Thrombus aspiration catheter

Abstract

This invention relates to a thrombus aspiration catheter, comprising: an aspiration tube extending along an axis and having an aspiration port at its distal end; a guidewire connected to the distal end of the aspiration tube, its proximal end fixed to the outer periphery of the aspiration tube, the portion of the guidewire overlapping with the aspiration tube forming a connecting section, and the portion extending distally forming a suspended section; the aspiration tube includes an aspiration section and a main body section, the bending stiffness of the aspiration section and the guidewire being less than the bending stiffness of the main body section; or, the inner wall of the aspiration tube has a groove extending distally along the axis, the distal end of the groove having a receiving section, and a connecting rod, the distal end of which is fixed to the proximal end of the guidewire. This application, through guidewire deformation or embedding of the guidewire into the aspiration tube wall, enables rapid reaching of a predetermined position using the guidewire without damaging the cross-sectional area of ​​the aspiration cavity of the aspiration tube, thereby simultaneously improving the aspiration efficiency and pushing performance of the aspiration tube.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and in particular to thrombus aspiration catheters. Background Technology

[0002] A thrombus is an abnormal blood clot that forms at the site of damage or repair to the inner wall of a blood vessel in the cardiovascular system. It consists of insoluble fibrin, deposited platelets, accumulated white blood cells, and trapped red blood cells. When a thrombus forms and blocks a blood vessel, it interrupts blood flow and causes serious clinical consequences. For example, coronary artery blockage leads to myocardial infarction, cerebral artery blockage leads to cerebral infarction, pulmonary artery blockage causes pulmonary embolism, and arteriovenous embolism in the limbs causes limb infarction. All of these conditions can be life-threatening and require timely intervention.

[0003] For the treatment of thrombosis, thrombectomy is widely used in clinical practice due to its advantages such as simplicity, rapid removal, and low cost. Existing aspiration catheters typically include single-lumen and double-lumen structures. Single-lumen catheters, lacking a guidewire lumen, suffer from poor advancement performance due to the absence of a guidewire. Double-lumen catheters, with both parallel aspiration and guidewire lumens, have a smaller cross-sectional area due to the guidewire lumen reducing the volume of the aspiration lumen within a given catheter diameter, resulting in lower aspiration efficiency and a higher risk of blockage. Summary of the Invention

[0004] Based on this, this application provides a thrombus aspiration catheter, comprising: an aspiration tube extending along an axis and having an aspiration port at its distal end; a guidewire tube for the guidewire to pass through and connected to the distal end of the aspiration tube; the proximal end of the guidewire tube is fixed to the outer periphery of the aspiration tube, the portion overlapping with the aspiration tube forming a connecting section and the portion extending distally forming a suspended section, the length of the suspended section being 1-3 times the length of the connecting section; the aspiration tube includes an aspiration section and a main body section, the bending stiffness of the aspiration section and the guidewire tube being less than the bending stiffness of the main body section; or, the inner wall of the aspiration tube has... The groove extends along the axis to the distal end. The suction tube has an outlet hole communicating with the groove on its outer periphery. The guide wire can enter from the distal end of the suction tube and exit through the outlet hole. The distal end of the groove has a receiving section. The stiffness of the side wall of the receiving section near the axis is 0.1-0.7 times that of the side wall away from the axis. The groove also includes a connecting rod that slides through the groove. Its distal end is fixed to the proximal end of the guide wire tube. Under the action of the connecting rod, the guide wire tube can be completely retracted into the receiving section or slide out of the receiving section.

[0005] Furthermore, the guide wire is fixedly connected to the suction tube, and the outer layer of the guide wire is made of a polymer composite material with a hardness of 25D-35D.

[0006] Furthermore, the outer layer of the suction tube is made of a polymer composite material, the hardness of the outer layer of the suction section is 35D-45D, and the hardness of the outer layer of the main body section is 45D-72D.

[0007] Furthermore, the hardness of the outer layer of the main body segment decreases in a step-like or gradual manner from the proximal end to the distal end.

[0008] Furthermore, the main body segment also has an intermediate reinforcing layer, which is located between the outer and inner layers of the suction tube.

[0009] Furthermore, the guide wire is slidably connected to the suction tube, and at least one reinforcing member is provided on the outer periphery of the distal end of the suction tube.

[0010] Furthermore, the proximal end of the guide wire tube has a constricted portion, and the connecting rod is fixedly connected to the constricted portion.

