Stent structure and medical stent

Abstract

According to the stent structure and the medical stent, a first interval stent section and a second interval stent section are connected with the two ends of a middle stent section respectively, a first end stent section is connected with the end of the first interval stent section, and a second end stent section is connected with the end of the second interval stent section; the first end stent section and the second end stent section have first stent body flexibility, the first interval stent section and the second interval stent section have second stent body flexibility, the middle stent section has third stent body flexibility, the first stent body flexibility is smaller than the second stent body flexibility, and the second stent body flexibility is smaller than the third stent body flexibility. The stent structure is divided into five sections, the flexibility of each section can be designed in a targeted mode, the fatigue resistance and the long-term patency rate of the stent structure are improved, the stent structure conforms to various composite stress conditions such as bending, torsion, compression and extrusion of peripheral blood vessels, and the risks of blood vessel damage and stent breakage caused by poor compliance of the stent structure are reduced.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to a stent structure and a medical stent. Background Art

[0002] Cardiovascular diseases seriously affect people's health. Vascular prostheses such as stents are widely used in the treatment of various abnormalities in human vascular pathways, such as hemangiomas, dissections, embolism, stenosis, etc. Laser-cut stents have been widely used in the intracavitary treatment of various vascular diseases due to their flexible designability. In clinical applications, the use of stents has significantly improved the patency of blood vessels and effectively improved the clinical effects of patients. However, there are still problems such as irritation of healthy blood vessels, poor flexibility, poor stent release morphology, poor fatigue fracture resistance, and restenosis in the stent.

[0003] In order to solve the above problems, drug-eluting stents have emerged. Drug-eluting stents are a kind of stents that apply a specific coating to the surface of the stent in a specific way. When the stent is placed in the lesion site, the drug is eluted from the stent in a controllable manner, thereby inhibiting the proliferation of the intimal membrane and further improving the late patency of the blood vessels. The drugs used include rapamycin and paclitaxel, which can inhibit the proliferation and migration of smooth muscle cells. However, due to the influence of complex movements such as bending, twisting, compression, and extrusion on the arterial blood vessels of the human body, the stent is subjected to poor stress conditions, which can easily cause the stent to break, causing restenosis of the blood vessels and reducing the patency of the blood vessels. Since the stent end is anchored in the healthy blood vessel, the stimulation of the stent end to the healthy blood vessel will also affect the long-term patency of the blood vessel. In addition, if the stent release morphology is not good, the stent will be in a stress state for a long time, reducing the fatigue resistance of the stent, increasing the stent breakage rate, and reducing the long-term patency of the blood vessel. Utility Model Content

[0004] Based on this, it is necessary to provide a support structure and a medical support to address at least one of the technical problems mentioned above.

[0005] The present application provides a support structure, the support structure comprising:

[0006] middle bracket segment;

[0007] a first spaced support segment and a second spaced support segment, wherein the first spaced support segment and the second spaced support segment are respectively connected to two ends of the middle support segment;

[0008] A first end bracket segment and a second end bracket segment, wherein the first end bracket segment is connected to an end of the first interval bracket segment, and the second end bracket segment is connected to an end of the second interval bracket segment;

[0009] At least one of the first end bracket segment and the second end bracket segment has a first frame flexibility, at least one of the first interval bracket segment and the second interval bracket segment has a second frame flexibility, and the middle bracket segment has a third frame flexibility, the first frame flexibility is less than the second frame flexibility, and the second frame flexibility is less than the third frame flexibility.

[0010] In one embodiment, the first end bracket segment comprises a plurality of first bracket unit rings, the first bracket unit rings have a plurality of first wave crests and first wave troughs arranged in sequence in the circumferential direction, the plurality of first bracket unit rings are arranged along the axial direction of the first end bracket segment, and the first wave crests and the first wave troughs which are closest in axial distance among adjacent first bracket unit rings are connected; and / or,

[0011] The second end bracket segment comprises a plurality of second bracket unit rings, the second bracket unit rings have a plurality of second wave crests and second wave troughs arranged in sequence in the circumferential direction, the plurality of second bracket unit rings are arranged along the axial direction of the second end bracket segment, and the second wave crests and the second wave troughs in adjacent second bracket unit rings that are closest in axial direction are connected; and / or,

[0012] The first spaced support segment comprises a plurality of third support unit rings, the third support unit rings have a plurality of third wave crests and third wave troughs arranged in sequence in the circumferential direction, the plurality of third support unit rings are arranged along the axial direction of the first spaced support segment, and the third wave crests and the third wave troughs of the parts of adjacent third support unit rings that are closest in axial direction are connected; and / or,

[0013] The second spaced support segment comprises a plurality of fourth support unit rings, the fourth support unit rings having a plurality of fourth wave crests and fourth wave troughs spaced in sequence in the circumferential direction, the plurality of fourth support unit rings being arranged along the axial direction of the second spaced support segment, and the fourth wave crests and the fourth wave troughs of the parts of adjacent fourth support unit rings that are closest in axial direction are connected; and / or,

[0014] The middle support segment includes a plurality of fifth support unit rings, each of which has a plurality of fifth wave crests and fifth wave troughs arranged in sequence in the circumferential direction. The plurality of fifth support unit rings are arranged along the axial direction of the middle support segment, and the fifth wave crests of the adjacent fifth support unit rings that are closest in axial distance are connected.

