A thrombus aspiration catheter

Abstract

This invention discloses a thrombus aspiration catheter, comprising a catheter body and a suction head. A main drainage window is provided on one end face of the suction head, and an integrally formed vortex flow channel is coaxially arranged inside the suction head. The catheter body is a dual-lumen polymer tube, including a central main suction cavity and an annular auxiliary drainage cavity surrounding the main suction cavity. A drainage cavity opening is provided on the edge of the end face of the suction head away from the catheter body, and this opening communicates with the annular auxiliary drainage cavity. This invention, by setting a dual-lumen polymer tube and a suction head, and providing a main drainage window for communication with the main suction cavity, a vortex flow channel, and a drainage cavity opening for communication with the annular auxiliary drainage cavity on the suction head, achieves basic thrombus aspiration and, when aspirating highly concentrated thrombi, dilutes the thrombus by delivering saline solution, thereby improving the aspiration efficiency for refractory thrombi.

Description

Technical Field

[0001] This utility model belongs to the field of medical device technology, and in particular relates to a thrombus aspiration catheter. Background Technology

[0002] Percutaneous thrombectomy is a key technique for treating diseases such as acute myocardial infarction and peripheral arterial embolism. Currently, most thrombectomy catheters used in clinical practice are single-lumen structures. They work by applying negative pressure to the proximal end of the catheter and using the opening at the tip of the catheter to draw the thrombus in and remove it from the body.

[0003] When traditional aspiration catheters encounter large or tough thrombi, the thrombus is very likely to block the opening at the tip of the catheter, causing the aspiration process to be interrupted. The operator needs to repeatedly withdraw the catheter to clean it, which not only prolongs the operation time, but may also cause thrombus fragments to break off and cause distal embolism during withdrawal. In addition, for high-density thrombi that are tightly adhered to the blood vessel wall, the negative pressure of a single aspiration port is not enough to effectively remove them, resulting in limited aspiration efficiency. Utility Model Content

[0004] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a thrombus aspiration catheter to solve the technical problems mentioned in the background art.

[0005] This utility model provides the following technical solution: A thrombus aspiration catheter includes a catheter body and an aspiration head connected to the distal end of the catheter body. The aspiration head has a blunt, rounded end face away from the catheter body. At least one main drainage window is also provided on the end face of the aspiration head away from the catheter body. An integrally formed vortex channel is coaxially provided inside the aspiration head, and the outlet of the main drainage window is connected to the inlet of the vortex channel. The catheter body is a dual-lumen polymer tube, including a central main aspiration cavity and an annular auxiliary drainage cavity surrounding the main aspiration cavity. The end of the main aspiration cavity near the aspiration head is coaxially connected to the outlet of the vortex channel, allowing material flowing through the vortex channel to enter the main aspiration cavity. An opening for a drainage cavity is also provided on the edge of the end face of the aspiration head away from the catheter body, and this opening is connected to the annular auxiliary drainage cavity via an annular transition drainage cavity.

[0006] Preferably, the dual-cavity polymer tube includes an outer polymer tube and an inner polymer tube coaxially disposed inside the outer polymer tube. The inner ring of the inner polymer tube is the main suction cavity, and the outer polymer tube and the inner polymer tube form the annular auxiliary drainage cavity. The outer polymer tube and the inner polymer tube are connected by multiple radial support ribs.

[0007] Preferably, one end of the inner polymer tube, away from the suction head, is connected to a negative pressure pump.

[0008] Preferably, a syringe connector is provided on the outer side of the outer polymer tube away from the aspiration head. The syringe connector is in communication with the inside of the annular auxiliary drainage cavity. The syringe connector can be connected to a syringe containing physiological saline. A one-way inlet valve is also provided inside the syringe connector.

[0009] Preferably, the radial support rib group includes a plurality of radial support ribs, which are evenly distributed radially around the axial direction of the inner polymer tube; the plurality of radial support rib groups are distributed sequentially along the length direction of the inner polymer tube.

[0010] Preferably, the number of main drainage windows is set to four, and the four main drainage windows are evenly distributed around the axial direction of the suction head. The outlets of each main drainage window converge and connect to a single inlet of the vortex channel or correspond to different inlet sections of the vortex channel.

[0011] Preferably, the vortex channel is a single-headed right-handed spiral channel, and the axis of the vortex channel coincides with the axis of the guide tube body.

