A nested plugging device

Abstract

The present invention relates to a nested occluding device, comprising a woven body, wherein the woven body comprises at least two sections of occluding stents; two adjacent sections of the occluding stents are connected by a nested structure, wherein the nested structure comprises a first connecting surface arranged on one of the occluding stents and a second connecting surface arranged on the other occluding stent; the first connecting surface is a connecting protrusion, and a connecting groove corresponding to the connecting protrusion is arranged on the second connecting surface, and the connecting protrusion is connected to the connecting groove by any one of clamping, welding, heat sealing or integral molding; by configuring the woven body into a multi-section occluding stent structure, two adjacent sections of the occluding stent are connected by the nested structure, thereby increasing the flexibility of the occluding device, adapting to a tortuous delivery pathway and an irregular cavity, and improving the radial supporting force of the stent as a whole.

Description

Technical Field

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

[0002] Since thoracic endovascular aortic repair (TEVAR) was applied to the treatment of aortic dissection, its effectiveness and safety have been widely confirmed and recognized. The purpose of this technology is to block the initial rupture of the dissection and the expansion of the true lumen. However, in clinical treatment, most aortic dissections have many problems that need to be solved after TEVAR. Among them, endoleak is a common complication after TEVAR, which refers to the continued flow of blood into the false lumen from various different pathways, including between the stent graft and the aortic wall, intercostal artery reflux, branch artery involvement, stent fabric damage or leakage, and unsealed distal rupture. Endoleak will cause perfusion and pressurization of the false lumen, which is closely related to late aneurysm formation, rupture and death. Therefore, inducing thrombosis in the false lumen is an unavoidable solution.

[0003] The existing methods for inducing thrombosis in the false lumen mainly include using coils, vascular plugs, candy-plug stents, straight tube coated metal stents, etc. However, the coils in the above methods have the problems of small size and large number, and other occluding stents have the problems of poor flexibility and weak radial support force, so a new type of occluding device is urgently needed. Summary of the invention

[0004] In view of this, the present invention provides a nested occluding device, which increases the flexibility of the occluding device by configuring the braided body into a multi-section occluding stent structure, and connecting two adjacent sections of the occluding stent through a nested structure. The device can adapt to tortuous delivery pathways and irregular cavities, and can improve the overall radial supporting force of the stent.

[0005] The technical solution adopted by the present invention is:

[0006] A nested occluding device comprises a woven body, the woven body comprising at least two sections of occluding brackets; two adjacent sections of the occluding brackets are connected by a nested structure, the nested structure comprising a first connecting surface arranged on one of the occluding brackets and a second connecting surface arranged on the other occluding bracket; the first connecting surface is a connecting protrusion, and the second connecting surface is provided with a connecting groove corresponding to the connecting protrusion, and the connecting protrusion and the connecting groove are connected by any one of snap-fitting, welding, heat sealing or integral molding.

[0007] In a further optimization of the technical solution of the present invention, the connecting protrusion is disc-shaped, column-shaped or cone-shaped, and the connecting groove corresponds to the shape of the connecting protrusion.

[0008] According to a further optimization of the technical solution of the present invention, the braided body comprises at least two layers, and each layer is formed by a double-layer or multi-layer braided mesh; the braided body is braided by no less than 72 metal wires or no less than 48 degradable wires.

[0009] According to a further optimization of the technical solution of the present invention, the two end surfaces of the braided body in the axial direction are flat disc-shaped or arc-shaped; and the two ends of the braided body in the axial direction are gathered and fixed by heat sealing, metal hoop kneading, and metal hoop welding.

[0010] According to a further optimization of the technical solution of the present invention, the braided wire material of the braided body comprises a main wire material and a degradable nanowire, and the nanowire is formed by electrostatic spinning after a degradable high molecular polymer is mixed with an antibacterial material.

[0011] Further optimization of the technical solution of the present invention, the high molecular polymer is any one of PPDO, PLCL, PCL, and PLA; the antibacterial material is any one of triclosan, curcumin, chitosan, and tetracycline hydrochloride; and the main filament is also a degradable high molecular polymer.

