Thrombectomy device and medical device

Abstract

The present invention provides a thrombus removal device and a medical device, wherein the medical device comprises the thrombus removal device, and the thrombus removal device comprises a push shaft, a thrombus removal bracket and a rotation drive mechanism; wherein the proximal end of the thrombus removal bracket is connected to the distal end of the push shaft, and the thrombus removal bracket is configured to be able to rotate around an axis; the distal end of the rotation drive mechanism is connected to the thrombus removal bracket and is used to drive the thrombus removal bracket to rotate. When the thrombus removal device is used to capture a thrombus with a relatively high hardness, a shear force can be generated by the rotation of the thrombus removal bracket, and the interlocking effect between the thrombus removal bracket and the thrombus can be improved under the action of the shear force, thereby improving the thrombus capture effect.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a thrombus removal device and a medical device. Background Art

[0002] Acute stroke is a common cerebrovascular disease with rapid onset, rapid development, severe symptoms, high disability and mortality rates. It is an acute and critical disease among cerebrovascular diseases. Generally speaking, stroke can be divided into two types: hemorrhagic and ischemic, of which ischemic stroke accounts for 70% to 80%. The pathogenesis of acute ischemic stroke is that thrombus or arteriosclerotic plaque detached from the diseased blood vessel wall causes acute occlusion of cerebral arteries, which in turn causes a series of physiological and pathological reactions such as inflammation and apoptosis in ischemic brain tissue. If the blood perfusion of the occluded cerebral artery is restored in a short period of time, the cell metabolism of brain tissue can return to normal and avoid the development of infarction area.

[0003] In the prior art, the main treatments for acute ischemic stroke are intravenous thrombolysis and interventional thrombectomy. Intravenous thrombolysis is the intravenous injection of thrombolytic drugs, and its treatment time window is within three hours after onset. However, most patients miss the treatment time window when they arrive at the hospital after onset, resulting in a serious decline in the thrombolytic effect and failure to effectively open up blocked blood vessels. Interventional thrombectomy is the process of introducing a thrombectomy device through the femoral artery and using the thrombectomy device to remove the embolism. The time window for interventional thrombectomy is within eight hours after onset. In recent years, interventional treatment of acute ischemic stroke has developed rapidly. Based on a series of clinical randomized controlled trials, relevant international organizations have recommended that patients with large vessel occlusion within six hours should give priority to interventional thrombectomy.

[0004] Interventional thrombectomy can be roughly divided into two categories: mechanical thrombectomy and aspiration thrombectomy. Among them, mechanical thrombectomy has gone through the iterations of the first-generation thrombectomy device MERCI, the second-generation thrombectomy device Penumbra (consisting of a reperfusion catheter and a separator) and Solitaire FR (a closed-loop stent engraved by a laser), and the third-generation thrombectomy device Treo (fully visualized) and Revive (distal closed basket). The current mainstream mechanical thrombectomy method is to deliver a microcatheter with an embedded thrombectomy stent into the body with the assistance of a microguidewire, and pass through the thrombus or through the gap between the thrombus and the blood vessel wall to reach the distal side of the thrombus, and then withdraw the microcatheter and release the thrombectomy stent. In this way, the thrombus can be trapped in the thrombectomy stent, and then the thrombectomy stent is withdrawn into the microcatheter, and the thrombus is carried into the microcatheter. Finally, the thrombectomy stent and microcatheter are withdrawn to move the thrombus out of the body. This thrombectomy method mainly utilizes the radial squeezing and interlocking action of the thrombus retriever stent to capture the thrombus. When the radial force of the thrombus retriever stent is insufficient, the thrombus capture effect is poor. Therefore, this method has limitations for large hard thrombi, large-sized cardiac leukocytosis or plaque thrombi that exceed the treatment time window. Summary of the invention

[0005] The purpose of the present invention is to provide a thrombus removal device and a medical device, which have a good capture effect on hard large thrombi, large-sized cardiac thrombi or plaque thrombi.