[0011] Furthermore, the proximal side of the groove includes a sliding section, the cross-sectional area of ​​the receiving section is larger than that of the sliding section, and a step is formed at the connection between the two.

[0012] Furthermore, it also includes an elastic member disposed in the receiving section, the distal end of the constricted portion having an enlarged portion, the connecting rod being connected to the enlarged portion, one end of the elastic member abutting against the step, and the other end abutting against the enlarged portion.

[0013] Furthermore, the suction port is a slanted cut, and one or both sides of its distal end have a pointed tip, and / or, one or both sides of the suction port are provided with a cutting portion.

[0014] Furthermore, the outlet end of the guide wire is configured with a bevel.

[0015] The technical solution of the present invention has the following beneficial effects:

[0016] The suction tube of this application is attached with a guide wire, which is deformed or embedded in the wall of the suction tube. The presence of the guide wire guides the suction tube without affecting its suction cross-sectional area, and does not require increasing the size of the sheath tube, thus simultaneously improving the suction efficiency and pushing performance of the suction tube. Attached Figure Description

[0017] Figure 1 This is an overall structural diagram of the thrombus aspiration catheter in the first embodiment;

[0018] Figure 2 This is a first three-dimensional structural diagram of the thrombus aspiration catheter in the first embodiment;

[0019] Figure 3 This is a second three-dimensional structural diagram of the thrombus aspiration catheter in the first embodiment;

[0020] Figure 4 This is a cross-sectional view of the thrombus aspiration catheter in the first embodiment;

[0021] Figure 5 A labeled cross-sectional view of the thrombus aspiration catheter in the first embodiment.

[0022] Figure 6 This is a schematic diagram of the thrombus aspiration catheter entering the sheath in the first embodiment;

[0023] Figure 7 This is a three-dimensional structural diagram of the thrombus aspiration catheter in the second embodiment;

[0024] Figure 8 This is an exploded view of the thrombus aspiration catheter in the second embodiment;

[0025] Figure 9 This is a cross-sectional view of the thrombus aspiration catheter in the second embodiment;

[0026] Figure 10a This is a structural diagram of the connection between the guide wire tube and the connecting rod in the second embodiment;

[0027] Figure 10b This is a structural diagram of the connection between the guide wire tube and the connecting rod in another embodiment;

[0028] Figure 11 This is a cross-sectional view of the suction tube in the second embodiment;

[0029] Figure 12 This is a three-dimensional structural diagram of the guide wire entering the suction tube in the second embodiment;

[0030] Figure 13 for Figure 12 Sectional view in;

[0031] Figure 14 A cross-sectional view of the guide wire entering the suction tube in another embodiment;

[0032] Figure 15 for Figure 14 Enlarged view of point A in the image;

[0033] Figure 16 This is a structural diagram of the suction port in another embodiment;

[0034] Figure 17 A cross-sectional view of a thrombus aspiration catheter in another embodiment;

[0035] Figure 18 for Figure 17 Enlarged view of point B in the image. Detailed Implementation

[0036] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0037] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intermediate element present. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intermediate element present. The terms "upper," "lower," "left," "right," and similar expressions used to indicate orientation are for illustrative purposes only and do not represent the only possible implementation.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0039] It should be noted that, for medical devices, the end of the medical device that is relatively closer to the operator is generally called the "proximal end," and the end of the medical device that is relatively farther from the operator is called the "distal end." Based on this principle, the "proximal end" and "distal end" of any component of the delivery system are defined. "Axial" or "longitudinal axis" refers to the direction parallel to the line connecting the center of the distal end and the center of the proximal end of the medical device. "Radial" or "lateral" refers to the direction perpendicular to the axial direction.

[0040] First Embodiment

[0041] See Figure 1As shown, this embodiment provides a thrombus aspiration catheter 100, including an aspiration tube 20 extending axially, with an aspiration port 21 at its distal end. The aspiration tube 20 includes an aspiration section 20a and a main body section 20b sequentially from distal to proximal. The aspiration section 20a is a portion located at the distal end of the aspiration tube 20 (on the side where the aspiration port 21 is located), with a length of 5-30 mm. When the aspiration port 21 is configured as a slanted cut, the aspiration section 20a is the section containing the aspiration port 21, and its length is approximately the projected length of the aspiration port 21 along the axial direction. In this application, "approximately" indicates a deviation within ±10%. The main body section 20b is the remaining portion of the aspiration tube 20 after removing the aspiration section 20a, and it is integrally formed with or fixedly disposed with the aspiration section 20a. A guidewire 10 is disposed on the opposite side of the aspiration port 21. The proximal end of the suction tube 20 is connected to the catheter seat 30, which can be connected to a negative pressure source to achieve negative pressure suction of the suction tube 20. The bending stiffness of the suction section 20a and the guide wire tube 10 is less than that of the main body section 20b.

