A single-layer composite stent

Abstract

The application discloses a single-layer composite stent, relates to the field of medical devices, and discloses a single-layer composite stent which comprises a supporting main body and a woven wire mesh, wherein the supporting main body is a self-expanding net tube structure, and a plurality of through holes are arranged at intervals in the supporting main body; the woven wire mesh is arranged in the through holes and wound on the supporting main body; the composite stent can treat stenosis lesions in blood vessels through the supporting main body, and effectively prevent the shedding of plaques at the stenosis lesions through the woven wire; the wall thickness of the single-layer stent is adopted to realize the effect of a double-layer stent, the loss of a blood vessel cavity is minimized, the blood flow is fully ensured to be smooth, and the single-layer composite stent has remarkable clinical significance; the single-layer composite stent has good firmness and composite strength, and is not prone to delamination or even breakage and shedding after implantation, so that other complications are effectively avoided; meanwhile, the release resistance of the single-layer composite stent can be effectively reduced, and the single-layer composite stent is convenient for doctors to operate.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of medical devices, in particular to a single-layer composite stent. BACKGROUND

[0002] Atherosclerosis and other reasons will cause stenosis in blood vessels, thereby affecting the normal flow and supply of blood, and further causing myocardial infarction, stroke, etc., and in severe cases, can cause death. Among them, the common site of vascular stenosis is the carotid artery site. In order to improve the stenosis of the carotid artery, a metal stent is usually placed, and the stent is usually implanted in the blood vessel in a compressed state, and after reaching the stenosis site, the stent is used to open the blood vessel lumen by expanding.

[0003] In the treatment of carotid atherosclerosis by using a stent, the traditional stent structure has a large gap, and the expanded stent can cause the rupture of the plaque, and generate fragments, which can enter the blood flow and flow to the small intracranial blood vessels, thereby causing stroke.

[0004] Although the traditional stent will place an embolic protection device downstream during the operation, the carotid artery position is a branch site, and the plaque detached during the stent expansion process can escape from the gap of the stent to the side branch blood vessels and cause occlusion of the side branch blood vessels.

[0005] At present, in order to prevent the detachment of small plaques, a double-layer stent can be used, which is made by adding a layer of porous composite membrane to the base support element of the bare stent. However, the double-layer stent has a large thickness, which can cause the patient to feel uncomfortable after implantation. The outer layer is covered with a dense porous membrane, which can cause a large friction force with the delivery system during the release of the stent, thereby causing a large release resistance and affecting the operation of the doctor. At the same time, the double-layer stent usually uses a porous high-molecular-fiber layer to composite with the metal stent, which can cause difficulty in ensuring the composite strength, and can cause delamination or even fracture and detachment after implantation, thereby causing other complications. SUMMARY

[0006] The main purpose of the present application is to provide a single-layer composite stent, which aims to solve the technical problems of the current double-layer stent, such as large thickness affecting the patient's feeling, large release resistance, and difficulty in ensuring the composite strength, delamination or even fracture and detachment after implantation.

[0007] To achieve the above-mentioned purpose, the present application provides a single-layer composite stent, which comprises:

[0008] A support body, the support body is a self-expanding net tube structure, and a plurality of through holes are arranged at intervals in the support body;

[0009] A woven wire mesh, the woven wire mesh is arranged in the through hole and wound on the support body.

[0010] In some embodiments, the support body is in a meshed cylindrical structure after expansion, and the woven wire mesh is arranged in the through holes and wound on the support body along the circumferential and / or axial direction of the support body.

[0011] In some embodiments, the support body comprises a plurality of unit rings in a spiral structure, the plurality of unit rings are arranged at intervals along the axial direction of the support body, a plurality of connecting bridges are arranged between adjacent two unit rings, the plurality of connecting bridges are distributed at intervals along the circumferential direction of the unit ring, and two ends of each connecting bridge are connected to two adjacent unit rings respectively.

