Thrombus aspiration catheter and catheter assembly

Abstract

This application provides a thrombus aspiration catheter and catheter assembly. The thrombus aspiration catheter includes: a tube body having an inner lumen with a first central axis; the inner lumen is divided into an aspiration chamber and a guidewire chamber that are not interconnected in a direction perpendicular to the first central axis; the guidewire chamber has a second central axis that is offset from the first central axis. The sidewall of the tube body is provided with multiple rows of holes spaced apart along the axial direction of the tube body. Each row of holes includes multiple side holes spaced apart along the circumference of the tube body. Each side hole communicates with the aspiration chamber, and the diameter of the multiple side holes increases with the vertical distance between the center of the multiple side holes and the second central axis. The thrombus aspiration catheter of this application embodiment can improve the stability of fluid flow within the tube body.

Description

Technical Field

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

[0002] Treatment (or adjunctive treatment) of vascular thrombosis often involves using catheters with aspiration capabilities (referred to as aspiration catheters). Aspiration catheters utilize pressure differentials, pumping (such as spiral pumps), or water jet effects to generate a suction force, drawing thrombi or thrombus fragments from the blood vessel into the catheter, which is then further removed from the body. The embolic material (and / or its fragments) must pass through aspiration ports on the catheter into the aspiration catheter.

[0003] Aspiration catheters have two types of aspiration ports: end ports and side ports. The end port is located at the front end of the catheter, while the side port is located on the lateral wall of the catheter. The side port of the aspiration catheter helps to increase the communication area between the catheter and the material to be aspirated in the blood vessel.

[0004] However, the side holes of existing suction cannulas have problems with uneven suction pressure and suction flow.

[0005] It should be noted that the above description of the background technology is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background technology section of this application. Summary of the Invention

[0006] This application provides a thrombus aspiration catheter and catheter assembly to solve at least one of the problems mentioned in the background art or other similar problems.

[0007] An embodiment of the first aspect of this application provides a thrombus aspiration catheter, comprising: a tube body having an inner lumen, the inner lumen having a first central axis, the inner lumen being divided into an aspiration lumen and a guidewire lumen that are not interconnected in a direction perpendicular to the first central axis, the guidewire lumen having a second central axis that is offset from the first central axis; wherein, the sidewall of the tube body is provided with multiple rows of holes arranged at intervals along the axial direction of the tube body, each row of holes including multiple side holes arranged at intervals along the circumference of the tube body, each side hole communicating with the aspiration lumen, and the diameter of the multiple side holes increasing with the increase of the vertical distance between the center of the multiple side holes and the second central axis.

[0008] In some embodiments, the diameter of each side hole is d, and the vertical distance from the center of each side hole to the second central axis is L, where d and L satisfy the following formula: Where c is a constant.

[0009] In some embodiments, the center of the side hole with the largest diameter in each row of holes is a first center, and a radial line passing through the first center and the first central axis intersects the second central axis.

[0010] In some embodiments, the side holes in each row of holes, except for the side hole with the largest diameter, are arranged symmetrically with respect to the radial line.

[0011] In some embodiments, the inner cavity is divided into the suction cavity and the guide wire cavity by a partition tube disposed within the tube body, and the partition tube is connected to the tube body.

[0012] In some embodiments, the separator tube is directly connected to the inner wall of the tube body.

[0013] In some embodiments, the separator tube and the tube body are an integral structure.

[0014] In some embodiments, the tube has a distal end, the distal end of which is provided with an end hole communicating with the suction chamber.

[0015] A second aspect of this application provides a thrombus aspiration catheter assembly, comprising: the thrombus aspiration catheter described in the first aspect embodiment; and a connecting tube for connecting the tube body of the thrombus aspiration catheter to a negative pressure aspiration device, wherein the inner diameter of the connecting tube is larger than the inner diameter of the lumen.

[0016] In some embodiments, the inner diameter of the connecting tube is not less than twice the inner diameter of the inner cavity.

[0017] The beneficial effects of the thrombus aspiration catheter and catheter assembly in the embodiments of this application include:

[0018] 1. The embodiments of this application, by setting up multiple rows of holes, with each row of holes having multiple side holes, can improve the overall aspiration rate and reduce the adverse effects of local side hole blockage on the thrombus aspiration effect.

[0019] 2. In this embodiment of the application, by setting the diameter of multiple side holes in each row of holes to be distributed in a circumferential gradient, the smoothness of fluid flow in the pipe can be effectively improved.