[0012] Preferably, the opening of the drainage cavity is a plurality of micropores evenly distributed around the axial direction of the suction head, or a continuous annular slit.

[0013] Preferably, the annular transition drainage cavity is coaxially disposed inside the suction head, and one end of the annular transition drainage cavity away from the opening of the drainage cavity is coaxially disposed with the annular auxiliary drainage cavity.

[0014] Preferably, a variable stiffness support layer is embedded along the entire length of the inner wall of the outer polymer tube, and the proximal and distal ends of the variable stiffness support layer are respectively connected to the proximal and distal tube wall materials of the outer polymer tube.

[0015] Preferably, the variable stiffness support layer is composed of a laser-engraved nickel-titanium alloy tube, and the perforation rate of the perforated pattern on the tube wall of the nickel-titanium alloy tube exhibits a continuous gradient change from the far end to the near end of the outer polymer tube body, that is, the perforation rate of the perforated pattern on the tube wall of the nickel-titanium alloy tube gradually decreases from the far end to the near end of the outer polymer tube body.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention relates to a thrombus aspiration catheter, which is equipped with a double-lumen polymer tube and an aspiration head. The aspiration head is provided with a main drainage window for communication with the main aspiration cavity, a vortex flow channel, and a drainage cavity opening for communication with the annular auxiliary drainage cavity. This enables basic aspiration of thrombi and, when aspirating thrombi with high concentrations, the delivery of physiological saline is used to dilute the thrombi, thereby improving the aspiration efficiency of refractory thrombi. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of this utility model.

[0019] Figure 2 This is a schematic diagram of the suction head structure of this utility model.

[0020] Figure 3 This is a schematic diagram of the main drainage window structure of this utility model.

[0021] Figure 4 This is a schematic diagram of the conduit body structure of this utility model.

[0022] In the figure: 1. Tube body; 2. Suction head; 21. Main drainage window; 22. Vortex flow channel; 23. Drainage cavity opening; 24. Annular transition drainage cavity; 3. Main suction cavity; 4. Annular auxiliary drainage cavity; 5. Outer polymer tube body; 6. Inner polymer tube body; 7. Radial support ribs; 8. Variable stiffness support layer. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0024] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0025] This utility model provides a thrombus aspiration catheter, see reference. Figure 1-4 As shown, the device includes a catheter body 1 and an aspiration head 2 connected to the distal end of the catheter body 1. The end face of the aspiration head 2 away from the catheter body 1 has a blunt rounded structure. This blunt rounded structure design effectively reduces the compression of the thrombus when the aspiration head 2 is advanced. At least one main drainage window 21 is also provided on the end face of the aspiration head 2 away from the catheter body 1. An integrally formed vortex channel 22 is also coaxially provided inside the aspiration head 2. The outlet of the main drainage window 21 is connected to the inlet of the vortex channel 22. The catheter body 1 is a dual-lumen polymer. The tubing body, a dual-lumen polymer tubing, includes a central main suction chamber 3 and an annular auxiliary drainage chamber 4 surrounding the main suction chamber 3. One end of the main suction chamber 3 near the suction head 2 is coaxially connected to the outlet of the vortex channel 22, allowing material flowing through the vortex channel 22 to enter the main suction chamber 3. The edge of the suction head 2, away from the catheter body 1, is also provided with a drainage chamber opening 23, which communicates with the annular auxiliary drainage chamber 4 via an annular transition drainage chamber 24. Several main drainage windows 21 are provided at the edge, allowing the suction head 2 to begin suction as soon as it approaches the thrombus, avoiding the drawback of traditional end-hole catheters that require the thrombus to be pressed against them to function. After the thrombus is drawn in through the main drainage window 21, it first enters the vortex channel 22, where a certain rotational shear force is generated, effectively breaking up larger thrombi into smaller fragments, thereby effectively preventing blockage of the catheter body 1.

[0026] The dual-lumen polymer tubing includes an outer polymer tubing 5 and an inner polymer tubing 6 coaxially disposed inside the outer polymer tubing 5. The inner ring of the inner polymer tubing 6 is the main aspiration chamber 3. The outer polymer tubing 5 and the inner polymer tubing 6 form the annular auxiliary drainage chamber 4. The outer polymer tubing 5 and the inner polymer tubing 6 are connected by multiple radial support ribs 7. The coaxial dual-lumen structure separates the aspiration and perfusion functions. The main aspiration chamber 3 is responsible for extracting thrombus fragments broken by vortexing, while the annular auxiliary drainage chamber 4 is used for perfusion with physiological saline. The two functions do not interfere with each other.

