Multi-section dense net support assembly

Abstract

The multi-section dense net stent assembly comprises a leading-in sheath, the leading-in sheath is composed of an outer sheath and an inner sheath, an annular channel is formed between the outer sheath and the inner sheath, a main body stent is pressed and held in the annular channel, and an auxiliary body stent is pressed and held in the inner sheath; the outer-layer guide wire is arranged in the guide-in sheath, a pushing block is fixed to the outer-layer guide wire, the pushing block is located in the annular channel and slides, and the pushing block is connected with the inner sheath; and the inner-layer guide wire is arranged in the guide-in sheath, is connected with the auxiliary body stent and is used for pushing the auxiliary body stent to slide in the inner sheath. By arranging the annular channel, the main stent slides, the inner-layer guide wire controls the main stent, the outer-layer guide wire controls the auxiliary stent, adjustment of the relative position between the main stent and the auxiliary stent is achieved, the main stent is released firstly, the auxiliary stent is released after being aligned with an aneurysm opening, the stent is easily aligned with the aneurysm opening, and the operation difficulty is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly relates to a multi-segmented dense mesh stent assembly. Background Art

[0002] Due to its finer mesh and stronger blood flow guiding ability compared to ordinary intracranial stents, the blood flow guiding device is more conducive to the growth of vascular endothelial cells. Through the design of high metal coverage and high mesh porosity, the local blood flow is reshaped, and the impact blood flow from the parent artery into the aneurysm is guided into the distal normal blood vessel, thereby reducing the impact of local blood flow on the aneurysm and improving the hemodynamic situation within the aneurysm. Among blood flow guiding devices, multi-segmented stents are important tools for interventional treatment of complex aneurysms. In existing multi-segmented stents, the design often has a denser mesh in the middle of the stent and a sparser mesh at both ends of the stent. Such a design can not only ensure high metal coverage at the aneurysm orifice to reduce blood flow into the aneurysm; the sparser meshes at both ends of the stent can reduce the impact of the stent on normal blood vessels and improve the flexibility of the stent.

[0003] However, existing multi-segmented stents are mostly integrally designed, and the position of the dense segment in the overall stent cannot be adjusted. This design will cause the self-expanding stent to retract due to elasticity during the release process, resulting in the dense segment sometimes being difficult to completely cover the aneurysm orifice. In addition, if the aneurysm appears in a branch vessel and is relatively close to the bifurcation of the main vessel and the branch vessel, when the dense segment covers the aneurysm orifice, the tail end of the multi-segmented stent is likely to invade the main vessel, interfering with subsequent surgeries in the main vessel. The above situations all pose challenges to the surgical experience of doctors.

[0004] Therefore, a multi-segmented stent with an adjustable position of the dense segment and a release assembly for releasing the stent are needed to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a multi-segmented dense mesh stent assembly. By setting an annular channel for the main stent to slide, the relative position between the main stent and the auxiliary stent is adjusted, and the main stent is released first, and then the auxiliary stent is released after aligning with the aneurysm orifice to solve the above problems.

[0006] To achieve the above purpose, the present invention provides the following technical solution: A multi-segmented dense mesh stent assembly, including an introducer sheath,

[0007] The introducer sheath is composed of an outer sheath and an inner sheath. An annular channel is formed between the outer sheath and the inner sheath. The main stent is crimped inside the annular channel, and the auxiliary stent is crimped inside the inner sheath;

[0008] The outer guide wire is disposed within the introduction sheath. A pushing block is fixedly connected to the distal end of the outer guide wire. The pushing block is located within the annular channel and slides, and the pushing block is connected to the proximal end of the inner sheath.

[0009] The inner guide wire is disposed within the introduction sheath and is used to push the auxiliary body stent to slide within the inner sheath.

[0010] Preferably, the length of the inner sheath is less than that of the outer sheath, and the length of the inner sheath is greater than the length of the auxiliary body stent.

[0011] Preferably, the pushing block is annular and can slide within the annular channel.

