A thrombus suction catheter with a distal inner diameter that is variable

Abstract

This invention provides a thrombus aspiration catheter with a variable distal inner diameter, belonging to the field of interventional surgical instrument technology. The catheter includes an interventional catheter, an operating handle, and a collection component. The interventional catheter is used to move along the blood vessel to approach the thrombus location. The operating handle is located at the proximal end of the interventional catheter to provide suction force. The collection component is located at the distal end of the interventional catheter, with its proximal end communicating with the interventional catheter and its distal end open and adjustable in diameter. When the interventional catheter moves along the blood vessel to approach the thrombus, the diameter of the collection component is in a contracted state and not larger than the diameter of the interventional catheter. After the collection component reaches its position, it expands to increase its distal diameter for overall thrombus aspiration. This invention primarily addresses the technical problems of existing small-diameter thrombus aspiration catheters, which suffer from insufficient suction force, require repeated aspiration, and are prone to thrombus escape, while large-diameter catheters have poor permeability and are difficult to reach the lesion site.

Description

Technical Field

[0001] This invention belongs to the field of interventional surgical instruments technology, specifically relating to a thrombus aspiration catheter with a variable distal inner diameter. Background Technology

[0002] Acute ischemic stroke (AIS) is a common type of stroke. Currently, the main endovascular treatment is mechanical thrombectomy, which involves using a thrombectomy stent or a thrombectomy catheter to remove the thrombus. In the aspiration catheter thrombectomy, the embolus is directly aspirated into the catheter, which reduces the likelihood of small, escaped emboli compared to keeping the embolus within a stent. This reduces the risk of distal small vessel embolism and offers advantages such as relatively lower skill requirements for interventional physicians, simplified procedures (e.g., single-catheter systems), and a shorter learning curve, making it highly favored by medical professionals.

[0003] During aspiration, with a constant suction force, increasing the catheter diameter can significantly improve the suction force. Therefore, large-diameter aspiration catheters have emerged, offering advantages such as avoiding thrombus dragging, reducing the risk of fragmentation, improving first-time patency (FPE) rate, and reducing the need for salvage stent thrombectomy.

[0004] However, the diameter of blood vessels in the distal brain is very small (usually <2 mm), making it difficult for traditional large-diameter catheters (inner diameter > 0.060 inches) to reach the lesion site due to insufficient permeability. Clinically, this has forced the use of small-diameter catheters, which present the following problems: First, the suction force is insufficient, and the thrombus cannot be aspirated entirely; it can only be removed by aspiration of portions at a time, requiring repeated aspiration procedures (1-6 times). Second, during partial aspiration of the thrombus, fragmented thrombi can easily escape into the distal vessel, increasing the risk of distal embolism.

[0005] Therefore, there is a need to provide an improved technical solution that addresses the shortcomings of the existing technology. Summary of the Invention

[0006] The purpose of this invention is to provide a thrombus aspiration catheter with a variable distal inner diameter to solve the technical problems of insufficient suction force of small-diameter thrombus aspiration catheters, which require repeated aspiration and are prone to thrombus escape, while large-diameter catheters have poor permeability and are difficult to reach the lesion site.

[0007] To achieve the above objectives, the thrombus aspiration catheter with a variable distal inner diameter of the present invention provides the following technical solution:

[0008] A thrombus aspiration catheter with a variable distal inner diameter, comprising:

[0009] An interventional catheter used to move along a blood vessel to approach the location of a thrombus;

[0010] An operating handle, located at the proximal end of the interventional catheter, is used to provide suction force to the interventional catheter;

[0011] A collection component is disposed at the distal end of the interventional catheter, with the proximal end of the collection component communicating with the interventional catheter and the distal end being open and having an adjustable diameter;

[0012] As the interventional catheter moves along the blood vessel to approach the thrombus, the diameter of the collecting component is in a contracted state and is no larger than the diameter of the interventional catheter. After the collecting component is in place, it expands to increase the distal diameter for overall aspiration of the thrombus.

[0013] As a further optimized technical solution, the collection component includes a support frame, an expansion unit is provided at the far end of the support frame for adjusting the opening diameter at the far end of the support frame, and an elastic sealing membrane is arranged on the outer side of all support frames.

