A novel thrombus aspiration catheter

Abstract

This invention relates to a novel thrombus aspiration catheter, comprising: a shell with an aspiration connector; an inner tube assembly including an inner tube, a portion of which is located within the shell and another portion outside the shell; and a rotary cutting assembly including a middle tube fitted onto the inner tube, a flexible rotary cutting head located outside the shell, a rotation drive unit, an outer tube, and a movement drive unit. The flexible rotary cutting head includes multiple flexible tips, connected to the distal end of the middle tube, and the rotation drive unit is connected to the proximal end of the middle tube, for driving the flexible rotary cutting head to rotate and cut around the axis of the inner tube; the outer tube is fitted onto the middle tube, and its proximal end is sealed to the middle tube; the proximal end of the outer tube is connected to the movement drive unit, which is configured to drive the outer tube to move back and forth; the flexible tip has multiple barbs arranged at a predetermined angle to its axial direction. This invention has the functions of thrombus aspiration, thrombus cutting, thrombus entanglement, and free thrombus blocking.

Description

Technical Field

[0001] The invention relates to the field of medical device technology, and in particular to a novel thrombus aspiration catheter. Background Technology

[0002] A thrombus is a potentially fatal blood clot that forms in an artery (arterial thrombosis) or vein (venous thrombosis). Once formed, a thrombus can obstruct or block normal blood flow and may even break off and travel through the bloodstream to an organ, blocking its blood supply with very serious consequences. The danger of thromboembolism lies in its ability to cause localized blockage, leading to organ ischemia, hypoxia, and failure. Thrombosis can also trigger serious cardiovascular events such as acute myocardial infarction, pulmonary embolism, cerebral infarction, lower extremity gangrene, and kidney failure, posing a severe threat to a patient's life and health. Currently, with the continuous development of endovascular treatments, especially the advent of various volume reduction techniques, the success rate of removing complex endovascular thrombi has been significantly improved.

[0003] In actual surgical procedures, thrombectomy catheters are increasingly being used as a form of mechanical thrombectomy (PMT) and have become an important clinical tool. Currently available thrombectomy catheters employ various methods, including simple aspiration thrombectomy, aspiration combined with stent thrombectomy, rheological aspiration thrombectomy, and rotary thrombectomy. Simple aspiration thrombectomy is primarily used for fresh thrombi, but it cannot handle old thrombi. Larger thrombi can also easily block the aspiration catheter, affecting the aspiration effect. Aspiration combined with stent thrombectomy is more widely used for neurovascular thrombectomy, but its effectiveness in handling old thrombi and eccentric thrombi is not ideal. Rheological thrombectomy is mainly used for the aspiration of fresh peripheral thrombi, but it easily damages red blood cells, leading to hemoglobinuria and kidney damage. Finally, rotary thrombectomy uses rotary cutting to break up the thrombus and aspirate it out of the body. During the cutting process, thrombi may migrate to distal sites, causing secondary damage, and it cannot handle thrombi that are adhered to the wall. Therefore, in response to the current needs of thrombus aspiration treatment technology, there is an urgent need to develop a safe, efficient, widely applicable, and easy-to-operate instrument for the aspiration and removal of intracavitary thrombi.

[0004] Patent document CN115337078A discloses a thrombus removal device, which includes a transmission catheter, a thrombectomy stent, and an aspiration catheter. The transmission catheter passes through the thrombectomy stent and the aspiration catheter. The distal end of the transmission catheter mates with the distal end of the thrombectomy stent. The proximal end of the thrombectomy stent contacts the distal end of the aspiration catheter. The thrombectomy stent is a compressible and expandable stent structure, including six torsional cutting arms. The thrombectomy stent provided by this invention has a simple structure and can remove thrombi by rotation after compression and expansion, thus improving the efficiency of thrombus removal. This invention patent utilizes the compression and expansion of the stent to remove thrombi. This invention has limitations, especially for old thrombi, where simple compression and expansion of the stent cannot cut them completely, thus affecting the aspiration effect.