[0015] In one embodiment, adjacent first wave crests and first wave troughs are connected by a first connecting element; wherein a straight line between the connected first wave crests and the first wave troughs is parallel to the axis of the first end bracket segment, or a straight line between the connected first wave crests and the first wave troughs has an angle with the axis of the first end bracket segment; and / or,

[0016] Adjacent second wave crests and second wave troughs are connected by a second connecting element; wherein a straight line between the connected second wave crests and second wave troughs is parallel to the axis of the second end bracket segment, or a straight line between the connected second wave crests and second wave troughs has an angle with the axis of the second end bracket segment; and / or,

[0017] The adjacent third wave crests and the third wave troughs are connected via a third connecting element; wherein a straight line between the connected third wave crests and the third wave troughs is parallel to the axis of the first spaced support segment, or a straight line between the connected third wave crests and the third wave troughs has an angle with the axis of the first spaced support segment; and / or,

[0018] The adjacent fourth wave crests and the fourth wave troughs are connected via a fourth connecting element; wherein a straight line between the connected fourth wave crests and the fourth wave troughs is parallel to the axis of the second spaced support segment, or a straight line between the connected fourth wave crests and the fourth wave troughs forms an angle with the axis of the second spaced support segment; and / or,

[0019] Part of the fifth wave peaks in adjacent fifth bracket unit rings are connected by a fifth connecting element; wherein, a straight line between the connected fifth wave peaks is parallel to the axis of the middle bracket segment, or a straight line between the connected fifth wave peaks has an angle with the axis of the middle bracket segment.

[0020] In one embodiment, a straight line between the first wave crests and the first wave troughs connected to each other has an angle with the axis of the first end bracket segment, so that the first wave crests and the first wave troughs connected to each other have a first offset distance in the circumferential direction of the first end bracket segment, and the first offset distance is smaller than a straight-line distance between the first wave crests and the first wave troughs connected to each other; and / or,

[0021] A straight line between the connected second wave crests and the second wave troughs has an included angle with the axis of the second end bracket segment, so that the connected second wave crests and the second wave troughs have a second offset distance in the circumferential direction of the second end bracket segment, and the second offset distance is smaller than a straight-line distance between the connected second wave crests and the second wave troughs; and / or,

[0022] A straight line between the connected third wave crests and the third wave troughs has an included angle with the axis of the first spaced support segment, so that the connected third wave crests and the third wave troughs have a third offset distance in the circumferential direction of the first spaced support segment, and the third offset distance is smaller than a straight-line distance between the connected third wave crests and the third wave troughs; and / or,

[0023] A straight line between the connected fourth wave peaks and the fourth wave valleys has an angle with the axis of the second interval bracket segment, so that the connected fourth wave peaks and the fourth wave valleys have a fourth offset distance in the circumferential direction of the second interval bracket segment, and the fourth offset distance is smaller than the straight-line distance between the connected fourth wave peaks and the fourth wave valleys.

[0024] In one embodiment, the first connecting element is at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod or an Ω-shaped rod;

[0025] And / or, the second connecting element is at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod or an Ω-shaped rod;

[0026] And / or, the third connecting element is at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod or an Ω-shaped rod;

[0027] And / or, the fourth connecting element is at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod or an Ω-shaped rod;

[0028] And / or, the fifth connecting element is at least one of a linear rod, an S-shaped rod, a V-shaped rod, an N-shaped rod or an Ω-shaped rod.

[0029] In one embodiment, adjacent third bracket unit rings have multiple pairs of third wave crests and third wave troughs that cooperate with each other in the axial direction of the first spaced bracket segment along the circumferential direction, and the multiple pairs of connected and non-connected third wave crests and third wave troughs are sequentially spaced in the circumferential direction of the third bracket unit ring; and / or,

[0030] Adjacent fourth bracket unit rings have multiple pairs of fourth wave crests and fourth wave valleys that match each other in the axial direction of the second spaced bracket segment along the circumferential direction, and the multiple pairs of connected and unconnected fourth wave crests and fourth wave valleys are sequentially spaced in the circumferential direction of the fourth bracket unit ring; and / or,

[0031] Adjacent fifth bracket unit rings have multiple pairs of fifth wave peaks that cooperate with each other in the axial direction of the middle bracket segment along the circumferential direction, the logarithm of the non-connected fifth wave peaks is an integer multiple of the logarithm of the connected fifth wave peaks, and the connected fifth wave peaks in different adjacent fifth bracket units are staggered in the circumferential direction of the middle bracket segment.

