A thrombectomy balloon catheter

Abstract

The present application relates to a thrombectomy balloon catheter, which comprises a balloon, a catheter body, a connecting piece and a catheter hub. The balloon is nested outside the catheter body to form a balloon cavity, a guide wire cavity is formed inside the catheter body, a guide wire inlet of the guide wire cavity is formed in the middle of the catheter body, and a guide wire outlet of the guide wire cavity is formed at the distal end of the catheter body. The connecting piece is connected to the balloon cavity so that fluid can be injected through the connecting piece to expand the balloon. Wherein, a convex portion protruding outward is formed on the outer periphery of the balloon along the circumferential direction of the thrombectomy balloon catheter. When the balloon is in an expanded state, the convex portion unfolds to scrape the thrombus in the blood vessel, so that the thrombus falls off. The thrombectomy balloon catheter of the present application can perform thrombectomy simply and conveniently.

Description

Technical Field

[0001] The present application relates to a medical device, and more particularly, to a thrombectomy balloon catheter. Background Art

[0002] Acute ischemic stroke is a neurological tissue injury caused by local cerebral tissue ischemia necrosis due to sudden obstruction of cerebral blood flow. 70% - 80% of patients with severe symptoms requiring arteriography can be seen with emboli or thrombus obstruction. The fatality rate of large vessel embolism is between 53% - 92%. Recanalization of blood vessels is the key to the treatment of acute ischemic stroke. Currently, the conventional methods for treating acute ischemic stroke include two major categories: interventional thrombolysis and mechanical thrombectomy.

[0003] Interventional thrombolysis is that a catheter injects a thrombolytic agent into the lesion near the blood vessel where the lesion is located, forming a very high concentration of thrombolytic agent locally at the lesion, thereby accelerating the thrombolysis rate and increasing the chance of blood vessel recanalization. However, intravenous or arterial thrombolytic therapy has very poor effects on the thrombus in the proximal segment of the distal end of the internal carotid artery and the M1 segment of the middle cerebral artery, which is largely related to the too large absolute volume of the blood clot. Therefore, a very large dose of thrombolytic drug is required to dissolve such a large blood clot, but this is likely to cause complications and has a high risk.

[0004] Mechanical thrombectomy includes thrombectomy, laser thrombolysis, capture thrombectomy and capture net thrombectomy. Thrombectomy is relatively thorough, but causes too much damage to the blood vessel wall and is extremely likely to cause various complications. Laser thrombolysis has a high operation difficulty. Low laser energy is ineffective, and too high energy will damage the blood vessel, and it is also likely to cause various complications. Capture thrombectomy is simple to operate and causes little damage to the blood vessel wall, but often cannot catch the blood clot. Capture net thrombectomy is simple to operate, but cannot be used in intracranial blood vessels due to the large volume of the capture net. Summary of the Invention

[0005] Therefore, an improved intracranial thrombectomy device is needed. This device should be able to perform thrombectomy simply and conveniently, have a high capture rate, and when retrieving the thrombus after capture, make the thrombus firmly fixed and not easily fall off.

[0006] Furthermore, the improved intracranial thrombectomy device preferably also has the following characteristics: small volume, good wall attachment and flexibility. Thanks to such characteristics, the intracranial thrombectomy device can be conveniently transported to the distal blood vessels in the brain, and will not damage the inner wall of the blood vessel during the thrombectomy process.

[0007] In order to solve the above problems, the purpose of the present application is to provide a novel thrombectomy balloon catheter, which can effectively correct the limitations of the existing treatment measures for thromboembolic diseases and benefit patients.

[0008] To achieve the above object, the present application provides a thrombectomy balloon catheter, which includes a balloon, a catheter body, a connector, and a catheter hub. The balloon is nested outside the catheter body to form a balloon cavity, a guide wire cavity is formed inside the catheter body, a guide wire inlet of the guide wire cavity is formed in the middle of the catheter body, and a guide wire outlet of the guide wire cavity is formed at the distal end of the catheter body. The connector is connected to the balloon cavity, so that fluid can be injected through the connector to expand the balloon; wherein, a convex portion protruding outward is formed on the outer periphery of the balloon along the circumferential direction of the thrombectomy balloon catheter. When the balloon is in the expanded state, the convex portion unfolds to scrape the thrombus in the blood vessel, so that the thrombus falls off.

[0009] In a preferred embodiment of the present application, the thrombectomy balloon catheter further includes a catheter sheath, and a corresponding concave portion recessed inward is formed on the outer periphery of the balloon along the circumferential direction of the thrombectomy balloon catheter at the proximal end of the convex portion. The concave portion receives the fallen thrombus, and the thrombus moves into the catheter sheath along with the thrombectomy balloon catheter.

