Suction catheter and suction system

Abstract

The utility model provides a suction catheter and a suction system, and relates to the technical field of medical instruments. According to the suction catheter, the outer diameter of the suction catheter can be kept small, and the suction flow speed and suction force can be improved by fully utilizing a large catheter cavity of the guide catheter. The suction catheter comprises a catheter piece, an expansion piece, a fluid assembly and a developing piece. Wherein the guide pipe piece is provided with a suction flow channel; the expansion part is arranged on the outer wall of the near end of the catheter part, the expansion part and the outer wall of the catheter part are connected in a sealed mode and define an expansion cavity, and the expansion part is elastic; the fluid assembly is connected with the pipe wall of the guide pipe piece, extends to the position corresponding to the expansion cavity and is provided with a fluid channel, and the fluid channel communicates with the expansion cavity; the developing part is arranged on the far-end part of the catheter part and used for displaying the position of the far-end part of the catheter part.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a suction catheter and suction system. Background Technology

[0002] Percutaneous transluminal coronary intervention (PCI) is an interventional procedure that uses minimally invasive catheter techniques to open narrowed or blocked coronary arteries and improve blood supply to the heart. It is commonly used to treat coronary heart disease, acute myocardial infarction, and other conditions. The core steps of PCI include puncturing the blood vessel, catheter guidance, balloon dilation, and stent implantation. PCI is characterized by its minimal invasiveness and rapid recovery.

[0003] During PCI surgery, blood clots are typically removed from blood vessels using an aspiration catheter. However, aspiration catheters are often quite large, particularly in outer diameter, making them difficult to insert into smaller blood vessels. Utility Model Content

[0004] This application provides a suction catheter and suction system that can keep the suction catheter with a small outer diameter, which is beneficial to make full use of the larger lumen of the catheter to increase the suction flow rate and suction force.

[0005] On one hand, this application provides a suction catheter, which includes: a catheter component, an expansion component, a fluid assembly, and a developing component; wherein, the catheter component has a suction flow channel; the expansion component is disposed on the outer wall of the proximal end of the catheter component, the expansion component is sealed to the outer wall of the catheter component and surrounds it to form an expansion cavity, and the expansion component is elastic; the fluid assembly is connected to the wall of the catheter component and extends to a position corresponding to the expansion cavity, the fluid assembly has a fluid channel, and the fluid channel communicates with the expansion cavity; the developing component is disposed on the distal end of the catheter component, and the developing component is used to display the position of the distal end of the catheter component.

[0006] The aspiration catheter provided in this embodiment has an expansion member on its outer wall. By delivering fluid into the expansion cavity formed by the expansion member and the catheter, the volume of the expansion member can be changed. This allows the expansion member to fill the gap between the catheter and the guiding tube, facilitating the generation of a higher negative pressure within the catheter during aspiration. Furthermore, a contrast agent is located at the distal end of the catheter, enabling real-time and rapid determination of the distal end's position within the blood vessel, facilitating physician confirmation of whether the distal end is close to a thrombus. Simultaneously, by connecting the fluid assembly to the catheter wall and extending the fluid assembly to a position corresponding to the expansion cavity, fluid can be delivered into the expansion cavity through the fluid channel of the fluid assembly. This structural design allows the fluid assembly to be installed using the conduit wall, eliminating the need to attach the fluid assembly to the inner or outer wall of the conduit. This prevents the fluid assembly from protruding completely from the outer wall of the conduit, thus avoiding changes to the overall radial dimension of the suction conduit. Consequently, the suction conduit can maintain a smaller outer diameter, which is beneficial for fully utilizing the larger lumen of the conduit to increase the suction velocity and suction force.

[0007] In one possible implementation of this application, the conduit includes a barrier layer, a retaining layer, and an adjusting layer. The barrier layer encloses and forms a suction channel, the retaining layer covers the barrier layer to restrict the radial movement of the barrier layer, and the adjusting layer covers the retaining layer.

[0008] In one possible implementation of this application, the strength of the retaining layer is greater than the strength of the regulating layer; and / or, the strength of the retaining layer is greater than the strength of the blocking layer.

[0009] In one possible implementation of this application, the adjustment layer includes at least two adjustment segments, which are sequentially distributed along the axial direction of the catheter. Among two adjacent adjustment segments, the adjustment segment closer to the proximal end of the catheter has a greater hardness than the adjustment segment farther from the proximal end of the catheter.

[0010] In one possible implementation of this application, the portion of the fluid assembly that connects to the pipe wall extends within the pipe wall along the axial direction of the conduit.

[0011] In one possible implementation of this application, the fluid assembly includes an extension and a connector, both extending axially along the conduit. The proximal end of the connector is sealed to the distal end of the extension. Both the extension and the connector have fluid channels, and the conduit wall has a filling hole. The fluid channels and the expansion chamber are connected through the filling hole. The hardness of the extension is greater than that of the connector.

[0012] In one possible implementation of this application, the distal portion of the extension is an insertion section, and the proximal portion of the extension is an extension section. The extension section is used to connect with the conveying device. The connector is sleeved with the insertion section, and both the insertion section and the connector are sealed to the pipe wall of the conduit.

[0013] In one possible implementation of this application, the cross-sections of both the insertion segment and the connector are flat annular, the length of the short axis of the flat annular is less than the length of the long axis of the flat annular, and the length of the long axis is greater than the thickness of the conduit wall. The extension direction of the long axis points to the circumference of the conduit, and the short axis is parallel to the radial direction of the conduit.

[0014] In one possible implementation of this application, the length of the minor axis is less than or equal to 0.15 mm; and / or, the length of the major axis is less than or equal to 0.6 mm.

[0015] In one possible implementation of this application, the outer diameter of the extension section is greater than the outer diameter of the insertion section; and / or, the outer diameter of the extension section is greater than or equal to 0.5 mm, and the outer diameter of the insertion section is less than or equal to 0.4 mm.

