Thrombus taking-out device special for internal fistula in hemodialysis

Abstract

The utility model provides a special thrombus extraction device for internal fistula in hemodialysis, which is characterized in that a guide piece is arranged in a guide pipe in a penetrating manner, the guide pipe is arranged in a recovery pipe in a penetrating manner, a thrombus extraction frame which can be deformed and folded into the guide pipe is arranged at the far end of the guide piece, and the thrombus extraction frame comprises a plurality of thrombus extraction pieces which are transversely arranged at intervals in the circumferential direction; the thrombus taking pieces sequentially comprise cutting parts and collecting parts in the far-end direction, and thrombus taking diaphragms are arranged between the adjacent collecting parts. The recovery pipe is arranged in the positioning pipe in a penetrating manner, the far end of the recovery pipe is provided with a recovery frame which can be deformed and folded into the positioning pipe, the recovery frame comprises a plurality of recovery parts which are transversely arranged at intervals in the circumferential direction, a recovery diaphragm is arranged between every two adjacent recovery parts, and a recovery area with the inner diameter gradually increased in the far end direction is defined by the recovery parts and the recovery diaphragms; guide grooves are concavely formed in the inner sides of the recycling parts, and movement of the thrombus taking frame and the recycling frame is limited and guided by a guide structure so that the thrombus taking parts can always correspond to the guide grooves. Thrombus can be thoroughly removed.

Description

Technical Field

[0001] The utility model relates to the field of thrombus removal devices, in particular to a thrombus removal device dedicated to hemodialysis internal fistula. Background Art

[0002] Arteriovenous fistulas (AVFs) are the lifeline of hemodialysis patients. These include native arteriovenous fistulas (AVFs) and artificial arteriovenous fistulas (AVGs). A well-functioning AVF is a prerequisite for ensuring adequate dialysis.

[0003] Thrombosis leading to occlusion of the fistula is the primary cause of arteriovenous fistula failure and a common complication. The most commonly used method for fistula repair is percutaneous transluminal angioplasty (PTA) combined with thrombectomy, which can be divided into open thrombectomy and catheter-based thrombectomy.

[0004] Existing thrombectomy catheters utilize a catheter and a guidewire, which houses a stent, to facilitate thrombectomy. Specifically, the catheter is inserted into the blood vessel, extending across the thrombus to the distal end. The catheter is then withdrawn to release the stent, which is made of a memory material. After the stent expands, the guidewire is withdrawn, allowing the stent to drag the thrombus out of the vessel, completing the thrombus removal. However, because thrombi are fragile tissue formed by blood stasis, they are easily cut and fragmented during the dragging process by the stent, resulting in incomplete thrombus removal. If large pieces of thrombus tissue are transported by blood to the heart, brain, lungs, or other blood vessels, the consequences can be severe.

[0005] The purpose of this utility model is to design a thrombus removal device specifically for hemodialysis fistula that can completely remove thrombus in order to solve the problems existing in the above-mentioned prior art. Utility Model Content

[0006] In view of the problems existing in the above-mentioned prior art, the present invention provides a thrombus removal device specifically for hemodialysis internal fistula, which can effectively solve the problems existing in the above-mentioned prior art.

[0007] The technical solution of the utility model is:

[0008] A thrombus removal device specifically for hemodialysis internal fistula, comprising:

[0009] Positioning tubes, recovery tubes, catheters, and guide members driven by corresponding driving mechanisms to move along corresponding blood vessels;

[0010] The guide member is inserted into the catheter, which is inserted into the recovery tube. A thrombus removal frame is provided at the distal end of the guide member and can be deformed and retracted into the catheter. The thrombus removal frame includes a plurality of thrombus removal members arranged at intervals along the circumference and laterally. The plurality of thrombus removal members sequentially include a cutting portion and a collecting portion in the distal direction. A thrombus removal membrane is provided between adjacent collecting portions and is used to separate the distal ends of corresponding thrombi.

[0011] The recovery tube is inserted into the positioning tube and a recovery frame that can be deformed and retracted into the positioning tube is provided at the distal end. The recovery frame includes a plurality of recovery parts that are arranged at intervals along the circumference and laterally. A recovery diaphragm is provided between adjacent recovery parts for separating the proximal ends of the corresponding thrombi. The recovery parts and the recovery diaphragms together form a recovery area with an inner diameter gradually increasing toward the distal end. The inner sides of the recovery parts are all recessed with guide grooves extending along the length direction and adapted to the thrombus removal parts. The movement of the thrombus removal frame and the recovery frame is limited and guided by the guide structure so that the thrombus removal parts always correspond to the guide grooves.