[0006] To achieve the above-mentioned purpose, the present invention provides a thrombus removal device, comprising a pushing shaft, a thrombus removal bracket and a rotation drive mechanism; wherein the proximal end of the thrombus removal bracket is connected to the distal end of the pushing shaft, and the thrombus removal bracket is configured to be able to rotate around an axis; the distal end of the rotation drive mechanism is connected to the thrombus removal bracket and is used to drive the thrombus removal bracket to rotate.

[0007] Optionally, the pushing shaft comprises a core shaft and a connecting portion, the proximal end of the connecting portion is connected to the distal end of the core shaft, and the distal end of the connecting portion is connected to the proximal end of the thrombus removal bracket;

[0008] The pushing shaft is configured such that at least a portion of the connecting portion can rotate around the axis of the core shaft to allow the thrombus removal bracket to rotate.

[0009] Optionally, the connecting portion is any one of a flexible connecting rope, a flexible double-ring structure or a hinge.

[0010] Optionally, the connecting portion is a ball and socket assembly and includes a base and a sphere, wherein the base is fixedly connected to the distal end of the core shaft and includes a socket, and the sphere is movably disposed in the socket seat and is also fixedly connected to the proximal end of the thrombus removal bracket.

[0011] Optionally, the rotary drive mechanism is sleeved on the outside of the pushing shaft, and the distal end of the rotary drive mechanism is fixedly connected to the proximal end of the thrombus removal bracket;

[0012] The thrombus removal device is configured such that when the rotation drive mechanism rotates around an axis, the rotation drive mechanism drives the thrombus removal bracket to rotate.

[0013] Optionally, the rotation drive mechanism is a cylindrical helical spring structure.

[0014] Optionally, the rotation drive mechanism is a tube.

[0015] Optionally, the rotation driving mechanism is a control rod, the control rod is arranged in parallel with the pushing shaft, and the distal end of the control rod is connected to the proximal end of the thrombus removal bracket;

[0016] The thrombus removal device is configured such that when the control rod revolves around the axis of the pushing shaft, the control rod drives the thrombus removal bracket to rotate.

[0017] Optionally, the thrombus removal stent is a self-expanding structure.

[0018] To achieve the above-mentioned purpose, the present invention also provides a medical device, comprising a microcatheter and a thrombus removal device as described in any of the preceding items, wherein the microcatheter has a second inner cavity that passes axially through the microcatheter; the thrombus removal device is used to be partially disposed in the second inner cavity and is configured to be able to produce axial relative movement with the microcatheter, and the rotational drive mechanism is also configured to be able to produce circumferential relative movement with the microcatheter and drive the thrombus removal bracket to rotate.

[0019] Compared with the prior art, the thrombus removal device and medical device of the present invention have the following advantages:

[0020] The aforementioned thrombus removal device comprises a push shaft, a thrombus removal bracket and a rotation drive mechanism, wherein the proximal end of the thrombus removal bracket is connected to the distal end of the push shaft and is configured to be able to rotate around an axis; the distal end of the rotation drive mechanism is connected to the thrombus removal bracket and is used to drive the thrombus removal bracket to rotate. When the thrombus removal device is delivered to the area where a thrombus exists in the body of the target, and after the thrombus removal bracket is expanded, the thrombus removal bracket is driven to rotate around its axis by the rotation drive mechanism, which can help to improve the interlocking effect between the thrombus removal bracket and the thrombus, thereby facilitating the thrombus removal bracket to capture the thrombus, thereby improving the treatment effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are used to better understand the present invention and do not constitute an improper limitation of the present invention.

