A peripheral vascular stent

Abstract

This invention provides a peripheral vascular stent, which is a tubular structure comprising, from the inside out, a stent body, a polymer coating, and a drug coating. The stent body includes transition regions at both ends and a support region in the middle along the axial direction. The support region includes at least one double-crown structure and a first bridging structure. In the double-crown structure, the first peak of a first sine wave and the first trough of an adjacent first sine wave are spirally arranged circumferentially, with an axial angle that is a multiple of 15°; or, the first peak of the first sine wave and the first peak of an adjacent first sine wave are spirally arranged circumferentially, with an axial angle that is a multiple of 15°. The peripheral vascular stent provided by this invention can better adapt to vascular deformation, improve fracture resistance, and avoid restenosis caused by stent fracture; simultaneously, the drug coating on the outer surface can inhibit cell proliferation.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a peripheral vascular stent. Background Technology

[0002] Peripheral stent placement angioplasty is one of the endovascular treatment methods for FPA stenosis or occlusion lesions. Its purpose is to improve the blood supply to the lower limb arteries and relieve symptoms such as intermittent claudication and rest pain caused by lower limb ischemia.

[0003] However, in-stent restenosis (FPA-ISR) can occur after stent placement. Literature reports that the incidence of restenosis or occlusion after stent placement is as high as 20%-50%. Furthermore, the arteries of the lower limbs have unique physiological, pathological, biomechanical, and hydrodynamic characteristics. Poulson et al. reported that FPAs can exhibit 9%-25% axial compression and a bending radius of 8-27 mm during limb flexion, while Desyatova et al. reported that FPAs can exhibit tortuosity of 8° / cm-26° / cm under different postures.

[0004] However, existing peripheral vascular stents cannot fully meet the unique requirements of the lower extremity arteries. Furthermore, after stent treatment, more than 40% of patients with lower extremity arterial disease will experience in-stent restenosis due to chronic stent expansion force and low in-stent shear force.

[0005] Therefore, vascular stents must have good compressibility, delivery flexibility and expansion uniformity, which places very high demands on the material and structural design of vascular stents. Existing stents cannot yet achieve a perfect balance of these technical indicators.

[0006] Therefore, how to provide a vascular stent that can achieve a perfect balance of compressibility, delivery flexibility, and uniform expansion has become an urgent problem to be solved. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a peripheral vascular stent that achieves a perfect balance of compressibility, delivery flexibility, and uniform expansion.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] The present invention provides a peripheral vascular stent, which is a tubular structure and comprises, from the inside to the outside, a stent body, a polymer coating, and a drug coating; the stent body includes transition regions at both ends and a support region in the middle along the axial direction.

[0010] The support area includes at least one double crown and a first bridging body; the first bridging body connects two adjacent double crowns; the double crown includes two columns of first sine waves evenly distributed circumferentially; each column of first sine waves in the double crown includes a first peak, a first trough and a first support located between the first peak and the first trough;

[0011] The first peak of the first sine wave in the double crown and the first trough of the adjacent first sine wave are arranged in a spiral in the circumferential direction, and the included angle in the axial direction is a multiple of 15°, such as 15°, 30°, 45°, 60°, 75°, 90°, etc.

[0012] Alternatively, the first peak of the first sine wave in the double crown is arranged in a spiral in the circumferential direction with the first peak of the adjacent first sine wave, and the included angle in the axial direction is a multiple of 15°, such as 15°, 30°, 45°, 60°, 75°, 90°, etc.

[0013] In this invention, the angle between the first peak of the first sine wave in the double crown and the first trough of the adjacent first sine wave along the axis is 30°; or, the angle between the first peak of the first sine wave in the double crown and the first peak of the adjacent first sine wave along the axis is 30°.