[0012] Furthermore, the distal end of the inner hole of the catheter is set as a columnar accommodating area for accommodating the thrombus removal rack, and a flat guide area is set between the proximal end and the accommodating area. The distal end of the guide member is set as a support portion with a diameter smaller than that of the accommodating area, and a guide portion is set between the proximal end and the supporting portion to be adapted to and passed through the guide area. The thrombus removal rack is arranged on the supporting portion, and the inner wall of the positioning tube and the outer wall of the recovery tube are respectively provided with grooves and ridges that are interlocked and extend along the length direction. The guide structure includes the guide area, the guide portion, the grooves, and the ridges.

[0013] Furthermore, a cutting piece is provided in the distal end of the recovery tube, and the cutting piece includes an annular portion sleeved on the outside of the catheter, and a plurality of cutting ridges arranged at intervals along the circumferential direction on the outside of the annular portion and with ends connected to the inner wall of the recovery tube.

[0014] Furthermore, the distal ends of several of the cutting ridges are configured as cutting portions whose outer diameters gradually decrease toward the distal end.

[0015] Furthermore, a plurality of the cutting parts and the thrombus removal membranes enclose a cutting area with a gradually increasing inner diameter, and a plurality of the collecting parts enclose a collecting area with a gradually decreasing inner diameter.

[0016] Furthermore, the cutting area and the recovery area are set to corresponding cones, and the collection area is set to a hemispherical shape with an inner diameter adapted to the inner diameter of the corresponding blood vessel.

[0017] Furthermore, several of the recovery parts include, in sequence toward the distal direction, an outwardly extending expansion portion and a straight-line extending abutment portion, several of the distal ends of the abutment portions are provided with arc-shaped chamfers, several of the outer diameters of the abutment portions are adapted to the corresponding inner diameters of the blood vessels, several of the abutment portions and the outwardly extending expansion portions are provided with arc-shaped transitions, and several of the abutment portions and the outwardly extending expansion portions are provided with arc-shaped transitions.

[0018] Therefore, the present invention provides the following effects and / or advantages:

[0019] 1. The present application realizes the cooperation between the thrombus retriever and the retrieval frame, so that the positioning tube is moved to the proximal end of the corresponding thrombus and the catheter is moved to the distal end of the thrombus. The guide member does not move and retracts the catheter into the retrieval tube, thereby releasing the thrombus retriever at the distal end of the thrombus. The retrieval tube extends and releases the retrieval frame at the proximal end of the thrombus. When removing the thrombus, the retracting guide member pulls the thrombus retriever back toward the proximal end. The thrombus is first broken by several cutting parts and then enters the thrombus retriever, and then is completely caught by the thrombus retriever diaphragm and pulled back to the retrieval area and enters the retrieval tube. After the thrombus retriever enters the retrieval area, the guide member, the retrieval tube and the catheter are retracted synchronously, so that the retrieval frame embraces the thrombus retriever and deforms and retracts together into the positioning tube and then stops. Finally, the positioning tube, the retrieval tube, the catheter and the guide member are retracted together to separate from the blood vessel to complete the thrombus removal. The arrangement of the above structure can capture and recover the thrombus that has been broken by the several cutting parts through the thrombus removal diaphragm, and deform and shrink it into the positioning tube after the recovery frame embraces the thrombus removal frame, so as to fill the distal end of the positioning tube to prevent the thrombus from leaking out when the positioning tube is retracted, thereby completely removing the thrombus and avoiding the scattered large thrombus tissue from moving with the blood flow into the blood vessels such as the heart, brain, and lungs to cause serious consequences. At the same time, the thrombus is prevented from being too large in size by the breaking of the cutting part, which may block the recovery tube or squeeze and damage the thrombus removal diaphragm and the recovery diaphragm when recovering a large thrombus, thereby ensuring the stability of the thrombus removal process and extending the service life of the thrombus removal device. In addition, through the corresponding cooperation between the several thrombus removal members and the several guide grooves, when the thrombus removal frame enters the recovery area, not only the stability of the cooperation between the thrombus removal frame and the recovery frame is improved, but also the several thrombus removal members and the recovery members will not scratch the thrombus removal diaphragm and the recovery diaphragm, thereby further extending the service life of the thrombus removal device.