[0016] In one possible implementation of this application, the proximal end of the connector is fitted onto the distal end of the extension and is bonded to the distal end of the extension.

[0017] On the other hand, this application provides a suction system, which includes: a guide tube, a delivery device, a suction device, and a suction conduit provided by any one of the above. The guide tube has a guide channel, the inner diameter of which is larger than the outer diameter of the conduit. The delivery device is connected to a fluid assembly, and fills the expansion chamber with fluid through the fluid assembly, enabling the expansion member to fill the gap between the conduit and the guide tube. The suction channel communicates with the guide channel, and the suction device suctions the clumps at the distal end of the conduit through the suction channel and the guide channel.

[0018] The suction system provided in this application includes the suction conduit provided by any of the above-mentioned methods. Therefore, the suction conduit can maintain a small outer diameter, which is beneficial to make full use of the larger lumen of the guide tube to increase the suction flow rate and suction force. Attached Figure Description

[0019] Figure 1 A schematic diagram of the suction system provided in this application;

[0020] Figure 2 This is a schematic diagram of the aspiration catheter provided in this application;

[0021] Figure 3 Provided for this application Figure 2 An enlarged schematic diagram of part A in the middle;

[0022] Figure 4This is a schematic diagram of the catheter components in the aspiration catheter provided in this application;

[0023] Figure 5 This is a schematic diagram of the structure of the adjustment layer of the catheter component in the aspiration catheter provided in this application;

[0024] Figure 6 Provided for this application Figure 3 A schematic diagram of the cross-sectional structure along the BB direction;

[0025] Figure 7 Provided for this application Figure 3 A schematic diagram of the cross-sectional structure along the CC direction;

[0026] Figure 8 A cross-sectional view of the extension in the suction catheter provided in this application;

[0027] Figure 9 Provided for this application Figure 8 A schematic diagram of the cross-sectional structure along the DD direction.

[0028] Explanation of reference numerals in the attached figures:

[0029] 1-Conduit fitting; 11-Anti-blocking layer; 12-Retaining layer; 13-Adjusting layer; 131-First adjusting section; 132-Second adjusting section; 133-Third adjusting section; 134-Fourth adjusting section; 135-Fifth adjusting section; 136-Sixth adjusting section; 14-Suction flow channel; 2-Expansion component; 21-Expansion chamber; 3-Fluid assembly; 31-Extension component; 311-Insert section; 312-Extension section; 32-Connector; 33-Filling hole; 34-Adhesive layer; 35-Fluid channel; 36-Long axis; 37-Short axis; 4-Developing component; 5-Guiding tube; 51-Guiding channel; 6-Connecting seat; 7-Connecting valve; 71-Side branch passage; Y-Radial; Z-Axial. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the specific technical solutions of this application will be further described in detail below with reference to the accompanying drawings of the embodiments of this application. The following embodiments are used to illustrate this application, but are not intended to limit the scope of this application.

[0031] In the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more.

[0032] Furthermore, in the embodiments of this application, directional terms such as "upper," "lower," "left," and "right" are defined relative to the positions in which the components are schematically placed in the accompanying drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and can change accordingly depending on the position of the components in the accompanying drawings.

[0033] In the embodiments of this application, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium.

[0034] In embodiments of this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0035] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0036] Endovascular treatment for acute ischemic stroke includes removing thrombi from blood vessels using a suction catheter, particularly for highly tortuous and narrowed blood vessels such as those in the brain. Removing thrombi from blood vessels using a suction catheter has shown good therapeutic effects.

[0037] In complex vascular environments, the applicability of aspiration catheters provided by related technologies has significant limitations. Due to the small size and complex anatomical structure of the intracranial vessels that need to be accessed, the size of the aspiration catheter is restricted, resulting in a smaller diameter at the distal end. While a smaller diameter facilitates access to intracranial vessels, it also limits the ability to provide effective suction force. Although some aspiration catheters employ a structure with a larger lumen proximally and a smaller lumen distally, the proximal inner and outer diameters of such catheters are still smaller than the lumen of the guiding catheter due to limitations in the guiding catheter's inner diameter.

[0038] This application provides a suction catheter that maintains a small outer diameter, which facilitates full utilization of the larger lumen of the catheter to increase suction flow rate and suction force. (See also...) Figure 1 , Figure 2 and Figure 3 , Figure 1 This is a schematic diagram of the suction system provided in this application. Figure 2 This is a schematic diagram of the aspiration catheter provided in this application. Figure 3 Provided for this application Figure 2 An enlarged schematic diagram of part A in the middle.

[0039] The aspiration catheter provided in this embodiment includes: a catheter component 1, an expansion component 2, a fluid assembly 3, and a imaging component 4; wherein, the catheter component 1 has an aspiration channel 14; the expansion component 2 is disposed on the outer wall of the proximal end of the catheter component 1, and the expansion component 2 is sealed to the outer wall of the catheter component 1 to form an expansion cavity 21, and the expansion component 2 is elastic; the fluid assembly 3 is connected to the wall of the catheter component 1, and the fluid assembly 3 extends to a position corresponding to the expansion cavity 21, and the fluid assembly 3 has a fluid channel 35, which communicates with the expansion cavity 21; the imaging component 4 is disposed on the distal end of the catheter component 1, and the imaging component 4 is used to display the position of the distal end of the catheter component 1.

[0040] In this embodiment, the guiding tube 5 can be inserted into the body, and the catheter 1 can be inserted into a blood vessel within the body along the inner lumen of the guiding tube 5 to aspirate blood from the blood vessel, thereby removing thrombi and other substances from the blood vessel to the outside. For example, the catheter 1 can be configured as a cylindrical elongated tubular structure, with the cavity inside the tubular catheter 1 serving as the aspiration channel 14. By aspirating through the aspiration channel 14, a negative pressure can be formed within the aspiration channel 14.

