A blood vessel support structure and artificial blood vessel

Abstract

The present invention belongs to the field of medical device technology, and specifically relates to a vascular support structure and an artificial blood vessel including the vascular support structure. The vascular support structure is a 3D-printed grid structure, each grid includes four grid edges and four grid nodes; the grid nodes are divided into first-class nodes, second-class nodes, third-class nodes, and fourth-class nodes; the vascular support structure is axially divided into a middle bending area and end areas arranged on both sides; the number of nodes in the bending area is 1-3, the grid edges in this area are double-layer edges superimposed up and down, the superimposed cross-section is an oblate shape connected to each other, and the average superimposed wire height in this area is 1.2-1.8 times the wire diameter of the 3D-printed wire; the grid edges in the end area are single-layer edges. The bending area of ​​the vascular support structure of the present invention has good bending performance, can bend to a large extent without bending, and has good support strength, which can better adapt to the natural curvature of blood vessels in the body and the different blood vessel directions.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and in particular relates to a blood vessel support structure and an artificial blood vessel. Background Art

[0002] Cardiovascular disease is the leading cause of death worldwide. The number of people who die from cardiovascular disease each year ranks first among all causes of death, posing a serious threat to human health.

[0003] Vascular support structures play a vital role in the treatment of cardiovascular diseases. Vascular support structures can be implanted as vascular stents to support existing blood vessels, treat narrowing or occlusion of blood vessels due to lesions, and maintain blood flow. In addition, vascular support structures can also serve as a supporting skeleton structure in artificial blood vessels.

[0004] In practical applications, the design of the vascular support structure needs to comprehensively consider factors such as its support force, flexibility, and elasticity. Especially in the implantation locations of blood vessels that require a large degree of bending, such as lower limb blood vessels, or artificial blood vessels that require a large bending angle, such as arteriovenous fistulas, it is necessary to ensure that while providing effective support, the vascular support structure is prevented from bending, thereby improving the clinical effect of the stent and the safety of the patient.

[0005] However, in order to ensure its supporting performance, the existing vascular support structure is usually not flexible enough. Due to its own mechanical strength, it cannot adapt well to the natural bending and movement of blood vessels or artificial blood vessels, especially in some parts that require a large degree of bending. Stress concentration is easily generated at the bend, causing the vascular support structure to bend, thereby narrowing or completely occluding the blood vessel or artificial blood vessel, seriously affecting blood flow, and easily causing damage to the vascular endothelium or rupture and deformation of the artificial blood vessel.

[0006] Therefore, a vascular support structure is urgently needed to solve the above problems. Summary of the invention

[0007] The purpose of this application is to overcome the problem that the vascular support structure in the prior art is not flexible enough and cannot adapt well to the natural bending and movement of blood vessels or artificial blood vessels, thereby providing a vascular support structure with good flexibility and not easy to bend. The vascular support structure has good bending performance, can adapt to different anatomical structures and vascular directions, and is not easy to bend in the curved part.

[0008] In order to achieve the above-mentioned object, the present application provides a vascular support structure, which is a grid-type vascular support structure formed by 3D printing, wherein the grid-type vascular support structure includes a plurality of grids formed by 3D printing threads in the same direction or in a cross-spiral printing, each grid including four grid edges and four grid nodes, and the number of nodes along the cross section of the corresponding node is the number of nodes in the corresponding area of ​​the grid-type skeleton;

[0009] The grid-type vascular support structure is axially divided into three regions, including a bending region located in the middle of the grid-type vascular support structure, and end regions arranged on both sides of the bending region and adjacent to and connected to the bending region; the number of nodes in the bending region is 1-3;

[0010] At least part of the mesh edges of the curved area are double-layer edges printed along the same path so as to overlap each other, and the mesh edges of the end area are single-layer edges;

[0011] The double-layer edge line includes a first layer of wires and a second layer of wires, the cross-section of the first layer of wires and the second layer of wires after superposition is an oblate shape connected to each other, the height after superposition is the superimposed wire height of the first layer of wires and the second layer of wires, and the average superimposed wire height of the bending area is 1.2-1.8 times the wire diameter of the 3D printing wire;

[0012] The nodes include four types of nodes, namely, first-type nodes, second-type nodes, third-type nodes, and fourth-type nodes; the first-type nodes are boundary nodes of the grid-type vascular support structure, which are formed by bending a silk thread; the second-type nodes are connection points of adjacent grids in the end area of ​​the grid-type vascular support structure, which are formed by crossing two silk threads; the third-type nodes are connection points of two adjacent grids in the end area and the curved area of ​​the grid-type vascular support structure, which are formed by two crossed silk threads and a bent silk thread; the fourth-type nodes are connection points of adjacent grids in the curved area of ​​the grid-type vascular support structure, which are formed by crossing four silk threads.