[0014] As a further optimized technical solution, the support frame includes multiple thrombectomy rods arranged at intervals along the circumference of the interventional catheter. One end of each thrombectomy rod is fixedly connected to the interventional catheter, and the other end extends away from the interventional catheter. The expansion unit is used to drive the distal ends of all thrombectomy rods to move away from or towards the axis.

[0015] As a further optimized technical solution, the expansion unit includes a deformable tube. One end of the deformable tube is arranged circumferentially around the distal end of the support frame to adjust the opening diameter of the distal end of the support frame, and the other end extends along the interventional catheter and is connected to the operating handle.

[0016] As a further optimized technical solution, the deformable tube is a polymer film tube. By injecting a filling medium into the deformable tube at the proximal end, the portion of the deformable tube arranged circumferentially around the distal end of the support frame is axially extended, thereby increasing the diameter of the distal end of the support frame.

[0017] As a further optimized technical solution, the proximal end of the operating handle has at least two branch channels, one branch channel for communicating with the lumen of the interventional catheter, and the other branch channel for communicating with the lumen of the deformable tube body.

[0018] As a further optimized technical solution, a protective layer is provided on the outside of the interventional catheter, and the protective layer has a guide channel for the extension of the deformable tube body.

[0019] As a further optimized technical solution, each of the thrombectomy rods is provided with a imaging point at its distal end.

[0020] As a further optimized technical solution, a stress diffusion tube is provided at the proximal end of the interventional catheter, and the operating handle is connected to the interventional catheter through the stress diffusion tube.

[0021] As a further optimized technical solution, a contrast ring is arranged at the distal end of the interventional catheter near the collection component.

[0022] Beneficial effects: This invention, by setting a variable-diameter collection component at the distal end of the interventional catheter, effectively solves the problem of traditional large-diameter catheters being unable to pass through narrow blood vessels in the distal brain during intervention, greatly improving the catheter's passage performance. Upon reaching the lesion site, the collection component can expand its distal diameter, significantly enhancing suction force compared to traditional small-diameter catheters, achieving efficient overall thrombus aspiration. This effectively solves the problem of repeated aspiration and low efficiency associated with small-diameter catheters. Furthermore, the collection component allows for complete thrombus aspiration, avoiding dragging of the thrombus and preventing the generation of small emboli during repeated splitting and aspiration, reducing the risk of thrombus escape during aspiration. This significantly improves thrombectomy efficiency and first-time recanalization rate, buying valuable time for patients with acute ischemic stroke.

[0023] Furthermore, the elastic sealing membrane arranged on the outside of the collecting component, together with the overall structural design, forms a tight thrombus protection system. This system can first achieve a sealed connection with the distal end of the interventional catheter, thereby ensuring the effective transmission of suction force. Then, it can also effectively prevent thrombi from escaping during the suction process, significantly reducing the risk of distal vascular embolism, greatly improving the surgical treatment effect, reducing the incidence of postoperative complications, and providing strong protection for the patient's recovery. It has extremely high clinical application value and promotion significance.

[0024] Furthermore, the contrast point at the distal end of the thrombectomy rod and the contrast ring at the distal end of the interventional catheter work together to provide the surgeon with precise positioning markers during the procedure. With the aid of imaging equipment, the surgeon can observe the position and status of the catheter and thrombus collection components in real time, clearly and accurately, enabling precise control of the surgical procedure. This effectively avoids surgical risks caused by misjudging the catheter's position, further improving the safety and accuracy of the procedure, reducing its complexity, and making the process smoother.

[0025] Furthermore, the unique branch channel design of the operating handle completely separates the suction force transmission channel from the deformable tube control channel, allowing doctors to more conveniently and accurately control the suction force and the expansion and contraction of the collection components during surgery. This makes the operation process clearer and more controllable, effectively reducing the possibility of operational errors. Meanwhile, the stress diffusion tube at the proximal end of the interventional catheter evenly distributes and transmits the suction force provided by the operating handle, significantly reducing local stress concentration in the catheter, enhancing the overall structural strength and stability of the catheter, and improving the sensitivity of the interventional catheter operation, providing reliable hardware support for the smooth progress of the surgery. Attached Figure Description

[0026] 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:

[0027] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the thrombus aspiration catheter with variable distal inner diameter of the present invention.