[0020] 3. In this embodiment of the application, by setting a connecting tube to connect the thrombus aspiration catheter and the negative pressure aspiration device, and setting the inner diameter of the connecting tube to be larger than the inner diameter of the tube body, it is possible to ensure that there is sufficient aspiration pressure in the aspiration chamber of the thrombus aspiration catheter, thereby improving the aspiration effect.

[0021] Specific embodiments of this application are disclosed in detail with reference to the following description and accompanying drawings, indicating how the principles of this application can be adopted. It should be understood that the embodiments of this application are not limited in scope. Within the spirit and scope of the appended claims, embodiments of this application include many changes, modifications, and equivalents. Attached Figure Description

[0022] The accompanying drawings, which form part of the specification, are used to provide a further understanding of the embodiments of this application and illustrate the implementation methods of this application, together with the textual description, to explain the principles of this application. Obviously, the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without creative effort. In the drawings:

[0023] Figure 1 This is a schematic diagram of a thrombus aspiration catheter according to an embodiment of this application;

[0024] Figure 2 yes Figure 1 A schematic diagram of the cross-section of a thrombus aspiration catheter;

[0025] Figure 3 This is a schematic diagram of the thrombus aspiration catheter assembly in an embodiment of this application.

[0026] Explanation of key component designations:

[0027] 100. Thrombus aspiration catheter;

[0028] 101. Pipe body;

[0029] 102. Internal cavity;

[0030] 103. Suction chamber;

[0031] 104. Guidewire lumen;

[0032] 105. Hole group;

[0033] 106. Side hole;

[0034] 107. End hole;

[0035] 108. Divider tube;

[0036] C1: First central axis;

[0037] C2: Second central axis;

[0038] C3: Radial line;

[0039] P1: First Center;

[0040] 200. Connecting pipe. Detailed Implementation

[0041] Referring to the accompanying drawings, the foregoing and other features of this application will become apparent from the following description. Specific embodiments of this application are specifically disclosed in the description and drawings, illustrating partial implementations in which the principles of this application may be adopted. It should be understood that this application is not limited to the described embodiments; rather, it includes all modifications, variations, and equivalents falling within the scope of the appended claims.

[0042] In the embodiments of this application, the terms "first," "second," etc., are used to distinguish different elements by their designation, but do not indicate the spatial arrangement or temporal order of these elements, and these elements should not be limited by these terms. The term "and / or" includes any one or more of the terms listed in association and all combinations thereof. The terms "comprising," "including," "having," etc., refer to the presence of the stated features, elements, components, or assemblies, but do not exclude the presence or addition of one or more other features, elements, components, or assemblies.

[0043] In the embodiments of this application, the singular forms "a," "the," etc., may include the plural forms and should be broadly understood as "a kind" or "a class" rather than limited to the meaning of "one." Furthermore, the term "the" should be understood to include both the singular and plural forms unless the context clearly indicates otherwise. Additionally, the term "multiple" means two or more, unless otherwise stated. The term "proximal" refers to the position on the device closest to the operator using the device (e.g., a doctor), while the term "distal" refers to the position on the device furthest from the operator.

[0044] The inventors discovered that existing suction catheters have uneven suction pressure and flow rate at their side holes.

[0045] To address the aforementioned problems, embodiments of the first aspect of this application propose a thrombus aspiration catheter that can improve the problem of uneven aspiration pressure and flow rate.

[0046] The thrombus aspiration catheter of this application will now be described with reference to the accompanying drawings.

[0047] Figure 1 This is a schematic diagram of a thrombus aspiration catheter 100 according to an embodiment of this application. Figure 2 yes Figure 1 A schematic diagram of the cross-section of the thrombus aspiration catheter 100.

[0048] like Figure 1 , Figure 2As shown, the thrombus aspiration catheter 100 provided in this embodiment includes a tube body 101, which has an inner lumen 102. The inner lumen 102 has a first central axis C1 and is cylindrical in this embodiment. The inner lumen 102 is divided into an aspiration chamber 103 and a guidewire chamber 104, which are not interconnected in a direction perpendicular to the first central axis C1. The aspiration chamber 103 is used to aspirate thrombi or thrombus fragments from the blood vessel, and the guidewire chamber 104 is for the guidewire to pass through. During actual surgical procedures, the distal end of the guidewire protrudes from the tube body 101 in the blood vessel to guide the movement of the thrombus aspiration catheter 100 within the blood vessel.