[0013] Preferably, the fourth type of nodes have a staggered structure, and the staggered structure is formed by the connection points formed by the intersection of the second layer of wires deviating from the connection points formed by the intersection of the first layer of wires.

[0014] Further, the dislocation structure at the fourth type of node includes four silk threads that are sequentially printed and connected, wherein the second silk thread is cross-connected to the first silk thread to form a connection point of the first layer of silk threads, the third silk thread is superimposed on the second silk thread at the edge line position, at the fourth type of node position, the third silk thread is bent into a parallel position at the same height as the second silk thread and cross-connected with the first silk thread, the fourth silk thread is superimposed on the first silk thread at the edge line position, at the fourth type of node position, the fourth silk thread is bent away from the first silk thread and cross-connected with the second silk thread and the third silk thread, and the fourth silk thread and the third silk thread form a connection point of the second layer of silk threads;

[0015] The offset distance between the connection points of the first layer of threads and the connection points of the second layer of threads is 0.3-0.5 mm.

[0016] Preferably, at the fourth type of node position, there is a first gap between the third wire and the second wire, and a second gap between the fourth wire and the first wire, thereby forming a tic-tac-toe connection node; the size of the first gap and the second gap is 0.3-0.5mm.

[0017] Preferably, the connection points formed by the crossing of the threads of the second layer are superimposed on the connection points formed by the crossing of the threads of the first layer.

[0018] Preferably, at the third type of node, the second wire is cross-connected to the first wire to form a connection point of the first layer of wires, and the third wire is superimposed on the second wire at the edge position. At the third type of node position, the third wire is bent into an arc or annular connection structure around the connection point of the first layer of wires, and is finally superimposed on the first wire.

[0019] Preferably, the bending region includes a first bending region and a second bending region along the circumferential direction, and an average superimposed wire height of the first bending region is greater than an average superimposed wire height of the second bending region.

[0020] Preferably, a developing structure for displaying the position of the area is provided in the first bending area or the second bending area.

[0021] Preferably, at least part of the grid edge lines of the second curved area have an elastic structure, and the elastic structure is a curved structure.

[0022] Preferably, the average superimposed wire height of the first bending area is 1.2-1.5 times the wire diameter of the 3D printing wire, and the average superimposed wire height of the second bending area is 1.5-1.8 times the wire diameter of the 3D printing wire.

[0023] Preferably, in the double-layer wires, the width of the first layer of wires is greater than the width of the second layer of wires.

[0024] Preferably, the number of nodes in the end region is greater than the number of nodes in the bending region.

[0025] The present invention also relates to an artificial blood vessel, comprising: an artificial blood vessel inner layer, a skeleton layer and an artificial blood vessel outer layer which are arranged in sequence from the inside to the outside.

[0026] Preferably, the inner layer of the artificial blood vessel is an anticoagulant biomaterial, a polymer material with an inert modification, a decellularized extracellular matrix, or a polymer material with an anticoagulant modification; the skeleton layer is a polymer material or a composite material; and the outer layer of the artificial blood vessel is a polyurethane material, silicone, expanded polytetrafluoroethylene, or nylon elastomer material.

[0027] Preferably, the artificial blood vessel inner layer and the artificial blood vessel outer layer are prepared by combining one or more methods including 3D printing, electrospinning, and casting.

[0028] Beneficial effects:

[0029] 1. The number of nodes in the bending area of ​​the vascular support structure of the present invention is 1-3, so that when the vascular support structure is bent, due to the small number of nodes in the bending area and good bending performance, the grid edges of adjacent grids in the bending area are not easy to overlap, thereby avoiding the folding of the bending area caused by the stacking of grid edges, further causing stress concentration in the bending area of ​​the vascular support structure, and causing the risk of bending or even breaking of the vascular support structure. That is, after adopting the above design, the vascular support structure of the present invention can better adapt to the natural bending of blood vessels or artificial blood vessels in the body and different blood vessel directions.