[0028] Figure 2 for Figure 1 A cross-sectional view along the AA direction;

[0029] Figure 3 This is a schematic diagram illustrating the working state of an embodiment of the thrombus aspiration guide with variable distal inner diameter of the present invention.

[0030] In the diagram: 100, interventional catheter; 110, protective layer; 111, guide channel; 120, guide layer; 130, support layer; 140, connecting layer; 200, operating handle; 210, branch channel; 300, collection component; 310, thrombectomy rod; 320, contrast point; 400, deformable tube; 500, stress diffusion tube; 600, contrast ring; 700, thrombus; 800, blood vessel. 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] This invention provides a thrombus aspiration catheter with a variable distal inner diameter, aiming to solve the technical problems of insufficient suction power of existing small-diameter catheters and poor passability of large-diameter catheters. The catheter includes an interventional catheter 100, an operating handle 200, and a thrombus collection component 300. The distal opening diameter of the collection component 300 (thrombus 700) is adjustable. During intervention, it contracts to facilitate passage through the blood vessel 800, and expands after reaching the target position to increase suction power for complete aspiration of the thrombus 700. The collection component 300 consists of a support frame with an expansion unit and an outer elastic sealing membrane, with diameter changes achieved through structures such as a deformable tube body 400. This invention improves catheter passability and suction power, prevents thrombus escape, reduces surgical risks, and increases thrombectomy efficiency and surgical safety, showing promising clinical application prospects.

[0036] Example 1

[0037] like Figure 1 As shown, the distally variable thrombus aspiration catheter includes an interventional catheter 100, an operating handle 200, and a collection component 300.

[0038] like Figure 1 , Figure 2 As shown, the interventional catheter 100 is mainly used to move along the blood vessel 800 to bring the distal collection component 300 closer and aspirate the thrombus 700. In this embodiment, the interventional catheter 100 is arranged from the outside to the inside as follows: a protective layer 110, a connecting layer 140, a support layer 130, and a guide layer 120. Among them, the guide layer 120 is made of polytetrafluoroethylene (PTFE), the support layer 130 is made of stainless steel wire or nickel-titanium wire, etc., through braiding or winding, the connecting layer 140 is made of polyether block amide (Pebax) tubes of different hardness spliced ​​and thermally bonded, and the protective layer 110 is a single layer of polymer material bonded to the connecting layer 140 through heat shrinking.

[0039] An operating handle 200 is located at the proximal end of the interventional catheter 100, and the proximal end of the operating handle 200 has at least two branch channels 210. One branch channel 210 is used to communicate with the lumen of the interventional catheter 100 to provide suction force to the interventional catheter 100.

[0040] The collecting component 300 is located at the distal end of the interventional catheter 100. The proximal end of the collecting component 300 is connected to the lumen of the interventional catheter 100, and the distal end is open and has an adjustable diameter.

[0041] During the intervention, the collecting component 300 is in a retracted state, with a diameter no larger than that of the interventional catheter 100. This design gives the catheter excellent passage performance. When facing narrow blood vessels 800, such as those in the distal brain, the catheter can easily pass through and smoothly approach the thrombus 700. Once the collecting component 300 reaches the target location, its distal diameter increases to maximize the contact area with the thrombus 700. At this point, under the action of suction, the thrombus 700 can be drawn in entirely. Compared to the traditional small-diameter catheter's staged aspiration method, this significantly improves thrombectomy efficiency and first-time patency rate.

[0042] In this embodiment, the collection component 300 includes a support frame that provides structural support for the collection component 300. An expansion unit is provided at the distal end of the support frame to adjust the opening diameter at the distal end. An elastic sealing membrane is arranged on the outer side of all support frames. The elastic sealing membrane ensures the transmission of suction force and also guarantees the sealing of the collection component 300, preventing the thrombus 700 from escaping. Furthermore, after being expanded, the elastic sealing membrane adheres better to the vessel wall 800, to a certain extent blocking distal blood flow and reducing distal blood flow impact, effectively reducing the incidence of thrombus 700 escape and thus reducing the risk of distal embolism.