[0012] The through holes are arranged on the unit ring and the connecting bridge.

[0013] In some embodiments, the unit ring comprises a plurality of V-shaped units connected to each other, the through holes are arranged on both sides of the V-shaped units, and two ends of the connecting bridge are connected to the end portions of the V-shaped units in the adjacent two connecting rings respectively.

[0014] In some embodiments, there are three V-shaped units between adjacent two connecting bridges along the circumferential direction of the unit ring.

[0015] In some embodiments, the woven wire mesh comprises a plurality of ring-shaped wires, the plurality of ring-shaped wires are distributed at intervals along the axial direction of the support body, and the ring-shaped wires are arranged in the through holes and wound on the unit ring and the connecting bridge along the circumferential direction of the unit ring respectively.

[0016] In some embodiments, the woven wire mesh comprises a plurality of ring-shaped wires, the plurality of ring-shaped wires are distributed at intervals along the circumferential direction of the support body, and the ring-shaped wires are arranged in the through holes and wound on the unit ring and the connecting bridge along the axial direction of the unit ring.

[0017] In some embodiments, the ring-shaped wire is in a spiral ring structure.

[0018] In some embodiments, the diameter of the woven wire in the woven wire mesh is 1 / 10-1 / 3 of the thickness of the support body.

[0019] In some embodiments, the mesh pore size of the single-layer composite stent is in the range of 50-100 μm; and / or,

[0020] The outer diameter of the single-layer composite stent after self-expansion is in the range of 3-10 mm.

[0021] The single-layer composite stent provided by the application comprises a support body and a woven wire mesh, wherein the support body is a self-expanding net tube structure, and a plurality of through holes are arranged at intervals in the support body; the woven wire mesh is arranged in the through holes and wound on the support body. The composite stent can treat the stenosis lesion in the blood vessel through the support body, and effectively prevent the plaque at the stenosis lesion from falling off through the woven wire, and the wall thickness of the single-layer stent is used to achieve the effect of the double-layer stent, thereby minimizing the loss of the blood vessel cavity and fully ensuring the smooth flow of blood, which has significant clinical significance. Since the woven wire mesh is arranged in the through holes and wound on the support body, the single-layer composite stent has good firmness and composite strength, and is not prone to delamination or even fracture and falling off after implantation, thereby effectively avoiding other complications; meanwhile, the release resistance of the single-layer composite stent can be effectively reduced, thereby facilitating the operation of doctors. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only constitute some embodiments of the application, and for those skilled in the art, other drawings can also be obtained according to the structures shown in the drawings without creative labor.

[0023] Figure 1 The structure schematic view of an embodiment of the single-layer composite stent provided by the application is shown in the figure.

[0024] Figure 2 The structure schematic view of the support body in the figure is shown in the figure. Figure 1

[0025] Figure 3 The enlarged structure schematic view of the position A in the figure is shown in the figure. Figure 2

[0026] Figure 4 The structure schematic view of the woven wire mesh in the figure is shown in the figure. Figure 1

[0027] The structure schematic view of another embodiment of the single-layer composite stent provided by the application is shown in the figure. Figure 5

[0028] The structure schematic view of the woven wire mesh in the figure is shown in the figure. Figure 6 Figure 5

[0029] Explanation of reference numerals:

[0030] 100-single-layer composite stent; 10-support body; 10a-through hole; 11-unit ring; 12-connection bridge; 20-woven wire mesh; 21-loop wire.

[0031] ​​​​The objectives, functional features and advantages of the present application will be further described with reference to the embodiments in combination with the accompanying drawings. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the protection scope of the present application.

[0033] It should be noted that all the directionality indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative position relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directionality indications also change accordingly.

[0034] In the present application, unless otherwise explicitly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be direct connection, or indirect connection through an intermediate medium; can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For a person of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0035] In addition, the description such as "first", "second", etc. in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the fact that a person of ordinary skill in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the protection scope required by the present application.