[0010] In a preferred embodiment of the present application, the angle formed by the proximal surface of the convex portion facing the corresponding concave portion and the axial direction is between 10 and 90 degrees, and the height of the convex portion is between 0.5 mm and 10 mm.

[0011] In a preferred embodiment of the present application, a plurality of convex portions and concave portions are alternately formed along the axial direction of the thrombectomy balloon catheter.

[0012] In a preferred embodiment of the present application, the number of the convex portions is between 2 and 15.

[0013] In a preferred embodiment of the present application, when the balloon is not in the expanded state, the convex portion adheres to the catheter body.

[0014] In a preferred embodiment of the present application, the convex portion adheres to the catheter body through a folding structure.

[0015] In a preferred embodiment of the present application, the length of the balloon catheter is between 1000 mm and 2500 mm.

[0016] In a preferred embodiment of the present application, contrast agent is injected through the connector to expand the balloon.

[0017] In a preferred embodiment of the present application, the balloon is a semi-compliant balloon.

[0018] The methods and apparatuses of the present application may have other characteristics and advantages, which will be apparent from the accompanying drawings incorporated herein and the subsequent detailed description, or will be described in detail in the accompanying drawings incorporated herein and the subsequent detailed description. These drawings and the detailed description are used together to explain the specific principles of the present application. Description of the Drawings

[0019] Figure 1 A general schematic diagram of a thrombectomy balloon catheter according to the present application is shown.

[0020] Figure 2 A partial cross-sectional view along the longitudinal axis of the thrombectomy balloon structure according to the present application is shown, wherein the thrombectomy balloon is in an expanded state.

[0021] Figure 3 A partial cross-sectional view perpendicular to the longitudinal axis of the thrombectomy balloon structure according to the present application is shown, wherein the thrombectomy balloon is in a contracted state.

[0022] Figure 4 A partial perspective view of the thrombectomy balloon structure according to the present application is shown, wherein the thrombectomy balloon is in a contracted state.

[0023] It should be understood that the accompanying drawings are not necessarily drawn to scale, but are merely schematic representations of the various features of the basic principles of the present application in a suitably simplified manner. The specific design features of the present application included herein (including, for example, specific dimensions, directions, positions, and shapes) will be determined in part by the environment in which the present application is to be applied and used.

[0024] In the drawings, the same reference numerals refer to the same or equivalent parts of the present application. Detailed Description

[0025] Reference will now be made in detail to the various embodiments of the present application, examples of which are shown in the drawings and described below. Although the present application will be described in conjunction with the exemplary embodiments, it should be understood that the present specification is not intended to limit the present application to those exemplary embodiments. On the contrary, the present application is intended to cover not only these exemplary embodiments but also all alternative forms, modifications, equivalent forms, and other embodiments that may be included within the spirit and scope of the present application as defined by the appended claims.

[0026] The terms used herein merely describe particular embodiments and do not limit the present application. Additionally, unless the context clearly indicates otherwise, a singular recitation shall be construed to include a plural recitation. It is understood that the terms "comprising," "including," or "having" are intended to specify the presence of the features, steps, operations, elements, and components described in the specification, or combinations thereof, but do not preclude the presence of one or more other features, steps, operations, elements, and components, combinations thereof, or other possibilities.

[0027] Terms including ordinal numbers (such as "first" or "second", etc.) may be used to describe various components, but these components are not limited by the order of these terms. The terms are used solely for the purpose of distinguishing one component from another. For example, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component without departing from the scope of the rights of the present application. The term "and / or" includes any combination of multiple items or any one of multiple items.

[0028] Hereinafter, various exemplary embodiments of the present application will be described in more detail with reference to the accompanying drawings.

[0029] First, in order to more clearly describe the embodiments of the present application, the "proximal end" and "distal end" are defined according to common terms in the medical field.

[0030] When a physician holds a tool or instrument to perform normal operations facing a patient and the tool or instrument is located between the physician and the patient, the end closer to the physician is called the "proximal end" or "proximal", and the end farther from the physician (this end is closer to the patient) is called the "distal end" or "distal".

[0031] The above definitions of the "proximal end" and "distal end" are only for convenience in describing the embodiments of the present application and do not limit the structure of the present application. Optionally, the "proximal end" may also be referred to as the first end, and the "distal end" may correspondingly be referred to as the second end.

[0032] Now reference will be made to Figures 1 to 4 to describe the structure of the thrombectomy balloon catheter 1 of the exemplary embodiment of the present application.