[0042] See Figure 2-4 As shown, the thrombus aspiration catheter 100 will continue to be described. The aspiration tube 20 extends axially and has a distal aspiration port 21. This aspiration port 21 has a beveled structure, and the angle of inclination of the beveled surface is between 15° and 75°. Compared to a circular aspiration port, this beveled aspiration port can increase the aspiration area by 15% to 50%, increase the aspiration flow rate, increase the probability of aspirating wall-adhering thrombi, and improve aspiration efficiency. In other embodiments, the aspiration port may also be a distal opening of the aspiration tube, i.e., not a beveled opening.

[0043] The outer layer of the suction tube 20 is a continuous monolith, which can be generated by extrusion. The extruded material can be one or more thermoplastic polymers with different hardnesses mixed in different proportions. This thermoplastic material includes one or more of polyether block amide, polyamide, polyurethane, or block polyether amide resin PEBAX. Considering that for the above-mentioned thermoplastic polymers or mixtures thereof, when they constitute the outer layer of the suction tube 20, under the same dimensions, higher hardness results in greater flexural stiffness, the hardness of the outer layer of the suction section 20a is set to 36D-45D, and the hardness of the outer layer of the main body section 20b is set to 46D-72D. For the outer layer of the main body section 20b, its hardness can increase progressively from 46D to 72D from the distal end to the proximal end, or it can increase in a step manner from 46D to 72D, thereby increasing the stiffness of the main body section 20b from the distal end to the proximal end. For example, the second outer layer can sequentially include four regions along its length, from the distal end to the proximal end. The hardness of these four regions can be set to 46D, 55D, 60D, and 72D. Using these hardness settings, the bending stiffness of the suction section is less than that of the main body section, making the suction section easier to bend than the main body section. Furthermore, because the main body section uses a variable hardness setting, its stiffness increases sequentially from the distal end to the proximal end, giving the main body section 20b good compliance and pushing performance. For the entire suction tube 20, its outer layer hardness increases sequentially from the distal end to the proximal end, making it easier to bend closer to the distal end of the suction tube 20.

[0044] In this embodiment, no intermediate reinforcing layer is provided in the suction section 20a, while an intermediate reinforcing layer is provided in the main body section 20b, located between the outer and inner layers of the suction tube 20. The intermediate reinforcing layer can be a single layer, which can be a braided layer or a helical spring layer. Alternatively, the intermediate layer can be double-layered, comprising both a braided layer and a helical spring layer. In this embodiment, by providing an intermediate reinforcing layer in the main body section but not in the suction section, the bending rigidity of the main body section can be further improved, increasing the stiffness difference between the main body section 20b and the suction section 20a, making the suction section 20a easier to bend relative to the main body section 20b.

[0045] See Figure 2As shown, two tips 22 are provided at the distal end of the aspiration port 21, i.e., at the connection between the aspiration port 21 and the guidewire 10. The two tips 22 are located on opposite sides of the aspiration port 21, i.e., at different positions along the circumference of the guidewire 10. In this embodiment, by providing the tips 22, the aspiration tube 20 can loosen the thrombus during travel or thrombus aspiration, causing the thrombus to break or detach from the blood vessel wall, facilitating subsequent aspiration operations. In other embodiments, the tips 22 may be provided only on one side.

[0046] The guidewire 10 has a two-layer structure, including an inner guidewire layer and an outer guidewire layer. The outer guidewire layer is made of one or more of block polyetheramide resin, thermoplastic polyurethane elastomer, and polyamide, with a hardness of 25D-35D. The inner guidewire layer is made of PTFE. By adopting the above hardness setting, the bending stiffness of the guidewire 10 is less than that of the suction section. Therefore, the guidewire 10 is more flexible and easier to bend than the suction section 20a.

