supporting interception component 310 are pushed together through the delivery microcatheter 100 to the distal end of the lesion stenosis. When the embolus collection filter 200 and the supporting interception component 310 reach the predetermined position, they automatically expand and unfold, and the filter body 220 quickly forms a stable interception structure under the support of the supporting interception component 310. It should be noted that this device is suitable for treatment sites with compensating blood vessels at the distal end. Although the distal blood flow will be temporarily blocked when the supporting obstruction component 310 expands, the compensating blood vessel will not cause the temporary obstruction to affect the patient. Moreover, the supporting obstruction component 310 will be retracted in time after the subsequent surgical operation is completed to restore the overall blood flow in the blood vessel.

[0049] Subsequently, during the plaque treatment procedure, the embolus collection filter 200 and the support interception component 310 work together to reduce blood flow velocity and effectively intercept thrombi and plaque fragments that detach during the procedure. After the procedure, the traction wire 3123 is pulled proximally, causing the sliding block 3121 to move proximally. The umbrella-shaped interception section 311 is gradually contracted by the traction wire 3122, initially collecting some emboli. Emboli that escape during the retraction of the umbrella-shaped interception section 311 will enter the filter body 220. Then, the filter body 220 is contracted to complete the contraction of the embolus collection filter 200. After the umbrella-shaped interception section 311 is fully contracted, the entire device is safely removed from the blood vessel using the contraction structure 230.

[0050] In summary, the thrombectomy auxiliary device provided by this invention, through its innovative structural design, effectively solves the problems in the prior art, improves the interception and removal of thrombi in neurointerventional surgery, and has good clinical application prospects and promotion value.

[0051] It is understood that the above description is merely exemplary and the embodiments of this application do not limit the scope of the application.

[0052] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention shall be within the scope of protection of the pending claims of the present invention.

Claims

1. A thrombectomy auxiliary device, characterized in that, include: Delivery microcatheter (100); Embolism collection filter (200), which can expand automatically and is used to be delivered with the delivery microcatheter (100) to the distal end of the lesion stenosis; A support interception component (310) is provided inside the embolus collection filter (200). When it expands radially, it can intercept distal blood flow and support the embolus collection filter (200) to adhere tightly to the inner wall of the blood vessel so that the embolus collection filter (200) can fully intercept emboli. The plug collection filter (200) includes a conveying guide wire (210) and a filter body (220). The filter body (220) has a constriction structure (230) coaxially arranged at its proximal end. The filter body (220) is fixedly connected to the distal end of the conveying guide wire (210) through the constriction structure (230). The supporting intercepting component (310) includes an umbrella-shaped intercepting part (311), which includes a radially expandable support (3111) and a membrane (3112) disposed on the support (3111). The opening of the umbrella-shaped intercepting part (311) after being expanded has the same orientation as the opening of the plug collecting filter (200). The supporting intercepting component (310) also includes a contraction part (312) for the umbrella-shaped intercepting part (311) in the contracted and unfolded state. The contraction section (312) includes a sliding block (3121), a pulling wire (3122), and a traction component (3123). The sliding block (3121) is slidably disposed on the conveying guide wire (210). There are multiple pulling wires (3122). One end of each pulling wire (3122) is fixedly connected to the sliding block (3121), and the other end is fixedly connected to the umbrella-shaped intercepting section (311). The traction component (3123) is used to pull the sliding block (3121) to slide along the conveying guide wire (210).

2. The thrombectomy auxiliary device according to claim 1, characterized in that, The traction component (3123) is a traction wire. One end of the traction wire is fixedly connected to the sliding block (3121), and the other end extends along the delivery microcatheter (100) to the proximal end.

3. The thrombectomy auxiliary device according to claim 1, characterized in that, The end of the drawing wire (3122) near the umbrella-shaped cutoff section (311) is fixedly connected to the proximal end of the bracket (3111).

4. The thrombectomy auxiliary device according to claim 1, characterized in that, The proximal end of the drawing wire (3122) passes through the contraction structure (230) and is fixedly connected to the sliding block (3121).

5. The thrombectomy auxiliary device according to claim 4, characterized in that, The shrinking structure (230) includes a tension wire (231) and a connecting block (232). One end of the tension wire (231) is fixedly connected to the filter body (220), and the other end is fixedly connected to the connecting block (232).

6. The thrombectomy auxiliary device according to claim 5, characterized in that, The connecting block (232) has a through hole (233) arranged along the axial direction, and the proximal end of the drawing wire (3122) passes through the through hole (233) and is fixedly connected to the sliding block (3121).

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