[0033] Reference Figure 1 and Figure 2 , according to the exemplary embodiment of the present application, the thrombectomy balloon catheter 1 includes a balloon 10, a catheter body 20, a connector, a catheter sheath, and a catheter hub, and adopts a rapid exchange structure to facilitate the clinical operation of the physician..

[0034] The balloon 10 is nested outside the tube body 20 and fixed together. The distal end of the balloon 10 is fixed to the outer wall of the tube body 20, forming an airtight structure at the connection position 19, so that the balloon 10 forms a closed space. The balloon 10 and the tube body 20 are of a double-lumen structure. The guide wire lumen 21 in the tube body 20 is used for the entry and exit of the guide wire, and the balloon lumen 11 is used for the expansion of the balloon 10. Sufficient remaining space is reserved in the balloon 10 to allow the passage of fluid. Fluids such as contrast agents can be injected through the connecting piece to expand the balloon 10. After the balloon 10 is connected to the tube body 20, the inside should allow the passage of the guide wire lumen 21. The guide wire lumen 21 penetrates through the middle of the tube body 20 to form a guide wire inlet while retaining the lumen between the tube body 20 and the catheter hub. A guide wire outlet 22 of the guide wire lumen is formed at the distal end of the distal section of the tube body.

[0035] The connection and fixation methods between the various parts are, for example, laser welding, hot air fusion welding, physical adhesion, etc., among which welding is preferred, and laser welding is more preferred.

[0036] Preferably, the balloon 10 is a semi-compliant balloon, which reduces the damage to the blood vessel wall compared to a compliant balloon when the balloon expands. Those skilled in the art should understand that a compliant balloon means that after the pressure increases to the nominal pressure or expands to a predetermined size, as the inflation pressure increases, the size of the balloon can still continuously increase. In contrast, a semi-compliant balloon means that after the pressure increases to the nominal pressure or expands to a predetermined size, as the inflation pressure increases, the size of the balloon can increase within a small range.

[0037] By adopting specific materials, structures, and specific processes (such as electrothermal forming processes, etc.), the wall thicknesses of the balloon 10 and the tube body 20 in the exemplary embodiments of the present application are thinner and the walls are softer compared to the prior art. For example, the balloon 10 is made of a softer material, and the material is selected from block polyetheramide elastomers (commercially available under the name PEBAX), nylon, polyurethane (PU), polyester, polyamide compounds, etc., or a mixture thereof. The single wall thickness of the balloon 10 is about 10 to 15 microns, such as 10 microns, 11 microns, 12 microns, 13 microns, 14 microns, 15 microns. In contrast, the wall thickness of the balloon in the prior art is 20 to 25 microns. For balloons of the same specification, the bending degree of the balloon 10 in the exemplary embodiments of the present application reaches about 45 degrees in the erected state, which is much larger than that of the balloons in the prior art. The smaller outer passing diameter and better flexibility greatly improve the passing performance of the balloon catheter into the lesion, and cause very little damage to the blood vessel wall during the thrombectomy process.

[0038] Preferably, the length of the balloon catheter is between 1000 mm and 2500 mm, preferably 1500 mm or 2000 mm. Such a length is beneficial for reaching more distant lesions and covers the needs of more patients.

[0039] Further reference Figure 2, the thrombectomy balloon according to the exemplary embodiments of the present application includes convex portions 12 and concave portions 13 that alternate in the axial direction of the thrombectomy balloon catheter 1. The convex portions 12 are formed on the outer periphery thereof along the circumferential direction of the thrombectomy balloon catheter 1 and bulge outward. When the balloon 10 is in the expanded state, the convex portions 12 exhibit an unfolded umbrella shape or rake shape. The sizes of the balloon 10 and the convex portions 12 are set such that when the balloon 10 is in the expanded state, the convex portions 12 contact the blood vessel wall and can scrape the thrombus in the blood vessel to make the thrombus fall off.

[0040] The concave portions 13 are formed on the outer periphery thereof along the circumferential direction of the thrombectomy balloon catheter 1. Each concave portion 13 is located at the proximal end of the corresponding convex portion 12 and is recessed inward for receiving the fallen thrombus. When the balloon catheter is dragged back into the catheter sheath, the groove portion will carry the received thrombus out of the blood vessel, so that the thrombus enters the catheter sheath along with the balloon catheter, playing a role in thrombectomy.

[0041] Preferably, when the balloon 10 is in the expanded state, the height of the convex portion 12 is between 0.5 mm and 10 mm, preferably 2 mm, 5 mm or 10 mm. The height of the convex portion 12 refers to the difference between the maximum outer diameter at the convex portion 12 and the outer diameter of the concave portion 13. The angle formed by the proximal surface of the convex portion 12 facing the corresponding concave portion 13 and the axial direction is between 10 and 90 degrees, preferably 30 degrees, 60 degrees or 90 degrees. Such sizes and shapes are conducive to making the thrombus fall off and receiving the fallen thrombus, and avoiding the thrombus from moving to other positions via the blood vessel.