[0047] See also Figure 1 As shown, the guidewire 10 has an inlet end 11 on the distal side and an outlet end 12 on the proximal side, including a connecting section 10a and a suspended section 10b. The guidewire 10 and the suction tube 20 are arranged parallel to each other along the axial direction. The portion of the guidewire 10 that overlaps with the suction tube 20 along the axial direction constitutes the connecting section 10a, while the portion extending distally constitutes the suspended section 10b. At least part or all of the connecting section 10a of the guidewire 10 is fixedly connected to the opposite side of the suction port 21, while the suspended section 10b continues to extend from the distal end of the connecting section 10a into a suspended state. In actual use, the guidewire 40 can enter the guidewire 10 from the inlet end 11 and exit from the outlet end 12. In this embodiment, the outlet end 12 is configured as a bevel. The beveled outlet end 12 can achieve a smooth connection between the distal end of the guidewire tube 10 and the suction tube 20, thereby allowing the distal end face of the guidewire tube 10 to smoothly transition to the outer periphery of the suction tube 20, preventing the distal end face of the guidewire tube 10 from protruding from the outer periphery of the guidewire tube 10 and causing damage to the blood vessel.

[0048] In this embodiment, the difference in bending stiffness is achieved by controlling the hardness distribution of the outer layers of the suction tube and the guide wire, as well as whether or not an intermediate reinforcing layer is provided. For example, in this embodiment, the guide wire 10 has only two layers, and its outer layer has a hardness of 25D-35D, while the suction section 20a of the suction tube 20 has a hardness of 36D-45D, and the main body section 20b has a hardness of 46D-72D. Furthermore, the suction section 20a does not have an intermediate reinforcing layer, while the main body section 20b does. Through these settings, the guide wire 10 itself and the suction section 20a are more prone to bending deformation under compressive force. The stiffness of the suction tube 20 increases sequentially from the distal end to the proximal end, with the lowest stiffness at the suction section 20a. This makes the distal side of the entire suction tube 20, especially the suction section 20a, more susceptible to bending deformation.

[0049] See Figure 5 As shown, the length L1 of the suspended section 10b is at least 1-3 times the length L2 of the connecting section 10a. Given a fixed total length of the guide wire 10, the longer the length L1 of the suspended section 10b, the easier it is for the suspended section 10b to bend.

[0050] With the above configuration, the suction tube 20 can be inserted into a sheath 200 of the same type (i.e., the inner diameter of the sheath tube is equal to the outer diameter of the suction tube). See also Figure 6 As shown, when the suction tube 20 is inserted into the sheath 200 of the same type, since the inner diameter of the sheath 200 is smaller than the sum of the outer diameters of the guidewire 10 and the suction tube 20, the suction tube 20 and the guidewire 10 will be subjected to compressive force from the inside of the sheath 200. Because the guidewire 10 is cantilevered, and the bending stiffness of both the suction section 20a and the guidewire 10 is smaller than the bending stiffness of the main body section 20b, under this compressive force, the suction tube 20 will bend counterclockwise, causing the connected suction section 20a to also bend, allowing the suction tube 20 to enter the sheath 200 of the same type. Once it reaches the predetermined position, the suction tube 20 extends out of the sheath 200 and returns to its original shape.

[0051] In summary, on the one hand, given a fixed outer diameter of the aspiration tube 20, its entire lumen can be used as an aspiration chamber, and the guidewire 10 does not occupy the volume of the aspiration chamber, nor does it reduce the cross-sectional area of ​​the aspiration chamber. On the other hand, since the aspiration tube can be delivered using a sheath 200 of the same type, there is no need to increase the size of the sheath 200, and the guidewire 10 does not affect the delivery performance of the aspiration tube. Finally, the presence of the guidewire 10 allows the guidewire 40 to pass through and guide the aspiration tube 20, thereby enabling the aspiration tube 20 to quickly reach the target position under the guidance of the guidewire 40, improving the efficiency of the surgery. Therefore, for the thrombus aspiration catheter 100 of this embodiment, it can guide the aspiration tube 20 with the guidewire 10 while minimizing the impact of the guidewire 10 on the aspiration cross-sectional area of ​​the aspiration tube 20, without increasing the size of the sheath 200, thus balancing delivery performance and aspiration efficiency, preventing thrombus blockage, and adapting to small-sized blood vessels.

[0052] Second Embodiment

[0053] The thrombus aspiration catheter in this embodiment is basically the same as that in the first embodiment, except that the guidewire and aspiration tube are slidably connected in this embodiment.