[0012] Preferably, the pushing block and the inner sheath are integrally formed.

[0013] Preferably, a developing mark is provided on the pushing block.

[0014] Preferably, the main body stent is a braided large-mesh stent, the auxiliary body stent is a braided dense-mesh stent, and the metal coverage rate of the main body stent is lower than that of the auxiliary body stent.

[0015] Preferably, the metal coverage rate of the main body stent is between 15% and 25%, and the metal coverage rate of the auxiliary body stent is between 25% and 35%.

[0016] Preferably, the distal end of the outer guide wire is provided with multiple bifurcations, and the bifurcations are all connected to the proximal end of the main body stent.

[0017] Preferably, a first developing point is provided on the main body stent.

[0018] Preferably, a second developing point is provided on the auxiliary body stent.

[0019] The technical effects and advantages of the present invention:

[0020] By providing an annular channel for the main body stent to slide, the inner guide wire controls the main body stent, and the outer guide wire controls the auxiliary body stent, so as to realize the adjustment of the relative position between the main body stent and the auxiliary body stent. The main body stent is released first, and the auxiliary body stent is released after aligning with the aneurysm orifice, making it easier for the dense mesh section of the stent to cover the aneurysm orifice and reducing the surgical difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0022] Figure 1 is the overall structure diagram of Embodiment 1 of the present invention;

[0023] Figure 2Exploded view of the outer sheath and inner sheath of the present invention;

[0024] Figure 3 Diagram showing the state of the perforator artery sealed by the mesh stent of the present invention.

[0025] 1. Introduction sheath; 11. Outer sheath; 12. Inner sheath; 21. Outer layer guide wire; 22. Inner layer guide wire; 3. Main body stent; 4. Sub-body stent; 5. Pushing block; 6. Second radiopaque point; 7. First radiopaque point; 8. Radiopaque mark. Detailed implementation mode

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0027] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as up, down, front, back, left, right, etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0028] In the description of the present invention, the meaning of several is one or more, the meaning of multiple is two or more, and understandings such as greater than, less than, exceeding, etc. do not include the present number, and understandings such as above, below, within, etc. include the present number. If there is a description of first and second, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0029] In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more features.

[0030] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the term "connection" should be understood in a broad sense. For example, it may be a fixed connection or a movable connection, or a detachable connection or an inseparable connection, or an integral connection; it may be a mechanical connection, an electrical connection or a connection that can communicate with each other; it may be directly connected, or indirectly connected through an intermediate medium, and may be the internal communication or indirect communication of two elements or the interaction relationship between two elements.

[0031] In the description of the present invention, "distal end" refers to the end farther from the doctor during the operation, and "proximal end" refers to the end closer to the doctor during the operation.

[0032] In the description of the present invention, "before use" refers to the state of the multi-segment thrombectomy stent with variable outer diameter before it is unused, has not entered the human body, or has not come into contact with body fluids such as blood and tissue fluid in the human body. "During use" refers to the state where the multi-segment thrombectomy stent with variable outer diameter has entered the human body or has come into contact with body fluids such as blood and tissue fluid in the human body.

[0033] The present invention provides a multi-segment dense mesh stent assembly. Please refer to Figures 1 - 3 , including an introduction sheath 1, which is composed of an outer sheath 11 and an inner sheath 12. An annular channel is formed between the outer sheath 11 and the inner sheath 12. The main body stent 3 is press-fitted in the annular channel, and the auxiliary body stent 4 is press-fitted inside the inner sheath 12;

[0034] An outer layer guide wire 21 is arranged inside the introduction sheath 1. A pushing block 5 is fixed on the outer layer guide wire 21. The pushing block 5 is located in the annular channel and slides, and the pushing block 5 is connected to the inner sheath 12;

[0035] An inner layer guide wire 22 is arranged inside the introduction sheath 1 and is connected to the auxiliary body stent 4 for pushing the auxiliary body stent 4 to slide inside the inner sheath 12.

[0036] The main body stent 3 and the auxiliary body stent 4 are woven from nitinol wires.