[0049] It can be understood that the inner cavity 102 has a dual-cavity structure. On the cross-section of the inner cavity 102 perpendicular to the first central axis C1, the suction cavity 103 and the guide wire cavity 104 are separated by the side wall of the guide wire cavity 104 and are not connected to each other. The suction cavity 103, the guide wire cavity 104 and the side wall of the guide wire cavity 104 occupy the entire cross-sectional area of ​​the inner cavity 102, so that the area of ​​the inner cavity 102 is allocated to the suction cavity 103 as much as possible, thereby maximizing the area of ​​the suction cavity 103 and improving the suction efficiency.

[0050] See Figure 2 The guide wire cavity 104 has a second central axis C2. In this embodiment, the guide wire cavity 104 is a cylindrical cavity. The second central axis C2 is offset from the first central axis C1. In other words, the guide wire cavity 104 is set off from the first central axis C1 of the tube body 101, which makes the suction cavity 103 an irregular cavity.

[0051] See Figure 1 , Figure 2 The tube body 101 has multiple rows of holes 105 arranged axially along the sidewall of the tube body 101. Each row of holes 105 includes multiple side holes 106 arranged circumferentially along the tube body 101. Each side hole 106 communicates with the aspiration chamber 103, and the thrombus enters the aspiration chamber 103 through each side hole 106. In this embodiment, by arranging multiple rows of holes 105 axially along the tube body 101 and multiple side holes 106 circumferentially along the tube body 101, compared with the traditional single side hole, a higher total aspiration rate, a larger total aspiration volume, and aspiration area can be provided, while reducing the adverse effects of local side hole 106 blockage on the thrombus aspiration effect. In addition, by setting the guidewire lumen 104 off-center from the tube body 101, it helps to reduce the adverse effects of the outer wall of the guidewire lumen 104 on the fluid entering the tube body 101 from the side holes 106, such as fluid impact on the outer wall of the guidewire lumen 104 causing flow turbulence. The farther the fluid inflow side hole 106 is from the guide wire cavity 104, the less adverse effects it is affected by the outer wall of the guide wire cavity 104.

[0052] See also Figure 2The diameters of the multiple side holes 106 in each row of holes 105 are distributed in a gradient along the circumference of the tube body 101. Specifically, the diameter of the multiple side holes 106 increases with the increase of the vertical distance between the center of the multiple side holes 106 and the second central axis C2. In other words, the side hole 106 farthest from the second central axis C2 (i.e., farthest from the sidewall of the guide wire cavity 104) has the largest diameter, and the side hole 106 closest to the second central axis C2 (i.e., closest to the sidewall of the guide wire cavity 104) has the smallest diameter. This can effectively adjust the pressure and flow distribution between the side holes, thereby improving the uniformity of the overall suction.

[0053] For ease of understanding, Figure 2 The principle of this application will be explained using the side hole 106 shown as an example.

[0054] like Figure 2 As shown, the side hole furthest from the second central axis C2 is the side hole 106 directly opposite the guide wire cavity 104 in the radial direction of the tube body 101. For ease of description, this side hole is referred to as the first side hole. The two side holes 106 located on opposite sides of the first side hole and adjacent to the first side hole are referred to as the second side holes. The two side holes 106 adjacent to the two second side holes 106 and close to the second central axis C2 are referred to as the third side holes. Figure 2 In the example, the distances of the two second side holes from the second central axis C2 are approximately equal, so the diameters of the two second side holes are also approximately equal. Similarly, the distances of the two third side holes from the second central axis C2 are approximately equal, so the diameters of the two third side holes are also approximately equal.

[0055] Because the diameters of the first, second, and third side holes are different, the suction flow rates in the first, second, and third side holes also differ during suction.

[0056] Now, let's explain the differences in aspiration flow rate among the different side holes, using a specific aspiration process as an example. Since the first side hole has the largest diameter, the aspirated blood and / or thrombus (referred to as fluid) preferentially flows into it, while very little fluid flows into the other side holes. Therefore, the fluid entering the tube 101 from the first side hole is largely unaffected by the impact or interference from fluids from other side holes and can flow relatively smoothly within the tube 101. When a large thrombus blocks the first side hole, the aspirated fluid can no longer flow into it and instead preferentially flows into the second side hole, whose diameter is only smaller than the first side hole. Similarly, the fluid entering the tube 101 from the second side hole is largely unaffected by the impact from fluids from other side holes and can flow relatively smoothly within the tube 101. When a large thrombus blocks the second side hole, the aspirated fluid can also no longer flow into it and instead preferentially flows into the third side hole, whose diameter is only smaller than the second side hole, and can flow relatively smoothly within the tube 101. When all the side holes 106 are blocked by thrombi, suction continues. Under the action of suction pressure, the thrombi at each side hole 106 are drawn into the tube body 101 at almost the same time, so that each side hole 106 can be reopened. If suction continues, the above suction process is repeated.