[0032] In one embodiment, part of the first wave valley of the first bracket unit ring located at the end of the first end bracket segment is connected to part of the third wave peak of the third bracket unit ring located at the end of the first spaced bracket segment; and / or,

[0033] The second wave crest of the second bracket unit ring located at the end of the second end bracket segment is connected to the fourth wave trough of the fourth bracket unit ring located at the end of the second spaced bracket segment; and / or,

[0034] A portion of the third wave valley of the third bracket unit ring located at the end of the first spaced bracket segment is connected to a portion of the fifth wave peak of the fifth bracket unit ring located at the end of the middle bracket segment, and the portion of the fifth wave peak is not simultaneously connected to the portion of the third wave valley and the fifth wave peak of other fifth bracket unit rings in the middle bracket segment; and / or,

[0035] A portion of the fourth wave peak of the fourth bracket unit ring located at the end of the second interval bracket segment is connected to a portion of the fifth wave trough of the fifth bracket unit ring located at the end of the middle bracket segment, and the portion of the fifth wave trough is not simultaneously connected to the portion of the fourth wave peak and the fifth wave trough of other fifth bracket unit rings in the middle bracket segment.

[0036] In one embodiment, the peak width of the fifth peak is greater than the stent width of the fifth stent unit ring.

[0037] In one embodiment, the peak width of the fifth peak is 1.1 to 3 times the stent width of the fifth stent unit ring.

[0038] The present application provides a medical stent, which comprises the stent structure, at least a portion of the surface of the stent structure is provided with a polymer layer, and at least a portion of the surface of the polymer layer is provided with a drug coating.

[0039] In the above-mentioned stent structure and medical stent, the stent structure is divided into five sections, and the flexibility of each section can be designed in a targeted manner. The flexibility design of the first end stent segment and the second end stent segment can ensure that the first end stent segment and the second end stent segment have sufficient supporting force, and can achieve firm anchoring. The flexibility design of the first interval stent segment and the second interval stent segment can ensure that the first interval stent segment and the second interval stent segment have a certain stent flexibility, while improving the conduction of axial force during the release of the stent structure, providing positioning accuracy, and reducing the poor stent release morphology caused by inaccurate positioning and shortening of the stent structure, ensuring that the stent structure can completely cover the lesion, and improving the fatigue resistance and long-term patency of the stent structure. The flexibility design of the middle stent segment can ensure that the middle stent segment has very good flexibility, and then conform to various complex stress conditions such as peripheral blood vessel bending, torsion, compression, and extrusion, reducing the risk of vascular damage and stent fracture caused by poor compliance of the stent structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a schematic diagram of a support structure provided in one embodiment of the present application.

[0041] Figure 2 This is a partial schematic diagram of a support structure provided in one embodiment of the present application.

[0042] Figure 3 It is a schematic diagram comparing the peak width and the support width of the support structure in the prior art.

[0043] Figure 4 This is a schematic diagram comparing the peak width and the support width of the support structure in one embodiment of the present application.

[0044] Figure 5 This is a cross-sectional schematic diagram of a support structure provided in one embodiment of the present application.

[0045] Figure 6 It is a three-dimensional schematic diagram of the support structure provided in one embodiment of the present application.

[0046] Figure Number:

[0047] 100, stent structure; 200, polymer layer; 300, drug coating;

[0048] 1000, first end bracket segment; 2000, second end bracket segment; 3000, first interval bracket segment; 4000, second interval bracket segment; 5000, middle bracket segment; 6000, developing element;

[0049] 1100, first bracket unit ring; 1100a, first wave crest; 1100b, first wave valley; 1200, first connecting element;

[0050] 2100, second bracket unit ring; 2100a, second wave crest; 2100b, second wave valley; 2200, second connecting element;

[0051] 3100, third bracket unit ring; 3100a, third wave crest; 3100b, third wave valley; 3200, third connecting element;

[0052] 4100, fourth bracket unit ring; 4100a, fourth wave crest; 4100b, fourth wave valley; 4200, fourth connecting element;

[0053] 5100, fifth bracket unit ring; 5100a, fifth wave crest; 5100b, fifth wave valley; 5200, fifth connecting element;

[0054] 5000a, wave peak width; 5000b, bracket width; 5000c, stress concentration position. DETAILED DESCRIPTION

[0055] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0056] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0057] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0058] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0059] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0060] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method. Among them, each peak in the support structure represents such as Figure 1 The tip of the wave is pointed upward, and each trough represents Figure 1 The pointed part facing downward.