[0014] Preferably, the first peak of the first sine wave in the double crown is connected to the first trough of the adjacent first sine wave through a first connector; and the first peak and first trough at both ends of the first connector are adjacent or not adjacent to the first peak and first trough at both ends of the adjacent first connector; or, the first peak of the first sine wave in the double crown is connected to the first peak of the adjacent first sine wave through a first connector; and the first peak at both ends of the first connector are adjacent or not adjacent to the first peak at both ends of the adjacent first connector.

[0015] Preferably, the two adjacent first connecting bodies in the support area can be in the same direction or in opposite directions.

[0016] Preferably, the first bridging body and the first connecting body in the support area are the same or different.

[0017] In this invention, the accompanying drawings, from left to right, depict the distal to proximal ends of the support body. The first peak at the distal end of the double crown is connected to the first trough at the proximal end of the adjacent first sine wave via a first connector. The first peak at the distal end is spaced between adjacent first connectors in the double crown, and the first trough at the proximal end is spaced between adjacent first connectors; the number of distal first peaks and / or the number of proximal first troughs are constant values.

[0018] In this invention, the first sine wave in the double crowns of the support area is arranged in a spiral, and the first connecting body is a relatively long structure and forms a certain angle with the axis, thereby improving the torsional performance of the support; the first bridging body between adjacent double crowns is parallel to the axis, providing the support with the ability to resist shortening.

[0019] In this invention, from the axial direction of the main body, the second bridging body in the transition zone has good flexibility, the first connector in the double coronary body has good torsional flexibility, and the first bridging body between the double coronary bodies has anti-shortening ability, enabling the entire stent to better adapt to the deformation of the blood vessel, improve its anti-fracture ability, and avoid restenosis caused by stent fracture. At the same time, the drug coating on the outer surface can inhibit cell proliferation, reducing the restenosis problem caused by stent fracture and endothelial cell proliferation in previous products. This dual protection solves the problem of high long-term restenosis rate of peripheral stents.

[0020] In this invention, the transition zone includes a closed loop and a second bridging body; the second bridging body connects the transition zone and the support zone.

[0021] In this invention, the transition zone includes a closed loop and a second bridging body. The closed loop facilitates stent gripping and delivery, and also facilitates stent anchoring. The second bridging body connects the transition zone and the support zone, providing better flexibility and making it easier for the stent to adapt to the curvature of blood vessels caused by limb flexion.

[0022] Preferably, the closed loop comprises at least two columns of second sine waves uniformly distributed circumferentially.

[0023] Preferably, each second sine wave in the closed loop includes a second peak, a second trough, and a second support located between the second peak and the second trough.

[0024] Preferably, the second trough of the second sine wave in the closed loop is aligned axially with the second peak of the adjacent second sine wave.

[0025] Preferably, the second trough of the second sine wave in the closed loop is connected to the second peak of the adjacent second sine wave through a second connector.

[0026] In this invention, the figures show the support body from left to right, from the far end to the near end. The second trough at the far end of the closed loop is connected to the second peak at the near end of the adjacent second sine wave through a second connector.

[0027] Preferably, the second bridging body in the transition zone is the same as or different from the first bridging body and the first connecting body in the support zone.

[0028] In this invention, the diameter of the transition zone is greater than or equal to the diameter of the support zone.

[0029] In this invention, the drug coating can inhibit cell proliferation and effectively reduce restenosis. The diameter of the transition zone is greater than or equal to the diameter of the support zone, facilitating the anchoring of the two ends of the stent.

[0030] Preferably, the thickness of the support body is 0.1-0.3mm (e.g., 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, etc.).

[0031] Preferably, the thickness of the polymer coating is 1-10 μm (e.g., 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, etc.), and more preferably 2-4 μm (e.g., 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, etc.).

[0032] Preferably, the thickness of the drug coating is 1-10 μm (e.g., it can be 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, etc.), and more preferably 4-6 μm (e.g., it can be 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, etc.).

[0033] In this invention, the shape of the second bridging body in the transition zone is selected from a straight type or a curved type, wherein the curved type includes any one or a combination of at least two of the following: S-shaped, V-shaped, N-shaped, Ω-shaped, Z-shaped or spiral.