[0057] Therefore, by setting the multiple side holes 106 in the circumferential direction of the tube body 101 to have different diameters (gradient distribution), this application can basically avoid the problem of fluid flow disorder in the tube body 106, thereby helping to improve the stability of fluid flow in the tube body 101.

[0058] In some embodiments, such as Figure 2 As shown, the diameter of each side hole 106 is d, and the vertical distance from the center of each side hole 106 to the second central axis C2 is L. d and L satisfy the following formula:

[0059]

[0060] Where c is a constant.

[0061] In some embodiments, such as Figure 2 As shown, the center of the side hole 106 with the largest diameter in each row of holes 105 is the first center P1. A radial line C3 of the tube body 101 passing through the first center P1 and the first central axis C1 intersects the second central axis C2. In other words, in the radial direction of the tube body 101, the side hole 106 with the largest diameter and the guide wire cavity 104 are located on opposite sides of the first central axis C1.

[0062] Furthermore, such as Figure 2 As shown, in each row of holes 105, the side holes 106, except for the side hole 106 with the largest diameter, are arranged symmetrically with respect to the radial line C3.

[0063] In some embodiments, such as Figure 2As shown, the inner cavity 102 is divided into a suction cavity 103 and a guide wire cavity 104 by a partition tube 108 disposed in the tube body 101. The partition tube 108 serves as the side wall of the guide wire cavity 104, defining the shape and size of the guide wire cavity 104. The partition tube 108 is connected to the tube body 101 to be fixed inside the tube body 101.

[0064] Optionally, such as Figure 2 As shown, the separator tube 108 is directly connected to the inner wall of the tube body 101, thus eliminating the need for additional connecting ribs or other connectors to connect the separator tube 108 and the tube body 101. This avoids additional space occupied by connectors in the inner cavity 102 of the tube body 101, allowing the inner cavity 102 to be allocated as much as possible to the suction chamber 103, thereby increasing the area of ​​the suction chamber 103.

[0065] Optionally, such as Figure 2 As shown, the separator 108 and the tube body 101 are an integral structure to further reduce the space occupied by the separator 108, increase the area of ​​the aspiration chamber 103, and facilitate the processing and forming of the thrombus aspiration catheter 100.

[0066] Optionally, the diameter of the guidewire cavity 104 is configured to be the minimum diameter suitable for guidewire operation. For example, when the guidewire is a size 14 guidewire, the diameter of the guidewire cavity 104 can be 0.55 mm.

[0067] In some embodiments, such as Figure 1 As shown, the tube body 101 has a proximal end and a distal end. The distal end of the tube body 101 is used to extend into the blood vessel. The distal end of the tube body 101 is provided with an end hole 107 that communicates with the aspiration chamber 103. The end hole 107 and the side hole 106 on the side wall of the tube body 101 work together to aspirate the thrombus.

[0068] Optionally, the distal end face of the tube body 101 is inclined to facilitate movement within the blood vessel.

[0069] In some embodiments, the tube body 101 may be made of polyurethane material with a hardness of 72D, thereby ensuring that the suction catheter does not deform under suction pressure.

[0070] In some embodiments, the diameters of the axially corresponding side holes 106 in the multi-row hole group 105 are equal.

[0071] However, this application is not limited to this. In other embodiments, the diameters of the axially corresponding side holes 106 in the multi-row hole group 105 may also be different.

[0072] Optionally, the number of side holes 106 in each row of hole groups 105 can be 3 to 7. For example, the number of side holes 106 in each row of hole groups 105 is 5.

[0073] In some embodiments, the multi-row hole group 105 is arranged on the tube body 101 within a preset length range, which starts from the distal end of the tube body 101. For example, the preset length range is 2cm to 20cm, preferably 5cm to 20cm, which can achieve effective aspiration of venous thrombi with a common length of 5cm to 20cm.

[0074] In some embodiments, the number of rows of the multi-row hole group 105 can be 3 to 20.

[0075] In some embodiments, the axial spacing between two adjacent rows of holes 105 can be 2 to 30 times the diameter of the largest side hole 106.

[0076] An embodiment of the second aspect of this application provides a thrombus aspiration catheter assembly.