[0037] The outer layer guide wire 21 is used to push the pushing block 5 to move. After the main body stent 3 and the auxiliary body stent 4 move to the position of the aneurysm neck for vascular positioning, the main body stent 3 is longer and unfolds to cover the aneurysm neck opening. The auxiliary body stent 4 can accurately close the aneurysm neck opening and play a good guiding role for blood flow. When in use, first push the outer layer guide wire 21 to drive the pushing block 5 and the inner sheath 12 to move distally. After the main body stent 3 is pushed and released, and after positioning and covering the aneurysm neck position, push the inner layer guide wire 22 distally to release the auxiliary body stent 4 from the inner sheath 12. The unfolded auxiliary body stent 4 can accurately cover the aneurysm opening, thereby reducing the surgical difficulty. By setting the annular channel and the pushing block 5, the relative position between the main body stent 3 and the auxiliary body stent 4 can be adjusted to ensure that the auxiliary body stent 4 can stably cover the aneurysm opening and solve the problem that it is difficult for the dense mesh segment to align with the aneurysm opening that needs to be covered by the stent.

[0038] In the preferred embodiment of the present invention, the length of the inner sheath 12 is less than that of the outer sheath 11, and the length of the inner sheath 12 is greater than that of the auxiliary body stent 4. By making the length of the inner sheath 12 greater than that of the auxiliary body stent 4, the auxiliary body stent 4 can maintain the press-fitted state during the sliding process of the inner sheath 12, avoiding the premature release of the auxiliary body stent 4.

[0039] In a preferred embodiment of the present invention, the pushing block 5 is annular and can slide within the annular channel. The pushing block 5 can provide a stable and uniform thrust to stably release the main body stent 3. In other embodiments of the present application, the pushing block 5 can also be strip-shaped, as long as it can freely slide in the length direction of the annular channel.

[0040] In a preferred embodiment of the present invention, the pushing block 5 and the inner sheath 12 are integrally formed. The pushing block 5 and the inner sheath 12 can be made of the same material, and integral forming reduces the processing difficulty of the pushing block 5 and the inner sheath 12.

[0041] In a preferred embodiment of the present invention, a radiopaque marker 8 is provided on the pushing block 5. The radiopaque marker 8 can be made of a radiopaque material such as nitinol metal or cobalt-chromium metal, and is used to assist the doctor in judging the position of the pushing block 5.

[0042] In a preferred embodiment of the present invention, the main body stent 3 is a braided large-mesh stent, and the auxiliary body stent 4 is a braided dense-mesh stent. The metal coverage rate of the main body stent 3 is lower than that of the auxiliary body stent 4.

[0043] In a preferred embodiment of the present invention, the metal coverage rate of the main body stent 3 is between 15% and 25%, and the metal coverage rate of the auxiliary body stent 4 is between 25% and 35%. If the mesh of the auxiliary body stent 4 is too dense, it will cause perforating branch occlusion, thereby triggering ischemic stroke or neurological deficit. The mesh of the main body stent 3 is larger than that of the auxiliary body stent 4. The main body stent 3 covers the position where the aneurysm occurs, has less impact on blood flow, and at the same time, the length of the main body stent 3 is longer, and the aneurysm in the branch vessel can be covered by the main body stent 3, improving the anchoring effect.

[0044] In a preferred embodiment of the present invention, the distal end of the outer guide wire 21 is provided with multiple bifurcations, and the bifurcations are all connected to the proximal end of the main body stent 3. By providing the outer guide wire 21 with multiple bifurcations, a stable thrust is provided for the pushing block 5. The main body stent 2 is released first, and then the auxiliary body stent 4 is released. The angiography is used to observe the fitting situation between the main body stent 2 and the auxiliary body stent 4 and the interior.

[0045] In a preferred embodiment of the present invention, a first radiopaque point 7 is provided on the main body stent 3. The first radiopaque point 7 is used to indicate the position of the main body stent 3.