[0005] The patent document CN115444506A discloses an aspiration catheter provided by this invention, comprising: a tubing, a mandrel, an end, and a thrombectomy component; the end is connected to one end of the mandrel, and the thrombectomy component is connected to either the mandrel or the end; the tubing has a lumen and a side opening communicating with the lumen; the mandrel, end, and thrombectomy component are inserted into the lumen, and the aspiration catheter has a first usage state and a second usage state; in the first usage state, the end seals the opening of the lumen, and the side opening is positioned opposite the thrombectomy component; in the second usage state, the end separates from the tubing, so that an end opening is formed between the end of the end and the end of the tubing, and the end opening communicates with the lumen, thus the aspiration catheter has both side opening aspiration and catheter shaft end aspiration functions. This patent utilizes a side hole and the distal catheter shaft for aspiration, and a thrombectomy component for thrombus fragmentation. Because the thrombectomy component has a cutting edge, it cannot remove thrombi on the vessel wall. Furthermore, thrombus fragmentation by bending the vessel or moving it off-center may damage the vessel wall, posing a safety hazard and limiting its application.

[0006] Therefore, the existing technology has the following problems:

[0007] 1. When dealing with old blood clots, it may be impossible to cut them completely or at all; this may cause the blood clot to become free, resulting in the risk of secondary damage.

[0008] 2. Larger thrombi can easily block the aspiration catheter, affecting the aspiration effect;

[0009] 3. Thrombi that are attached to the vessel wall or located in tortuous blood vessels cannot be treated. Summary of the Invention

[0010] Therefore, the technical problem that the invention aims to solve is to overcome the aforementioned problems in the prior art.

[0011] To solve the above-mentioned technical problems, a novel thrombus aspiration catheter is provided, comprising:

[0012] The outer casing is equipped with a suction connector;

[0013] An inner tube assembly, comprising an inner tube, a portion of which is located within a housing and another portion of which is located outside the housing;

[0014] A rotary cutting assembly includes a middle tube fitted onto an inner tube, a flexible rotary cutting head located outside the outer shell, a rotary drive unit, an outer tube, and a moving drive unit. The flexible rotary cutting head includes multiple flexible heads, which are connected to the distal end of the middle tube. The rotary drive unit is connected to the proximal end of the middle tube and is used to drive the flexible rotary cutting head to rotate and cut around the axis of the inner tube. The outer tube is fitted onto the middle tube, and the proximal end of the outer tube is sealed to the middle tube. The proximal end of the outer tube is connected to the moving drive unit, which is configured to drive the outer tube to move back and forth, for retracting or exposing the flexible rotary cutting head when it is fitted outside the flexible rotary cutting head. The flexible head has multiple barbs arranged at a predetermined angle to the flexible head along its axial direction.

[0015] In one embodiment of the invention, the flexible rotary cutting head is elastic.

[0016] In one embodiment of the invention, the axes of the plurality of flexible heads are set at a predetermined angle to the axis of the middle layer tube.

[0017] In one embodiment of the invention, multiple flexible heads are arranged in a spiral around the axis of the middle layer tube.

[0018] In one embodiment of the invention, multiple flexible heads are arranged in multiple rows along the axial direction of the middle layer tube, and one row of flexible heads is arranged in a circle along the axial direction.

[0019] In one embodiment of the invention, the flexible rotary cutting head is spherical or umbrella-shaped.

[0020] In one embodiment of the invention, the lengths of the multiple flexible heads differ.

[0021] In one embodiment of the invention, the free end of the flexible head has a rounded corner portion.

[0022] In one embodiment of the invention, multiple rows of barbs are arranged along the axis of the flexible head, and each row of barbs has at least one barb.

[0023] In one embodiment of the invention, multiple barbs are spirally arranged around the axis of the flexible head multiple times.

[0024] In one embodiment of the invention, the inner tube assembly further includes a flexible tip connected to the distal end of the inner tube; the flexible tip has a step at the end near the outer tube, the minor and major diameters of the step matching the inner and outer diameters of the outer tube.

[0025] In one embodiment of the invention, the rotary drive unit includes a manual drive member, an electric drive member, and a switching member for switching between the manual drive member and the electric drive member.

[0026] In one embodiment of the invention, the manual drive includes a handwheel fixedly connected to the middle tube, with the outer ring of the handwheel protruding outside the housing.

[0027] In one embodiment of the invention, the electric drive unit includes a power unit, a drive gear, and a driven gear; the output end of the power unit is connected to the drive gear, the drive gear meshes with the driven gear, and the driven gear is coaxially connected to the middle layer tube.