[0042] Preferably, a plurality of convex portions 12 and concave portions 13 are formed. In Figure 1 and Figure 4 In the shown exemplary embodiment, the number of convex portions 12 is 7, but the thrombectomy balloon catheter 1 of the present application is not limited thereto. For example, the number of convex portions 12 can be between 2 and 15, preferably 4, 6, 7 or 8.

[0043] The advantage of forming a plurality of convex portions 12 and concave portions 13 is that if there is too much thrombus to be received in a single concave portion 13, or the thrombus detaches from the concave portion 13 during the process of dragging the balloon catheter, then other grooves on the distal side can receive the thrombus again, greatly improving the one-time success rate of thrombectomy.

[0044] Referring to Figure 3 and Figure 4 , the balloon 10 according to the exemplary embodiments of the present application is in the contracted state, and the convex portion 12 adheres to the tube body 20, thereby reducing the outer diameter of the balloon 10 and improving the passability. In a preferred embodiment, the convex portion 12 adheres to the tube body 20 through a folding structure. The folding method is, for example, Figure 3 the five-fold spiral shown, but the present application is not limited thereto.

[0045] Now, a method of using the thrombectomy balloon catheter 1 according to an exemplary embodiment of the present application will be described.

[0046] In interventional therapy, first, the lesion location of the intracranial blood vessel is determined by angiography. Then, a catheter sheath is inserted into the blood vessel through the femoral artery or brachial artery. A guide wire is threaded through the catheter sheath and through the lesion site. The thrombectomy balloon catheter 1 is introduced into the blood vessel and pushed along the guide wire to reach the lesion site. The catheter hub is connected to a pressurizing device, and an appropriate volume of contrast agent is injected into the balloon cavity 11 to expand the balloon 10. The proximal end of the balloon 10 is dragged, and the thrombus in the blood vessel is scraped by the protrusion 12 to cause the thrombus to fall off. The fallen thrombus is received by the recess 13. The balloon 10 and the thrombus are removed from the blood vessel together and transferred into the catheter sheath. The thrombectomy balloon catheter 1 and the catheter sheath are withdrawn from the blood vessel together to complete the thrombectomy operation.

Claims

1. A thrombectomy balloon catheter, characterized in that, It includes a balloon, a shaft, a connector and a catheter hub. The balloon is nested outside the shaft to form a balloon cavity, a guide wire cavity is formed inside the shaft, a guide wire inlet of the guide wire cavity is formed in the middle of the shaft, and a guide wire outlet of the guide wire cavity is formed at the distal end of the shaft. The connector is connected to the balloon cavity so that fluid can be injected through the connector to expand the balloon; Wherein, the balloon includes a convex portion that protrudes outward on the outer periphery of the balloon along the circumferential direction of the thrombectomy balloon catheter. When the balloon is in the expanded state, the convex portion presents an unfolded umbrella shape, and the balloon is dragged to scrape the thrombus in the blood vessel through the convex portion, so that the thrombus falls off and the fallen thrombus is received; The thrombectomy balloon catheter further includes a catheter sheath, and a corresponding concave portion that recesses inward is formed on the outer periphery of the balloon along the circumferential direction of the thrombectomy balloon catheter at the proximal end of the convex portion. The angle formed by the proximal surface of the convex portion facing the corresponding concave portion and the axial direction is between 10 and 90 degrees. The concave portion receives the fallen thrombus, and the thrombus moves into the catheter sheath along with the thrombectomy balloon catheter; The height of the convex portion is between 0.5 mm and 10 mm.

2. The thrombectomy balloon catheter according to claim 1, wherein, A plurality of convex portions and concave portions are alternately formed along the axial direction of the thrombectomy balloon catheter.

3. The thrombectomy balloon catheter according to claim 2, wherein, The number of the convex portions is between 2 and 15.

4. The thrombectomy balloon catheter according to claim 1, wherein, When the balloon is not in the expanded state, the convex portion adheres to the shaft.

5. The thrombectomy balloon catheter according to claim 4, wherein The convex portion adheres to the shaft through a folding structure.

6. The thrombectomy balloon catheter according to claim 1, wherein, The length of the balloon catheter is between 1000 mm and 2500 mm.

7. The thrombectomy balloon catheter according to claim 1, wherein Inject contrast agent through the connector to expand the balloon.

8. The thrombectomy balloon catheter according to claim 1, wherein The balloon is a semi-compliant balloon.

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