[0043] Specifically, the support frame includes multiple thrombectomy rods 310 arranged circumferentially along the interventional catheter 100. The thrombectomy rods 310 are made of stainless steel or nickel-titanium metal tubing by laser cutting. The proximal end is bonded and fixed between the protective layer 110 and the connecting layer 140 of the interventional catheter 100 by a hot-melt process, and the distal end extends away from the interventional catheter 100. The expansion unit is used to drive the distal ends of all thrombectomy rods 310 to move away from or closer to the axis, thereby expanding or shrinking the distal diameter of the collection component 300.

[0044] In this embodiment, the expansion unit includes a deformable tube 400, which is a polymer film tube. The polymer film tube is lightweight and highly elastic. Deformation is achieved by injecting a filling medium into the lumen of the deformable tube 400, making the operation simple and highly controllable. One end of the deformable tube 400 is circumferentially arranged around the outer side of the distal end of the support frame and is fixedly connected to each contacting thrombectomy rod 310. The other end extends along the interventional catheter 100 and communicates with another branch channel 210 of the operating handle 200. By injecting a filling medium into the deformable tube 400 proximally, the portion circumferentially arranged around the distal end of the support frame elongates axially, thereby increasing the distance between adjacent thrombectomy rods 320, and thus increasing the distal diameter of the collection component 300.

[0045] Furthermore, the protective layer 110 of the interventional catheter 100 has a guide channel 111 for the extension of the deformable tube body 400. The protective layer 110 protects the interventional catheter 100 and the deformable tube body 400, and the guide channel 111 ensures that the extension path of the deformable tube body 400 on the interventional catheter 100 is stable and avoids displacement of the deformable tube body 400.

[0046] Furthermore, a stress diffusion tube 500 is provided at the proximal end of the interventional catheter 100. The stress diffusion tube 500 is composed of polymer materials such as polyolefin, and the operating handle 200 is connected to the interventional catheter 100 through the stress diffusion tube 500. The stress diffusion tube 500 can effectively transmit the stress applied by the operating handle 200, improving the efficiency of the interventional catheter 100 during the advancement process.

[0047] Furthermore, each thrombectomy rod 310 has a contrast point 320 at its distal end, and a contrast ring 600 is arranged at the distal end of the interventional catheter 100 near the collection component 300. Both the contrast ring 600 and the contrast point 320 are composed of radiopaque metals such as platinum-tungsten or platinum-iridium. The arrangement of the contrast ring 600 and the contrast point 320 provides precise positioning markers for the surgeon during the procedure. With the aid of imaging equipment, the surgeon can observe the position and status of the catheter and the thrombus collection component 300 in real time, clearly and accurately, achieving precise control over the surgical operation. This effectively avoids surgical risks caused by misjudging the catheter's position, further improving the safety and accuracy of the surgery, reducing the difficulty of the procedure, and making the surgical process smoother.

[0048] like Figure 3 As shown, during thrombus aspiration, the doctor first holds the operating handle 200 and moves the constricted collection component 300 along the interventional catheter 100 along the blood vessel 800 toward the thrombus 700. Since the diameter of the thrombus collection component 300 is no larger than the diameter of the interventional catheter 100 at this time, the catheter can smoothly pass through the narrowed blood vessel 800 to reach the lesion site.

[0049] When the distal end of the interventional catheter 100 approaches the thrombus 700, the physician injects a filling medium into the deformable tube 400 through one of the branch channels 210 at the proximal end of the operating handle 200. Because the deformable tube 400 is a polymer film tube, under the action of the filling medium, the portion circumferentially arranged around the distal end of the support frame elongates axially, thereby driving the distal end of the thrombus retrieval rod 310 to move away from the axis, increasing the distal diameter of the collecting component 300 and thus increasing the distal opening diameter. Simultaneously, the elastic sealing membrane arranged on the outside of the support frame also expands, ensuring the sealing of the collecting component 300.

[0050] Subsequently, the doctor applies suction force to the interventional catheter 100 through another branch channel 210 of the operating handle 200. The increased diameter of the collection component 300 generates stronger suction force, thereby drawing the thrombus 700 into the collection component 300 as a whole, and collecting the thrombus 700 into a specific container through the interventional catheter 100.

[0051] After the thrombus 700 is aspirated into the collecting component 300, the filling medium inside the deformable tube 400 can be extracted, causing the radial opening at the distal end of the collecting component 300 to narrow further, thereby ensuring that no small thrombi escape.