[0034] Preferably, the shape of the second connector in the closed loop is selected from a straight or curved shape, and the curved shape includes any one or a combination of at least two of the following: S-shaped, V-shaped, N-shaped, Ω-shaped, Z-shaped or spiral.

[0035] Preferably, the shape of the second support in the second sine wave of the closed loop is selected from a straight or curved shape, and the curved shape includes any one or a combination of at least two of the following: S-shaped, V-shaped, N-shaped, Ω-shaped, Z-shaped or spiral.

[0036] In this invention, the width of the second peak in the second sine wave of the closed loop is greater than the width of the second support; the width of the second trough in the second sine wave of the closed loop is greater than the width of the second support.

[0037] Preferably, in the second sine wave of the closed loop, the width of the second support is greater than or equal to the width of the second connector.

[0038] In this invention, the number of second connectors in the closed loop is equal to the number of second troughs in the circumferential direction.

[0039] Preferably, the number of second connectors in the closed loop is greater than the number of second bridges.

[0040] Preferably, the number of second connectors in the closed loop is twice the number of second bridges.

[0041] In this invention, the shape of the first bridging body in the support area is selected from a straight or curved shape, and the curved shape includes any one or a combination of at least two of the following: S-shaped, V-shaped, N-shaped, Ω-shaped, Z-shaped or spiral.

[0042] Preferably, the first connectors in the double crown are evenly distributed circumferentially, and the number of the first connectors is 3-6 (for example, 3, 4, 5, 6, etc.), preferably 3.

[0043] Preferably, the length of the first connector in the double crown is greater than the length of the first support, and the length of the first support is greater than the length of the first bridging body.

[0044] In this invention, the material of the support body is selected from any one or a combination of at least two of nickel-titanium alloy, cobalt-chromium alloy, stainless steel or biodegradable polymer materials.

[0045] Preferably, the polymer in the polymer coating is selected from polylactic-co-hydroxyacetic acid and its derivatives or polybutyl methacrylate and its derivatives.

[0046] In this invention, the drug coating is a polymer coating containing a drug.

[0047] Preferably, the drug includes any one or a combination of at least two of the following: statins, rapamycin, paclitaxel, and heparin.

[0048] Preferably, the polymer carrier in the polymer coating containing the drug comprises any one or a combination of at least two of the following: polylactic acid and its derivatives, polylactic acid-glycolic acid, choline phosphate, polyvinylidene fluoride hexafluoropropylene copolymer, polyacrylate, lactide-aspartic acid derivative copolymer, polybutyl methacrylate, vinylidene fluoride-hexafluoropropylene, Parylene C (parxylene), BioLinx polymer (parxylene-polyvinylpyrrolidone), or styrene-isobutylene copolymer.

[0049] In this invention, the stent body is formed with a transition zone and a support zone by laser cutting. The stent body formed after laser cutting undergoes heat treatment to achieve the required shape and size, and surface burrs are removed through an electrochemical polishing process to create a smooth surface. A polymer coating is applied to the surface of the stent body; the polymer coating may also contain a drug. A drug coating is applied to the surface of the polymer coating.

[0050] The application method of the polymer coating and the drug coating is selected from one or a combination of at least two of the following: spraying, dipping, dripping, or rolling.

[0051] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0052] The peripheral vascular stent provided by this invention can better adapt to the deformation of blood vessels, improve its resistance to fracture, and avoid restenosis caused by stent fracture. At the same time, the drug coating on the outer surface can inhibit cell proliferation, reducing the restenosis problem caused by stent fracture and endothelial cell proliferation in previous products. This dual protection solves the problem of high long-term restenosis rate of peripheral stents. Attached Figure Description

[0053] Figure 1 This is an overall schematic diagram of the peripheral vascular stents provided in Examples 1, 2, and 3;

[0054] Among them, 1 is the stent body, 2 is the polymer coating, and 3 is the drug coating.