[0041] It should be noted that in this application, "distal" and "proximal" refer to the extension direction along the Z-axis of the catheter element 1. The distal end is the end of the aspiration catheter furthest from the operator, meaning it is the end that first enters or is closest to the body. The proximal end is the end of the aspiration catheter closest to the operator, meaning it is the end that last enters or is furthest from the body. For example, as... Figure 2 As shown, the far end is Figure 2 The right side of the middle, the proximal end is Figure 2 Left side of the middle.

[0042] In this embodiment of the application, after the guiding tube 5 and the catheter 1 are inserted into the blood vessel, there is a gap between the catheter 1 and the guiding tube 5. An expansion member 2 can be provided on the catheter 1 to fill and seal the gap between the catheter 1 and the guiding tube 5, thereby creating a sealed environment between the catheter 1 and the blood vessel, so that a large negative pressure can be formed in the aspiration channel 14.

[0043] For example, such as Figure 3 As shown, an expansion member 2 can be provided at either the proximal or distal end of the conduit 1. The expansion member 2 can be made of a compliant or semi-compliant material to facilitate elastic deformation. For example, it can be made of thermoplastic polyurethane elastomer (TPU) or silicone. The expansion member 2 can be configured as an annular sheet structure, fitted onto the outer wall of the conduit 1, with both edges of the expansion member 2 sealed to the outer wall of the conduit 1. For example, the expansion member 2 can be sealed to the conduit 1 using laser welding or adhesive bonding. Thus, an expansion cavity 21 can be formed on the outer wall of the conduit 1 by the expansion member 2. By supplying fluids such as gas or liquid into the expansion cavity 21, the volume of the expansion member 2 can be changed, thereby sealing the gap between the conduit 1 and the guide tube 5.

[0044] In this embodiment of the application, fluid can be delivered into the expansion cavity 21 through the fluid assembly 3. For example, the fluid assembly 3 can be configured as a tubular structure so that the fluid assembly 3 has a cavity that serves as a fluid channel 35.

[0045] For example, such as Figure 2 and Figure 3 As shown, a portion of the fluid assembly 3 can be fixed to the wall of the conduit 1, and the portion of the fluid assembly 3 fixed to the wall of the conduit 1 extends along the axial direction Z of the conduit 1. For example, a groove formed by a radial indentation Y along the conduit 1 can be provided on the wall of the proximal end of the conduit 1. This groove matches the fluid assembly 3, so that the fluid assembly 3 as a whole, or a portion of the fluid assembly 3 along the radial direction Y, can be embedded into the groove at the proximal end of the conduit 1, such as sealing the fluid assembly 3 to the conduit wall by means of bonding, laser welding, etc.

[0046] In another example, the fluid assembly 3 can be extended within the pipe wall to a position corresponding to the expansion member 2. For instance, the groove on the pipe wall can be extended into the expansion cavity 21, and the edge of the expansion member 2 adjacent to the fluid assembly 3 can be sealed and connected by bonding, laser welding, thermal bonding, or other processes. This would allow the distal end of the fluid assembly 3 to extend into the expansion cavity 21, thus connecting the fluid channel 35 and the expansion cavity 21.

[0047] In another example, a blind hole can be provided in the wall of the proximal end of the conduit 1, which matches the distal portion of the fluid assembly 3. The distal portion of the fluid assembly 3 can be inserted into the blind hole and sealed to the wall, so that the portion of the fluid assembly 3 connected to the wall of the conduit 1 extends along the axial direction Z of the conduit 1 within the wall.

[0048] In this embodiment, a radiopaque element 4 can be disposed at the distal end of the catheter 1. For example, the radiopaque element 4 can be made of an X-ray-impermeable material, such as a platinum-tungsten alloy, tantalum, or gold. The radiopaque element 4 can be configured as a semi-circular or complete ring and can be embedded within the distal end of the catheter 1. For example, the distance between the distal end of the radiopaque element 4 and the distal end of the catheter 1 can be 0.5 mm. Therefore, after the catheter 1 is inserted into the body, the position of the distal end of the catheter 1 within the body can be quickly determined using the radiopaque element 4.

[0049] The aspiration catheter provided in this embodiment has an expansion member 2 on its outer wall. By delivering fluid into the expansion cavity 21 formed by the expansion member 2 and the catheter 1, the volume of the expansion member 2 can be changed. This allows the expansion member 2 to fill the gap between the catheter 1 and the guiding tube 5, facilitating the generation of a higher negative pressure within the catheter 1 during aspiration of the guiding tube 5. Furthermore, a contrast agent 4 is provided at the distal end of the catheter 1, allowing for real-time and rapid determination of the distal end of the catheter 1 within the blood vessel, facilitating physician confirmation of whether the distal end of the catheter 1 is close to a thrombus. Simultaneously, by connecting the fluid assembly 3 to the wall of the catheter 1 and extending the fluid assembly 3 to a position corresponding to the expansion cavity 21, fluid can be delivered into the expansion cavity 21 through the fluid channel 35 of the fluid assembly 3. This structural design allows the wall of the conduit 1 to provide an installation position for the fluid assembly 3, without requiring the fluid assembly 3 to be attached to the inner or outer wall of the conduit 1. This prevents the fluid assembly 3 from protruding completely from the outer wall of the conduit 1, thus eliminating the need to change the overall radial dimension of the suction conduit. Consequently, the suction conduit can maintain a smaller outer diameter, which is beneficial for fully utilizing the larger lumen of the guide tube 5 to increase the suction flow rate and suction force.