[0054] See Figure 7-9 As shown, the suction catheter 100a in this embodiment includes a suction tube 20 and a guide wire tube 10, which are slidably connected to the suction tube 20. The distal end of the suction tube 20 has a suction port 21, which is a beveled cut. The inner wall of the suction tube 20 has a groove 23 extending axially to the distal end. An outlet hole 24 communicating with the groove 23 is provided on the outer periphery of the suction tube 20. The guide wire 40 can extend from the distal end of the suction tube 20 into the groove 23 and exit through the outlet hole 24. To facilitate the creation of the groove 23 at the distal end of the suction tube 20, a plane perpendicular to the axis of the suction tube 20 is cut at the distal end of the suction tube 20. The groove 23 is created with this plane as the starting position, and pointed portions 22 are formed on both sides of this plane. The end of the connecting rod 50 is connected to the guide wire tube 10 and is used to drive the guide wire tube 10 to slide axially. The connecting rod 50 can drive the guide wire tube 10 to retract into the receiving section 23b or slide out from the receiving section 23b.

[0055] See Figure 10aAs shown, the distal end of the connecting rod 50 is fixedly connected to the proximal end of the guidewire tube 10. The connecting rod 50 can be made of a metallic material, such as a compliant nickel-titanium alloy, which has good elasticity and pushing performance. The proximal end of the guidewire tube 10 has a constriction 13, which is tapered and gradually decreases in cross-sectional area from the proximal end to the distal end along the axial direction until it is close to the cross-sectional area of ​​the connecting rod 50. The connecting rod 50 is connected to the proximal end of the constriction 13, and the outlet end 12, which is obliquely cut, is provided on the constriction 13. Considering that the size of the guidewire tube 10 is larger than that of the connecting rod 50, the constriction 13 is used to achieve a stable connection between the connecting rod 50 and the guidewire tube 10. The tension or thrust applied by the connecting rod 50 can be uniformly transmitted to the guidewire tube 10 circumferentially through the constriction 13, thereby ensuring that the guidewire tube 10 moves well along the axis under the action of the connecting rod 50.

[0056] See Figure 10b As shown, in other embodiments, a disc-shaped enlarged portion 14 may be provided at the distal end of the constricted portion 13. The cross-sectional area of ​​the enlarged portion 14 is larger than the cross-sectional area at the distal end of the constricted portion 13. The connecting rod 50 is connected to the enlarged portion 14, that is, the enlarged portion 14 is located between the connecting rod 50 and the constricted portion 13.

[0057] See Figure 11 The structure of the suction tube 20 is further explained below. The groove 23 includes a sliding section 23a and a receiving section 23b connected sequentially from the proximal end to the distal end, with a step 26 formed at the connection between the two. The receiving section 23b is an expandable hole located on the proximal side of the suction tube 20, with a cross-sectional area larger than that of the sliding section 23a and a length greater than that of the guide wire 10, thereby achieving complete accommodating of the suction tube 20. In this embodiment, the sliding section 23a is mainly used for sliding of the connecting rod 50, while the receiving section 23b is mainly used to accommodate the retracted guide wire 10. In other embodiments, the groove can also be a through-hole structure with a constant cross-sectional area, i.e., without a step.

[0058] The receiving section 23b is anisotropic in the circumferential direction, exhibiting different mechanical properties in different directions of the circumference. Within the receiving section of the suction tube 20, the outer layer has a higher stiffness than the inner layer. Specifically, the stiffness of the sidewall of the receiving section near the center of the suction tube (i.e., the inner sidewall of the suction tube) is 0.1-0.7 times the stiffness of the sidewall away from the center of the suction tube (i.e., the outer sidewall of the suction tube). In this embodiment, this can be achieved by using different materials, such as using PEBAX for the outer layer and TPU for the inner layer, or using PEBAX for both layers, resulting in a harder outer layer than the inner layer. With these settings, most deformation occurs within the inner layer of the suction tube when the guide tube enters the receiving section, causing the receiving section to expand inwards while the outer diameter of the suction tube 20 remains essentially unchanged. Furthermore, at least one reinforcing member 25 is provided on the outer periphery of the receiving section of the suction tube 20. The reinforcing member 25 is used to enhance the rigidity of the receiving section, further strengthening its structural rigidity and reducing the expansion of the outer layer when the guide wire enters the receiving section. The reinforcing member 25 can be directly embedded into the inner wall of the suction tube 20, and a groove can be provided on the outer periphery of the suction tube 20 to embed the reinforcing member into the groove. Exemplarily, the reinforcing member 25 includes two first reinforcing members 25a and a second reinforcing member 25b. The second reinforcing member 25b is annular, while the first reinforcing member 25a is located on the opposite side of the obliquely cut suction port 21. To prevent obstruction of the suction port 21, the first reinforcing member 25a is configured as a fan-shaped strip structure.