[0027] One end of the inner polymer tube 6, away from the suction head 2, is used to connect to a negative pressure pump.

[0028] A syringe connector is provided on the outer side of the outer polymer tube 5, away from the aspiration head 2. The syringe connector communicates with the interior of the annular auxiliary drainage cavity 4 and can connect to a syringe filled with physiological saline. A one-way inlet valve is also provided inside the syringe connector. The one-way inlet valve prevents blood from flowing back into the annular auxiliary drainage cavity 4 during aspiration, ensuring the cleanliness and unobstructed flow of the perfusion channel. The syringe allows the operator to easily control the perfusion rate and flow of physiological saline.

[0029] The radial support rib group 7 includes several radial support ribs, which are evenly distributed radially around the axial direction of the inner polymer tube 6; multiple radial support rib groups 7 are distributed sequentially along the length direction of the inner polymer tube 6. The radial support rib group 7 can position the inner polymer tube 6 at the center of the outer polymer tube 5, ensuring that the main suction cavity 3 always maintains a stable flow cross section, and can also resist the possible collapse and deformation of the main suction cavity 3 during negative pressure suction. At the same time, the setting of the radial support rib group 7 enhances the overall structural strength.

[0030] The system comprises four main drainage windows 21, which are evenly distributed around the axial direction of the suction head 2. The outlets of each main drainage window 21 converge and connect to a single inlet of the vortex channel 22 or correspond to different inlet sections of the vortex channel 22. The four circumferentially evenly distributed main drainage windows 21 can capture thrombi from all directions, significantly increasing the aspiration area. The multiple main drainage windows 21 jointly supply material to the vortex channel 22, ensuring that even if some main drainage windows 21 are temporarily blocked, the others can still function normally, thus improving the system's reliability.

[0031] The vortex channel 22 is a single-headed right-handed spiral channel, and the axis of the vortex channel 22 coincides with the axis of the catheter body 1. This allows the material flowing through the vortex channel 22 to enter the main suction chamber 3. The spiral channel with the coincident axis generates a uniform rotating flow field, avoiding unnecessary turbulence and energy loss, and ensuring the consistency and efficiency of thrombus fragmentation.

[0032] The drainage cavity opening 23 is a plurality of micropores evenly distributed around the axial direction of the aspiration head 2, or a continuous annular slit. The drainage cavity opening 23 is located behind the main drainage window 21. The saline solution flowing from the drainage cavity opening 23 forms a gentle perfusion flow. This fluid mainly diffuses towards the area between the vessel wall and the outer wall of the aspiration head 2, flushing and diluting the high-density thrombus attached to the vessel wall, making it loose and easier for the main aspiration flow field to capture, thereby significantly improving the aspiration efficiency for refractory thrombi. The design of the micropores or annular slits can form a uniform and gentle circumferential perfusion flow, avoiding the formation of high-speed jets impacting the thrombus and causing distal embolism, while ensuring that the thrombus throughout the vessel wall is diluted.

[0033] The annular transition drainage cavity 24 is coaxially disposed inside the suction head 2, and one end of the annular transition drainage cavity 24 away from the drainage cavity opening 23 is coaxially disposed with the annular auxiliary drainage cavity 4. The coaxially disposed annular transition drainage cavity 24 realizes a smooth transition from the annular auxiliary drainage cavity 4 of the catheter body 1 to the drainage cavity opening 23, minimizing fluid resistance and ensuring uniform distribution of the infusion fluid.

[0034] A variable stiffness support layer 8 is embedded along the entire length of the inner wall of the outer polymer tube 5. The proximal and distal ends of the variable stiffness support layer 8 are connected to the proximal and distal wall materials of the outer polymer tube 5, respectively. A variable stiffness support layer 8 is also embedded along the entire length of the inner wall of the inner polymer tube 6. The variable stiffness support layer 8 provides the necessary radial support and anti-flattening ability for the entire catheter, ensuring that the catheter lumen will not collapse during negative pressure aspiration, while maintaining the flexibility required for the catheter to pass through tortuous blood vessels.