[0020] 2. The present application ensures that the thrombus removal frame and the recovery frame do not generate circumferential relative displacement during movement through the cooperation between the guide area and the guide part, and between the groove and the ridge, thereby ensuring that the multiple thrombus removal members always correspond to the multiple guide grooves. The above-mentioned guide structure will not cause damage to the blood vessels, and also has the characteristics of long stroke and high stability, and has a low manufacturing cost. While achieving the guiding function, it also improves practicality.

[0021] 3. In order to avoid the situation where a large number of thrombi in the blood vessels may cause the thrombi at the proximal end of the blood vessels to be directly squeezed into the recovery tube and block the recovery tube during the retraction of the thrombus removal stent, the present application sets up a number of cutting ridges to successively break up the thrombi at the proximal end of the blood vessels that are directly squeezed into the recovery tube, thereby avoiding blockage of the recovery tube, ensuring the stability of the thrombus removal process, and improving the adaptability of the thrombus removal device.

[0022] 4. In the present application, a plurality of cutting parts and a thrombus removal membrane are enclosed to form a cutting area with a gradually increasing inner diameter, so that the thrombus can be quickly broken up by the relatively sharp cutting area at the proximal end. Specifically, the cutting area and the recovery area are set to corresponding cones. When the thrombus removal frame enters the recovery area, the plurality of cutting parts are adapted to be embedded in the corresponding guide grooves, the plurality of collecting parts are located between the ends of the plurality of recovery parts, and the distal end of the recovery membrane is covered on the outside of the proximal end of the thrombus removal membrane, so that when the recovery frame and the thrombus removal frame are deformed and retracted into the positioning tube, the cooperation stability between the plurality of thrombus removal parts and the guide grooves is improved, and at the same time, it is avoided that the thrombus removal frame squeezes the plurality of recovery parts when entering the recovery area, causing the recovery parts to expand outward and damage the blood vessels, thereby improving the stability of the thrombus removal device.

[0023] It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The utility model provides a cross-sectional structural diagram of a thrombus removal device for hemodialysis internal fistula during thrombus removal.

[0025] Figure 2 for Figure 1 Schematic diagram of the local structure of the middle embolus removal frame.

[0026] Figure 3 for Figure 1 Schematic diagram of the local structure at the recovery rack.

[0027] Figure 4 for Figure 1 Schematic diagram of the partial structure of the middle guide and catheter.

[0028] Figure 5 A schematic diagram of the three-dimensional structure of a thrombus removal device for hemodialysis internal fistula provided by the utility model

[0029] Figure 6 for Figure 5 Schematic diagram of the local structure of the middle embolus removal frame.

[0030] Figure 7 for Figure 5 Schematic diagram of the local structure at the recovery rack.

[0031] Figure 8 This is a schematic diagram of the three-dimensional structure of the cutting piece provided by the utility model.

[0032] Figure 9 for Figure 5 Schematic diagram of the three-dimensional structure of the thrombectomy rack after entering the recovery area of the recovery rack. DETAILED DESCRIPTION

[0033] In order to facilitate understanding by those skilled in the art, the structure of the present invention is further described in detail with reference to the following embodiments and accompanying drawings:

[0034] refer to Figure 1-9 A thrombus removal device for hemodialysis fistula is specifically used to remove thrombi in the fistula blood vessels constructed by arteriovenous fistula surgery. The thrombus removal device includes:

[0035] The positioning tube 1, the retrieval tube 2, the catheter 3, and the guide member 4 are driven by corresponding driving mechanisms to move along the corresponding blood vessels. Specifically, after the positioning tube 1, the retrieval tube 2, the catheter 3, and the guide member 4 are inserted into the blood vessel to the corresponding positions with the assistance of imaging equipment, the distal ends of the positioning tube 1, the retrieval tube 2, the catheter 3, and the guide member 4 can be pulled or pushed by the driving mechanism to move toward the proximal end or the distal end within the blood vessel. The driving mechanism can be an operating handle connected to the proximal ends of the positioning tube 1, the retrieval tube 2, the catheter 3, and the guide member 4, respectively. The specific structure thereof is prior art and is not the invention of the present application, and will not be described in detail here.

[0036] The guide member 4 is inserted into the catheter 3, and the catheter 3 is inserted into the recovery tube 2. A thrombus removal frame 5 is provided at the distal end of the guide member 4, which can be deformed and retracted into the catheter 3. The thrombus removal frame 5 includes a plurality of thrombus removal members 51 arranged at intervals along the circumference and laterally. The plurality of thrombus removal members 51 include a cutting portion 511 and a collecting portion 512 in sequence toward the distal end. A thrombus removal membrane 52 is provided between adjacent collecting portions 512 to separate the distal ends of the corresponding thrombi.