[0059] See Figure 12-13 As shown, when the guidewire 10 needs to be retracted into the receiving section 23b, the connecting rod 50 can be pulled proximally to drive the guidewire 10 to slide along the groove 23 and gradually enter the receiving section 23b until it is completely contained within the receiving section 23b. When the suction tube 20 enters the receiving section 23b, it will be squeezed against the inner wall of the receiving section 23b. This squeezing force will cause the suction tube 20 to shrink and the receiving section 23b to expand. At this time, the inner layer of the suction tube 20 located in the receiving section will expand into the inner cavity, while the outer diameter profile remains basically unchanged. This allows the suction tube 20 to still pass through the same type of sheath after it is retracted into the receiving section 23b, without being affected by the retraction of the guidewire 10.

[0060] During use, when the guidewire 40 is not in use, the connecting rod 50 can be pulled to retract the guidewire tube 10 into the receiving hole 23b. Since the increase in the outer contour of the suction tube 20 in this state is very small or negligible, the suction tube 20 can be delivered using a sheath of the same type. When the suction tube 20 reaches the lesion site in the body, the connecting rod 50 is pushed forward to extend the guidewire tube 10 out of the receiving section 23b. At this time, since the guidewire tube 10 is already outside the receiving section 23b, the inner layer of the guidewire tube 10 at the receiving section will recover its deformation and will no longer expand towards the lumen side due to compression. This allows the cross-sectional area of ​​the suction cavity in the suction section of the suction tube 20 to return to the lumen area of ​​the suction tube, improving suction efficiency.

[0061] When it is necessary to insert the aspiration tube 20 along the guidewire 40, the connecting rod 50 can be pushed forward to extend the guidewire tube 10 out of the receiving section 23b. Externally, the guidewire 40 is passed sequentially through the guidewire tube 10, the groove 23, and out through the exit hole 24. Then, the connecting rod 50 is retracted to retract the guidewire tube 10 containing the guidewire 40 into the aspiration chamber and delivered into the body through the sheath. Once the aspiration tube 20 reaches the lesion site under the guidance of the guidewire 40, the connecting rod 50 is pushed forward again to extend the guidewire tube 10 out of the receiving section 23b to increase the aspiration area.

[0062] When the thrombus aspiration is completed and the aspiration tube 20 needs to be withdrawn from the body, the connecting rod 50 can be retracted to allow the guidewire 10 to retract into the aspiration tube 20 for delivery through a sheath of the same type. With this configuration, the presence of the guidewire 10 does not increase the size of the sheath, making it easier to access smaller blood vessels. Therefore, in this embodiment, by slidingly connecting the guidewire 10 and the aspiration tube 20, its outline size can be reduced for easier delivery when delivery through the sheath 200 is required, while the aspiration cross-sectional area can be restored during aspiration to improve aspiration efficiency.

[0063] See Figure 14-15 As shown, in other embodiments, to facilitate the extension of the guide wire 10 from the receiving section 23b, an elastic element 60 is also provided in the receiving section 23b. This elastic element 60 can be a spiral spring or an elastic rod, etc. One end of the elastic element 60 can abut against the step 26, and the other end can abut against the enlarged portion 14. When the guide wire 10 enters the receiving section 23b, the elastic element 60 is compressed. At this time, the guide wire 10 can be kept in the receiving section 23b by keeping the connecting rod 50 stationary relative to the suction tube 20 via the handle. When it is necessary to withdraw the guide wire 10 from the receiving section 23b, the restriction on the handle is released, and the guide wire 10 will automatically pop out of the receiving section 23b under the elastic restoring force of the elastic element 60, thus eliminating the need for subsequent pushing actions.

[0064] See Figure 16As shown, in other embodiments, cutting sections 28 for cutting thrombi can also be provided on one or both sides of the suction port 21. The cutting sections 28 are serrated or wavy, used to cut or loosen thrombi, facilitating the aspiration of thrombi that have been formed for a long time and are tough in texture. During thrombus aspiration, the suction tube 20 can be moved back and forth along the guidewire, using the cutting sections 28 to contact and loosen the attached thrombi. During loosening, a negative pressure device draws the thrombus from the suction chamber. This design significantly improves the thrombus clearance rate and accuracy, increases thrombus aspiration efficiency, and shortens the operation time.