[0055] Figure 2 This is an enlarged schematic diagram of the stent body 1 in the peripheral vascular stent provided in Example 1;

[0056] Among them, 11 is the transition zone, 111 is the closed loop, 112 is the second bridging body; 12 is the support zone, 121 is the double crown body, and 122 is the first bridging body.

[0057] Figure 3 This is an enlarged schematic diagram of the double coronary body 121 in the peripheral vascular stent provided in Example 1;

[0058] Among them, 1211 is the first sine wave, and 1212 is the first connecting body.

[0059] Figure 4 An enlarged schematic diagram of the first sine wave 1211 in the double coronary body 121 of the peripheral vascular stent provided in Examples 1, 2 and 3;

[0060] Among them, 12111 is the first peak, 12112 is the first trough, and 12113 is the first support.

[0061] Figure 5 An enlarged schematic diagram of the closed loop 111 in the peripheral vascular stent provided in Examples 1, 2 and 3;

[0062] Among them, 1111 is the second sine wave, and 1112 is the second connecting body.

[0063] Figure 6 An enlarged schematic diagram of the second sine wave 1111 portion in the closed loop body 111 of the peripheral vascular stent provided in Examples 1, 2 and 3;

[0064] Among them, 11111 is the second peak, 11112 is the second trough, and 11113 is the second support.

[0065] Figure 7 This is an enlarged schematic diagram of the stent body 1 in the peripheral vascular stent provided in Example 2;

[0066] Among them, 11 is the transition zone, 111 is the closed loop, 112 is the second bridging body; 12 is the support zone, 121 is the double crown body, and 122 is the first bridging body.

[0067] Figure 8 An enlarged schematic diagram of the double coronary body 121 in the peripheral vascular stent provided in Examples 2 and 3;

[0068] Among them, 1211 is the first sine wave, and 1212 is the first connecting body.

[0069] Figure 9 An enlarged schematic diagram of the stent body 1 in the peripheral vascular stent provided in Example 3;

[0070] Among them, 11 is the transition zone, 111 is the closed loop, 112 is the second bridging body; 12 is the support zone, 121 is the double crown body, and 122 is the first bridging body. Detailed Implementation

[0071] It should be understood that in the description of this invention, the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0072] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0073] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0074] Example 1

[0075] This embodiment provides a peripheral vascular stent.

[0076] like Figure 1 As shown, the peripheral vascular stent is a tubular structure, and from the inside out, the peripheral vascular stent includes a stent body 1 (thickness 0.2 mm), a polymer coating 2 (thickness 3 μm), and a drug coating 3 (thickness 5 μm).

[0077] like Figure 2 As shown, the support body 1 includes transition zones 11 at both ends and a support zone 12 in the middle along the axial direction; the diameter of the transition zone 11 is equal to the diameter of the support zone 12. The support zone 12 includes double crowns 121 and a first bridging body 122 (straight type); the first bridging body 122 connects two adjacent double crowns 121.

[0078] like Figure 3 and Figure 4 As shown, the double crown 121 includes two columns of first sine waves 1211 evenly distributed circumferentially. Each column of first sine waves 1211 in the double crown 121 includes a first peak 12111, a first trough 12112, and a first support 12113 located between the first peak 12111 and the first trough 12112. The first peak 12111 and the first trough 12112 of the first sine waves 1211 in the double crown 121 are spirally arranged circumferentially with an included angle α of 30° in the axial direction.

[0079] like Figure 3 and Figure 4 As shown, the first peak 12111 of the first sine wave 1211 in the double crown 121 is connected to the first valley 12112 of the adjacent first sine wave 1211 by the first connector 1212; and the first peak 12111 and the first valley 12112 at both ends of the first connector 1212 are not adjacent to the first peak 12111 and the first valley 12112 at both ends of the adjacent first connector 1212.