[0036] In order to solve the technical problems that the double-layer stent currently used has a large thickness, which affects the patient's feeling, causes a large release resistance, and the composite strength is difficult to guarantee, and after implantation, the risk of delamination or even fracture and shedding occurs, the present application provides a single-layer composite stent 100.

[0037] Please refer to Figures 1 to 6In an embodiment of the present application, the single-layer composite stent 100 comprises a support body 10 and a woven wire mesh 20, wherein the support body 10 is a self-expanding mesh tube structure, and the support body 10 is provided with a plurality of through holes 10a at intervals; the woven wire mesh 20 is arranged in the through holes 10a and wound on the support body 10.

[0038] Specifically, the support body 10 is a mesh stent structure formed by laser engraving and heat treatment or other processes on a super-elastic memory metal pipe, or a mesh stent structure formed by 3D printing on a super-elastic memory metal powder, wherein the super-elastic memory metal can be selected from nickel-titanium alloy, cobalt-chromium alloy or magnesium alloy. The support body 10 has an expanded state and a contracted state. When the single-layer composite stent 100 is delivered, the support body 10 is in the contracted state. When the single-layer composite stent 100 is delivered to the stenosis lesion site in the blood vessel, the single-layer composite stent 100 will release to the radial expansion state, and after radial expansion, it will be in a tubular structure, which can treat the stenosis lesion in the blood vessel. The support body 10 is provided with a plurality of through holes 10a at intervals along its circumferential and axial directions. The shape of the through holes 10a can be circular, square, oval or other reasonable shapes, and the size of the through holes 10a is larger than the radial size of the woven wire. The woven wire used for the woven wire mesh 20 is a nickel-titanium alloy wire, a cobalt-chromium alloy wire or a magnesium alloy wire. A plurality of woven wires are arranged in the plurality of through holes 10a and wound on the support body 10. After winding, a plurality of woven wires form a woven wire mesh 20. During the winding process, the head and the terminal of the woven wire can be fixed on the support body 10 or in the through hole 10a by gluing or welding. The woven wire mesh 20 can reduce the mesh of the support body 10, so that the mesh formed by the single-layer composite stent 100 is relatively dense, which can effectively prevent the shedding of plaques at the stenosis lesion. Since the woven wire mesh 20 is wound in the through holes 10a of the support body 10, the wall thickness of the obtained single-layer composite stent 100 is the wall thickness of the support body 10, and the thickness does not increase, and the same metal material is used, so that the delivery process and release process of the single-layer composite stent 100 are more relaxed. Since the support body 10 is a self-expanding mesh tube structure, the woven wire mesh 20 wound on the support body 10 not only expands radially with the support body 10, but also reduces the mesh area of the support body 10. Thus, the single-layer composite stent 100 of the present application can not only support plaques, but also prevent the shedding of fragments.

[0039] The single-layer composite stent 100 can realize the treatment of the stenosis lesion in the blood vessel through the support body 10, effectively prevent the shedding of the plaque at the stenosis lesion through the braided wire, and realize the effect of the double-layer stent through the wall thickness of the single-layer stent, thereby minimizing the loss of the blood vessel cavity and fully ensuring the smooth blood flow, which has significant clinical significance. Since the braided wire net 20 is arranged in the through hole 10a and wound on the support body 10, the single-layer composite stent 100 has good firmness and composite strength, is not prone to delamination or even fracture and shedding after implantation, and effectively avoids other complications; meanwhile, the single-layer composite stent 100 can effectively reduce the release resistance, thereby facilitating the operation of the doctor.

[0040] In an optional embodiment of the present application, the support body 10 is in a meshed cylindrical structure after expansion, and the braided wire net 20 is arranged in the through hole 10a and wound on the support body 10 along the circumferential direction and / or the axial direction of the support body 10.