[0061] like Figure 1 and Figure 2 As shown, an embodiment of the present application provides a support structure 100, which includes a first end support segment 1000, a second end support segment 2000, a first interval support segment 3000, a second interval support segment 4000 and a middle support segment 5000, a total of five segments. Figure 1 As shown, the first interval bracket segment 3000 and the second interval bracket segment 4000 are respectively connected to the two ends of the middle bracket segment 5000, the first end bracket segment 1000 is connected to the end of the first interval bracket segment 3000, and the second end bracket segment 2000 is connected to the end of the second interval bracket segment 4000.

[0062] The support structure 100 provided in the present application defines that at least one of the first end support segment 1000 and the second end support segment 2000 has a first frame flexibility, at least one of the first interval support segment 3000 and the second interval support segment 4000 has a second frame flexibility, and the middle support segment 5000 has a third frame flexibility. The first frame flexibility is less than the second frame flexibility, and the second frame flexibility is less than the third frame flexibility.

[0063] For example, the flexibility of the first end bracket segment 1000 and the second end bracket segment 2000 is consistent, so that the flexibility of the first end bracket segment 1000 and the second end bracket segment 2000 is the first frame flexibility, and the flexibility of the first interval bracket segment 3000 and the second interval bracket segment 4000 is consistent, so that the flexibility of the first interval bracket segment 3000 and the second interval bracket segment 4000 is the second frame flexibility. Therefore, the first end bracket segment 1000 and the second end bracket segment 2000 located at both ends of the bracket structure 100 will be the two sections with the lowest flexibility in the entire bracket structure 100, that is, the two sections with the highest hardness. The middle bracket segment 5000 located in the center of the bracket structure 100 will be the section with the highest flexibility in the entire bracket structure 100. The first interval bracket segment 3000 and the second interval bracket segment 4000 between the middle bracket segment 5000 and the first end bracket segment 1000 and the second end bracket segment 2000 will be two sections with relatively moderate flexibility in the entire bracket structure 100, and the flexibility of these two sections has a transitional effect.

[0064] The flexibility design of the first end stent segment 1000 and the second end stent segment 2000 can ensure that the first end stent segment 1000 and the second end stent segment 2000 have sufficient support force and can achieve firm anchoring. The flexibility design of the first interval stent segment 3000 and the second interval stent segment 4000 can ensure that the first interval stent segment 3000 and the second interval stent segment 4000 have a certain stent flexibility, while improving the conduction of axial force during the release process of the stent structure 100, providing positioning accuracy, reducing the poor stent release form caused by inaccurate positioning and shortening of the stent structure 100, ensuring that the stent structure 100 can completely cover the lesion, and improving the fatigue resistance and long-term patency of the stent structure 100. The flexibility design of the middle stent segment 5000 can ensure that the middle stent segment 5000 has very good flexibility, and then conform to various composite stress conditions such as peripheral blood vessel bending, torsion, compression, and extrusion, reducing the risk of vascular damage and stent fracture caused by poor compliance of the stent structure 100.

[0065] Moreover, the first end stent segment 1000 and the second end stent segment 2000 are of closed-loop design, which can make the stent structure more rounded, and avoid the first end stent segment 1000 and the second end stent segment 2000 of the stent structure from poorly adhering to the blood vessel wall, and the generation of eddy currents when blood flows through, causing restenosis. At the same time, the closed-loop design of the stent structure can also prevent the top of the stent structure from tilting, stimulating the healthy anchoring area blood vessels, and reducing the in-stent restenosis caused by cell proliferation.

[0066] Those skilled in the art can adjust the specific flexibility values ​​and relative flexibility differences of the first end bracket segment 1000, the second end bracket segment 2000, the first interval bracket segment 3000, the second interval bracket segment 4000 and the middle bracket segment 5000 according to actual needs. Moreover, those skilled in the art can adjust the flexibility of the first end bracket segment 1000, the second end bracket segment 2000, the first interval bracket segment 3000, the second interval bracket segment 4000 and the middle bracket segment 5000 through material design or structural design, etc., which is not limited here.

[0067] For example, when the flexibility is adjusted based on the structural design, in one embodiment, the first end bracket segment 1000 may include a plurality of first bracket unit rings 1100, and the first bracket unit rings 1100 have a plurality of first wave crests 1100a and first wave troughs 1100b that are sequentially spaced in the circumferential direction. Figure 1 As shown, the first wave crest 1100a is the first wave crest of the first bracket unit ring 1100. Figure 1 The first wave valley 1100b is the tip portion of the first bracket unit ring 1100. Figure 1 The tip portion at the lower middle part. A plurality of first bracket unit rings 1100 are arranged along the axial direction of the first end bracket segment 1000, and the first wave crests 1100a and the first wave valleys 1100b of adjacent first bracket unit rings 1100 are connected. For example, adjacent first wave crests 1100a and first wave valleys 1100b are connected by a first connecting element 1200. The first connecting element 1200 can be at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod, or an Ω-shaped rod.