[0030] Furthermore, the grid edge lines in the bending area are set to be double-layer silk threads printed according to the same path and thus superimposed up and down. After the double-layer silk threads are superimposed, mutually connected flat round silk threads are formed. The shape of the silk threads is approximately an I-shaped support structure, and the structure has good supporting performance. Therefore, the design significantly increases the strength and stability of the grid edge lines in the bending area. On the basis that the number of nodes in the bending area is 1-3, which makes the area have higher bending performance, the support strength of the bending area is further increased, so that the bending area is more stable when subjected to pressure or bending, and the risk of rupture or deformation of the artificial blood vessel is reduced.

[0031] 2. Furthermore, the present invention designs a staggered structure at the fourth-type node located in the bending area of ​​the vascular support structure, thereby reducing the height difference between the fourth-type node and the grid edge line of the area, avoiding the risk of fracture of the vascular support structure due to stress concentration caused by the height difference. The reduction in the height difference also makes the mechanical properties of the vascular support structure more uniform, and improves the uniformity of the overall wall of the artificial blood vessel; in addition, it also avoids the risk of damage to the inner wall of the blood vessel due to the height of the fourth-type node being too high, which makes the adaptability of the vascular support structure at the bend of the blood vessel poor.

[0032] 3. In order to ensure the stable connection between the bending area and the end areas on both sides, the present invention designs an arc or annular connection point at the third type of node in the vascular support structure. This design avoids the height difference at the connection between the bending area and the end area, ensures the overall mechanical uniformity of the vascular support structure, and this arc or annular structure also increases the connection strength at the third type of node and reduces the concentrated stress at this location.

[0033] 4. The present invention further divides the bending area of ​​the vascular support structure into two parts, including a first bending area and a second bending area, and designs the average superimposed wire height of the first bending area to be greater than that of the second bending area. The design of different thicknesses enables the vascular support structure to bend in a predetermined direction after implantation, with better flexibility on the outer side of the bend and stronger support performance on the inner side of the bend. This design enables the vascular support structure to bend in a directional manner in the body and has better stability after implantation. Furthermore, the present invention sets a developing structure in the bending area, which is more conducive to the doctor's placement and adjustment of the bending part of the vascular support structure, thereby selecting a predetermined bending direction. In addition, the present invention designs at least part of the grid edge line of the second bending area to be an elastic curved structure, thereby ensuring that the second bending area has better flexibility while the elastic edge line can be slightly deformed under blood flow pressure, which helps to maintain a more stable blood flow pattern and reduce the formation of turbulence and eddy currents.

[0034] 5. The present invention also applies the vascular support structure to an artificial blood vessel, providing an artificial blood vessel that is not easy to bend and has strong support. The artificial blood vessel has good bending performance and strong support in the bent part, and can adapt to different anatomical structures and vascular directions, and is not easy to bend in the bent part. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 A schematic diagram of a planar unfolded structure of a vascular support structure.

[0037] Figure 2 Two wire superimposed cross-sections of the mesh edges in the curved region of the vascular support structure.

[0038] Figure 3 Schematic diagram of the first type of nodes, the second type of nodes, the third type of nodes and the fourth type of nodes of the vascular support structure.

[0039] Figure 4 It is a dislocation structure at the fourth type of node of the vascular support structure.

[0040] Figure 5 It is another dislocation structure at the fourth type of node of the vascular support structure.

[0041] Figure 6 It is an arc-shaped or ring-shaped structure at the third type of node of the vascular support structure.

[0042] Figure 7 Another schematic diagram of the planar unfolded structure of the vascular support structure.

[0043] Figure 8 Another schematic diagram of the planar unfolded structure of the vascular support structure.

[0044] Fig. 9 Schematic diagram of the artificial blood vessel structure.

[0045] 1-vascular support structure; 2-artificial blood vessel inner layer; 3-artificial blood vessel outer layer; 4-grid;

[0046] 5-grid edge; 5.1-first layer of silk thread, 5.2-second layer of silk thread;

[0047] a-the first silk thread, b-the second silk thread, c-the third silk thread, d-the fourth silk thread;

[0048] 6-grid node; 6.1-first type node, 6.2-second type node, 6.3-third type node, 6.4-fourth type node; 6.4.1-connection point of first layer of silk thread, 6.4.2-connection point of second layer of silk thread;

[0049] 7-bending region; 7.1-first bending region; 7.2-second bending region; 8.1-first end region; 8.2-second end region; 9-offset structure; 10-arc structure. DETAILED DESCRIPTION