[0028] In one embodiment of the invention, the switching element includes a limit switch, a limit member, a limit button, a limit pin, and an elastic member;

[0029] The top of the limit switch protrudes outside the housing, the middle part forms a sliding pair with the housing, and the bottom end is connected to the limit component. The bottom of the limit component has a slot, and the electric drive component is located in the slot. The limit button is slidably connected to the limit switch. The bottom end of the limit button has a limit pin whose axis is perpendicular to both the sliding direction of the limit button and the axis of the middle tube. The elastic element is connected to the bottom end of the limit pin and is used to drive the limit pin to reset. The inner wall of the housing has limit grooves at both ends of the limit switch's travel stroke that cooperate with the limit pin.

[0030] In one embodiment of the invention, the moving drive unit includes a thumb drive and a connecting tube connected to the thumb drive. The top end of the thumb drive protrudes from the outer casing and moves back and forth along the axial direction of the outer tube with the outer casing. The bottom end of the thumb drive is fixedly connected to the outer tube.

[0031] The above-mentioned technical solution of the invention has the following advantages compared with the prior art:

[0032] The novel thrombus aspiration catheter of this invention features a flexible cutting component at its distal end. This component allows for simultaneous thrombus aspiration and cutting of the thrombus, facilitating aspiration and reducing blockage during the process. Furthermore, the flexible cutting tip has barbs that allow for the wrapping of old thrombi around the tip, introducing them into the outer tube for subsequent aspiration. The flexible cutting tip of this application comprises multiple flexible components, exhibiting excellent flexibility and superior adherence to vessel walls. When removing thrombi adhering to vessel walls or from narrow or tortuous blood vessels, the flexible cutting tip can cut or wrap the thrombus, resulting in more efficient and thorough thrombus removal without damaging the vessel wall. It also effectively blocks the cut thrombus, preventing it from migrating to other sites and causing secondary damage. In summary, this thrombus aspiration catheter simultaneously performs thrombus aspiration, thrombus cutting, thrombus wrapping, and free thrombus blocking functions, offering advantages such as ease of use, safety, effectiveness, and multifunctionality. Attached Figure Description

[0033] To make the invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0034] Figure 1 This is a three-dimensional schematic diagram of a novel thrombus aspiration catheter according to a preferred embodiment of the present invention;

[0035] Figure 2 yes Figure 1 The diagram shows the internal structure of a novel thrombus aspiration catheter.

[0036] Figure 3 yes Figure 1 The diagram shows a structural schematic of a flexible rotary cutting component in a novel thrombus aspiration catheter.

[0037] Figure 4 yes Figure 3 A schematic diagram of an alternative structure for a medium-flexible rotary cutting component;

[0038] Figure 5 yes Figure 4 The main view;

[0039] Figure 6 yes Figure 3 A schematic diagram of an alternative structure for a medium-flexible rotary cutting component;

[0040] Figure 7 yes Figure 6 The main view;

[0041] Figure 8 yes Figure 3 A schematic diagram of an alternative structure for a medium-flexible rotary cutting component;

[0042] Figure 9 yes Figure 8 The main view;

[0043] Figure 10 yes Figure 3 A schematic diagram of an alternative structure for a medium-flexible rotary cutting component;

[0044] Figure 11 yes Figure 10 The main view;

[0045] Figure 12 yes Figure 3 A schematic diagram of an alternative structure for a medium-flexible rotary cutting component;

[0046] Figure 13 yes Figure 12 The main view;

[0047] Figure 14 yes Figure 3 A schematic diagram of an alternative structure for a medium-flexible rotary cutting component;

[0048] Figure 15 yes Figure 14 The main view;

[0049] Figure 16 yes Figure 3 A schematic diagram of an alternative structure for a medium-flexible rotary cutting component;

[0050] Figure 17 yes Figure 16 The main view;

[0051] Figure 18 This is a diagram of barbs;

[0052] Figure 19 yes Figure 18 An alternative schematic diagram;

[0053] Figure 20 This is a schematic diagram of the insertion of a thrombus aspiration catheter;

[0054] Figure 21 This is a schematic diagram of how a thrombus aspiration catheter works.

[0055] Explanation of reference numerals in the instruction manual's attached drawings: 101, Flexible tip; 102, Inner tube; 103, Inner tube cleaning connector; 201, Flexible rotary cutting assembly; 202, Handwheel; 203, Flexible rotary cutting head; 204, Middle tube; 205, Barb; 301, Outer tube; 401, Stress relief head; 402, Suction connector; 403, Motor switch; 404, Thumb drive; 405, Limit switch; 406, Battery; 407, Motor; 408, Driving gear; 409, Driven gear; 410, Spring; 411, Limit button; 501, Thrombus; 601, Guide wire. Detailed Implementation

[0056] The invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the invention, but the embodiments are not intended to limit the invention.