[0022] Figure 1 is a schematic structural diagram of a thrombus removal device provided according to an embodiment of the present invention, in which the thrombus removal bracket is in a compressed state;

[0023] Figure 2 is an exploded schematic diagram of a thrombus removal device provided according to an embodiment of the present invention;

[0024] Figure 3 is a schematic structural diagram of a thrombus removal device provided according to an embodiment of the present invention, in which the thrombus removal stent is in an expanded state;

[0025] Figure 4 is a schematic diagram of the structure of a thrombus removal device provided according to an alternative embodiment of the present invention;

[0026] Figure 5a to Figure 5d FIG. 4 is a schematic diagram of a method for using a thrombus removal device according to an embodiment of the present invention.

[0027] [Description of reference numerals is as follows]:

[0028] 100-push shaft, 110-core shaft, 120-connecting part, 121-base, 122-ball, 123-ball socket;

[0029] 200-thrombectomy stent;

[0030] 300-rotation drive mechanism;

[0031] 10- micro guide wire;

[0032] 20-microcatheter;

[0033] 1-Thrombosis. DETAILED DESCRIPTION

[0034] The following is an explanation of the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the present embodiment only illustrate the basic concept of the present invention in a schematic manner, and only the components related to the present invention are shown in the figure instead of being drawn according to the number, shape and size of the components in the actual implementation. The type, quantity and proportion of each component in the actual implementation can be a random change, and the component layout type may also be more complicated.

[0035] In addition, each embodiment of the following description has one or more technical features, but this does not mean that the user of the present invention must implement all the technical features in any embodiment at the same time, or can only implement part or all of the technical features in different embodiments separately. In other words, under the premise that implementation is possible, those skilled in the art can selectively implement part or all of the technical features in any embodiment according to the disclosure of the present invention and according to the design specifications or implementation requirements, or selectively implement a combination of part or all of the technical features in multiple embodiments, thereby increasing the flexibility of the implementation of the present invention.

[0036] As used in this specification, the singular forms "a", "an", and "the" include plural objects, and the plural form "plurality" includes more than two objects, unless the content clearly indicates otherwise. As used in this specification, the term "or" is generally used to include the meaning of "and / or", unless the content clearly indicates otherwise, and the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be directly connected or indirectly connected through an intermediate medium, and it can be a connection between the internal parts of two elements or an interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0037] In order to make the purpose, advantages and features of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings. It should be noted that the drawings are all in very simplified form and in non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. The same or similar reference numerals in the drawings represent the same or similar components.

[0038] In this article, the terms "proximal" and "distal" refer to the relative orientation, relative position, and direction of components or actions relative to each other from the perspective of a doctor using the medical device. Although "proximal" and "distal" are not restrictive, "proximal" usually refers to the end of the medical device that is close to the doctor during normal operation, and "distal" usually refers to the end that first enters the patient's body.

[0039] Figure 1 and Figure 3 FIG. 2 shows a schematic diagram of the structure of a thrombus removal device provided by an embodiment of the present invention. Figure 2 is an exploded schematic diagram of the thrombus removal device.

[0040] Please refer to Figures 1 to 3 The thrombus removal device provided in one embodiment of the present invention comprises a push shaft 100, a thrombus removal bracket 200 and a rotation drive mechanism 300. The proximal end of the thrombus removal bracket 200 is connected to the distal end of the push shaft 100, and the thrombus removal bracket 200 is configured to be able to rotate around its axis. The distal end of the rotation drive mechanism 300 is connected to the thrombus removal bracket 200 and is used to drive the thrombus removal bracket 200 to rotate. When the thrombus removal device is used to capture a thrombus, after the thrombus is trapped in the thrombus removal bracket 200, the user can control the thrombus removal bracket 200 to rotate through the rotation drive mechanism 300 and generate a shear force, so that the bracket edge of the thrombus removal bracket 200 is better embedded in the thrombus, thereby improving the thrombus capture ability of the thrombus removal bracket 200. Even if the radial expansion force of the thrombus removal bracket 200 is insufficient, it can still effectively capture the thrombus to ensure the treatment effect. The maximum rotation angle of the thrombus removal bracket 200 can be 360° or less than 360°, which is not limited in the embodiment of the present invention.