[0035] The variable stiffness support layer 8 is composed of a laser-engraved nickel-titanium alloy tube. The perforation rate of the perforated pattern on the tube wall of the nickel-titanium alloy tube exhibits a continuous gradient change from the distal end to the proximal end of the outer polymer tube body 5; that is, the perforation rate of the perforated pattern on the tube wall of the nickel-titanium alloy tube gradually decreases from the distal end to the proximal end of the outer polymer tube body 5. The gradient perforation rate allows for the regulation of catheter stiffness. The higher perforation rate at the distal end ensures that the catheter tip is flexible and can safely pass through tortuous blood vessels; the lower perforation rate at the proximal end provides sufficient pushing force and anti-bending ability, allowing the operator to better control the catheter position. This stiffness transition design improves the maneuverability and passage of the catheter.

[0036] Working principle: During use, the catheter is advanced to the vicinity of the thrombus under the guidance of the guidewire. The proximal end of the main aspiration chamber 3 is connected to the negative pressure pump, and the proximal end of the annular auxiliary drainage chamber 4 is connected to a syringe filled with normal saline through a syringe connector with a one-way inlet valve. After the negative pressure is activated, the thrombus is aspirated from the main drainage window 21, broken up in the vortex channel 22, and then extracted through the main aspiration chamber 3. At the same time, normal saline can be slowly injected, and the perfusion fluid flowing out from the opening 23 of the drainage chamber dilutes the thrombus at the vessel wall and assists the aspiration process.

[0037] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A thrombus aspiration catheter, comprising a catheter body (1) and an aspiration head (2) connected to the distal end of the catheter body (1), characterized in that: The suction head (2) has a blunt circular structure at one end face away from the catheter body (1). At least one main drainage window (21) is also provided on the end face of the suction head (2) away from the catheter body (1). An integrally formed vortex flow channel (22) is also provided coaxially inside the suction head (2). The outlet of the main drainage window (21) is connected to the inlet of the vortex flow channel (22). The catheter body (1) is a double-lumen polymer tube body. The double-lumen polymer tube body includes a main suction cavity (3) located in the center and a surrounding cavity. An annular auxiliary drainage chamber (4) is located outside the main suction chamber (3); one end of the main suction chamber (3) near the suction head (2) is coaxially connected to the outlet of the vortex channel (22), so that the material flowing through the vortex channel (22) can enter the main suction chamber (3); a drainage chamber opening (23) is also provided on the edge of the end face of the suction head (2) away from the guide tube body (1), and the drainage chamber opening (23) is connected to the annular auxiliary drainage chamber (4) through an annular transition drainage chamber (24).

2. The thrombus aspiration catheter according to claim 1, characterized in that, The dual-cavity polymer tube includes an outer polymer tube (5) and an inner polymer tube (6) coaxially disposed inside the outer polymer tube (5). The inner ring of the inner polymer tube (6) is the main suction cavity (3). The outer polymer tube (5) and the inner polymer tube (6) form the annular auxiliary drainage cavity (4). The outer polymer tube (5) and the inner polymer tube (6) are connected by multiple radial support ribs (7).

3. The thrombus aspiration catheter according to claim 2, characterized in that, The radial support rib group (7) includes several radial support ribs, which are evenly distributed radially around the axial direction of the inner polymer tube (6); multiple radial support rib groups (7) are distributed sequentially along the length direction of the inner polymer tube (6).

4. The thrombus aspiration catheter according to claim 1, characterized in that, The number of main drainage windows (21) is set to four. The four main drainage windows (21) are evenly distributed around the axial direction of the suction head (2). The outlets of each main drainage window (21) converge and connect to a single inlet of the vortex channel (22) or correspond to different inlet sections of the vortex channel (22).

5. The thrombus aspiration catheter according to claim 1, characterized in that, The vortex channel (22) is a single-head right-handed spiral channel, and the axis of the vortex channel (22) coincides with the axis of the conduit body (1).

6. The thrombus aspiration catheter according to claim 1, characterized in that, The drainage cavity opening (23) is a number of micro-holes evenly distributed around the suction head (2) axially, or a continuous annular slit.

7. The thrombus aspiration catheter according to claim 1, characterized in that, The annular transition drainage cavity (24) is coaxially disposed inside the suction head (2), and one end of the annular transition drainage cavity (24) away from the drainage cavity opening (23) is coaxially disposed with the annular auxiliary drainage cavity (4).

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