[0012] According to a further optimization of the technical solution of the present invention, the braided body is an integrated braided structure, and all of the blocking stents and the nested structures are formed by a molding die.

[0013] According to further optimization of the technical solution of the present invention, the length ratio between any two adjacent sections of the occluding stent is between 1:2 and 2:1; the main wire material is a nickel-titanium alloy with a diameter less than 0.1 mm; and a degradable film is provided on the inner side of the outer wall of the braided body.

[0014] Further optimization of the technical solution of the present invention, the molding die comprises an outer shell and a molding body, the molding body is arranged in the outer shell when working, the outer shell comprises a shell, an upper cover body and a lower cover body, the upper cover body and the lower cover body are respectively arranged at two ends of the shell, and the centers of the upper cover body and the lower cover body are both provided with fixing holes; the molding body comprises a first section molding body, a middle section molding body and a last section molding body which are arranged in sequence, and molding sheets are arranged between adjacent molding bodies, and a limiting hole is arranged in the center of the molding sheet.

[0015] Further optimization of the technical solution of the present invention is that the first section forming body is provided with a groove at one end close to the middle section forming body, and the end face of the other end is a flat disk surface or an arc surface; the diameter of the forming piece is smaller than the diameter of the bottom face of the groove; the middle section forming body is provided with a boss matching the groove at one end, and the groove is provided at the other end; the last section forming body is provided with the boss at one end close to the middle section forming body, and the end face of the other end is a flat disk surface or an arc surface.

[0016] Beneficial effects of the present invention:

[0017] By setting the braided body into a multi-section blocking bracket structure, the overall flexibility is ensured to adapt to irregular filling cavities and improve the filling effect; the two connected sections of the blocking brackets are connected by an integrally formed nested structure, which can improve the safety and flexibility of the braided body while maintaining the integrity of the blocking device, and there are no gaps between the sections.

[0018] The braided body is set to a double-layer structure, and each layer is formed by a double-layer or multi-layer braided mesh. The braided mesh uses more than 72 metal wires, which can improve the support and increase the blocking effect of the braided body. In addition, nanowires with antibacterial materials are mixed in the braided metal wires, so that the blocking device of the present invention has the function of drug loading, which can increase the adaptability of the braided body in the patient's body.

[0019] By setting up a special shaping mold, a convenient shaping device can be provided, thereby improving the production efficiency of the plugging device in the technical solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0021] Figure 1 It is a schematic diagram of the structure in which the end surface of the nested plugging device of the present invention is in an arc shape;

[0022] Figure 2 It is a schematic diagram of the structure of the nested plugging device of the present invention with the end surface being in the shape of a flat disk;

[0023] Figure 3 It is a schematic cross-sectional structure diagram of the nested plugging device of the present invention;

[0024] Figure 4 This is a diagram of the use status of the nested occlusion device of the present invention in a blood vessel;

[0025] Figure 5 It is a schematic diagram of the exploded structure of the shaping mold of the nested plugging device of the present invention.

[0026] In the figure: 1. Braided body; 2. Nested structure; 3. Connector; 6. Shaped piece;

[0027] 11. Blocking stent; 12. Outer wall; 13. Inner wall; 14. Main wire material; 15. Nanowire;

[0028] 21. connecting groove; 22. connecting protrusion;

[0029] 41. upper cover body; 42. shell body; 43. lower cover body;

[0030] 51. first section fixed body; 52. middle section fixed body; 53. last section fixed body; 54. groove; 55. boss;

[0031] 61. Limiting hole. DETAILED DESCRIPTION

[0032] The present invention is described below based on embodiments, but the present invention is not limited to these embodiments. In the following detailed description of the present invention, some specific details are described in detail. In order to avoid confusing the essence of the present invention, known methods, processes, procedures, and components are not described in detail.

[0033] In addition, persons of ordinary skill in the art will appreciate that the drawings provided herein are for illustration purposes and are not necessarily drawn to scale.

[0034] Unless the context clearly requires otherwise, throughout the specification and claims, the words "include", "comprising" and similar words should be interpreted in an inclusive sense rather than an exclusive or exhaustive sense; that is, in the sense of "including but not limited to".