[0068] Moreover, the straight line between the connected first wave crests 1100a and the first wave valleys 1100b may be parallel to the axis of the first end bracket segment 1000, or the straight line between the connected first wave crests 1100a and the first wave valleys 1100b may have an angle with the axis of the first end bracket segment 1000. When the straight line between the connected first wave crests 1100a and the first wave valleys 1100b and the axis of the first end bracket segment 1000 have an angle, the connected first wave crests 1100a and the first wave valleys 1100b may have a first offset distance in the circumferential direction of the first end bracket segment 1000, and the setting of the first offset distance may increase the flexibility of the bracket structure to a certain extent, for example, especially when the bracket structure is bent. At this time, the first offset distance may be defined as being smaller than the straight line distance between the connected first wave crests 1100a and the first wave valleys 1100b.

[0069] Since all the first wave crests 1100a and the first wave valleys 1100b are connected, the first end stent segment 1000 can form a fully closed loop structure, that is, in the circumferential direction of the first end stent segment 1000, the number of the first connecting elements 1200 is equal to the number of the first wave crests 1100a or the first wave valleys 1100b. Among them, the number of the first wave crests 1100a or the first wave valleys 1100b can be 4 to 40, and the number of the first stent unit rings 1100 can be 2, 3 or other numbers. The fully closed loop structure can make the structure of the first end stent segment 1000 more rounded, avoid the poor adhesion of the first end stent segment 1000 to the blood vessel wall, avoid the problem of eddy currents and restenosis when blood flows through. At the same time, the fully closed loop structure can also avoid the first wave crest 1100a or the first wave valley 1100b from tilting, avoid stimulation of the healthy anchoring area blood vessels, and reduce the restenosis in the stent caused by cell proliferation. In addition, the number of the first bracket unit ring 1100 may also be one, and in this case, the first wave peak 1100a and the first wave valley 1100b connected to each other may not be formed at the end.

[0070] Similar to the first end bracket segment 1000, the second end bracket segment 2000 may include a plurality of second bracket unit rings 2100, and the second bracket unit rings 2100 have a plurality of second wave crests 2100a and second wave valleys 2100b which are sequentially spaced in the circumferential direction. Figure 1 As shown, the second wave peak 2100a is the second wave peak in the second bracket unit ring 2100. Figure 1 The second wave valley 2100b is the tip portion of the second bracket unit ring 2100. Figure 1The tip portion at the lower middle part. A plurality of second bracket unit rings 2100 are arranged along the axial direction of the second end bracket segment 2000, and the second wave crests 2100a and second wave valleys 2100b of adjacent second bracket unit rings 2100 are connected. For example, adjacent second wave crests 2100a and second wave valleys 2100b are connected by a second connecting element 2200. The second connecting element 2200 can be at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod, or an Ω-shaped rod.

[0071] Moreover, the straight line between the connected second wave crest 2100a and the second wave valley 2100b may be parallel to the axis of the second end bracket segment 2000, or the straight line between the connected second wave crest 2100a and the second wave valley 2100b may have an angle with the axis of the second end bracket segment 2000. When the straight line between the connected second wave crest 2100a and the second wave valley 2100b has an angle with the axis of the second end bracket segment 2000, the connected second wave crest 2100a and the second wave valley 2100b may have a second offset distance in the circumferential direction of the second end bracket segment 2000. In this case, the second offset distance may be defined as being smaller than the straight-line distance between the connected second wave crest 2100a and the second wave valley 2100b.

[0072] Since all the second wave crests 2100a and the second wave valleys 2100b are connected, the second end stent segment 2000 can form a fully closed loop structure, that is, in the circumferential direction of the second end stent segment 2000, the number of the second connecting elements 2200 is equal to the number of the second wave crests 2100a or the second wave valleys 2100b. Among them, the number of the second wave crests 2100a or the second wave valleys 2100b can be 4 to 40, and the number of the second stent unit rings 2100 can be 1 to 3. The fully closed loop structure can make the structure of the second end stent segment 2000 more rounded, avoid the poor adhesion of the second end stent segment 2000 to the blood vessel wall, avoid the problem of eddy currents and restenosis when blood flows through. At the same time, the fully closed loop structure can also avoid the second wave crest 2100a or the second wave valley 2100b from tilting, avoid stimulation of the healthy anchoring area blood vessels, and reduce the restenosis in the stent caused by cell proliferation.