[0077] Figure 3 This is a schematic diagram of a thrombus aspiration catheter assembly according to an embodiment of this application. Figure 3 As shown, the thrombus aspiration catheter assembly of this application embodiment includes a thrombus aspiration catheter 100 and a connecting tube 200. Since the structure of the thrombus aspiration catheter 100 has been described in detail in the first aspect embodiment, the content is incorporated herein by reference, and the description is omitted here.

[0078] See Figure 3 The connecting tube 200 is used to connect the tube body 101 of the thrombus aspiration catheter 100 to the negative pressure aspiration device. The inner diameter D1 of the connecting tube 200 is larger than the inner diameter D2 of the inner lumen 102. Therefore, compared with the thrombus aspiration catheter 100, the pressure drop in the connecting tube 200 is very small, thereby ensuring that there is sufficient aspiration pressure in the aspiration chamber 103 of the thrombus aspiration catheter 100 and improving the aspiration effect.

[0079] Optionally, the inner diameter D1 of the connecting pipe 200 is not less than twice the inner diameter D2 of the inner cavity 102. For example, when the inner diameter D2 of the inner cavity 102 is 3 mm, the inner diameter D1 of the connecting pipe 200 is greater than or equal to 6 mm.

[0080] When using the thrombus aspiration catheter assembly of this application for thrombectomy, one end of the connecting tube 200 is connected to the negative pressure aspiration device, and the other end of the connecting tube 200 is connected to the proximal end of the tube body 101. The guidewire is passed sequentially through the guidewire lumen 104 of the connecting tube 200 and the tube body 101. Then, the tube body 101 is inserted into the thrombus site in the blood vessel along the guidewire. The negative pressure device is then activated for aspiration. During the aspiration process, the aspiration operation can be adjusted by rotating and moving the catheter. The entire aspiration process can be recorded by a camera to facilitate the analysis of the thrombus aspiration performance of the aspiration catheter in this application embodiment.

[0081] The present application has been described above with reference to specific embodiments. However, those skilled in the art should understand that these descriptions are exemplary and not intended to limit the scope of protection of the present application. Those skilled in the art can make various modifications and variations to the present application based on its spirit and principles, and these modifications and variations are also within the scope of the present application.

Claims

1. A thrombus aspiration catheter, characterized in that, include: The tube body has an inner cavity with a first central axis. The inner cavity is divided into a suction cavity and a guide wire cavity that are not connected to each other in a direction perpendicular to the first central axis. The guide wire cavity has a second central axis that is offset from the first central axis. The tube body has multiple rows of holes arranged at intervals along the axial direction of the tube body on its side wall. Each row of holes includes multiple side holes arranged at intervals along the circumference of the tube body. Each side hole is connected to the suction chamber. The diameter of the multiple side holes increases with the increase of the vertical distance between the center of the multiple side holes and the second central axis in the direction perpendicular to the second central axis. The diameter of each of the side holes is d The vertical distance between the center of each side hole and the second central axis is... L , d and L Satisfy the following formula: in, c It is a constant.

2. The thrombus aspiration catheter according to claim 1, characterized in that, The center of the side hole with the largest diameter in each row of holes is the first center, and a radial line passing through the first center and the axis of the first center intersects the axis of the second center.

3. The thrombus aspiration catheter according to claim 2, characterized in that, In each row of holes, the side holes, except for the side hole with the largest diameter, are arranged symmetrically with respect to the radial line.

4. The thrombus aspiration catheter according to claim 1, characterized in that, The inner cavity is divided into the suction cavity and the guide wire cavity by a partition tube disposed within the tube body, and the partition tube is connected to the tube body.

5. The thrombus aspiration catheter according to claim 4, characterized in that, The separator tube is directly connected to the inner wall of the tube body.

6. The thrombus aspiration catheter according to claim 5, characterized in that, The separator tube and the tube body are an integral structure.

7. The thrombus aspiration catheter according to claim 1, characterized in that, The tube has a distal end, and the distal end has an end hole that communicates with the suction chamber.

8. A thrombus aspiration catheter assembly, characterized in that, include: The thrombus aspiration catheter according to any one of claims 1 to 7; A connecting tube is used to connect the body of the thrombus aspiration catheter to the negative pressure aspiration device, wherein the inner diameter of the connecting tube is larger than the inner diameter of the lumen.

9. The thrombus aspiration catheter assembly according to claim 8, characterized in that, The inner diameter of the connecting pipe is not less than twice the inner diameter of the inner cavity.

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