[0035] In the description of the present invention, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0036] In the present invention, in a surgical situation, the end away from the operator is "distal", and the side close to the operator is "proximal".

[0037] See also Figure 1-Figure 5The present invention provides a nested occluding device for the diseased cavity in the artery, comprising a braided body 1, wherein the braided body 1 comprises at least two sections of occluding stents 11, preferably three sections. By dividing the braided body 1 into multiple sections of occluding stents 11, the flexibility of the braided body 1 can be increased, thereby increasing the adaptability of the occluding device and facilitating its transportation and action on irregular diseased parts; in particular, the two adjacent sections of the occluding stents 11 are connected by a nested structure 2, so that the braided body 1 can still maintain an expanded state in an irregular tortuous cavity, occupying the cavity space to the maximum extent, and is more suitable for curved diseased cavities than the integrated device in the prior art. Specifically, the nested structure 2 includes a first connection surface provided on one of the blocking brackets 11 and a second connection surface provided on the other blocking bracket 11; the first connection surface is a connection protrusion 22, and the second connection surface is provided with a connection groove 21 corresponding to the connection protrusion 22. When in use, the first connection surface of the nested structure 2 is wrapped around the second connection surface, and the second connection surface is located upstream of the first connection surface (upstream means that the front end is upstream and the rear end is downstream relative to the introduction of the blocking device). Both connection surfaces are parallel in the radial direction of the woven body 1, which can increase the support force of the middle part of the woven body 1. The connection protrusion 22 is connected to the connection groove 21 by any one of the methods of snap-fitting, welding, heat sealing or integral molding. Different preparation processes can be selected according to different connection methods. For example, by using a welding connection method, each section of the blocking bracket 11 can be formed separately, and after forming, it is welded at the middle position of the first connection surface and the second connection surface. Preferably, an integral molding connection method is adopted.

[0038] like Figure 1 As shown, there is a gap between the connecting protrusion 22 and the connecting groove 21, and the connecting protrusion 22 can be selected to be disc-shaped, columnar or conical, and the connecting groove 21 corresponds to the shape of the connecting protrusion 22. The connection between the connecting protrusion 22 and the connecting groove 21 is a surface connection perpendicular to the side wall of the woven body 1, which can ensure its radial support force; preferably, a conical shape is selected to facilitate the bending of the woven body 1.

[0039] like Figure 3As shown, the braided body 1 includes a two-layer structure consisting of an inner wall 13 and an outer wall 12. The traditional braided body is usually a one-layer structure. The two-layer design can increase the flow resistance effect of the braided body 1, and the inner wall 13 or / and the outer wall 12 are preferably formed by a double-layer or multi-layer braided mesh; in addition, the braided wire material of the braided body 1 includes a main wire material 14 and a degradable nanowire 15, and the nanowire 15 is formed by electrostatic spinning after mixing a degradable polymer with an antibacterial material, and the main wire material 14 can be a metal wire material or a degradable wire material. The braided body 1 is braided and formed by not less than 72 metal wires (the metal wire material can be 72 or 144) or not less than 48 degradable wires. Through high-density weaving, a good flow resistance effect can be achieved without using a coating, and the overall support strength of the braided body 1 is further improved through a multi-layer design, so that it is not easy to deform during work. Nanowires 15 are mixed into the braided wire material, and the nanowires 15 are braided with the main wire material 14 in a one-on-one form. The nanowires 15 are electrostatically spun after mixing high molecular polymers and antibacterial materials, so that the nanowires 15 can be dissolved into the lesion site with antibacterial materials at the site of action, so that the braided body 1 has the function of drug loading, and its adaptability in the tissue is increased by mixing antibacterial and anti-inflammatory substances. Specifically, the high molecular polymer is any one of PPDO, PLCL, PCL, and PLA; the antibacterial material is any one of triclosan, curcumin, chitosan, and tetracycline hydrochloride. In addition to the listed substances, degradable electrostatic spinning containing different therapeutic materials can also be woven according to different treatment purposes.