[0057] Reference Figures 1 to 19 As shown, the invention provides a novel thrombus aspiration catheter, comprising:

[0058] The housing is equipped with a suction connector 402; the suction connector 402 can be a universal Luer connector, which can be connected to an external interventional suction pump (e.g., a conventional negative pressure aspirator or other professional negative pressure suction device) to provide continuous suction negative pressure for thrombus 501 aspiration.

[0059] The inner tube 102 assembly includes an inner tube 102, a portion of which is located inside the housing and another portion is located outside the housing;

[0060] A rotary cutting assembly includes a middle tube 204 sleeved on an inner tube 102, a flexible rotary cutting head 203 located outside the outer shell, a rotary drive unit, an outer tube 301 (the outer tube 301 provides good flexibility and lubrication for instrument insertion), and a moving drive unit. The flexible rotary cutting head 203 includes multiple flexible heads and is connected to the distal end of the middle tube 204 (in some embodiments, the flexible rotary cutting head 203 and the middle tube 204 can be bonded, integrally injection molded, welded, or hinged and pressed together). The rotary drive unit is connected to the middle tube 204. The proximal end of 04 is used to drive the flexible rotary cutting head 203 to rotate and cut around the axis of the inner tube 102; the outer tube 301 is sleeved on the middle tube 204 and the proximal end of the outer tube 301 is sealed to the middle tube 204; the proximal end of the outer tube 301 is connected to the moving drive unit, which is configured to drive the outer tube 301 to move back and forth, for retracting or exposing the flexible rotary cutting head 203 outside the flexible rotary cutting head 203; the flexible head is provided with a plurality of barbs 205 arranged at a predetermined angle to the flexible head along its axial direction.

[0061] Specifically, the distal end of the thrombus 501 aspiration catheter of the present invention is equipped with a flexible cutting component 201, which can cut the thrombus 501 while aspirating it, facilitating aspiration and reducing blockage during the aspiration process. Additionally, the flexible cutting head 203 has barbs 205, which, when dealing with old thrombi 501, can wrap the thrombus 501 around the flexible cutting head 203 and bring it into the outer tube 301 for subsequent aspiration. The flexible cutting head 203 of this application is composed of multiple flexible components, possessing excellent flexibility and better wall-adhering performance. When removing thrombi 501 that adhere to the wall or from narrow and tortuous blood vessels, the flexible cutting head 203 can cut or wrap the thrombus 501, resulting in higher and more thorough removal efficiency without damaging the blood vessel wall. Furthermore, it can effectively block the cut thrombus 501, preventing it from migrating to other sites and causing secondary damage. In summary, the thrombus 501 aspiration catheter simultaneously performs thrombus 501 aspiration, thrombus 501 cutting, thrombus 501 entanglement, and free thrombus 501 blocking functions. This invention's thrombus 501 aspiration catheter has the advantages of being convenient to use, safe and effective, and multifunctional.

[0062] The flexible rotary cutting head 203 can be rotated by the handwheel 202 to cut the thrombus 501. Secondly, the flexible rotary cutting head 203 can wrap around the thrombus 501 and bring it into the outer tube 301 together and aspirate it out of the body.

[0063] Furthermore, the flexible rotary cutter head 203 is elastic. In some embodiments, the flexible rotary cutter head 203 may be made of polymer materials such as polyurethane, nylon, or silicone (a certain proportion of barium sulfate may be added to the polymer to give it good developability); or it may be made of other elastic materials.

[0064] Furthermore, the axes of the multiple flexible heads are set at a predetermined angle to the axis of the middle layer tube 204. The multiple flexible heads are arranged in a spiral around the axis of the middle layer tube 204. Specifically, the spiral arrangement allows the multiple flexible heads to be staggered when the outer tube 301 is sleeved on the flexible rotary cutter head 203 and the flexible rotary cutter head 203 is retracted, so that the diameter of the retracted flexible rotary cutter head 203 is smaller, which facilitates the retraction of the flexible rotary cutter head 203.

[0065] Furthermore, multiple flexible heads are arranged in multiple rows along the axial direction of the middle layer tube 204, with one row of flexible heads arranged in a circle along the axial direction.