[0041] In the embodiment, the support body 10 is in a meshed cylindrical structure after expansion along the radial direction, and the winding mode of the braided wire net 20 can be along the circumferential direction of the support body 10, or along the radial direction of the support body 10, or both along the circumferential direction and the radial direction of the support body 10, or other arbitrary winding modes, as long as the mesh area of the support body 10 can be reduced and the wall thickness is not increased.

[0042] Please refer to Figure 2 and Figure 3 In an embodiment of the present application, the support body 10 comprises a plurality of unit rings 11 in a spiral structure, the plurality of unit rings 11 are arranged at intervals along the axial direction of the support body 10, a plurality of connecting bridges 12 are arranged between the adjacent two unit rings 11, the plurality of connecting bridges 12 are distributed at intervals along the circumferential direction of the unit ring 11, both ends of each connecting bridge 12 are connected to the two unit rings 11 connected thereto, and the through hole 10a is arranged on the unit ring 11 and the connecting bridge 12.

[0043] Specifically, the unit ring 11 is in a spiral ring structure and is in a circular ring structure after radial expansion, a plurality of unit rings 11 are arranged equidistantly along the axial direction of the support body 10, and two adjacent unit rings 11 are connected by a connecting bridge 12, the connecting bridge 12 can be in a linear structure or a bent line structure, a plurality of connecting bridges 12 are arranged equidistantly along the circumferential direction of the unit ring 11, a plurality of through holes 10a are arranged equidistantly along the circumferential direction of each unit ring 11, and the plurality of through holes 10a are arranged on the same cross section, and the connecting bridge 12 is provided with a through hole 10a, and the through hole 10a is arranged at the middle position of the connecting bridge 12, so that the plurality of through holes 10a on the support body 10 are arranged in an array along the circumferential direction and the axial direction, thereby facilitating the winding operation of the woven wire mesh 20.

[0044] Further, in an optional embodiment of the present application, the unit ring 11 comprises a plurality of V-shaped units connected, the through hole 10a is arranged on the two side edges of the V-shaped unit, and the two ends of the connecting bridge 12 are connected to the end portions of the V-shaped units in the adjacent connecting rings.

[0045] Specifically, the through hole 10a is arranged at the middle position of the two side edges of the V-shaped unit, and the two ends of the connecting bridge 12 are connected to the end portions of the V-shaped unit, so that the processing and manufacturing of the support body 10 are facilitated.

[0046] In an optional embodiment of the present application, the length of the two side edges of the V-shaped unit is 2-3mm (such as 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm and interval values between any two end point values), the included angle of the two side edges of the V-shaped unit is 1-3° (such as 1°, 2°, 3° and interval values between any two end point values) when the single-layer composite stent 100 is in a compression state, and the included angle of the two side edges is 20-30° (such as 20°, 22°, 25°, 28°, 30° and interval values between any two end point values) after self-expansion and expansion.

[0047] In a specific embodiment of the present application, there are three V-shaped units between two adjacent connecting bridges 12 in the circumferential direction of the unit ring 11. That is, one connecting bridge 12 is arranged every three V-shaped units.

[0048] Of course, in other embodiments of the present application, there are two, four or five V-shaped units between two adjacent connecting bridges 12, and the specific number is not limited and can be selected according to actual conditions.

[0049] Please refer to Figure 1 and Figure 4In an embodiment of the present application, the woven wire mesh 20 comprises a plurality of looped wires 21, the plurality of looped wires 21 are distributed along the axial direction of the support body 10, and the looped wires 21 are arranged in the through holes 10a along the circumferential direction of the unit rings 11 and are wound on the unit rings 11 and the connecting bridges 12, respectively.

[0050] In the embodiment, the woven wire mesh 20 is wound along the axial direction of the support body 10, specifically, the looped wires 21 are radially expanded into a circular ring structure, and are arranged in the through holes 10a along the axial direction of the support body 10 at equal intervals and are wound on the unit rings 11 and the connecting bridges 12, respectively. Such arrangement can effectively reduce the mesh area of the support body 10, thereby effectively avoiding the detachment of plaques, and also facilitates the winding operation of the looped wires 21.