[0040] The two end surfaces of the braided body 1 in the axial direction in the technical solution of the present invention are flat disc-shaped (such as Figure 2 as shown) or arc-shaped (as shown Figure 1 , Figure 3 and Figure 4 As shown), the flat disc-shaped structure can stabilize the position of the braided body 1 in the cavity, and the arc-shaped structure can reduce damage to the inner wall 13 of the cavity, especially for some narrow cavities with calcification; in addition, during the molding process of the braided body 1, the two ends in the axial direction are gathered and fixed by heat sealing, metal hoop kneading, and metal hoop welding.

[0041] The preferred embodiment of the technical solution of the present invention is that the woven body 1 is an integrated woven structure, and all the blocking brackets 11 and the nested structures 2 are formed by a molding mold, that is, each section of the blocking bracket 11 of the woven body 1 is an integrated structure, and the nested structure 2 between two adjacent sections of the blocking bracket 11 is formed by a molding mold, and a connector 3 is provided between the connecting protrusion 22 and the connecting groove 21.

[0042] Preferably, the length ratio between any two adjacent sections of the occluding stent 11 is between 1:2 and 2:1, so that the lengths between the sections are coordinated and the adaptability can be increased; when the main wire 14 is a metal wire, it is a nickel-titanium alloy with a diameter less than 0.1 mm. Since the metal wire is thinner and the gaps between the wires are larger, a degradable film is provided on the inner side of the outer wall 12 of the braided body 1. When the main wire 14 is a degradable wire, it can be a degradable polymer material. In order to ensure the strength of the polymer material, the diameter generally used is larger than that of the metal wire. Therefore, when the degradable main wire 14 is used, a degradable film may be provided on the inner side of the outer wall 12 thereof, or it may not be provided.

[0043] like Figure 5 As shown, the molding die of the braided body 1 includes an outer shell and a molding body, and the molding body is arranged in the outer shell when working, and the outer shell includes a shell body 42, an upper cover body 41 and a lower cover body 43, and the upper cover body 41 and the lower cover body 43 are respectively arranged at the two ends of the shell body 42, and the centers of the upper cover body 41 and the lower cover body 43 are provided with fixing holes, which are used to fix the two ends of the braided body 1 in the axial direction; the molding body includes a first section molding body 51, an intermediate section molding body and a last section molding body 53 which are arranged in sequence, wherein the number of the intermediate section molding bodies can be 1, 2 or more, and a molding sheet 6 is arranged between adjacent molding bodies, and a limiting hole 61 is arranged in the center of the molding sheet 6. The first section forming body 51 is provided with a groove 54 at one end close to the middle section forming body, and the end face of the other end is a flat disk surface or an arc surface. Specifically, the first section forming body 51 and the last section forming body 53 with different end faces can be selected according to the needs of the product; the diameter of the forming piece 6 is smaller than the diameter of the bottom face of the groove 54, and the forming piece 6 can be just embedded in the groove 54 during shaping; one end of the middle section forming body 52 is provided with a boss 55 matching the groove 54, and the other end is also provided with the groove 54. The shape and size of the groove 54 can be consistent with the groove 54 of the first section forming body 51, and can also be adjusted as needed; the last section forming body 53 is provided with the boss 55 at one end close to the middle section forming body 52, and the end face of the other end is a flat disk surface or an arc surface.

[0044] The method of using the shaping mold in the above technical solution is as follows: first, use the braided wire in the above embodiment to form a cylindrical braided body, compress the braided body and pass one end of it through the fixing hole of the upper cover body 41, then put the first section shaping body 51 into the braided body, and then put the first section shaping body 51 through the limiting hole 61 of the shaping sheet 6, and then push the shaping sheet 6 into the groove 54 of the first section shaping body 51, so that the shaping sheet 6 contacts the bottom surface of the groove 54, and according to this method, put the middle section shaping body 52 and the last section shaping body 53 in turn, and between the two adjacent middle section shaping bodies 52, and finally A stop shaping sheet 6 is placed between an intermediate shaping body 52 and an end shaping body 53; after the upper cover 41 and the shaping body are respectively combined with the braided body, the whole is placed in the shell 42, and the upper cover 41 is covered on the shell 42. Finally, the braided body is passed through the fixing hole of the lower cover 43, and the excess braided body at both ends is removed and shaped at high temperature. After shaping, the intermediate shaping body 52 and the shaping sheet 6 are removed from the braided body, and the two wire ends shaped at the fixing holes of the upper cover 41 and the lower cover 43 are gathered and fixed by heat sealing, metal hoop kneading or metal hoop welding. Thus, the braided body 1 structure in the technical solution of the present invention is produced.