[0065] See Figure 17-18 As shown, in other embodiments, a connector 70 is provided to facilitate the guide wire 40's entry into the groove 23 and exit through the outlet hole 24. The connector 70 is a block structure with at least two vertically arranged connecting legs 71 on one end face. Connecting holes (not shown in the figure) corresponding to the connecting legs 71 are provided on the guide wire 40 and the connecting rod 50, respectively. A marking point 51 is provided on the connecting rod 50, and the distance between the connecting hole and the marking point 51 is less than the radius of the outlet hole 24. When the end face of the guide wire 40 is aligned with the marking point 51, the connecting holes on the guide wire 40 and the connecting rod 50 are also vertically aligned. At this time, the connecting legs 71 on the connector 70 are inserted into the corresponding connecting holes, thereby connecting the guide wire 40 and the connecting rod 50. After the connector 70 connects the guide wire 40 and the connecting rod 50, during the process of pulling the connecting rod 50 into the groove 23, the connecting rod 50 will drive the guide wire 40 to move together to the outlet hole 24. When the connector 70 reaches the outlet hole 24, the connector 70 is separated from the connecting rod 50 and the guide wire 40, and the connection between them is released. Then, the end of the guide wire 40 can be pulled to extend the guide wire 40 out of the outlet hole 24. In order to ensure that the connector 70 has reached the outlet hole 24 before the guide wire tube 10 is fully inserted into the slide groove 23 so as to facilitate the removal of the connector 70, in this embodiment, it is assumed that the distance between the center of the outlet hole 24 and the far end of the suction tube 20 is L4, the distance between the marker point 51 and the far end of the connecting rod 50 is L3, and the length of the guide wire tube 10 is L5, then L3 + L5 > L4 is required.

[0066] For the connector 70, in other embodiments, a rope or strap can also be used. When the end face of the guide wire 40 is aligned with the mark point 51, the guide wire 40 and the connecting rod 50 are tied together and fixed in a slip knot near the mark point 51. Then, when the connector 70 reaches the outlet hole 24, the slip knot is untied to disconnect the guide wire 40 from the connecting rod 50.

[0067] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. The scope of protection of this patent should be determined by the appended claims.

Claims

1. Thrombus aspiration catheter, characterized in that The application relates to a catheter device, comprising: a suction tube extending along an axis and having a suction port at a distal end; a guide wire tube for a guide wire to pass through and connected to a distal side of the suction tube; an inner wall of the suction tube has a sliding groove extending along the axis to the distal end, the suction tube has a lead-out hole communicated with the sliding groove, the guide wire can enter from the distal end of the suction tube and pass out from the lead-out hole, the distal end of the sliding groove has a containing section, a side wall of the containing section close to the center of the suction tube has a rigidity of 0.1-0.7 times that of the other side, and the device further comprises a connecting rod slidingly arranged in the sliding groove, a distal end of the connecting rod is fixed to a proximal end of the guide wire tube, and under the driving of the connecting rod, the guide wire tube can be completely retracted into the containing section or slide out of the containing section.

2. The thrombus aspiration catheter of claim 1, wherein, The guide wire tube is slidingly connected to the suction tube, and at least one reinforcing member is arranged at the containing section.

3. The thrombus aspiration catheter of claim 2, wherein, The proximal end of the guide wire tube has a necking portion, and the connecting rod is fixedly connected to the necking portion.

4. The thrombus aspiration catheter of claim 3, wherein, The proximal end side of the sliding groove comprises a sliding section, the containing section has a larger cross-sectional area than the sliding section, and a step is formed at the connection position of the two sections.

5. The thrombus aspiration catheter of claim 4, wherein, The device further comprises an elastic member arranged in the containing section, the distal end of the necking portion has an enlarged portion, the connecting rod is connected to the enlarged portion, one end of the elastic member is abutted against the step, and the other end is abutted against the enlarged portion.

6. The thrombus aspiration catheter of any of claims 1-5, wherein, The suction port is a bevelled port, one side or both sides of the distal end of the suction port further has a pointed portion, and / or one side or both sides of the suction port further has a cutting portion.

7. The thrombus aspiration catheter of any of claims 1-5, wherein, The outlet end of the guide wire tube is arranged as a bevelled port.

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