[0050] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0051] Embodiment 1

[0052] A vascular support structure is a grid-type vascular support structure formed by 3D printing. Figure 1 : is a schematic diagram of the planar unfolded structure of the vascular support structure 1. It can be seen that the grid-type vascular support structure is composed of a plurality of grids 4 formed by 3D printing threads in the same direction or in a cross-spiral printing, wherein each grid 4 includes four grid edges 5 and four grid nodes 6; the grid-type vascular support structure includes a plurality of closed loops, and radially adjacent closed loops share a grid node 6, and the number of nodes along the cross section of the corresponding node is the number of nodes in the corresponding area of ​​the grid-type vascular support structure;

[0053] The grid-type vascular support structure 1 can be divided into three regions in the axial direction, including a bending region 7 located in the middle part of the grid-type vascular support structure, and a first end region 8.1 and a second end region 8.2 arranged on both sides of the bending region 7 and adjacent to the bending region 7.

[0054] Further, by Figure 1 It can be seen that in the bending area 7, the number of nodes along the cross section of the grid node 6 is 2, that is, the number of nodes in the bending area is 2; in the first end area 8.1, the number of nodes along the cross section of the grid node 6 is 4, that is, the number of nodes in the first end area 8.1 is 4, and similarly, the number of nodes in the second end area 8.2 is also 4. Among them, radially adjacent closed loops share one grid node 6.

[0055] It is understandable that after adopting the above design, the number of grid nodes 6 in the bending area 7 of the vascular support structure 1 of the present invention is only 2. Therefore, when the vascular support structure of the present invention is applied to some parts that need to be bent, the grid edges 5 of adjacent grids 4 in the bending area 7 are not easy to be stacked, thereby avoiding the folding of the bending area 7 caused by the stacking of grid edges, further causing stress concentration in the bending area of ​​the vascular support structure, thereby causing the vascular support structure to bend or even break. That is, after adopting the above design, the bending area 7 of the vascular support structure of the present invention has better bendability, can bend to a certain extent without bending, so that it can better adapt to the natural curvature of the blood vessels in the body and different blood vessel directions.

[0056] Furthermore, since the number of nodes in the bending region 7 of the vascular support structure 1 is only two, it may cause the problem that the supporting strength of the vascular support structure in the bending region 7 is weak.

[0057] The present invention also designs that the grid edge line 5 in the curved area 7 is a double-layer wire printed along the same path so as to be superimposed on each other. Figure 2 As shown, the mesh edge line 5 in the bending area 7 is composed of a first layer of wires 5.1 and a second layer of wires 5.2 superimposed thereon, and the cross-section of the two layers of wires after superposition is an oblate shape connected to each other, and the shape of the double-layer wires is approximately an I-shaped support structure, and the structure has good support performance. Preferably, the superposition height of the double-layer wires 5.1 and 5.2 in the bending area 7 is 1.2-1.8 times the wire diameter of the 3D printing wire.

[0058] The mesh edge line 5 in the bending area 7 of the present invention is composed of a first layer of silk threads 5.1 and a second layer of silk threads 5.2 superimposed on each other. Such a design significantly increases the strength and stability of the mesh edge line 5. On the basis that the number of nodes in the bending area is 2, which makes the area have higher flexibility, the support strength of the bending area 7 is further increased, making the bending area 7 more stable when subjected to pressure or bending, thereby reducing the risk of rupture or deformation of the blood vessel support structure 1.

[0059] In addition, if Figure 3 As shown, the grid nodes 6 of the present invention include a first type of node 6.1, a second type of node 6.2, a third type of node 6.3, and a fourth type of node 6.4.

[0060] Since the mesh edges 5 in the curved region 7 of the vascular support structure 1 are double-layered, and the mesh edges 5 in the end regions 8.1 and 8.2 are single-layered, the heights of mesh nodes in different regions and mesh connection points in adjacent regions are different.