[0050] In some possible embodiments of this application, reference is made to Figure 4 and Figure 5 , Figure 4 This is a schematic diagram of the catheter components in the aspiration catheter provided in this application. Figure 5 This is a schematic diagram of the structure of the adjustment layer of the suction catheter provided in this application. The catheter 1 includes a barrier layer 11, a retaining layer 12 and an adjustment layer 13. The barrier layer 11 encloses and forms a suction channel 14. The retaining layer 12 covers the barrier layer 11 to restrict the movement of the barrier layer 11 in the radial direction Y. The adjustment layer 13 covers the retaining layer 12.

[0051] In this embodiment, the catheter 1 can be configured as a slender cylindrical shape, and from the inside out, the catheter 1 can include a barrier layer 11, a retaining layer 12, and an adjusting layer 13. The barrier layer 11 reduces the resistance to flow of thrombi, etc.; the retaining layer 12 provides sufficient strength to maintain a stable structural shape; and the adjusting layer 13 provides high toughness and adjusts the hardness of different parts of the catheter 1. For example, the length of the catheter 1 can be set to 250 mm to 450 mm.

[0052] For example, the barrier layer 11 can be made of a material with a low coefficient of friction. For instance, the barrier layer 11 can be made of polytetrafluoroethylene (PTFE), high-density polyethylene (HDPE), etc., and the barrier layer 11 can be set as a cylinder with an inner diameter of 1.04 mm to 2.24 mm.

[0053] In another example, the retaining layer 12 may be made of a material with a strength greater than that of at least one of the regulating layer 13 and the blocking layer 11. For example, the retaining layer 12 may be made of metallic materials such as 304 stainless steel, nickel-titanium alloy, or platinum-tungsten alloy. Figure 4 As shown, the retaining layer 12 can be configured as a helical spring structure, such as using 304 stainless steel wire to wind the retaining layer 12. The diameter of the 304 stainless steel wire can be 0.05 mm, and the pitch of the wound stainless steel helical spring can be 0.09 mm. The distal end of the stainless steel helical spring can be fixed by laser welding. The developing element 4 can be welded and fixed to the stainless steel helical spring. Alternatively, the retaining layer 12 can be configured as a metal braided structure. The retaining layer 12 made of metal material can be used as the developing element 4. The specific structure of the retaining layer 12 is not limited in the embodiments of this application.

[0054] As another example, the conditioning layer 13 can be made of a material with high toughness and elasticity. For example, the conditioning layer 13 can be made of polymers, such as polyether block polyamide (PEBAX), nylon, polyurethane elastomer (TPU), etc.

[0055] Another example, such as Figure 5As shown, the regulating layer 13 can be configured with at least two regulating sections, which are sequentially distributed along the axial direction Z of the conduit 1. The hardness of the at least two regulating sections decreases sequentially from the proximal end to the distal end of the conduit 1. That is, different regulating sections can use different polymers to make the hardness of the regulating layer 13 gradually decrease from the proximal end to the distal end. For example, the inner diameter of the barrier layer 11 can be set to 1.78 mm, the outer diameter of the regulating layer 13 can be set to 2.17 mm, the wall thickness of the conduit 1 can be 0.39 mm, the length of the conduit 1 can be 420 mm, and the total length of the suction conduit can be 1500 mm, meaning the length of the extension section 312 of the fluid assembly 3 is approximately 1080 mm.

[0056] For example, the adjustment layer 13 can be configured to include a structure with six adjustment segments from the proximal end to the distal end of the catheter 1. The six adjustment segments are made of nylon 12, pebax 6333, pebax 5533, pebax 4033, pebax 3533, and TPU 80A, respectively. Specifically, the first adjustment section 131 is made of nylon 12, with a length of 150 mm and a Shore hardness of 70D to 80D; the second adjustment section 132 is made of Pebax 6333, with a length of 20 mm and a Shore hardness of 62D to 65D; the third adjustment section 133 is made of Pebax 5533, with a length of 20 mm and a Shore hardness of 52D to 56D; the fourth adjustment section 134 is made of Pebax 4033, with a length of 20 mm and a Shore hardness of 39D to 43D; the fifth adjustment section 135 is made of Pebax 3533, with a length of 20 mm and a Shore hardness of 30D to 34D; and the sixth adjustment section 136 is made of TPU 80A, with a length of 20 mm and a Shore hardness of 18D to 23D. Therefore, the total length of the adjustment layer 13 is 420 mm. This allows the distance between the distal end of the imaging element 4 and the distal end of the catheter element 1 to be 0.5 mm.

[0057] This allows the proximal end of the adjustment layer 13 to have higher rigidity, providing stronger support for the catheter 1 and making it easier to maintain its shape, thus facilitating the application of pushing force to the catheter 1. Conversely, the distal end of the adjustment layer 13 can have lower rigidity, making the distal end of the catheter 1 more flexible and allowing it to bend and deform easily, facilitating its insertion into blood vessels.

[0058] It should be noted that the hardness and length measurements of all the above adjustment sections were conducted at normal temperature and pressure (20℃, one standard atmosphere). A type D Shore hardness tester can be used to measure the hardness, and a millimeter measuring tape can be used to measure the length.

[0059] In the above embodiments, since the catheter 1 includes an adjustment layer 13, a retaining layer 12, and an anti-blocking layer 11, by selecting the materials of the adjustment layer 13, the retaining layer 12, and the anti-blocking layer 11, the fluid such as thrombus can have good fluidity in the catheter 1, the distal end of the catheter 1 can have low hardness to facilitate intervention in tortuous blood vessels, the proximal end of the catheter 1 can have good bending and folding resistance to facilitate the application of pushing force to the catheter 1, and the catheter 1 can have high strength to resist the negative pressure force during aspiration and keep the aspiration channel 14 unobstructed.

[0060] In some possible embodiments of this application, reference is made to Figure 6 , Figure 7 , Figure 8 and Figure 9 , Figure 6 Provided for this application Figure 3 A schematic diagram of the cross-sectional structure along the BB direction. Figure 7 Provided for this application Figure 3 A cross-sectional view of the structure along the CC direction. Figure 8 This is a cross-sectional structural diagram of the extension component in the suction catheter provided in this application. Figure 9 Provided for this application Figure 8 A schematic diagram of the cross-sectional structure along the DD direction.