[0080] It should be noted that, as Figure 3 As shown, Figure 3 From left to right, the support body 1 is from the far end to the near end. The first peak 12111 at the far end of the double crown 121 is connected to the first trough 12112 at the near end of the adjacent first sine wave 1211 by the first connector 1212.

[0081] like Figure 2As shown, the transition zone 11 includes a closed loop 111 and a second bridging body 112 (straight type); the second bridging body 112 connects the transition zone 11 and the support zone 12.

[0082] like Figures 5-6 As shown, the closed-loop body 111 includes at least two columns of second sine waves 1111 evenly distributed circumferentially. Each column of second sine waves 1111 in the closed-loop body 111 includes a second peak 11111, a second trough 11112, and a second support 11113 (straight type) located between the second peak 11111 and the second trough 11112. The second trough 11112 of the second sine wave 1111 in the closed-loop body 111 is axially aligned with the second peak 11111 of the adjacent second sine wave 1111. The second trough 11112 of the second sine wave 1111 in the closed-loop body 111 is connected to the second peak 11111 of the adjacent second sine wave 1111 by the second connector 1112 (straight type).

[0083] like Figure 5 As shown, Figure 5 From left to right, the support body 1 is from the far end to the near end. The second trough 11112 at the far end of the closed loop 111 is connected to the second peak 11111 at the near end of the adjacent second sine wave 1111 through the second connector 1112.

[0084] The width of the second peak 1111 in the second sine wave 1111 of the closed loop 111 is greater than the width of the second support 11113; the width of the second trough 11112 in the second sine wave 1111 of the closed loop 111 is greater than the width of the second support 11113.

[0085] In the second sine wave 1111 of the closed loop 111, the width of the second support 11113 is greater than the width of the second connector 1112.

[0086] The number of second connectors 1112 in the closed loop 111 is equal to the number of second troughs 11112 in the circumferential direction.

[0087] The number of second connectors 1112 in the closed loop 111 is twice the number of second bridges 112.

[0088] The first connectors 1212 in the double crown 121 are evenly distributed circumferentially, and there are 3 first connectors 1212.

[0089] In the double crown 121, the length of the first connector 1212 is greater than the length of the first support 12113, and the length of the first support 12113 is greater than the length of the first bridging body 122.

[0090] The material of the support body 1 is selected from nickel-titanium alloy.

[0091] The polymer in the polymer coating 2 is selected from polybutyl methacrylate.

[0092] The drug coating 3 is a polymer coating containing a drug.

[0093] The drug is paclitaxel, and the polymer carrier is polyvinylidene fluoride hexafluoropropylene copolymer.

[0094] Example 2

[0095] This embodiment provides a peripheral vascular stent, which differs from Embodiment 1 in that the structure of the stent body 1 is different.

[0096] like Figure 7 As shown, the support body 1 includes a transition zone 11 at both ends and a support zone 12 in the middle along the axial direction; the diameter of the transition zone 11 is equal to the diameter of the support zone 12.

[0097] The transition zone 11 includes a closed loop 111 and a second bridging body 112; the second bridging body 112 connects the transition zone 11 and the support zone 12.

[0098] It should be noted that, Figure 7 From left to right, the main body of the support structure is from the far end to the near end. The second bridging body 112 at the far end is straight, while the second bridging body 112 at the near end is Z-shaped.

[0099] The support area 12 includes a double crown 121 and a first bridging body 122 (Z-shaped); the first bridging body 122 connects two adjacent double crowns 121.

[0100] like Figure 4 and Figure 8 As shown, the first peak 12111 of the first sine wave 1211 in the double crown 121 and the first peak 12111 of the adjacent first sine wave 1211 are spirally arranged in the circumferential direction, and the included angle β in the axial direction is 30°.

[0101] like Figure 8 As shown, the first peak 12111 of the first sine wave 1211 in the double crown 121 is connected to the first peak 12111 of the adjacent first sine wave 1211 through the first connector 1212; and the first peak 12111 at both ends of the first connector 1212 is not adjacent to the first peak 12111 at both ends of the adjacent first connector 1212.