[0061] Specifically, the grid nodes 6 of the present invention include first-type nodes 6.1, second-type nodes 6.2, third-type nodes 6.3, and fourth-type nodes 6.4. The first type of node 6.1 is a boundary node of the vascular support structure 1, which is formed by bending a silk thread, that is, the height of the first type of node 6.1 is the height of the silk diameter of a silk thread; the second type of node 6.2 is a connection point of adjacent grids in the two end regions 8.1 and / or 8.2 of the vascular support structure 1, which is formed by crossing two silk threads, that is, the height of the second type of node 6.2 is the superimposed silk diameter height of the two silk threads; the third type of node 6.3 is a connection point of two grids adjacent to the two end regions 8.1 and / or 8.2 and the bending region 7 of the vascular support structure 1, which is formed by two crossed silk threads and a bent silk thread, that is, the height of the third type of node 6.3 is the superimposed silk diameter height of three silk threads; the fourth type of node 6.4 is a connection point of adjacent grids in the bending region 7 of the vascular support structure 1, which is formed by crossing four silk threads, that is, the height of the fourth type of node 6.4 is the superimposed silk diameter height of four silk threads.

[0062] Embodiment 2

[0063] Based on the vascular support structure described in Example 1, it can be seen that since the height of the fourth-type node 6.4 is the superimposed wire diameter height of the four wires, there may be a height difference with the grid edge line 5 due to the fourth-type node 6.4 being too high, thereby causing stress concentration and increasing the risk of fracture; and since the height of the fourth-type node 6.4 is too high, it may also reduce the flexibility of the vascular support structure, making the adaptability of the vascular support structure at the vascular bend worse, thereby causing damage to the inner wall of the blood vessel.

[0064] Based on this, we design a dislocation structure 9 at the fourth type of node 6.4. The fourth type of node 6.4 is the connection point of two adjacent grids in the bending area 7, which is formed by the intersection of four silk threads, and the four silk threads include the first silk thread a, the second silk thread b, the third silk thread c, and the fourth silk thread d, which are printed and connected in sequence. The first silk thread a and the second silk thread b form the first layer of silk threads 5.1, and the third silk thread c and the fourth silk thread d form the second layer of silk threads 5.2. Figure 2 FIG. 5 is a superimposed cross-sectional view of the first layer of wires 5.1 and the second layer of wires 5.2 of the mesh edge lines in the bending region 7. FIG.

[0065] Among them, Figure 4 As shown, the first wire a and the second wire b are cross-connected to form the connection point 6.4.1 of the first layer of wires 5.1, the third wire c is superimposed on the second wire b, and at a position 1 mm away from the connection point 6.4.1 of the first layer of wires, the third wire c is bent into a parallel position at the same height as the second wire b; the fourth wire d is superimposed on the first wire a, and at a position 1 mm away from the connection point 6.4.1 of the first layer of wires, the fourth wire d is bent into a parallel position at the same height as the first wire a, and crosses with the third wire c to form the connection point 6.4.2 of the second layer of wires 5.2; wherein the deviation distance between the connection point 6.4.1 of the first layer of wires and the connection point 6.4.2 of the second layer of wires is 0.3-0.5mm. That is, the offset structure 9 is formed by the connection points 6.4.2 of the second layer of threads formed by the second layer of threads 5.2 being offset from the connection points 6.4.1 of the first layer of threads formed by the first layer of threads 5.1.

[0066] It can be understood that the present embodiment adopts the wire dislocation structure 9 at the fourth type node 6.4, so that the height of the fourth type node 6.4 is consistent with the height of the grid edge line 5, which are both the superimposed heights of the two wires, thereby avoiding the risk of stress concentration and fracture of the blood vessel support structure due to the height difference between the fourth type node 6.4 and the grid edge line 5, and also avoiding the risk of damage to the inner wall of the blood vessel due to the poor adaptability of the blood vessel support structure at the blood vessel bend caused by the height of the fourth type node 6.4. In addition, as the height difference between the fourth type node 6.4 and the grid edge line 5 is reduced, the mechanical properties of the blood vessel support structure 1 are more uniform, and the uniformity of the overall wall of the blood vessel support structure is improved.

[0067] In other embodiments of the present invention, Figure 5As described, the first wire a and the second wire b are cross-connected to form the connection point 6.4.1 of the first layer of wires 5.1, the third wire c is superimposed on the second wire b, and at a position 1 mm away from the node 6.4.1 of the first layer of wires, the third wire c is bent into a parallel position at the same height as the second wire b, and extends 2 mm parallel to the second wire b, and then bends back again to be superimposed on the second wire; the fourth wire d is superimposed on the first wire a, and at a position 1 mm away from the connection point 6.4.1 of the first layer of wires, the fourth wire d is bent into a parallel position at the same height as the first wire a, and extends 2 mm parallel to the first wire a, and then crosses with the third wire c to form the connection point 6.4.2 of the second layer of wires 5.2, and then bends back again to be superimposed on the first wire a.