[0073] The first spacing bracket segment 3000 may include a plurality of third bracket unit rings 3100, and the third bracket unit rings 3100 have a plurality of third wave crests 3100a and third wave valleys 3100b which are sequentially spaced in the circumferential direction. Figure 1 As shown, the third wave peak 3100a is the third wave peak 3100 in the third bracket unit ring 3100. Figure 1 The third wave valley 3100b is the tip portion of the third bracket unit ring 3100. Figure 1The tip portion at the lower middle part. A plurality of third bracket unit rings 3100 are arranged along the axial direction of the first spaced bracket segment 3000, and parts of the third wave crests 3100a and third wave valleys 3100b in adjacent third bracket unit rings 3100 are connected. Adjacent third wave crests 3100a and third wave valleys 3100b can be connected by a third connecting element 3200, and the third connecting element 3200 can be at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod, or an Ω-shaped rod.

[0074] In one embodiment, the adjacent third bracket unit ring 3100 has multiple pairs of third wave peaks 3100a and third wave valleys 3100b that cooperate with each other in the axial direction of the first interval bracket segment 3000 along the circumferential direction. Among the multiple pairs of third wave peaks 3100a and third wave valleys 3100b that cooperate with each other in the axial direction, multiple pairs of connected and unconnected third wave peaks 3100a and third wave valleys 3100b are sequentially arranged in the circumferential direction of the third bracket unit ring 3100, that is, the connected third wave peaks 3100a and third wave valleys 3100b and the unconnected third wave peaks 3100a and third wave valleys 3100b are sequentially arranged along the circumferential direction. At this time, among the multiple pairs of third wave peaks 3100a and third wave valleys 3100b, the number of connected and unconnected ones is the same. In addition, those skilled in the art can also adjust the relative number of connected and unconnected ones among the multiple pairs of third wave peaks 3100a and third wave valleys 3100b according to actual needs, which is not limited here.

[0075] Moreover, the straight line between the connected third wave crests 3100a and the third wave valleys 3100b may be parallel to the axis of the first spaced support segment 3000, or the straight line between the connected third wave crests 3100a and the third wave valleys 3100b may have an angle with the axis of the first spaced support segment 3000. When the straight line between the connected third wave crests 3100a and the third wave valleys 3100b has an angle with the axis of the first spaced support segment 3000, the connected third wave crests 3100a and the third wave valleys 3100b may have a third offset distance in the circumferential direction of the first spaced support segment 3000. In this case, the third offset distance may be defined to be smaller than the straight-line distance between the connected third wave crests 3100a and the third wave valleys 3100b.

[0076] Different from the structural design of the first end bracket segment 1000 and the second end bracket segment 2000, at this time, only part of the third wave crests 3100a and the third wave valleys 3100b are connected in the adjacent third bracket unit rings 3100, that is, there are third wave crests 3100a and third wave valleys 3100b that are not connected. Therefore, the structure formed by the first interval bracket segment 3000 can be called a semi-closed loop structure, that is, in the circumferential direction of the first interval bracket segment 3000, the number of the third connecting elements 3200 is less than the number of the third wave crests 3100a or the third wave valleys 3100b. Thus, by reducing the number of the third wave crests 3100a and the third wave valleys 3100b connected, the flexibility of the first interval bracket segment 3000 is reduced. Among them, the number of the third wave crests 3100a or the third wave valleys 3100b can be 4 to 40, and the number of the third bracket unit rings 3100 can be 2, 3 or other numbers. In addition, the number of the third bracket unit ring 3100 may also be one, and in this case, the third wave peak 3100a and the third wave valley 3100b connected to each other may not be formed.

[0077] The second spacing bracket segment 4000 may include a plurality of fourth bracket unit rings 4100, and the fourth bracket unit rings 4100 have a plurality of fourth wave crests 4100a and fourth wave valleys 4100b which are sequentially spaced in the circumferential direction. Figure 1 As shown, the fourth wave peak 4100a is the fourth wave peak in the fourth bracket unit ring 4100. Figure 1 The fourth wave valley 4100b is the tip portion of the fourth support unit ring 4100. Figure 1 The tip portion at the lower middle part. A plurality of fourth bracket unit rings 4100 are arranged along the axial direction of the second spaced bracket segment 4000, and portions of fourth wave crests 4100a and fourth wave valleys 4100b in adjacent fourth bracket unit rings 4100 are connected. For example, adjacent fourth wave crests 4100a and fourth wave valleys 4100b are connected by a fourth connecting element 4200, and the fourth connecting element 4200 can be at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod, or an Ω-shaped rod.

[0078] In one embodiment, the adjacent fourth support unit ring 4100 has a plurality of pairs of fourth wave crests 4100a and fourth wave valleys 4100b that cooperate with each other in the axial direction of the second spaced support segment 4000 along the circumferential direction. Among the plurality of pairs of fourth wave crests 4100a and fourth wave valleys 4100b that cooperate with each other in the axial direction, the plurality of connected and non-connected pairs of fourth wave crests 4100a and fourth wave valleys 4100b are sequentially arranged in the circumferential direction of the fourth support unit ring 4100, that is, the connected fourth wave crests 4100a and fourth wave valleys 4100b and the non-connected fourth wave crests 4100a and fourth wave valleys 4100b are sequentially arranged in the circumferential direction. At this time, among the plurality of pairs of fourth wave crests 4100a and fourth wave valleys 4100b, the number of connected and non-connected pairs is the same. In addition, those skilled in the art can also adjust the relative number of connected and non-connected pairs of fourth wave crests 4100a and fourth wave valleys 4100b according to actual needs, which is not limited here.