[0051] The manufacturing steps of the single-layer composite stent 100 provided in the embodiment are as follows: (1) using laser engraving or 3D printing to obtain the support body 10, the specific structure of the support body 10 is referred to the above embodiments, which will not be repeated here; (2) taking a nickel-titanium wire, winding the wire one turn along the through hole 10a of the V-shaped unit of the first unit ring 11 at one end of the support body 10, and fixing the head end and the tail end of the nickel-titanium wire in the through hole 10a by using glue or welding; (3) repeating taking a nickel-titanium wire, winding the wire one turn along the through hole 10a of the first connecting bridge 12, and fixing the head end and the tail end of the nickel-titanium wire in the through hole 10a by using glue or welding; (4) repeating the operations of steps (2) and (3), and sequentially winding the wire on the second unit ring 11, the second connecting bridge 12, the third unit ring 11, the third connecting bridge 12, …, the nth connecting bridge 12, until all the unit rings 11 and the connecting bridges 12 on the support body 10 are wound, thus the manufacturing of the single-layer composite stent 100 is completed.

[0052] Please refer to Figure 5 and Figure 6 In another embodiment of the present application, the woven wire mesh 20 comprises a plurality of looped wires 21, the plurality of looped wires 21 are distributed along the circumferential direction of the support body 10, and the looped wires 21 are arranged in the through holes 10a along the axial direction of the unit rings 11 and are wound on the unit rings 11 and the connecting bridges 12.

[0053] In the embodiment, the woven wire mesh 20 is wound along the axial direction of the support body 10, specifically, each looped wire 21 is arranged in the through hole 10a along the axial direction of the unit ring 11 and is wound on the unit ring 11 and the connecting bridge 12, and the plurality of looped wires 21 are distributed along the axial direction of the support body 10 at equal intervals. Such arrangement can effectively reduce the mesh area of the support body 10, thereby effectively avoiding the detachment of plaques, and also facilitates the winding operation of the looped wires 21.

[0054] It should be noted that the through holes 10a of the V-shaped units on the adjacent two unit rings 11 wound by the same annular wire 21 can be oppositely arranged or staggered, which is not limited herein.

[0055] In an optional embodiment of the present application, the annular wire 21 has a spiral annular structure. That is, the through holes 10a of the V-shaped units on the adjacent two unit rings 11 wound by the same annular wire 21 are staggered, so that the annular wire 21 has a spiral annular structure after being wound and self-expanded.

[0056] The manufacturing steps of the single-layer composite stent 100 provided by the embodiment are as follows: (1) obtaining the support body 10 by laser engraving or 3D printing, and the specific structure of the support body 10 is referred to the above embodiments, which will not be repeated here; (2) taking a nickel-titanium wire, starting to wind the wire from the through hole 10a of one of the V-shaped units on the first unit ring 11 at one end of the support body 10, and then sequentially passing through the through holes 10a of one of the V-shaped units on the second unit ring 11, one of the V-shaped units on the third unit ring 11, …, one of the V-shaped units on the n-th unit ring 11, until reaching the through hole 10a on the last unit ring 11 at the other end of the support body 10, and then returning to wind the wire according to the mirror image route, and finally returning to the through hole 10a on the first unit ring 11, and fixing the head and tail ends of the nickel-titanium wire in the through hole 10a by using glue or welding; (3) repeatedly taking a nickel-titanium wire, and winding the wire by opening one V-shaped unit through hole 10a different from step (2), and winding the wire according to the manner of step (2); until all the unit rings 11 and the connecting bridges 12 on the support body 10 are wound, so that the manufacturing of the single-layer composite stent 100 is completed.