[0068] It can be understood that, according to the above-mentioned thread superposition method at the fourth type node 6.4, there is a first gap between the third thread c and the second thread b, and there is a second gap between the fourth thread d and the first thread a, so that the four threads together form a tic-tac-toe dislocation structure 9, and the tic-tac-toe connection structure further increases the support strength at the fourth type node 6.4. The size of the first gap and the second gap is 0.3-0.5mm.

[0069] Embodiment 3

[0070] Based on the vascular support structure of Example 1, the fourth type of node 6.4 described in this embodiment is formed by the intersection of four silk threads, and the four silk threads include a first silk thread a, a second silk thread b, a third silk thread c, and a fourth silk thread d that are printed and connected in sequence; the first silk thread a and the second silk thread b form a first layer of silk threads 5.1, and the third silk thread c and the fourth silk thread d form a second layer of silk threads 5.2.

[0071] The third wire c and the fourth wire d cross to form the connection point 6.4.2 of the second layer of wires 5.2, and the first wire a and the second wire b cross to form the connection point 6.4.1 of the first layer of wires 5.1. The connection point 6.4.2 of the second layer of wires 5.2 is superimposed on the connection point 6.4.1 of the first layer of wires 5.1, so that the height of the fourth type of node 6.4 is the superimposed height of the four wires.

[0072] Embodiment 4

[0073] Based on the vascular support structure of the first embodiment, the third type of nodes in the vascular support structure of this embodiment are designed with arc-shaped or ring-shaped connection points.

[0074] The third type of node 6.3 of the present invention is the connection point of two grids adjacent to the two end regions 8.1 and / or 8.2 and the bending region 7 of the vascular support structure 1, which is formed by two crossed wires and one bent wire, that is, the height of the third type of node 6.3 is the height of the superimposed wire diameter of the three wires. The third type of node 6.3 is the intersection of the bending region 7 where the grid edge line is a double-layer wire and the end region 8.1 and / or 8.2 where the grid edge line is a single-layer wire, so there may be a risk of unstable connection due to the height difference.

[0075] like Figure 6 As shown, the third type of node 6.3 described in this embodiment is the connection point of two adjacent grids of the end area 8.1 and the bending area 7, which is formed by two crossed wires (a and b) and a bent wire c, wherein the bent wire c is superimposed on the second wire b; the first wire a and the second wire b are the first layer of wires 5.1, and the bent wire c is the second layer of wires 5.2; the first wire a and the second wire b cross to form the connection point 6.4.1 of the first layer of wires 5.1.

[0076] In order to ensure the stable connection between the end region 8.1 and the curved region 7, the bent wire c located in the second layer is designed as an arc structure 10 that partially surrounds the connection point 6.4.1 of the first layer of wires 5.1. This arc structure 10 may be a semicircular, annular or other arc curve. This design avoids the height difference at the connection between the end region 8.1 and the curved region 7, ensuring the overall mechanical uniformity of the vascular support structure 1. This arc or annular structure also increases the connection strength at the third type of node 6.3 and reduces the concentrated stress at this location.

[0077] Embodiment 5

[0078] Based on the artificial blood vessel of the first embodiment, the bending area 7 of the blood vessel support structure 1 described in this embodiment can be divided into two parts, such as Figure 7 As shown, specifically, the first bending area 7.1 and the second bending area 7.2 along the circumferential direction, and further by adjusting the distance between the nozzle and the layer wire, the average superimposed wire height of the first bending area 7.1 is greater than the average superimposed wire height of the second bending area 7.2. The first bending area 7.1 can provide stronger support and pressure resistance, the second bending area 7.2 has better flexibility and compliance, and the design of different thicknesses enables the vascular support structure to bend in a predetermined direction after implantation, the outer side of the bend with a smaller average superimposed wire height has better flexibility, and the inner side of the bend with a larger average superimposed wire height has stronger support performance. This design enables the vascular support structure to bend in a directional manner in the body, and has better stability after implantation.

[0079] The average superimposed wire height of the first curved area 7.1 is 1.2-1.5 times the wire diameter of the 3D printing wire, and the average superimposed wire height of the second curved area 7.2 is 1.5-1.8 times the wire diameter of the 3D printing wire.