[0079] Moreover, the straight line between the connected fourth wave crest 4100a and the fourth wave valley 4100b may be parallel to the axis of the second spaced support segment 4000, or the straight line between the connected fourth wave crest 4100a and the fourth wave valley 4100b may have an angle with the axis of the second spaced support segment 4000. When the straight line between the connected fourth wave crest 4100a and the fourth wave valley 4100b has an angle with the axis of the first spaced support segment 3000, the connected fourth wave crest 4100a and the fourth wave valley 4100b may have a fourth offset distance in the circumferential direction of the first spaced support segment 3000. In this case, the fourth offset distance may be defined to be smaller than the straight-line distance between the connected fourth wave crest 4100a and the fourth wave valley 4100b.

[0080] Different from the structural design of the first end bracket segment 1000 and the second end bracket segment 2000, at this time, only part of the fourth wave crests 4100a and the fourth wave valleys 4100b are connected in the adjacent fourth bracket unit rings 4100, that is, there are fourth wave crests 4100a and fourth wave valleys 4100b that are not connected. Therefore, the structure formed by the second interval bracket segment 4000 can be called a semi-closed loop structure, that is, in the circumferential direction of the second interval bracket segment 4000, the number of the fourth connecting elements 4200 is less than the number of the fourth wave crests 4100a or the fourth wave valleys 4100b. Thus, by reducing the number of fourth wave crests 4100a and fourth wave valleys 4100b connected, the flexibility of the second interval bracket segment 4000 is reduced. Among them, the number of fourth wave crests 4100a or fourth wave valleys 4100b can be 4 to 40, and the number of fourth bracket unit rings 4100 can be 1 to 3.

[0081] The middle stent segment 5000 may include a plurality of fifth stent unit rings 5100, and the fifth stent unit rings 5100 have a plurality of fifth wave crests 5100a and fifth wave valleys 5100b which are sequentially spaced in the circumferential direction. Figure 1 As shown, the fifth wave peak 5100a is the fifth wave peak in the fifth bracket unit ring 5100. Figure 1 The fifth wave valley 5100b is the tip portion of the fifth bracket unit ring 5100. Figure 1 The tip portion at the lower middle part. A plurality of fifth support unit rings 5100 are arranged along the axial direction of the middle support segment 5000, and parts of the fifth wave crests 5100a in adjacent fifth support unit rings 5100 are connected. For example, parts of the fifth wave crests 5100a in adjacent fifth support unit rings 5100 are connected by a fifth connecting element 5200. The fifth connecting element 5200 can be at least one of a straight rod body, an S-shaped rod body, a V-shaped rod body, an N-shaped rod body or an Ω-shaped rod body. Moreover, the straight line between the connected fifth wave crests 5100a can be parallel to the axis of the middle support segment 5000, or the straight line between the connected fifth wave crests 5100a has an angle with the axis of the middle support segment 5000.

[0082] Compared with the structural design of the first spaced support segment 3000 and the second spaced support segment 4000, at this time, the number of the fifth wave crests 5100a connected in the adjacent fifth support unit rings 5100 is further reduced, and the connection is at the crest position, not the crest position and the trough position. Therefore, the structure formed by the middle support segment 5000 can be called an open ring structure. Thus, by further reducing the number of connections between the fifth wave crests 5100a, the flexibility of the middle support segment 5000 is reduced.

[0083] The number of the fifth wave crests 5100a may be 4 to 40, and the number of the fifth support unit rings 5100 may be 4 to 150. A larger number makes the middle support segment 5000 the main section of the support structure 100. In one embodiment, by designing the positions, number and other factors of the fifth wave crests 5100a connected in the adjacent fifth support unit rings 5100, the middle support segment 5000 may be constructed into a frame structure similar to a spiral form as a whole. For example, all the fifth wave crests 5100a connected are relatively dislocated in the circumferential direction, and the dislocation of the fifth wave crests 5100a connected is gradually dislocated in a rotation direction in the axial direction. For example, Figure 1 shown.