[0061] like Figure 2 and Figure 3 As shown, the fluid assembly 3 includes an extension 31 and a connector 32. Both the extension 31 and the connector 32 extend along the axial direction Z of the conduit 1. The proximal end of the connector 32 is sealed to the distal end of the extension 31. Both the extension 31 and the connector 32 have fluid channels 35 and filling holes 33 on the pipe wall. The fluid channels 35 and the expansion chamber 21 are connected through the filling holes 33. The hardness of the extension 31 is greater than that of the connector 32.

[0062] In this embodiment, the fluid assembly 3 can be configured to include an extension member 31 and a connector 32, that is, the fluid assembly 3 is formed by connecting the extension member 31 and the connector 32.

[0063] For example, such as Figure 8 As shown, the extension member 31 can be made of metal materials, such as 304 stainless steel or nickel-titanium alloy. The extension member 31 can be set as a slender sodium thiosulfate tube and the sodium thiosulfate tube can be set as a variable diameter cylindrical structure, that is, the surface of the sodium thiosulfate tube has micro-engineering characteristics. For example, specific grooves or spiral patterns can be set on the surface of the sodium thiosulfate tube to enhance the flexibility of the sodium thiosulfate tube and the efficiency of pushing force transmission.

[0064] In another example, along the axial direction of the extension member 31, the extension member 31 can be configured with different pipe diameters. For example, the distal end of the extension member 31 can be configured as a cylindrical shape with a smaller outer diameter, and the proximal end of the extension member 31 can be configured as a cylindrical shape with a larger outer diameter. The portion of the extension member 31 with a smaller outer diameter can be used as the insertion section 311, and the portion of the extension member 31 with a larger outer diameter can be used as the extension section 312. The length of the extension section 312 can be greater than the length of the guide tube 5, so that after the extension section 312 passes through the guide tube 5, the proximal end of the extension section 312 can be located outside the proximal end of the guide tube 5. For example, a connecting seat 6 for connection to a pressure source can be provided at the proximal end of the extension section 312. The pressure source can be a delivery device such as a syringe or a pump. The connecting seat 6 can be a device that facilitates sealing and insertion, such as a needle seat that matches the syringe barrel, so as to facilitate the connection of the syringe barrel tip to the needle seat. Air or liquid can be filled into the expansion chamber 21 by the syringe.

[0065] Another example, such as Figure 3 As shown, the connector 32 can be made of a material with lower hardness than the extension 31. For example, the connector 32 can be made of a polymer material and formed into a thin film, such as polyimide (PI). The PI can be made into a cylinder that matches the insertion section 311 of the extension 31. For example, the PI can be made into a cylindrical PI tube with an outer diameter of 0.6 mm and an inner diameter of 0.5 mm, and then the cylindrical PI tube can be sealed and connected to the distal end of the insertion section 311 of the extension 31.

[0066] Another example, such as Figure 3 and Figure 6 As shown, the proximal end of the connector 32 can be fitted onto the distal end of the insertion segment 311 of the extension 31. For example, the connector 32 can be fixed and sealed to the distal end of the insertion segment 311 by adhesive bonding. Adhesive can be applied to the outer wall of the distal end of the insertion segment 311, and then the connector 32 can be fitted onto the distal end of the insertion segment 311. After the adhesive cures, an adhesive layer 34 is formed.

[0067] Thus, as Figure 3 As shown, at least a portion of the insertion section 311 and the connector 32 can be inserted into the wall of the proximal end of the conduit 1. For example, a blind hole extending along the axial direction Z of the conduit 1 can be provided on the wall of the proximal end of the conduit 1. This blind hole matches both the insertion section 311 and the connector 32. The insertion section 311 and the connector 32 can then be inserted into the blind hole on the wall from the end face of the proximal end of the conduit 1. The insertion section 311 can be sealed to the wall by means of bonding, laser welding, etc., and the connector 32 can be sealed to the wall by means of bonding, laser welding, etc., thereby allowing the distal portion of the fluid assembly 3 to be inserted into the wall of the conduit 1 along the axial direction Z of the conduit 1.

[0068] Another example, such as Figure 3 As shown, the blind hole on the pipe wall can be extended to the location of the expansion cavity 21, thus allowing a filling hole 33 to be provided on the pipe wall. The filling hole 33 can be located on the outer wall at the distal end of the blind hole. When the connector 32 is inserted into the bottom of the blind hole, a filling hole 33 can also be provided on the connector 32. The filling hole 33 on the pipe wall and the filling hole 33 on the insertion section 311 coincide along the radial Y direction of the conduit 1. This allows the fluid channel 35 and the expansion cavity 21 to be connected through the filling hole 33.

[0069] In the above embodiments, since the fluid assembly 3 includes an extension 31 and a connector 32, the extension section 312 of the fluid assembly 3 can have high strength by selecting the materials of the extension 31 and the connector 32, and it is convenient to seal the connector 32 located at the distal end of the fluid assembly 3 to the conduit 1. Furthermore, by inserting at least a portion of the insertion section 311 and the connector 32 along the axial direction Z of the conduit 1 into the wall of the conduit 1, the wall can be used to provide space for the insertion section 311 and the connector 32 to be accommodated and installed. This allows the insertion section 311 and the connector 32 connected to the wall of the conduit 1 to be completely hidden inside the wall of the conduit 1, thereby minimizing the space occupied by the insertion section 311 and the connector 32 inside or outside the wall. Consequently, the radial dimension of the suction conduit (since the volume of the expansion member 2 can vary, the radial dimension of the expansion member 2 is ignored here) can be the same as the radial dimension of the conduit 1. In this way, with the inner diameter of the guide tube 5 fixed, it is advantageous to have a larger inner diameter for the guide tube 1, which in turn allows the suction tube to have a larger suction flow channel 14, which is beneficial to generate a larger suction negative pressure in the suction tube.