[0080] Embodiment 6

[0081] Based on the vascular support structure of Example 5, the vascular support structure described in this embodiment is provided with a display structure for displaying the position of the area in the first bending area 7.1 and the second bending area 7.2, so that the doctor can accurately locate the position of the vascular support structure, especially in a complex curved vascular anatomical structure, which is more conducive to the doctor's placement and adjustment of the curved part of the vascular support structure.

[0082] Embodiment 7

[0083] Based on the blood vessel support structure of Example 5, at least part of the mesh edge line 5 of the second curved area 7.2 of the blood vessel support structure described in this embodiment has an elastic structure, and the elastic structure is a curved structure. In this embodiment, at least part of the mesh edge line 5 of the second curved area 7.2 is designed to be an elastic curve shape. While increasing flexibility, the elastic edge line can be slightly deformed under blood flow pressure, which helps to maintain a more stable blood flow pattern and reduce the formation of turbulence and eddy currents.

[0084] Embodiment 8

[0085] Based on the blood vessel support structure of embodiment 1, Figure 8 As shown, in the bending area 7, the number of nodes along the cross section of the node 6 is 2, that is, the number of nodes in the bending area is 2; in the two end areas 8.1 and 8.2, the number of nodes along the cross section of the node 6 is also 2, that is, the number of nodes in the first end area 8.1 and the second section area 8.2 is also 2. Among them, radially adjacent closed loops share one node 6.

[0086] Embodiment 9

[0087] This embodiment provides an artificial blood vessel, such as Fig. 9 As shown, the artificial blood vessel comprises: an artificial blood vessel inner layer 2, a blood vessel support structure 1 and an artificial blood vessel outer layer 3 which are arranged in sequence from the inside to the outside.

[0088] The inner layer material of the artificial blood vessel is an anticoagulant biological material, a polymer material with inert modification, acellular extracellular matrix, or a polymer material with anticoagulant modification; the skeleton layer material is a polymer material or a composite material; and the outer layer material of the artificial blood vessel is a polyurethane material, silica gel, expanded polytetrafluoroethylene, or nylon elastomer material.

[0089] The artificial blood vessel inner layer and the artificial blood vessel outer layer are prepared by one or more methods such as 3D printing, electrospinning, casting, etc.

[0090] The artificial blood vessel has good bending performance and strong supporting force at the bent part, can adapt to different anatomical structures and blood vessel directions, and is not prone to bending at the bent part.

[0091] In other embodiments of the present invention, the width of the first layer of threads in the double layer of threads is greater than the width of the second layer of threads, thereby providing better supporting performance for the skeleton layer.

[0092] In other embodiments of the present invention, the width of the first layer of threads in the double layer of threads is greater than the width of the second layer of threads, thereby providing better supporting performance for the skeleton layer.

[0093] In other embodiments of the present invention, the number of nodes in the end region is greater than the number of nodes in the bending region.

[0094] The preferred embodiments of the present application are described in detail above, but the present application is not limited thereto. Within the technical concept of the present application, the technical solution of the present application can be subjected to a variety of simple modifications, including combining various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed in the present application and belong to the protection scope of the present application.

Claims

1. A vascular support structure, which is a grid-type vascular support structure formed by 3D printing, wherein the grid-type vascular support structure comprises a plurality of grids formed by 3D printing threads in the same direction or in a cross-spiral printing, each grid comprising four grid edges and four grid nodes, and the number of nodes along the cross section of the corresponding node is the number of nodes in the corresponding area of ​​the grid-type skeleton; The grid-type vascular support structure is axially divided into three regions, including a bending region located in the middle of the grid-type vascular support structure, and end regions arranged on both sides of the bending region and adjacent to and connected to the bending region; the number of nodes in the bending region is 1-3; Features: At least part of the mesh edges of the curved area are double-layer edges printed along the same path so as to overlap each other, and the mesh edges of the end area are single-layer edges; The double-layer edge line includes a first layer of wires and a second layer of wires, the cross-section of the first layer of wires and the second layer of wires after superposition is an oblate shape connected to each other, the height after superposition is the superimposed wire height of the first layer of wires and the second layer of wires, and the average superimposed wire height of the bending area is 1.2-1.8 times the wire diameter of the 3D printing wire; The nodes include four types of nodes, namely, first-type nodes, second-type nodes, third-type nodes, and fourth-type nodes; the first-type nodes are boundary nodes of the grid-type vascular support structure, which are formed by bending a silk thread; the second-type nodes are connection points of adjacent grids in the end area of ​​the grid-type vascular support structure, which are formed by crossing two silk threads; the third-type nodes are connection points of two adjacent grids in the end area and the curved area of ​​the grid-type vascular support structure, which are formed by two crossed silk threads and a bent silk thread; the fourth-type nodes are connection points of adjacent grids in the curved area of ​​the grid-type vascular support structure, which are formed by crossing four silk threads.