[0037] The retrieval tube 2 is inserted into the positioning tube 1 and is provided with a retrieval frame 6 at the distal end thereof which can be deformed and retracted into the positioning tube 1. The retrieval frame 6 includes a plurality of retrieval members 61 arranged at intervals along the circumference and laterally. A retrieval membrane 62 is provided between adjacent retrieval members 61 for separating the proximal ends of the corresponding thrombi. The retrieval members 61 and the retrieval membrane 62 enclose a retrieval area 63 with an inner diameter gradually increasing toward the distal end. The inner sides of the retrieval members 61 are recessed and provided with guide grooves 611 extending along the length direction and adapted to the thrombus removal members 51. The movement of the thrombus removal frame 5 and the retrieval frame 6 is guided by the guide structure so that the thrombus removal members 51 always correspond to the guide grooves 611. Specifically, the thrombus removal frame 5 and the retrieval frame 6 are made of shape memory material. The proximal end of the thrombus removal frame 5 is fixedly connected to the guide member 4, and the distal end is provided with a sliding sleeve 55 slidably sleeved on the guide member 4.

[0038] Specifically, the traction wire is first passed through the blood vessel to the proximal end of the thrombus, the positioning tube 1 is moved along the traction wire to the proximal end of the corresponding thrombus and then the traction wire is withdrawn, and the recovery tube 2 with the catheter 3 and the guide 4 is passed through the positioning tube 1, and the catheter 3 is moved to the distal end of the thrombus. The guide 4 does not move and the catheter 3 is retracted into the recovery tube 2, thereby releasing the thrombus removal frame 5 at the distal end of the thrombus, and the recovery tube 2 extends to release the recovery frame 6 at the proximal end of the thrombus. When removing the thrombus, the guide 4 is retracted to pull the thrombus removal back toward the proximal end. The thrombus is first broken up by the cutting parts 511 and then enters the thrombus removal frame 5, and is then completely held by the thrombus removal membrane 52 and pulled back to the recovery area 63 and enters the recovery tube 2. After the thrombus removal frame 5 enters the recovery area 63, the guide member 4, the recovery tube 2 and the catheter 3 are retracted synchronously, so that the recovery frame 6 embraces the thrombus removal frame 5 and deforms and retracts together into the positioning tube 1 and then stops. Finally, the positioning tube 1, the recovery tube 2, the catheter 3 and the guide member 4 are retracted together to separate from the blood vessel to complete the thrombus removal.

[0039] The above-described structure allows the thrombus detachment membrane 52 to capture and recover the thrombus that has been broken up by the cutting portions 511. The retrieval frame 6 then embraces the thrombus detachment membrane 5 and deforms and retracts the thrombus into the positioning tube 1, filling the distal end of the positioning tube 1. This prevents the thrombus from leaking out when the positioning tube 1 is retracted, thereby completely removing the thrombus and preventing large pieces of scattered thrombus tissue from being transported with the blood flow into blood vessels such as the heart, brain, and lungs, causing serious consequences. Furthermore, the breaking up of the thrombus by the cutting portions 511 prevents the thrombus from becoming too large, which could block the retrieval tube 2 or damage the thrombus detachment membrane 52 and the retrieval membrane 62 during retrieval. This ensures the stability of the thrombus detachment process and extends the service life of the thrombus retrieval device. Furthermore, the corresponding engagement of the thrombus detachment members 51 with the guide grooves 611 improves the stability of the engagement between the thrombus detachment member 5 and the retrieval frame 6 when the thrombus detachment member 5 enters the retrieval area 63. Furthermore, the thrombus detachment members 51 and the retrieval member 61 do not scratch the thrombus detachment membrane 52 and the retrieval membrane 62, further extending the service life of the thrombus retrieval device.