[0102] It should be noted that, Figure 8 From left to right, the main body of the support is from the far end to the near end. The first peak 12111 at the far end of the double crown 121 is connected to the first peak 12111 at the near end of the adjacent first sine wave 1211 through the first connector 1212.

[0103] It should be noted that, as Figure 7 and Figure 8 As shown, the first bridging body 122 is in the same direction as the first connecting body 1212 in the adjacent double crown body 121, and the first bridging body 122 is in the same direction as the second bridging body 112 at the proximal end.

[0104] The other structures and compositions are the same as in Example 1.

[0105] Example 3

[0106] This embodiment provides a peripheral vascular stent, which differs from Embodiment 1 in that the structure of the stent body 1 is different.

[0107] This embodiment provides a peripheral vascular stent, which differs from Embodiment 1 in that the structure of the stent body 1 is different.

[0108] like Figure 9 As shown, the support body 1 includes a transition zone 11 at both ends and a support zone 12 in the middle along the axial direction; the diameter of the transition zone 11 is equal to the diameter of the support zone 12.

[0109] The transition zone 11 includes a closed loop 111 and a second bridging body 112; the second bridging body 112 connects the transition zone 11 and the support zone 12.

[0110] It should be noted that, Figure 9 From left to right, the main body of the support structure is from the far end to the near end. The second bridging body 112 at the far end is straight, while the second bridging body 112 at the near end is Z-shaped.

[0111] The support area 12 includes a double crown 121 and a first bridging body 122 (Z-shaped); the first bridging body 122 connects two adjacent double crowns 121.

[0112] like Figure 4 and Figure 8 As shown, the first peak 12111 of the first sine wave 1211 in the double crown 121 and the first peak 12111 of the adjacent first sine wave 1211 are spirally arranged in the circumferential direction, and the included angle β in the axial direction is 30°.

[0113] like Figure 8 As shown, the first peak 12111 of the first sine wave 1211 in the double crown 121 is connected to the first peak 12111 of the adjacent first sine wave 1211 through the first connector 1212; and the first peak 12111 at both ends of the first connector 1212 is not adjacent to the first peak 12111 at both ends of the adjacent first connector 1212.

[0114] It should be noted that, Figure 8From left to right, the main body of the support is from the far end to the near end. The first peak 12111 at the far end of the double crown 121 is connected to the first peak 12111 at the near end of the adjacent first sine wave 1211 through the first connector 1212.

[0115] It should be noted that, as Figure 8 and Figure 9 As shown, the first bridging body 122 is opposite to the first connecting body 1212 in the adjacent double crown body 121, and the first bridging body 122 is in the same direction as the second bridging body 112 at the proximal end.

[0116] The other structures and compositions are the same as in Example 1.

[0117] Example 4

[0118] This embodiment provides a peripheral vascular stent, which differs from Embodiment 1 only in that the diameter of the transition region 11 is larger than the diameter of the support region 12; the other components and structures are the same as in Embodiment 1.

[0119] Example 5

[0120] This embodiment provides a peripheral vascular stent, which differs from Embodiment 1 only in that the drug coating 3 is a polymer coating containing a drug, namely rapamycin, and the polymer carrier is polylactic acid; other components and structures are the same as in Embodiment 1.

[0121] Comparative Example 1

[0122] This comparative example provides a peripheral vascular stent, differing from Embodiment 1 only in that the first peak 12111 of the first sine wave 1211 in the double crown 121 is axially aligned with the first trough 12112 of the adjacent first sine wave 1211. The first peak 12111 of the first sine wave 1211 and the first trough 12112 of the adjacent first sine wave 1211 are connected by a first connector 1212. Other components and structures are the same as in Embodiment 1.

[0123] Test case

[0124] Test method: Finite element simulation of the support body 1 was performed using Abaqus software.