[0066] Furthermore, the flexible cutting head 203 is spherical or umbrella-shaped. Specifically, a spherical flexible cutting head 203 can reduce the contact between the flexible cutting head 203 and the blood vessel wall while meeting cutting requirements. An umbrella-shaped flexible cutting head 203 can form a protective umbrella at the distal end, preventing the thrombus 501 from migrating to other parts of the body and causing secondary damage.

[0067] Furthermore, the lengths of the multiple flexible heads differ. In some embodiments, the flexible heads are of equal length.

[0068] Furthermore, the free end of the flexible tip has a rounded corner. For example, the rounded corner is a chamfered corner at the free end of the flexible tip. Alternatively, the rounded corner can be a hemispherical or spherical structure with a diameter larger than the diameter of the flexible tip itself. Specifically, the rounded corner helps prevent damage to the blood vessel wall when cutting the thrombus 501.

[0069] Furthermore, multiple rows of barbs 205 are arranged along the axis of the flexible head, and each row of barbs 205 has at least one barb 205.

[0070] Furthermore, multiple barbs 205 are spirally arranged around the axis of the flexible head multiple times.

[0071] Furthermore, the inner tube 102 assembly also includes a flexible tip 101, which is connected to the distal end of the inner tube 102. A step is provided at the end of the flexible tip 101 near the outer tube 301, and the minor and major diameters of the step match the inner and outer diameters of the outer tube 301. Specifically, when the flexible tip is retracted into the outer tube 301, the distal end of the outer tube 301 is engaged at the step, thereby forming a closed space between the middle tube 204 and the outer tube 301. This allows the thrombus 501 wrapped around the flexible tip to be easily extracted from the body via an interventional suction pump connected to the suction connector 402.

[0072] In some embodiments, the inner tube 102 assembly further includes an inner tube cleaning connector 103, which is connected to the proximal end of the inner tube 102. Instruments can be introduced to a predetermined location through the guidewire 601 via the inner tube 102, and related reagents can be injected or cleaned through the inner tube cleaning connector 103.

[0073] Furthermore, the rotary drive unit includes a manual drive component, an electric drive component, and a switching component for switching between the manual drive component and the electric drive component. Specifically, this embodiment can select either a manual low-speed rotating flexible rotary cutter head 203 or an electric high-speed rotating flexible rotary cutter head 203 as needed, further expanding its application range.

[0074] Furthermore, the manual drive includes a handwheel 202 fixedly connected to the interlayer tube 204, with the outer ring of the handwheel 202 protruding outside the housing. In some embodiments, the housing has an opening at the location where the handwheel 202 is provided, with the outer ring of the handwheel 202 protruding from the opening, thereby facilitating the turning of the handwheel 202 to rotate the interlayer tube 204 and the flexible rotary cutting head 203 connected to the interlayer tube 204 to cut and wrap the thrombus 501.

[0075] Furthermore, the electric drive unit includes a power unit (e.g., a motor 407), a driving gear 408, and a driven gear 409; the output end of the power unit is connected to the driving gear 408, the driving gear 408 meshes with the driven gear 409, and the driven gear 409 is coaxially connected to the interlayer tube 204. Thus, the power unit can drive the interlayer tube 204 and the flexible rotary cutting head 203 connected to the interlayer tube 204 to rotate and cut and wrap the thrombus 501. In some other embodiments, the electric drive unit can also be a chain connection, belt drive, or magnetic coupling drive. In some embodiments, the power unit can be powered by a built-in lithium battery 406, or it can be connected to a public power source or be charged. Thus, toggling the motor switch 403 can turn on the power, driving the motor 407 to rotate, thereby driving the driving gear 408 connected to the motor 407 to rotate, and further driving the driven gear 409 and the flexible rotary cutting assembly 201 to rotate and cut and wrap the thrombus 501. Furthermore, the power unit can provide different rotation speeds for the device.