[0040] In order to achieve the stability of the cooperation between the thrombus removal frame 5 and the recovery frame 6, the distal end of the inner hole of the catheter 3 is set as a columnar accommodating area 31 for accommodating the thrombus removal frame 5, and a flat guide area 32 is set between the proximal end and the accommodating area 31. The distal end of the guide member 4 is set as a support part 41 with a diameter smaller than the accommodating area 31, and a guide part 42 is set between the proximal end and the support part 41 to adapt to the guide area 32 and pass through the guide area 32. The thrombus removal frame 5 is arranged on the support part 41, and the inner wall of the positioning tube 1 and the outer wall of the recovery tube 2 are respectively provided with a groove 11 and a ridge 21 that are interlocked and extend along the length direction. The guide structure includes the guide area 32, the guide part 42, the groove 11, and the ridge 21. Therefore, through the cooperation between the guide area 32 and the guide part 42, and the cooperation between the groove 11 and the ridge 21, the thrombus removal frame 5 and the recovery frame 6 will not produce circumferential relative displacement during movement, so that the multiple thrombus removal members 51 always correspond to the multiple guide grooves 611. The above-mentioned guiding structure will not cause damage to the blood vessels, and also has the characteristics of long-stroke cooperation and high stability, and has a low manufacturing cost. While achieving the guiding function, it also improves practicality.

[0041] When there are a large number of thrombi in the internal fistula, the thrombus retriever 5 is released at the distal end of the most distal thrombus and then slowly pulled back toward the proximal end. During the pullback process, the thrombus at the distal end may be cut by the cutting portion 511 and enter the thrombus retriever 5, filling the thrombus. The thrombus at the proximal end of the vessel may be directly squeezed into the recovery tube 2, blocking the recovery tube 2. To ensure the stability of the thrombus removal process, a cutting member 22 is provided in the distal end of the recovery tube 2. The cutting member 22 includes an annular portion 221 that is sleeved on the outside of the catheter 3 and a plurality of cutting ribs 222 that are circumferentially spaced outside the annular portion 221 and whose ends are connected to the inner wall of the recovery tube 2. The plurality of cutting ribs 222 can sequentially break up the thrombus at the proximal end of the vessel that is directly squeezed into the recovery tube 2, preventing blockage of the recovery tube 2, ensuring the stability of the thrombus removal process, and improving the adaptability of the thrombus removal device.

[0042] In order to further improve the thrombus-breaking effect of the cutting ridges 222, the distal ends of several of the cutting ridges 222 are provided with cutting blades 223 whose outer diameters gradually decrease toward the distal end.

[0043] In order to improve the crushing effect of the cutting part 511 and the accommodating space of the collecting part 512, the cutting parts 511 and the thrombus removal membrane 52 are enclosed to form a cutting area 53 with a gradually increasing inner diameter, so that the thrombus can be quickly crushed by the proximal sharper cutting area 53. Specifically, the cutting area 53 and the recovery area 63 are set to corresponding cones. When the thrombus removal frame 5 enters the recovery area 63, the cutting parts 511 are adapted to be embedded in the corresponding guide grooves 611, and the collecting parts 512 are located between the ends of the recovery parts 61, and the distal end of the recovery membrane 62 is covered on the outside of the proximal end of the thrombus removal membrane 52, so that the recovery frame 6 embraces the thrombus removal frame 5 together. When deformed and retracted into the positioning tube 1, the matching stability between the several thrombus removal members 51 and the guide groove 611 is improved, and at the same time, it is avoided that the thrombus removal frame 5 enters the recovery area 63 and squeezes the several recovery members 61, causing the recovery members 61 to expand outward and damage the blood vessel, thereby improving the stability of the thrombus removal device. The several collecting parts 512 are enclosed to form a collection area 54 with a gradually decreasing inner diameter. Specifically, the collection area 54 is set to a hemispherical shape with an inner diameter adapted to the corresponding inner diameter of the blood vessel, thereby maximizing the volume of the collection cavity. Specifically, after the thrombus removal frame 5 is released during thrombus removal, the proximal ends of the several collecting parts 512 can be set to abut the inner wall of the blood vessel and slightly expand the blood vessel outward to achieve a close fit, thereby completely holding the thrombus.

[0044] To prevent damage to the blood vessel caused by the retrieval frame 6 and the thrombectomy frame 5, several of the retrieval members 61 include, in sequence, an outwardly extending, obliquely extending, expansion portion 612 and a linearly extending abutment portion 613 toward the distal end. Several of the abutment portions 613 have arcuate chamfers at their distal ends. The outer diameters of several of the abutment portions 613 match the inner diameters of the corresponding blood vessels. Several of the abutment portions 613 and the expansion portion 612 have arcuate transitions. Specifically, when the retrieval frame 6 is released for thrombectomy, the abutment portions 613 abut the inner wall of the blood vessel and slightly expand the blood vessel outward to achieve a tight fit, thereby completely retrieving the thrombus. This improves the overall flexibility of the retrieval frame 6 and the thrombectomy frame 5, preventing scratches or punctures in the blood vessel.