[0057] In an optional embodiment of the present application, the diameter of the braided wire in the braided wire mesh 20 is 1 / 10-1 / 3 (such as 1 / 10, 1 / 9, 1 / 8, 1 / 7, 1 / 6, 1 / 5, 1 / 4, 1 / 3, and interval values between any two endpoint values) of the thickness of the support body 10. In this way, the single-layer composite stent 100 not only has the thickness of the support body 10, but also can reduce the mesh size of the support body 10 through the braided wire mesh 20, so as to cover the plaque and prevent the fragments from falling off.

[0058] In an optional embodiment of the present application, the diameter of the braided wire in the braided wire mesh 20 is 20-50 μm (such as 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, and interval values between any two endpoint values). In this way, the size of the through hole 10a and the wall thickness of the support body 10 do not have to be designed to be large, so as to ensure that the overall weight of the single-layer composite stent 100 is relatively light, and the operation is relatively convenient.

[0059] In an optional embodiment of the present application, the mesh pore size of the single-layer composite stent 100 is in the range of 50-100 μm (for example, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, and interval values between any two endpoint values). Such a design can achieve coverage of plaques and effectively prevent the shedding of fragments.

[0060] In an optional embodiment of the present application, the outer diameter of the single-layer composite stent 100 after self-expansion is in the range of 3-10 mm (for example, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, and interval values between any two endpoint values), so as to adapt to blood vessel cavities of different inner diameters at different parts and be used for treating carotid atherosclerosis.

[0061] The above description is only the preferred embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structural transformation made according to the content of the present application specification and drawings, or direct / indirect application in other related technical fields under the inventive concept of the present application is included in the patent protection scope of the present application.

Claims

1. A single-layer composite stent, characterized in that, The single-layer composite scaffold includes: The support body is a self-expanding mesh-like structure. The support body includes several spiral unit rings. The several unit rings are spaced apart along the axial direction of the support body. Several connecting bridges are provided between two adjacent unit rings. The several connecting bridges are spaced apart along the circumferential direction of the unit rings. Each connecting bridge is connected to two adjacent unit rings at both ends. The unit rings and the connecting bridges are provided with through holes. The several through holes on the support body are arranged in an array along the circumferential and axial directions. A woven wire mesh is inserted into the through hole along the circumferential and / or axial direction of the support body and wrapped around the support body; The single-layer composite support has the same thickness as the support body, and the mesh size of the support body is reduced by the woven wire mesh to cover the patches and prevent debris from falling off.

2. The single-layer composite stent as described in claim 1, characterized in that, The unit ring includes several connected V-shaped units, the through holes are provided on both sides of the V-shaped units, and the two ends of the connecting bridge are respectively connected to the ends of the V-shaped units in two adjacent connected unit rings.

3. The single-layer composite stent as described in claim 2, characterized in that, In the circumferential direction of the unit ring, there are three V-shaped units between two adjacent connecting bridges.

4. The single-layer composite stent as described in claim 1, characterized in that, The woven wire mesh includes a plurality of looped wires, which are spaced apart along the axial direction of the support body. The looped wires pass through the through holes along the circumference of the unit ring and are respectively wound around the unit ring and the connecting bridge.

5. The single-layer composite stent as described in claim 1, characterized in that, The woven wire mesh includes a plurality of looped wires, which are distributed at circumferential intervals along the support body, and the looped wires pass through the through holes along the axial direction of the unit ring and are wound around the unit ring and the connecting bridge.

6. The single-layer composite stent as described in claim 5, characterized in that, The looped filaments have a spiral loop structure.

7. The single-layer composite stent as described in any one of claims 1 to 6, characterized in that, The diameter of the braided wires in the woven mesh is 1 / 10 to 1 / 3 of the thickness of the supporting body.

8. The single-layer composite stent as described in any one of claims 1 to 6, characterized in that, The mesh size of the single-layer composite scaffold ranges from 50 to 100 μm; and / or, The outer diameter of the single-layer composite stent after self-expansion ranges from 3 to 10 mm.

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