[0125] The results show that the maximum stress of the first connector 1212, which is connected at an angle (30°) in Example 1, is 457 MPa in the torsion simulation, while the maximum stress of the first connector 1212, which has no angle in the axial direction in Comparative Example 1, is 480 MPa in the finite element simulation. This proves that the first connector 1212, which is connected at an angle, can improve the torsional resistance of the main body 1.

[0126] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A peripheral vascular stent, characterized in that, The peripheral vascular stent is a tubular structure, and the peripheral vascular stent includes, from the inside to the outside, a stent body (1), a polymer coating (2) and a drug coating (3); the stent body (1) includes a transition region (11) at both ends and a support region (12) in the middle along the axial direction. The support area (12) includes at least one double crown (121) and a first bridging body (122); the first bridging body (122) connects two adjacent double crowns (121); the double crown (121) includes two columns of first sine waves (1211) evenly distributed along the circumference; each column of first sine waves (1211) in the double crown (121) includes a first peak (12111), a first trough (12112) and a first support body (12113) located between the first peak (12111) and the first trough (12112). The first peak (12111) of the first sine wave (1211) in the double crown (121) and the first trough (12112) of the adjacent first sine wave (1211) are arranged in a spiral in the circumferential direction, and the included angle (a) in the axial direction is 30°. Alternatively, the first peak (12111) of the first sine wave (1211) in the double crown (121) and the first peak (12111) of the adjacent first sine wave (1211) are arranged in a spiral in the circumferential direction, and the included angle (β) in the axial direction is 30°. The transition zone (11) includes a closed loop (111) and a second bridging body (112); the second bridging body (112) connects the transition zone (11) and the support zone (12). The shape of the first bridging body (122) in the support area (12) is selected from straight or curved, and the curved type includes any one or at least a combination of two of the following: S-shaped, V-shaped, N-shaped, Ω-shaped, Z-shaped or spiral. The first bridging body between adjacent double crowns is parallel to the axial direction; The first peak (12111) of the first sine wave (1211) in the double crown (121) is connected to the first trough (12112) of the adjacent first sine wave (1211) through the first connector (1212); or, the first peak (12111) of the first sine wave (1211) in the double crown (121) is connected to the first peak (12111) of the adjacent first sine wave (1211) through the first connector (1212). The first bridging body (122) in the support area (12) is different from the first connecting body (1212).

2. The peripheral vascular stent according to claim 1, characterized in that, The two adjacent first connecting bodies (1212) in the support area (12) can be in the same direction or in opposite directions.

3. The peripheral vascular stent according to claim 1, characterized in that, The closed loop (111) includes at least two columns of second sine waves (1111) that are uniformly distributed circumferentially.

4. The peripheral vascular stent according to claim 3, characterized in that, Each second sine wave (1111) in the closed loop (111) includes a second peak (11111), a second trough (11112), and a second support (11113) located between the second peak (11111) and the second trough (11112).

5. The peripheral vascular stent according to claim 4, characterized in that, The second trough (11112) of the second sine wave (1111) in the closed loop (111) is aligned axially with the second peak (11111) of the adjacent second sine wave (1111).

6. The peripheral vascular stent according to claim 4, characterized in that, The second trough (11112) of the second sine wave (1111) in the closed loop (111) is connected to the second peak (11111) of the adjacent second sine wave (1111) through the second connector (1112).

7. The peripheral vascular stent according to claim 1, characterized in that, The second bridging body (112) in the transition zone (11) may be the same as or different from the first bridging body (122) and the first connecting body (1212) in the support zone (12).

8. The peripheral vascular stent according to claim 1, characterized in that, The diameter of the transition region (11) is greater than or equal to the diameter of the support region (12).

9. The peripheral vascular stent according to claim 1, characterized in that, The thickness of the support body (1) is 0.1-0.3 mm.

10. The peripheral vascular stent according to claim 1, characterized in that, The thickness of the polymer coating (2) is 1-10 μm.

11. The peripheral vascular stent according to claim 10, characterized in that, The thickness of the polymer coating (2) is 2-4 μm.