[0052] Throughout the procedure, the imaging point 320 at the distal end of the thrombectomy rod 310 and the imaging ring 600 at the distal end of the interventional catheter 100 help the surgeon clearly observe the position of the catheter and the thrombus collection component 300 under imaging equipment, ensuring the accuracy of the surgical operation. The protective layer 110 on the outside of the interventional catheter 100 and the guide channel 111 thereon protect the deformable tube body 400, ensuring its stable extension; the stress diffusion tube 500 at the proximal end of the interventional catheter 100 disperses the stress applied by the operating handle 200, preventing damage to the interventional catheter 100.

[0053] In summary, the thrombus aspiration catheter with a variable distal inner diameter provided by this invention solves the technical problems existing in current thrombus aspiration catheters through ingenious structural design, improves the efficiency, safety and success rate of thrombus aspiration surgery, reduces patient suffering, and has good application prospects.

[0054] It is understood that the above description is merely exemplary and the embodiments of this application do not limit the scope of the application.

[0055] 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 thrombus aspiration catheter with a distal inner diameter that is variable, characterized in that, include: An interventional catheter (100) is used to move along a blood vessel (800) to approach the location of a thrombus (700); An operating handle (200) is disposed at the proximal end of the interventional catheter (100) and is used to provide suction force to the interventional catheter (100); A collection component (300) is disposed at the distal end of the interventional catheter (100), the proximal end of the collection component (300) is connected to the interventional catheter (100), and the distal end is open and has an adjustable diameter; The collecting component (300) includes a support frame, an expansion unit is provided at the far end of the support frame for adjusting the opening diameter at the far end of the support frame, and an elastic sealing membrane is arranged on the outside of all support frames. The expansion unit includes a deformable tube (400), one end of which is arranged circumferentially around the distal end of the support frame to adjust the opening diameter of the distal end of the support frame, and the other end extends along the interventional catheter (100) and is connected to the operating handle (200). The deformable tube (400) is a polymer film tube. By injecting a filling medium into the lumen of the deformable tube (400), the portion of the deformable tube (400) arranged circumferentially around the distal end of the support frame is axially extended to increase the diameter of the distal end of the support frame. When the interventional catheter (100) moves along the blood vessel (800) to approach the thrombus (700), the diameter of the collecting component (300) is in a contracted state and is not larger than the diameter of the interventional catheter (100). After the collecting component (300) is in place, the collecting component (300) expands to increase the distal diameter for overall aspiration of the thrombus (700). After the thrombus (700) is aspirated into the collecting component (300), the distal opening of the collecting component (300) is radially reduced by the expansion unit to prevent small emboli from escaping.

2. The thrombus aspiration catheter of claim 1, wherein, The support frame includes a plurality of thrombectomy rods (310) arranged circumferentially along the interventional catheter (100). One end of each thrombectomy rod (310) is fixedly connected to the interventional catheter (100), and the other end extends away from the interventional catheter (100). The expansion unit is used to drive the distal ends of all thrombectomy rods (310) to move away from or closer to the axis.

3. The thrombus aspiration catheter of claim 1, wherein, The operating handle (200) has at least two branch channels (210) at its proximal end, one branch channel (210) for communicating with the lumen of the interventional catheter (100) and the other branch channel (210) for communicating with the lumen of the deformable tube body (400).

4. The thrombus aspiration catheter of claim 1, wherein, The interventional catheter (100) is provided with a protective layer (110) on its outer side, and the protective layer (110) has a guide channel (111) for the extension of the deformable tube body (400).

5. The thrombus aspiration catheter of claim 2, wherein, Each of the thrombectomy rods (310) has a imaging point (320) at its distal end.

6. The thrombus aspiration catheter of any of claims 1-5, wherein, The interventional catheter (100) is provided with a stress diffusion tube (500) at its proximal end, and the operating handle (200) is connected to the interventional catheter (100) through the stress diffusion tube (500).

7. The thrombus aspiration catheter of any of claims 1-5, wherein the distal inner diameter is variable by a distance of at least 0.5 mm. The distal end of the interventional catheter (100) is provided with a contrast ring (600) near the collection component (300).

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