[0041] Please focus on Figure 2 The pushing shaft 100 includes a core shaft 110 and a connecting portion 120, the proximal end of the connecting portion 120 is connected to the distal end of the core shaft 110, the distal end of the connecting portion 120 is connected to the proximal end of the thrombus removal bracket 200, and the pushing shaft 100 is configured so that at least part of the connecting portion 120 can rotate around the axis of the core shaft 110. The purpose of such a configuration is to prevent the pushing shaft 100 from interfering with the rotation of the thrombus removal bracket 200.

[0042] For a specific implementation, please continue to refer to Figure 2The connecting portion 120 is a ball-and-socket assembly, which includes a base 121 and a sphere 122. The proximal end of the base 121 is fixedly connected to the distal end of the mandrel 110, and a ball socket 123 is formed at the distal end of the base 121. The ball 122 can be movably embedded in the ball socket 123, and the ball 122 is also fixedly connected to the proximal end of the thrombus removal bracket 200. Using a ball-and-socket assembly as the connecting portion 120 can avoid kinking, winding, and the like of the connecting portion 120 during the self-rotation of the thrombus removal bracket 120.

[0043] Alternatively, the connection portion may be a flexible connection rope. Alternatively, the connection portion may be a flexible double-loop structure, specifically, the flexible double-loop structure includes a first coil and a second coil, the first coil is fixedly connected to the distal end of the mandrel, the second coil is fixedly connected to the proximal end of the thrombus removal bracket, and the wire of the first coil passes through the inner hole of the second coil, and the wire of the second coil passes through the inner hole of the first coil. Alternatively, the connection portion may be a hinge.

[0044] In the present invention, the structure of the rotation drive mechanism 300 can be selected in many ways, as long as it can be connected to the thrombus removal bracket 200 and can control the rotation of the thrombus removal bracket 200 under the action of external force.

[0045] In an exemplary embodiment, please refer to Figures 1 to 3 , the rotary drive mechanism 300 has a first inner cavity that is axially through, and the first inner cavity is used to pass the pushing shaft 100. In other words, the rotary drive mechanism 300 is sleeved on the outside of the pushing shaft 100, and the distal end of the rotary drive mechanism 300 is fixedly connected to the proximal end of the thrombus removal bracket 200, and preferably the rotary drive mechanism 300 and the thrombus removal bracket 200 are coaxially arranged. The thrombus removal device is configured such that when the rotary drive mechanism 300 rotates, the rotary drive mechanism 300 drives the thrombus removal bracket 200 to rotate. ( Figure 3 The middle arrow indicates the rotation direction of the rotation drive mechanism 300 and the thrombus removal bracket 200 ).

[0046] In a preferred implementation, the rotary drive mechanism 300 is a cylindrical helical spring structure formed by spirally winding a wire around an axis. Its advantages are that it has good bending performance, can pass through tortuous blood vessels, and also has good torsion control, which is easy to control. The wire can be a metal wire, such as a nitinol wire. In other implementations, the rotary drive mechanism can also be a tube.

[0047] In an alternative embodiment, if Figure 4As shown, the rotation drive mechanism 300 is a control rod, which is arranged in parallel with the core shaft 110 of the pushing shaft 100, and the distal end of the control rod is fixedly connected to the proximal end of the thrombus removal bracket 200. When the control rod revolves around the axis of the pushing shaft 100, specifically the core shaft 110, the control rod drives the thrombus removal bracket 200 to rotate.