[0045] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A thrombus removal device for hemodialysis fistula, characterized in that: include: A positioning tube (1), a recovery tube (2), a catheter (3), and a guide member (4) driven by a corresponding driving mechanism to move along a corresponding blood vessel; The guide member (4) is inserted into the catheter (3), and the catheter (3) is inserted into the recovery tube (2). A thrombus removal frame (5) is provided at the distal end of the guide member (4) and can be deformed and retracted into the catheter (3). The thrombus removal frame (5) includes a plurality of thrombus removal members (51) arranged at intervals along the circumference and arranged transversely. The plurality of thrombus removal members (51) include cutting portions (511) and collecting portions (512) in sequence toward the distal end. A thrombus removal membrane (52) for separating the distal ends of the corresponding thrombi is provided between adjacent collecting portions (512); The recovery tube (2) is inserted into the positioning tube (1) and is provided with a recovery frame (6) at the distal end thereof that is deformable and retractable into the positioning tube (1). The recovery frame (6) includes a plurality of recovery members (61) arranged at intervals in the circumferential direction and arranged transversely. A recovery diaphragm (62) for separating the proximal ends of the corresponding thrombi is provided between adjacent recovery members (61). The plurality of recovery members (61) and the recovery diaphragm (62) are enclosed to form a recovery area (63) with an inner diameter gradually increasing toward the distal end. The inner sides of the plurality of recovery members (61) are all recessed and provided with a guide groove (611) extending in the length direction and adapted to the plurality of thrombus removal members (51). A cutting member (22) is provided in the distal end of the recovery tube (2). The cutting member (22) includes an annular portion (221) sleeved on the outer side of the catheter (3). The distal end of the inner hole of the catheter (3) is provided with a columnar accommodation area (31) for accommodating the thrombus removal frame (5), and a flat guide area (32) is provided between the proximal end and the accommodation area (31). The distal end of the guide member (4) is provided with a support portion (41) having a diameter smaller than that of the accommodation area (31), and a guide portion (42) adapted to and passed through the guide area (32) is provided between the proximal end and the support portion (41). The thrombus removal frame (5) is provided with On the support portion (41), the inner wall of the positioning tube (1) and the outer wall of the recovery tube (2) are respectively provided with grooves (11) and ridges (21) that fit together and extend along the length direction, and the guide structure includes the guide area (32), the guide portion (42), the grooves (11), and the ridges (21); the movement of the thrombus removal frame (5) and the recovery frame (6) is limited and guided by the guide structure so that the plurality of thrombus removal members (51) always correspond to the plurality of guide grooves (611).

2. The thrombus removal device for hemodialysis internal fistula according to claim 1, characterized in that: The cutting member (22) further comprises a plurality of cutting ridges (222) which are arranged at intervals along the circumferential direction on the outside of the annular portion (221) and whose ends are connected to the inner wall of the recovery pipe (2).

3. The thrombus removal device for hemodialysis internal fistula according to claim 2, characterized in that: The distal ends of the plurality of cutting ridges (222) are provided with cutting blades (223) whose outer diameters gradually decrease toward the distal end.

4. The thrombus removal device for hemodialysis internal fistula according to claim 1, characterized in that: The plurality of cutting parts (511) and the thrombus removal membrane (52) enclose a cutting area (53) with a gradually increasing inner diameter, and the plurality of collecting parts (512) enclose a collecting area (54) with a gradually decreasing inner diameter.

5. The thrombus removal device for hemodialysis internal fistula according to claim 4, characterized in that: The cutting area (53) and the recovery area (63) are set to corresponding cones, and the collecting area (54) is set to a hemispherical shape with an inner diameter adapted to the inner diameter of the corresponding blood vessel.

6. The thrombus removal device for hemodialysis internal fistula according to claim 4, characterized in that: Several of the recovery parts (61) include, in sequence toward the distal direction, an outwardly extending expansion part (612) and a straightly extending abutment part (613); the distal ends of several of the abutment parts (613) are provided with arc-shaped chamfers; the outer diameters of several of the abutment parts (613) are adapted to the corresponding inner diameters of the blood vessels; an arc-shaped transition is provided between several of the abutment parts (613) and the outwardly extending expansion part (612); and an arc-shaped transition is provided between several of the abutment parts (613) and the outwardly extending expansion part (612).

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