12. The peripheral vascular stent according to claim 1, characterized in that, The thickness of the drug coating (3) is 1-10 μm.

13. The peripheral vascular stent according to claim 12, characterized in that, The thickness of the drug coating (3) is 4-6 μm.

14. The peripheral vascular stent according to claim 1, characterized in that, The shape of the second bridging body (112) in the transition zone (11) is selected from straight or curved, and the curved type includes any one or at least a combination of two of the following: S-shaped, V-shaped, N-shaped, Ω-shaped, Z-shaped or spiral.

15. The peripheral vascular stent according to claim 4, characterized in that, The shape of the second support (11113) in the second sine wave (1111) of the closed loop (111) is selected from a straight or curved shape, and the curved shape includes any one or at least a combination of two of the following: S-shaped, V-shaped, N-shaped, Ω-shaped, Z-shaped or spiral shape.

16. The peripheral vascular stent according to claim 6, characterized in that, The shape of the second connector (1112) in the closed loop (111) is selected from straight or curved, and the curved type includes any one or at least a combination of two of the following: S-shaped, V-shaped, N-shaped, Ω-shaped, Z-shaped or spiral.

17. The peripheral vascular stent according to claim 5, characterized in that, The width of the second peak (11111) in the second sine wave (1111) of the closed loop (111) is greater than the width of the second support (11113); the width of the second trough (11112) in the second sine wave (1111) of the closed loop (111) is greater than the width of the second support (11113).

18. The peripheral vascular stent according to claim 6, characterized in that, The width of the second support (11113) in the second sine wave (1111) of the closed loop (111) is greater than or equal to the width of the second connector (1112).

19. The peripheral vascular stent according to claim 6, characterized in that, The number of second connectors (1112) in the closed loop (111) is equal to the number of second troughs (11112) in the circumferential direction.

20. The peripheral vascular stent according to claim 6, characterized in that, The number of second connectors (1112) in the closed loop (111) is greater than the number of second bridges (112).

21. The peripheral vascular stent according to claim 6, characterized in that, The number of second connectors (1112) in the closed loop (111) is twice the number of second bridges (112).

22. The peripheral vascular stent according to claim 1, characterized in that, The first connector (1212) in the double crown (121) is evenly distributed along the circumference, and the number of the first connector (1212) is 3-6.

23. The peripheral vascular stent according to claim 22, characterized in that, The number of the first connectors (1212) is 3.

24. The peripheral vascular stent according to claim 1, characterized in that, In the double crown (121), the length of the first connector (1212) is greater than the length of the first support (12113), and the length of the first support (12113) is greater than the length of the first bridge (122).

25. The peripheral vascular stent according to any one of claims 1-24, characterized in that, The material of the support body (1) is selected from any one or a combination of at least two of nickel-titanium alloy, cobalt-chromium alloy, stainless steel or biodegradable polymer materials.

26. The peripheral vascular stent according to any one of claims 1-24, characterized in that, The polymer in the polymer coating (2) is selected from polylactic acid-hydroxyacetic acid and its derivatives or polybutyl methacrylate and its derivatives.

27. The peripheral vascular stent according to any one of claims 1-24, characterized in that, The drug coating (3) is a polymer coating containing a drug.

28. The peripheral vascular stent according to claim 27, characterized in that, The drugs include any one or a combination of at least two of the following: statins, rapamycin, paclitaxel, and heparin.

29. The peripheral vascular stent according to claim 27, characterized in that, The polymer carrier in the polymer coating containing the drug includes any one or a combination of at least two of the following: polylactic acid and its derivatives, polylactic-co-hydroxyacetic acid, choline phosphate, polyvinylidene fluoride hexafluoropropylene copolymer, polyacrylate, lactide-aspartic acid derivative copolymer, polybutyl methacrylate, vinylidene fluoride-hexafluoropropylene, parylene, parylene-polyvinylpyrrolidone or styrene-isobutylene copolymer.

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