[0076] Further, the switching component includes a limit switch 405, a limit member, a limit button 411, a limit pin, and an elastic member; the top of the limit switch 405 protrudes outside the housing, the middle part forms a sliding pair with the housing (for example, the housing has an opening at the position of the person with the limit switch 405, the top of the limit switch 405 protrudes outside the opening, and the middle part moves back and forth in the opening), and the bottom end is connected to the limit member. The bottom of the limit member has a slot, and the driven gear 409 of the electric drive component is located in the slot; the limit button 411 is slidably connected to the limit switch 405, and the bottom end of the limit button 411 has a limit pin whose axis is perpendicular to both the sliding direction of the limit button 411 and the axis of the middle tube 204; the elastic member is connected to the bottom end of the limit pin and is used to drive the limit pin to reset; the inner wall of the housing has limit grooves that cooperate with the limit pin at both ends of the travel of the limit switch 405. In some embodiments, the elastic member is a spring 410. In this embodiment, when high-speed rotary cutting is not required, the limit switch 405 can be toggled. At this time, the driven gear 409 disengages from the driving gear 408 and simultaneously disengages from the handwheel 202, disconnecting the connection. The flexible rotary cutting head 203 can then be rotated appropriately via the handwheel 202. When high-speed rotary cutting is needed, the limit switch 405 can be toggled to reconnect the driven gear 409 with the driving gear 408 and the handwheel 202. Specifically, in this embodiment, switching between manual and electric drive can be achieved by pressing the limit button 411, making it convenient to use and ensuring stable and reliable operation.

[0077] Furthermore, the moving drive unit includes a thumb drive 404 and a connecting tube connected to the thumb drive 404. The top end of the thumb drive 404 protrudes from the outer casing and moves back and forth along the axial direction of the outer tube 301. For example, the outer casing has a groove at the location where the thumb drive 404 is provided, the top end of the thumb drive 404 extends out of the groove, and the middle part of the thumb drive 404 moves back and forth in the groove. The bottom end of the thumb drive 404 is fixedly connected to the outer tube 301. In some embodiments, the bottom end of the thumb drive 404 is connected to the proximal end of the outer casing, and the suction connector 402 is also connected to the bottom end of the thumb drive 404.

[0078] In some embodiments, a stress relief head 401 is provided at the distal end of the housing. A through-hole is provided at the distal end of the stress relief head 401. The outer tube 301 passes through the through-hole. The stress relief head 401 can be made of polymer materials such as silicone, latex, or Pebax. The stress relief head 401 provides good flexible support performance, preventing the conduit from kinking.

[0079] Reference Figures 20-21 As shown, the usage process of this application is as follows (taking limb vein thrombosis removal surgery as an example):

[0080] During the procedure, routine pre-operative procedures are performed first, including puncturing the blood vessel using a puncture system, then inserting a suitable guidewire 601 through the puncture system and pushing it to the predetermined position. The inner tube cleaning connector 103 and the aspiration connector 402 are flushed with saline solution using a syringe. Then, the guidewire 601 is inserted into the inner tube 102 along the flexible tip 101, and the thrombus 501 aspiration catheter (hereinafter referred to as the "instrument") is pushed along the guidewire 601 to the predetermined position. Then connect the connecting tube of the negative pressure aspirator to the suction connector 402. Next, retract the thumb drive 404 to retract the outer tube 301. Once the flexible rotary cutting component 201 is fully exposed, rotate the handwheel 202 to wrap around and peel the thrombus 501 from the vessel wall. Turn on the negative pressure aspirator to continuously suction the outer tube 301. Then press the limit button 411 and move the limit switch 405 forward to connect the driven gear 409 to the handwheel 202 and the driving gear 408. Turn on the motor switch 403 to power on the rotation, driving the flexible rotary cutting component 201 to cut at high speed. Slowly move the instrument to aspirate the thrombus 501 out of the body. After aspiration is complete, turn the motor switch 403 to disconnect the circuit. Then press the limit button 411 and move the limit switch 405 backward to disengage the driven gear 409 from the handwheel 202. Push the thumb drive 404 forward to insert the flexible rotary cutting component 201 into the outer tube 301. Turn off the negative pressure aspirator and withdraw the instrument along the guidewire 601.

[0081] When dealing with narrow or tortuous blood vessels, the motor switch 403 can be toggled to disconnect the circuit as needed. The limit button 411 can be pressed to move the limit switch 405 backward to disengage the driven gear 409 from the handwheel 202. The handwheel 202 can be manually rotated to wrap the thrombus 501 around the flexible rotary cutting head 203. The thumb drive 404 can be pushed forward to insert the flexible rotary cutting component 201 into the outer tube 301. The handwheel 202 can be rotated in conjunction with negative pressure suction to remove the thrombus 501 from the body. Then the thumb drive 404 can be withdrawn. Once the flexible rotary cutting component 201 has completely leaked out, suction can be performed again. This process can be repeated until the thrombus 501 is removed.