2. The vascular support structure according to claim 1, characterized in that: The fourth type of nodes have a dislocation structure, and the dislocation structure is formed by the connection points formed by the intersection of the second layer of silk threads deviating from the connection points formed by the intersection of the first layer of silk threads.

3. The blood vessel support structure according to claim 2, characterized in that: The dislocation structure at the fourth type of node includes four silk threads that are printed and connected in sequence, wherein the second silk thread is cross-connected to the first silk thread to form a connection point of the first layer of silk threads, the third silk thread is superimposed on the second silk thread at the edge line position, and the fourth silk thread is superimposed on the first silk thread at the edge line position. At the fourth type of node position, the third silk thread is bent into a parallel position at the same height as the second silk thread and cross-connected with the first silk thread, the fourth silk thread is bent away from the first silk thread and cross-connected with the second silk thread and the third silk thread, and the fourth silk thread and the third silk thread form a connection point of the second layer of silk threads; The offset distance between the connection points of the first layer of threads and the connection points of the second layer of threads is 0.3-0.5 mm.

4. The blood vessel support structure according to claim 3, characterized in that: At the fourth type of node position, there is a first gap between the third wire and the second wire, and a second gap between the fourth wire and the first wire, thereby forming a tic-tac-toe connection node; the size of the first gap and the second gap is 0.3-0.5mm.

5. The blood vessel support structure according to claim 1, characterized in that: The connection points formed by the crossing of the second layer of threads are superimposed on the connection points formed by the crossing of the first layer of threads.

6. The vascular support structure according to any one of claims 1 to 5, characterized in that: At the third type of node, the second silk thread is cross-connected to the first silk thread to form a connection point of the first layer of silk threads, and the third silk thread is superimposed on the second silk thread at the edge position. At the third type of node position, the third silk thread is bent into an arc or annular connection structure around the connection point of the first layer of silk threads, and is finally superimposed on the first silk thread.

7. The vascular support structure according to any one of claims 1 to 5, characterized in that: The bending region includes a first bending region and a second bending region along a circumferential direction, wherein an average superimposed wire height of the first bending region is greater than an average superimposed wire height of the second bending region.

8. The blood vessel support structure according to claim 7, characterized in that: A developing structure for displaying a region position is disposed in the first bending region or the second bending region.

9. The blood vessel support structure according to claim 7, characterized in that: At least part of the grid edge lines of the second curved area have an elastic structure, and the elastic structure is a curved structure.

10. The blood vessel support structure according to claim 7, characterized in that: The average superimposed wire height of the first bending area is 1.2-1.5 times the wire diameter of the 3D printing wire, and the average superimposed wire height of the second bending area is 1.5-1.8 times the wire diameter of the 3D printing wire.

11. The blood vessel support structure according to any one of claims 1 to 5, characterized in that: The width of the first layer of threads in the double-layer edge line is greater than the width of the second layer of threads.

12. The blood vessel support structure according to any one of claims 1 to 5, characterized in that: The number of nodes in the end region is greater than the number of nodes in the curved region.

13. An artificial blood vessel, comprising: An artificial blood vessel inner layer, a skeleton layer and an artificial blood vessel outer layer are arranged in sequence from the inside to the outside, and the skeleton layer is the blood vessel support structure according to any one of claims 1-12.

14. The artificial blood vessel according to claim 13, characterized in that: The inner layer of the artificial blood vessel is an anticoagulant biological material, a polymer material with an inert modification, a decellularized extracellular matrix, or a polymer material with an anticoagulant modification; the skeleton layer is a polymer material or a composite material; and the outer layer of the artificial blood vessel is a polyurethane material, silica gel, expanded polytetrafluoroethylene, or a nylon elastomer material.

15. The artificial blood vessel according to claim 13, characterized in that: The artificial blood vessel inner layer and the artificial blood vessel outer layer are prepared by combining one or more methods including 3D printing, electrospinning and casting.

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