[0048] It is understood that in the embodiment of the present invention, the thrombus removal stent 200 is a tubular network structure, and is preferably a self-expanding structural member. The so-called "self-expanding structural member" means that the structural member is made of a highly elastic material, which can be deformed when subjected to external pressure (or tension), and can recover the deformation under the action of its own elastic force after the external pressure (or tension) is removed. Self-expanding structural members are usually made of shape memory alloys such as nitinol materials, or made of highly elastic polymer materials. The thrombus removal stent 200 can be a braided stent or a cutting stent. When it is a cutting stent, the present invention does not limit the cutting pattern on the stent wall. Further, the proximal end of the thrombus removal stent 200 is a closed end to facilitate connection with the rotation drive mechanism 200, and the distal end of the thrombus removal stent 200 can be either an open end or a closed end. In addition, a developing element can be provided on the thrombus removal stent 200 to determine the position of the thrombus removal stent 200 when the thrombus removal stent 200 is delivered into the body of the subject.

[0049] Next, combine Figure 5a to Figure 5d The method of using the thrombus removal device is introduced. The connecting portion 120 in the thrombus removal device used here is a ball and socket assembly, and the rotation drive mechanism 300 is a cylindrical helical spring structure.

[0050] Preparation: Take an experimental rabbit and collect 5 ml of blood from its ear vein for later use. Then open the midbrain segment of the intracranial vascular model, mix the rabbit's blood with thrombin and inject it into the midbrain segment of the vascular model, wait for 3 to 5 minutes, confirm that the blood has coagulated (i.e., formed a thrombus), and connect the opened midbrain segment blood vessels back to the intracranial vascular model.

[0051] Usage process:

[0052] First, a micro guide wire 10 is introduced into the blood vessel model, and its distal end reaches the position where the thrombus 1 exists in the artery.

[0053] Next, a microcatheter 20 is introduced into the blood vessel model along the microguide wire 10, and the distal end of the microcatheter 20 reaches the distal end side of the thrombus 1 (such as Figure 5a As shown in FIG. 1 , it can be understood that the micro-catheter 20 has a second inner cavity extending axially therethrough and is sleeved on the outside of the micro-guidewire 10 .

[0054] Next, the micro guide wire 10 is withdrawn.

[0055] Next, the pushing shaft 100 pushes the thrombus removal stent 200 of the thrombus removal device along the second inner cavity of the microcatheter 20 to the distal end of the microcatheter 20. During this process, the thrombus removal stent 200 is in a compressed state (eg, Figure 5b shown).

[0056] Next, the microcatheter 20 is withdrawn and the thrombus removal stent 200 is released. After the thrombus removal stent 200 is released, the thrombus 1 is at least partially sunken into the interior of the thrombus removal stent 200 (eg, Figure 5c shown).

[0057] Next, the user controls the rotation drive mechanism 300 at the proximal end of the thrombus removal device to rotate, so as to drive the thrombus removal bracket 200 to rotate (eg, Figure 5d As shown in the figure, during the self-rotation of the thrombus retrieval stent 200, the thrombus retrieval stent 200 generates shear force, which enhances the interlocking effect between the thrombus retrieval stent 200 and the thrombus 1, and improves the thrombus retrieval stent 200's ability to capture the thrombus 1. It should be noted that in the embodiment of the present invention, there is no restriction on the rotation direction of the thrombus retrieval stent 200, and it can rotate clockwise or counterclockwise.

[0058] After confirming that the thrombus removal stent 200 has effectively captured the thrombus, the user can withdraw the pushing shaft 100 and retract the thrombus removal stent 200 into the microcatheter 20, and finally withdraw the microcatheter 20 and the thrombus removal device as a whole from the body, and the thrombus 1 is removed from the body.

[0059] It should be noted that when the thrombus removal device provided in the embodiment of the present invention is used to capture a thrombus, driving the thrombus removal stent 200 to rotate is not a necessary step. Specifically, when the hardness of the thrombus 1 is relatively small and the radial support force of the thrombus removal stent 200 is sufficient to capture the thrombus 1, the thrombus removal stent 200 may not be rotated. However, when the hardness of the thrombus 1 is relatively large and the radial support force of the thrombus removal stent 200 alone is insufficient to effectively capture the thrombus 1, the rotation of the thrombus removal stent 200 is required to generate shear force to improve the thrombus capture capability.