[0046] In a preferred embodiment of the present invention, a second radiopaque point 6 is provided on the auxiliary body stent 4. The second radiopaque point 6 is used to indicate the position of the auxiliary body stent 4. Through the first radiopaque point 7 and the second radiopaque point 6, the doctor can be assisted in judging the positional relationship between the main body stent 3 and the auxiliary body stent 4. The first radiopaque point 7 and the second radiopaque point 6 are both fixed by welding.

[0047] Example 1:

[0048] Please refer to Figures 1 - 3, A multi-segmented dense mesh stent assembly, including an introducer sheath 1, which is composed of an outer sheath 11 and an inner sheath 12. An annular channel is formed between the outer sheath 11 and the inner sheath 12. The main body stent 3 is crimped in the annular channel, and the auxiliary body stent 4 is crimped inside the inner sheath 12;

[0049] An outer layer guide wire 21 is arranged inside the introducer sheath 1. A pushing block 5 is integrally formed on the outer layer guide wire 21. The pushing block 5 is located in the annular channel and slides, and the pushing block 5 is connected to the inner sheath 12;

[0050] An inner layer guide wire 22 is arranged inside the introducer sheath 1 and is connected to the auxiliary body stent 4, and is used to push the auxiliary body stent 4 to slide inside the inner sheath 12.

[0051] The main body stent 3 and the auxiliary body stent 4 are woven from nitinol wires.

[0052] The pushing block 5 is annular and can slide in the annular channel. The pushing block 5 can provide stable and uniform thrust to stably release the main body stent 3. A radiopaque marker 8 is welded on the pushing block 5. The radiopaque marker 8 can be made of radiopaque materials such as nitinol metal and cobalt-chromium metal, and is used to assist doctors in judging the position of the pushing block 5.

[0053] The length of the inner sheath 12 is less than that of the outer sheath 11, and the length of the inner sheath 12 is greater than that of the auxiliary body stent 4. During the sliding process of the inner sheath 12, the auxiliary body stent 4 can maintain a crimped state to avoid premature release of the auxiliary body stent 4.

[0054] The metal coverage rate of the main body stent 3 is 15%-25%, and the metal coverage rate of the auxiliary body stent 4 is 25%-35%. Too dense mesh holes of the auxiliary body stent 4 will cause perforating branch occlusion, thereby triggering ischemic stroke or neurological deficit. The mesh holes of the main body stent 3 are larger than those of the auxiliary body stent 4. The main body stent 3 covers the position where the aneurysm occurs, has less impact on blood flow. At the same time, the main body stent 3 is longer, and the aneurysm in the branch vessel can be covered by the main body stent 3, improving the anchoring effect.

[0055] The outer guide wire 21 is used to push the pusher block 5 to move. After the main body stent 3 and the auxiliary body stent 4 move to the position of the aneurysm neck in the blood vessel for positioning, the main body stent 3 is longer and is deployed to cover the aneurysm neck opening. The auxiliary body stent 4 can accurately seal the aneurysm neck opening and play a good guiding role for blood flow. During use, first push the outer guide wire 21 to drive the pusher block 5 and the inner sheath 12 to move distally. After the main body stent 3 is pushed and released, and after positioning and covering the aneurysm neck position, push the inner guide wire 22 distally to release the auxiliary body stent 4 from the inner sheath 12. The deployed auxiliary body stent 4 can accurately cover the aneurysm opening, thereby reducing the surgical difficulty. By setting the annular channel and the pusher block 5, the relative position between the main body stent 3 and the auxiliary body stent 4 can be adjusted to ensure that the auxiliary body stent 4 can stably cover the aneurysm opening and solve the problem that it is difficult to align the aneurysm opening that needs to be covered by the stent in the dense mesh segment.

[0056] The distal end of the outer guide wire 21 is provided with multiple bifurcations, and the bifurcations are all connected to the proximal end of the main body stent 3. By setting the outer guide wire 21 with multiple bifurcations, a stable thrust is provided for the pusher block 5. The main body stent 2 is released first and then the auxiliary body stent 4 is released, and the fitting condition between the main body stent 2 and the auxiliary body stent 4 and the interior is observed by angiography.