[0070] In some possible embodiments of this application, such as Figure 6 , Figure 7 , Figure 8 and Figure 9 As shown, the cross-sections of the insertion section 311 and the connector 32 are both flat annular. The length of the short axis 37 of the flat annular ring is less than the length of the long axis 36 of the flat annular ring, and the length of the long axis 36 is greater than the thickness of the tube wall of the conduit 1. The extension direction of the long axis 36 points to the circumference of the conduit 1, and the short axis 37 is parallel to the radial direction Y of the conduit 1.

[0071] In this embodiment, the portion of the insertion segment 311 that is inserted into the wall of the conduit 1 can be set as a flat cylindrical shape, or the entire insertion segment 311 can be set as a flat cylindrical shape. At the same time, the connector 32 is also set as a flat cylindrical shape, that is, the cross-section of the portion of the insertion segment 311 that is inserted into the wall of the conduit 1 and the connector 32 are both approximately elliptical.

[0072] For example, the fluid assembly 3 can be initially configured as a cylinder, and the distal end of the fluid assembly 3 can be stamped into a flat annular shape by stamping, that is, at least a portion of the insertion section 311 can be stamped into a flat cylindrical shape with a flat annular cross-section. Figure 6 and Figure 7 As shown, a flattened annulus can be understood as an annulus formed by two arc-shaped segments and two straight-edge segments. Both arc-shaped segments can be semicircular arcs. One straight-edge segment connects the corresponding sides of the two semicircular arcs, and the other straight-edge segment connects the other corresponding sides of the two semicircular arcs, thus forming a flattened cylindrical shape. Therefore, the major axis 36 of the cross-section of the flattened annulus includes the length of the straight-edge segment and the radii of the two semicircular arcs, while the minor axis 37 of the cross-section includes the radius of the semicircular arcs.

[0073] Another example, such as Figure 7 As shown, when the flat cylindrical insertion section 311 and connector 32 are inserted into the wall of the conduit 1, the short axis 37 of the flat cylindrical insertion section 311 and connector 32 can be made parallel or nearly parallel to the radial direction Y of the cylindrical conduit 1, while the long axis 36 of the flat cylindrical insertion section 311 and connector 32 can be perpendicular or nearly perpendicular to the radial direction Y of the cylindrical conduit 1. This allows the long axis 36 of the flat cylindrical insertion section 311 and connector 32 to extend circumferentially along the conduit 1, meaning the long axis 36 of the insertion section 311 and connector 32 can be considered as a chord of the circular cross-section of the conduit 1.

[0074] Another example, such as Figure 7 and Figure 9As shown, the length of the short axis 37 of the flat cylindrical insertion section 311 and the connector 32 can be set to be less than or equal to 0.15 mm; and / or, the length of the long axis 36 of the flat cylindrical insertion section 311 and the connector 32 can be set to be less than or equal to 0.6 mm. For example, when the wall thickness of the conduit 1 is close to 0.4 mm and the outer diameter of the conduit 1 is close to 2 mm, the length of the short axis 37 of the flat cylindrical insertion section 311 and the connector 32 can be set to 0.15 mm, 0.13 mm, 0.11 mm, etc., so that the length of the short axis 37 of the flat cylindrical insertion section 311 and the connector 32 is less than one-third of the wall thickness of the conduit 1. The length of the long axis 36 of the flat cylindrical insertion section 311 and the connector 32 can be set to 0.6 mm, 0.5 mm, 0.4 mm, etc., so that the length of the long axis 36 of the flat cylindrical insertion section 311 and the connector 32 is less than 0.6 mm but greater than the wall thickness of the conduit 1. The wall thickness of the flat cylindrical insertion section 311 and the connector 32 can be set to 0.025mm, 0.023mm, or 0.02mm, etc. This way, after the flat cylindrical insertion section 311 and the connector 32 are placed inside the tube wall of the conduit 1, the portion of the tube wall surrounding the flat cylindrical insertion section 311 and the connector 32 can have sufficient thickness. This ensures that the strength and other properties of the conduit 1 meet the usage requirements, thus improving the reliability of the suction conduit.

[0075] In the above embodiments, since the portion connecting the insertion section 311, the connector 32, and the conduit 1 is configured as a flat cylindrical shape with a flat annular cross-section, and the short axis 37 of the flat annular shape is parallel to the radial direction Y of the conduit 1, the long axis 36 of the flat cylindrical insertion section 311 and the connector 32 can extend circumferentially along the conduit 1 within the conduit wall. This reduces the installation space occupied by the flat cylindrical insertion section 311 and the connector 32 along the radial direction Y of the conduit 1. Not only can the conduit 1 maintain a smaller wall thickness, but the insertion section 311 and the connector 32 can also have a larger cross-sectional area. Consequently, the fluid channel 35 of the fluid assembly 3 can have a larger flow area, facilitating the delivery of fluid to the expansion chamber 21.

[0076] In some possible embodiments of this application, such as Figure 8 As shown, the outer diameter of the extension section 312 is greater than the outer diameter of the insertion section 311; and / or, the outer diameter of the extension section 312 is greater than or equal to 0.5 mm, and the outer diameter of the insertion section 311 is less than or equal to 0.4 mm.

[0077] In this embodiment, the fluid assembly 3 can be configured to include at least two sections with different diameters. For example, the entire extension section 312 can be configured as a long, thin cylinder with a larger outer diameter, while the end of the insertion section 311 connected to the extension section 312 (the proximal end of the insertion section 311) can be configured as a cylinder with a smaller outer diameter, and the end of the insertion section 311 away from the extension section 312 (the distal end of the insertion section 311) can be configured as a flattened cylinder with a smaller outer diameter. That is, the outer diameter of the extension section 312 is larger than the outer diameter of the insertion section 311, and the wall thickness of the extension section 312 and the wall thickness of the insertion section 311 can be the same or different. For example, the wall thickness of the extension section 312 can be set to be greater than the wall thickness of the insertion section 311.