[0060] Furthermore, an embodiment of the present invention also provides a medical device, comprising the thrombus removal device and the microcatheter 20, wherein the microcatheter 20 has a second inner cavity extending axially therethrough, the thrombus removal device is used to be partially disposed in the second inner cavity, and is configured to be able to generate axial relative movement with the microcatheter 20, and the rotation drive mechanism 300 is also configured to be able to generate circumferential relative movement with the microcatheter 20 and drive the thrombus removal bracket 200 to rotate.

[0061] In the technical solution provided by the present invention, the thrombus removal stent is driven to rotate by a rotary drive mechanism, and while the radial expansion force is used to capture the thrombus, the shear force generated by the rotation of the thrombus removal stent is also used to enhance the interlocking effect between the thrombus removal stent and the thrombus, thereby enhancing its ability to capture the thrombus, making the thrombus removal device particularly suitable for situations where the thrombus is hard and the radial support force of the thrombus removal stent is insufficient. In terms of the method of use, compared with the prior art, the thrombus removal device only adds the step of controlling the rotation of the thrombus removal stent, without increasing the difficulty of operation.

[0062] Although the present invention is disclosed as above, it is not limited thereto. Those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A thrombus removal device, characterized in that: The invention comprises a pushing shaft, a thrombus removal bracket and a rotation driving mechanism; wherein the pushing shaft comprises a core shaft and a connecting portion, the proximal end of the connecting portion is connected to the distal end of the core shaft and is configured to be rotatable around the axis of the core shaft; the proximal end of the thrombus removal bracket is connected to the distal end of the connecting portion to allow the thrombus removal bracket to rotate relative to the pushing shaft around the axis of the thrombus removal bracket; the distal end of the rotation driving mechanism is connected to the thrombus removal bracket; The thrombus removal device is configured such that when the rotation drive mechanism rotates relative to the pushing shaft or revolves around the pushing shaft, the rotation drive mechanism drives the thrombus removal bracket to rotate.

2. The thrombus removal device according to claim 1, characterized in that: The connecting part is any one of a flexible connecting rope, a flexible double-ring structure and a hinge.

3. The thrombus removal device according to claim 1, characterized in that: The connecting part is a ball-and-socket assembly and includes a base and a sphere. The base is fixedly connected to the distal end of the core shaft and includes a socket. The sphere is movably disposed in the socket and is also fixedly connected to the proximal end of the thrombus removal bracket.

4. The thrombus removal device according to claim 1, characterized in that: The rotary drive mechanism is sleeved on the outside of the pushing shaft, and the distal end of the rotary drive mechanism is fixedly connected to the proximal end of the thrombus removal bracket; The thrombus removal device is configured such that when the rotation drive mechanism rotates around an axis, the rotation drive mechanism drives the thrombus removal bracket to rotate.

5. The thrombus removal device according to claim 4, characterized in that: The rotary drive mechanism is a cylindrical helical spring structure.

6. The thrombus removal device according to claim 4, characterized in that: The rotary drive mechanism is a tube.

7. The thrombus removal device according to claim 1, characterized in that: The rotation driving mechanism is a control rod, the control rod is arranged in parallel with the pushing shaft, and the distal end of the control rod is connected to the proximal end of the thrombus removal bracket; The thrombus removal device is configured such that when the control rod revolves around the axis of the pushing shaft, the control rod drives the thrombus removal bracket to rotate.

8. The thrombus removal device according to claim 1, characterized in that: The thrombus removal stent is a self-expanding structure.

9. A medical device, characterized in that: It comprises a microcatheter and a thrombus removal device as described in any one of claims 1 to 8, wherein the microcatheter has a second inner cavity axially extending therethrough; the thrombus removal device is used to be partially disposed in the second inner cavity and is configured to be able to produce axial relative movement with the microcatheter, and the rotary drive mechanism is also configured to be able to produce circumferential relative movement with the microcatheter and drive the thrombus removal bracket to rotate.

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