[0057] The proximal end of the outer guide wire 21 is arranged in parallel with the inner guide wire 22.

[0058] A first radiopaque marker 7 is provided on the main body stent 3. The first radiopaque marker 7 is used to indicate the position of the main body stent 3. A second radiopaque marker 6 is provided on the auxiliary body stent 4, and the second radiopaque marker 6 is used to indicate the position of the auxiliary body stent 4. Through the first radiopaque marker 7 and the second radiopaque marker 6, the doctor can be assisted in judging the positional relationship between the main body stent 3 and the auxiliary body stent 4.

[0059] In summary: In the present invention, by providing an independent main body stent 3 and an auxiliary body stent 4, first push the outer guide wire 21 to drive the pusher block 5 and the inner sheath 12 to move distally. After the main body stent 3 is pushed and released, then use the outer guide wire 21 to continue to adjust the position of the inner sheath 12. After the inner sheath 12 is positioned and covers the aneurysm neck position, push the inner guide wire 22 distally to release the auxiliary body stent 4 from the inner sheath 12. The deployed auxiliary body stent 4 can accurately cover the aneurysm opening, thereby reducing the surgical difficulty. At the same time, the relative position between the main body stent 3 and the auxiliary body stent 4 can be adjusted to ensure that the auxiliary body stent 4 can stably cover the aneurysm opening and solve the problem that it is difficult to align the aneurysm opening in the dense mesh segment.

[0060] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A multi-section dense mesh support assembly, characterized in that: comprising an introducer sheath (1), The introduction sheath (1) is composed of an outer sheath (11) and an inner sheath (12), wherein an annular channel is formed between the outer sheath (11) and the inner sheath (12), the main body support (3) is pressed and gripped in the annular channel, and the auxiliary body support (4) is pressed and gripped inside the inner sheath (12); An outer guide wire (21) is arranged in the introduction sheath (1), and a push block (5) is fixedly connected to the distal end of the outer guide wire (21), the push block (5) is located in the annular channel and slides, and the push block (5) is connected to the proximal end of the inner sheath (12); The inner guide wire (22) is arranged in the introduction sheath (1) and is used to push the auxiliary body stent (4) to slide in the inner sheath (12).

2. A multi-section dense mesh support assembly according to claim 1, characterized in that: The length of the inner sheath (12) is shorter than that of the outer sheath (11), and the length of the inner sheath (12) is longer than that of the auxiliary body stent (4).

3. A multi-section dense mesh support assembly according to claim 1, characterized in that: The pushing block (5) is annular and can slide in the annular channel.

4. A multi-section dense mesh support assembly according to claim 3, characterized in that: The pushing block (5) and the inner sheath (12) are integrally formed.

5. A multi-section dense mesh support assembly according to claim 4, characterized in that: The pushing block (5) is provided with a developing mark (8).

6. A multi-section dense mesh support assembly according to claim 1, characterized in that: The main body support (3) is a woven large mesh support, the auxiliary body support (4) is a woven dense mesh support, and the metal coverage rate of the main body support (3) is lower than the metal coverage rate of the auxiliary body support (4).

7. A multi-section dense mesh support assembly according to claim 6, characterized in that: The metal coverage rate of the main support (3) is 15%-25%, and the metal coverage rate of the auxiliary support (4) is 25%-35%.

8. A multi-section dense mesh support assembly according to claim 7, characterized in that: The distal end of the outer layer guide wire (21) is provided with a plurality of groups of forks, and the forks are all connected to the proximal end of the main stent (3).

9. A multi-section dense mesh support assembly according to any one of claims 1 to 8, characterized in that: A first developing point (7) is arranged on the main body support (3).

10. A multi-section dense mesh support assembly according to any one of claims 1 to 8, characterized in that: A second developing point (6) is arranged on the auxiliary body support (4).

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