[0078] For example, the outer diameter of the extension section 312 can be set to 0.5mm, 0.7mm, 0.8mm, 0.9mm, or 1mm, etc., wherein the outer diameter of the extension section 312 needs to be smaller than the inner diameter of the inner cavity of the guide tube 5, and the outer diameter of the extension section 312 can be less than or equal to half of the inner diameter of the inner cavity of the guide tube 5. For example, the outer diameter of the extension section 312 can be set to 0.5mm, the inner diameter of the extension section 312 can be set to 0.3mm, and the wall thickness of the extension section 312 can be 0.1mm.

[0079] In another example, the outer diameter of the cylindrical portion of the insertion segment 311 can be set to 0.4 mm, 0.38 mm, 0.35 mm, 0.3 mm, 0.28 mm, or 0.25 mm, etc., wherein the outer diameter of the cylindrical portion of the insertion segment 311 needs to be larger than the minor axis 37 of the flat cylindrical portion of the insertion segment 311. For example, the outer diameter of the cylindrical portion of the insertion segment 311 can be set to 0.4 mm, and the inner diameter of the cylindrical portion of the insertion segment 311 can be set to 0.3 mm, so that the wall thickness of the cylindrical portion of the insertion segment 311 is 0.05 mm.

[0080] In another example, the short axis 37 of the flat cylindrical portion of the insertion segment 311 can be set to 0.15 mm, the long axis 36 of the flat cylindrical portion of the insertion segment 311 can be set to 0.6 mm, and the wall thickness of the flat cylindrical portion of the insertion segment 311 can be set to 0.025 mm. The cylindrical portion of the insertion segment 311 and the extension segment 312 can be connected by a frustum-shaped annular connection. The distal end of the insertion segment 311 can be stamped into a flat annular shape by stamping, and the wall thickness of the flat annular portion can be reduced by stamping.

[0081] In the above embodiments, since the outer diameter of the extension section 312 is larger than that of the insertion section 311, the wall thickness of the extension section 312 can be greater than that of the insertion section 311. This allows the extension section 312 to have higher strength, which helps reduce the risk of damage to the extension section 312 when it is connected to the pressure source. Conversely, the smaller outer diameter of the insertion section 311 allows for a larger fluid channel 35 by reducing its wall thickness. Furthermore, the insertion section 311 is inserted and fixed within the wall of the conduit 1, which further reduces the risk of damage to the insertion section 311.

[0082] In addition, embodiments of this application also provide a suction system, such as Figure 1 As shown, the suction system includes: a guide tube 5, a delivery device, a suction device, and a suction conduit provided in any of the above embodiments. The guide tube 5 has a guide channel 51, the inner diameter of which is larger than the outer diameter of the conduit 1. The delivery device is connected to a fluid assembly 3, and fills the expansion chamber 21 with fluid through the fluid assembly 3, enabling the expansion member 2 to fill the gap between the conduit 1 and the guide tube 5. The suction channel 14 communicates with the guide channel 51, and the suction device suctions the clumps at the distal end of the conduit 1 through the suction channel 14 and the guide channel 51.

[0083] In this embodiment, the guide tube 5 is used to guide the aspiration catheter into the body. For example, the guide tube 5 can be configured as a cylindrical shape with a lumen, and the lumen of the guide tube 5 serves as a guide channel 51 for inserting the catheter component 1, such as setting the inner diameter of the lumen of the guide tube 5 to 2.23 mm. The proximal end of the fluid assembly 3 can be inserted through the proximal end of the guide tube 5.

[0084] like Figure 1 As shown, when the expansion member 2 is not filled, the suction conduit can slide in the guide channel 51 along the axial direction Z; when the expansion member 2 is filled, the expansion member 2 expands and abuts against the inner wall of the guide tube 5 to block the gap between the outer wall of the conduit member 1 and the inner wall of the guide tube 5, so that the suction flow channel 14 can be connected with the guide channel 51.

[0085] For example, a connecting valve 7 can be installed at the proximal end of the guiding tube 5. The connecting valve 7 has a side passage 71, which is connected to the guiding channel 51 of the guiding tube 5 and thus communicates with the suction channel 14 of the catheter fitting 1. A one-way valve can be installed in the side passage 71, which is open from the suction channel 14 to the side passage 71, but normally closed from the side passage 71 to the suction channel 14. Alternatively, the side passage 71 can be connected to a heparin cap to prevent the filled medium from flowing out of the side passage 71, thus preventing backflow.

[0086] Thus, when using this aspiration system, the distal end of the guiding catheter 5 can be inserted into a blood vessel in the body first, and then the catheter 1 can be inserted into the blood vessel along the guiding channel 51 of the guiding catheter 5 until the distal end of the catheter 1 reaches the location of the thrombus. Then, the proximal end of the guiding catheter 5 is sealed, and the delivery device (e.g., a syringe) is connected to the fluid assembly 3 to deliver fluid into the expansion member 2, causing the expansion member 2 to expand and fill the gap between the catheter 1 and the guiding catheter 5. For a heparin cap configuration, a needle syringe can be inserted into the heparin cap to deliver fluid, causing the expansion member 2 to expand. For a one-way valve configuration, a syringe with a Luer connector can be connected to the one-way valve to deliver fluid, causing the expansion member 2 to expand. Finally, negative pressure is provided through the aspiration device (e.g., a syringe) connected to the side passage 71 of the guiding catheter 5 to aspirate the clot (e.g., thrombus, plaque fragments).