[0045] It should be understood that the above-mentioned embodiments are merely illustrative and not restrictive. Without departing from the basic principles of the present invention, various obvious or equivalent modifications or substitutions that can be made by those skilled in the art to the above-mentioned details will all be included in the scope of the claims of the present invention.

Claims

1. A nested plugging device, characterized in that: It comprises a braided body, wherein the braided body comprises at least two sections of occluding stents formed in one piece; Two adjacent sections of the blocking bracket are connected by a nested structure, and there is no gap between the sections. The nested structure includes a first connection surface provided on one of the blocking brackets and a second connection surface provided on the other blocking bracket; The first connection surface is a connection protrusion, and the second connection surface is provided with a connection groove corresponding to the connection protrusion, and a gap is left between the connection protrusion and the connection groove, so as to facilitate the transportation and action of the occluding device on the irregular lesion site; The braided wire material of the braided body comprises a main wire material and a degradable nanowire, and the nanowire is formed by electrostatic spinning after a degradable high molecular polymer is mixed with an antibacterial material.

2. The nested plugging device according to claim 1, characterized in that: The connecting protrusion is disc-shaped, column-shaped or cone-shaped, and the connecting groove corresponds to the shape of the connecting protrusion.

3. The nested plugging device according to claim 1, characterized in that: The braided body comprises at least two layers, and each layer is formed by a double-layer or multi-layer braided mesh; the braided body is braided by no less than 72 metal wires or no less than 48 degradable wires.

4. The nested plugging device according to claim 1, characterized in that: The two end surfaces of the braided body in the axial direction are in the shape of flat disks or arcs; and the two ends of the braided body in the axial direction are gathered and fixed by heat sealing, metal hoop kneading, or metal hoop welding.

5. The nested plugging device according to claim 1, characterized in that: The high molecular polymer is any one of PPDO, PLCL, PCL, and PLA; the antibacterial material is any one of triclosan, curcumin, chitosan, and tetracycline hydrochloride; and the main filament is also the degradable high molecular polymer.

6. The nested plugging device according to claim 1, characterized in that: The braided body is an integrated braided structure, and all of the blocking brackets and the nested structures are formed by a molding die.

7. The nested plugging device according to claim 1, characterized in that: The length ratio between any two adjacent sections of the occluding stent is between 1:2 and 2:1; the main wire material is a nickel-titanium alloy with a diameter less than 0.1 mm; and a degradable film is provided on the inner side of the outer wall of the braided body.

8. The nested plugging device according to claim 6, characterized in that: The shaping mold comprises an outer shell and a shaping body, wherein the shaping body is arranged in the outer shell during operation. The outer shell includes a shell, an upper cover and a lower cover, wherein the upper cover and the lower cover are respectively arranged at two ends of the shell, and the centers of the upper cover and the lower cover are both provided with fixing holes; The shaping body comprises a first shaping body, a middle shaping body and a last shaping body which are arranged in sequence, and a shaping sheet is arranged between adjacent shaping bodies, and a limiting hole is arranged at the center of the shaping sheet.

9. The nested plugging device according to claim 8, characterized in that: A groove is provided at one end of the first section forming body close to the middle section forming body, and the end face of the other end is a flat disk surface or an arc surface; the diameter of the forming piece is smaller than the diameter of the bottom face of the groove; a boss matching the groove is provided at one end of the middle section forming body, and the groove is provided at the other end; the boss is provided at one end of the last section forming body close to the middle section forming body, and the end face of the other end is a flat disk surface or an arc surface.

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