[0082] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A novel thrombus aspiration catheter, characterized in that: include: The outer casing is equipped with a suction connector; An inner tube assembly includes an inner tube, a portion of which is located within the outer casing and another portion is located outside the outer casing; Rotary cutting assembly; The system includes an inner tube fitted onto the inner tube, a flexible rotary cutting head located outside the outer shell, a rotary drive unit, an outer tube, and a moving drive unit. The flexible rotary cutting head includes multiple flexible heads and is connected to the distal end of the inner tube. The rotary drive unit is connected to the proximal end of the inner tube and is used to drive the flexible rotary cutting head to rotate and cut around the axis of the inner tube. The outer tube is fitted onto the inner tube, and its proximal end is sealed to the inner tube. The proximal end of the outer tube is connected to the moving drive unit. The connection is configured to drive the outer tube to move back and forth, for retracting or exposing the flexible rotary cutting head when it is fitted outside the flexible rotary cutting head; the flexible head has a plurality of barbs arranged at a predetermined angle to the flexible head along its axial direction, the flexible rotary cutting head is elastic, the inner tube assembly also includes a flexible tip, the flexible tip is connected to the distal end of the inner tube; the flexible tip has a step at one end near the outer tube, the minor diameter and major diameter of the step are matched with the inner diameter and outer diameter of the outer tube.

2. The novel thrombus aspiration catheter according to claim 1, characterized in that: The axes of the plurality of flexible heads are set at a predetermined angle to the axis of the middle layer tube.

3. The novel thrombus aspiration catheter according to claim 1, characterized in that: The multiple flexible heads are arranged in a spiral around the axis of the middle layer tube.

4. The novel thrombus aspiration catheter according to claim 1, characterized in that: The multiple flexible heads are arranged in multiple rows along the axial direction of the middle layer tube, and each row of flexible heads is arranged in a circle along the axial direction.

5. The novel thrombus aspiration catheter according to claim 1, characterized in that: The flexible rotary cutting head is spherical or umbrella-shaped.

6. The novel thrombus aspiration catheter according to claim 1, characterized in that: The lengths of the multiple flexible heads differ.

7. The novel thrombus aspiration catheter according to claim 1, characterized in that: The free end of the flexible head has a rounded corner.

8. The novel thrombus aspiration catheter according to claim 1, characterized in that: The plurality of barbs are arranged in multiple rows along the axis of the flexible head, with each row of barbs having at least one barb.

9. The novel thrombus aspiration catheter according to claim 1, characterized in that: The multiple barbs are spirally arranged around the axis of the flexible head multiple times.

10. The novel thrombus aspiration catheter according to claim 1, characterized in that: The rotary drive unit includes a manual drive component, an electric drive component, and a switch component for switching between the manual drive component and the electric drive component.

11. The novel thrombus aspiration catheter according to claim 10, characterized in that: The manual drive unit includes a handwheel fixedly connected to the middle tube, with the outer ring of the handwheel protruding outside the housing.

12. The novel thrombus aspiration catheter according to claim 10, characterized in that: The electric drive unit includes a power unit, a drive gear, and a driven gear; the output end of the power unit is connected to the drive gear, the drive gear meshes with the driven gear, and the driven gear is coaxially connected to the middle layer tube.

13. The novel thrombus aspiration catheter according to claim 10, characterized in that: The switching component includes a limit switch, a limit element, a limit button, a limit pin, and an elastic element; The top of the limit switch protrudes outside the outer shell, the middle part forms a sliding pair with the outer shell, and the bottom end is connected to the limit member. The bottom of the limit member is provided with a slot, and the electric drive component is located in the slot. The limit button is slidably connected to the limit switch. The bottom end of the limit button is provided with a limit pin whose axis is perpendicular to both the sliding direction of the limit button and the axis of the middle tube. The elastic element is connected to the bottom end of the limit pin and is used to drive the limit pin to reset. The inner wall of the outer shell is provided with limit grooves at both ends of the movement stroke of the limit switch, which cooperate with the limit pin.

14. The novel thrombus aspiration catheter according to claim 1, characterized in that: The moving drive unit includes a thumb drive and a connecting tube connected to the thumb drive. The top end of the thumb drive protrudes from the outer shell and moves back and forth along the axial direction of the outer tube with the outer shell. The bottom end of the thumb drive is fixedly connected to the outer tube.

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