[0087] Table 1

[0088]

[0089] Another example, referring to Table 1, shows the test data of the suction force of the aspiration system using the aspiration catheter provided in the embodiments of this application and the aspiration system in related technologies. At room temperature and pressure (20°C, one standard atmosphere), a 60ml syringe was used to perform aspiration on the ACE68 thrombus aspiration catheter from Genesys Pharma, the Sofia6PLUS aspiration catheter from MicroVention, the Catalyst6 aspiration catheter from Stryker, and the aspiration catheter provided in the embodiments of this application, respectively, to create negative pressure within the aspiration catheter.

[0090] As shown in Table 1, the suction negative pressure of the suction system using the suction catheter provided in this application reaches 60.75 mmHg, while the suction negative pressure of the other three existing suction catheters is approximately 26 mmHg. The suction negative pressure of the suction system in this application is at least 2.3 times that of the other three existing suction catheters. With similar tip areas for the suction catheters (the other three existing suction catheters), the tip force of the suction catheter provided in this application reaches 51.2 g, while the tip force of the other three existing suction catheters is approximately 21 g. The tip force of the suction catheter provided in this application is at least 2.4 times that of the other three existing suction catheters. Therefore, when using the suction catheter provided in this application to aspirate clots in a patient's blood vessels, a greater suction force can be generated than that generated by suction catheters in related technologies.

[0091] The suction system provided in this application includes the suction conduit provided in any of the above embodiments. Therefore, the suction conduit can maintain a small outer diameter, which is beneficial to make full use of the larger lumen of the guide tube 5 to increase the suction flow rate and suction force.

[0092] This application provides a method for thrombus aspiration using the above-described aspiration system. The method includes: guiding the aspiration catheter using the guide tube 5, which extends percutaneously into the patient's blood vessel; expanding the guide tube 2 and abutting against the inner wall of the guide channel 51 while maintaining a sealing effect; applying suction through the guide channel 51 and the aspiration flow channel 14 to aspirate fluid outside the guide tube 5, thereby removing the clot from the blood vessel.

[0093] The above embodiments are merely illustrative of the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and all should be covered within the scope of the specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way.

Claims

1. A suction catheter, characterized in that, include: The conduit fitting has a suction channel; An expansion member is disposed on the outer wall of the proximal end of the conduit, the expansion member is sealed to the outer wall of the conduit and surrounds it to form an expansion cavity, and the expansion member is elastic; A fluid assembly is connected to the wall of the conduit and extends to a position corresponding to the expansion chamber. The fluid assembly has a fluid channel that communicates with the expansion chamber. A highlighting element is disposed on the distal portion of the catheter, and the highlighting element is used to display the position of the distal portion of the catheter.

2. The aspiration catheter according to claim 1, characterized in that, The conduit includes an anti-blocking layer, a retaining layer, and an adjusting layer. The anti-blocking layer encloses and forms the suction channel. The retaining layer covers the anti-blocking layer to restrict the radial movement of the anti-blocking layer. The adjusting layer covers the retaining layer.

3. The aspiration catheter according to claim 2, characterized in that, The strength of the retaining layer is greater than the strength of the regulating layer; and / or, the strength of the retaining layer is greater than the strength of the blocking layer.

4. The aspiration catheter according to claim 2, characterized in that, The adjustment layer includes at least two adjustment sections, which are sequentially distributed along the axial direction of the catheter. Among two adjacent adjustment sections, the adjustment section closer to the proximal end of the catheter has a greater hardness than the adjustment section farther from the proximal end of the catheter.

5. The aspiration catheter according to any one of claims 1 to 4, characterized in that, The portion of the fluid assembly that connects to the pipe wall extends axially within the pipe wall along the conduit.

6. The aspiration catheter according to any one of claims 1 to 4, characterized in that, The fluid assembly includes an extension and a connector, both of which extend axially along the conduit. The proximal end of the connector is sealed to the distal end of the extension. Both the extension and the connector have the fluid channel. The conduit wall has a filling hole, and the fluid channel and the expansion chamber are connected through the filling hole. The hardness of the extension is greater than that of the connector.

7. The aspiration catheter according to claim 6, characterized in that, The distal portion of the extension member is an insertion section, and the proximal portion of the extension member is an extension section. The extension section is used to connect with the conveying device. The connector is sleeved with the insertion section. Both the insertion section and the connector are sealed to the wall of the conduit.

8. The aspiration catheter according to claim 7, characterized in that, Both the insertion section and the connector have a flat annular cross-section. The length of the short axis of the flat annular section is less than the length of the long axis of the flat annular section, and the length of the long axis is greater than the thickness of the tube wall of the conduit. The extension direction of the long axis points to the circumference of the conduit, and the short axis is parallel to the radial direction of the conduit.

9. The aspiration catheter according to claim 8, characterized in that, The length of the short axis is less than or equal to 0.15 mm; and / or the length of the long axis is less than or equal to 0.6 mm.

10. The aspiration catheter according to claim 7, characterized in that, The outer diameter of the extension section is greater than the outer diameter of the insertion section; and / or, the outer diameter of the extension section is greater than or equal to 0.5 mm, and the outer diameter of the insertion section is less than or equal to 0.4 mm.

11. The aspiration catheter according to claim 6, characterized in that, The proximal end of the connector is fitted onto the distal end of the extension and is bonded to the distal end of the extension.

12. A suction system, characterized in that, include: Guide tube, delivery device, suction device and suction conduit as described in any one of claims 1 to 11; The guide tube has a guide channel, the inner diameter of which is larger than the outer diameter of the conduit; the delivery device is connected to the fluid assembly, and the delivery device fills the expansion chamber with fluid through the fluid assembly, enabling the expansion member to fill the gap between the conduit and the guide tube; the suction channel is connected to the guide channel, and the suction device suctions the clumps at the distal end of the conduit through the suction channel and the guide channel.

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