[0084] In one embodiment, adjacent fifth stent unit rings 5100 have multiple pairs of fifth wave crests 5100a that cooperate with each other in the axial direction of the middle stent segment 5000 along the circumferential direction, and the number of pairs of non-connected fifth wave crests 5100a is an integer multiple of the number of pairs of connected fifth wave crests 5100a, for example, the multiple between the two can be 3 times or more, thereby further reducing the number of connections between the fifth wave crests 5100a and improving the flexibility of the middle stent segment 5000. In addition, referring to Figure 2 As shown, the fifth wave peaks 5100a connected in different adjacent fifth stent units are staggered in the circumferential direction of the middle stent segment 5000. For example, when connected by the fifth connecting element 5200, the fifth connecting elements 5200 of adjacent fifth stent unit rings 5100 may not all correspond to each other in the axial direction, or may not all correspond to each other in the axial direction. As a result, the above-mentioned spiral-shaped frame structure can be constructed in the middle stent segment 5000, which reduces stress concentration, reduces the risk of fracture of the stent structure 100, ensures the uniformity and structural stability of the stent structure 100 in the axial direction, ensures the uniformity of the release form of the stent structure 100, and improves fatigue resistance and long-term patency.

[0085] When constructing a spiral frame structure, the fifth connecting elements 5200 between adjacent fifth stent unit rings 5100 may not correspond to each other in the axial direction only between two axially adjacent fifth stent unit rings 5100, but correspond to each other in the axial direction between the fifth stent unit rings 5100 that are spaced apart, as shown in FIG. Figure 2 Alternatively, the fifth connection elements 5200 between adjacent fifth stent unit rings 5100 may not correspond to any other fifth connection elements 5200 in the axial direction, or may only correspond to some other fifth connection elements 5200, which is not limited here.

[0086] Continue reading Figure 3 and Figure 4 As shown, in Figure 3 In the structural design shown, the peak width 5000a of the fifth peak 5100a is the same as the stent width 5000b of the fifth stent unit ring 5100, that is, L1 is equal to L2. Finite element analysis of this stent structure 100 shows that the stress concentration position 5000c of the entire stent structure 100 when subjected to force in a blood vessel is on the inner side of the fifth peak 5100a. Finite element analysis shows that the fatigue safety factor of the stent structure 100 is 5.62.

[0087] When Figure 4As shown, when the peak width 5000a of the fifth peak 5100a is greater than the stent width 5000b of the fifth stent unit ring 5100, that is, L3 is greater than L4. In one embodiment, the peak width 5000a of the fifth peak 5100a can be limited to 1.1 to 3 times the stent width 5000b of the fifth stent unit ring 5100. It can also be seen from the finite element analysis that the stress concentration position 5000c of the stent structure 100 when it is subjected to force in the blood vessel is dispersed to both sides of the fifth peak 5100a, which can significantly reduce stress concentration and improve the overall fatigue resistance of the stent structure 100. It can be concluded from the finite element analysis that the improved stent structure 100 increases the fatigue safety factor of the stent structure 100 from 5.62 to 6.94, and the fatigue resistance is improved by about 23.5%.

[0088] The support structure 100 can be a laser engraved support. The metal tube is engraved into the designed support structure 100 by laser engraving technology, and then shaped into the required support size by heat treatment. The metal tube is a shape memory polymer material or metal material with high resilience, such as nickel-titanium alloy, and elastic metal materials such as cobalt-chromium alloy and stainless steel. The developing element 6000 can be set on the support structure 100, for example, the developing element 6000 is set at the two ends of the support structure 100, that is, located on at least one of the first end support segment 1000 and the second end support segment 2000. The developing element 6000 can be fixed to the support structure 100 by interference fit or laser welding. The developing element 6000 can be made of X-ray non-transmissive materials, such as tantalum, gold, platinum-tungsten alloy, platinum-iridium alloy, etc.

[0089] The first end bracket segment 1000 is connected to the end of the first interval bracket segment 3000, that is, a part of the first wave valley 1100b of the first bracket unit ring 1100 located at the end of the first end bracket segment 1000 is connected to a part of the third wave peak 3100a of the third bracket unit ring 3100 located at the end of the first interval bracket segment 3000. The second end bracket segment 2000 is connected to the end of the second interval bracket segment 4000, that is, a part of the second wave peak 2100a of the second bracket unit ring 2100 located at the end of the second end bracket segment 2000 is connected to a part of the fourth wave valley 4100b of the fourth bracket unit ring 4100 located at the end of the second interval bracket segment 4000.

[0090] The first spaced support segment 3000 and the second spaced support segment 4000 are connected to both ends of the middle support segment 5000, respectively, that is, part of the third wave valley 3100b of the third support unit ring 3100 located at the end of the first spaced support segment 3000 is connected to part of the fifth wave peak 5100a of the fifth support unit ring 5100 located at the end of the middle support segment 5000, and part of the fourth wave peak 4100a of the fourth support unit ring 4100 located at the end of the second spaced support segment 4000 is connected to part of the fifth wave valley 5100b of the fifth support unit ring 5100 located at the end of the middle support segment 5000. Moreover, it can be defined that the above-mentioned part of the fifth wave peak 5100a is not connected to the third wave valley 3100b and the fifth wave peak 5100a of the other fifth support unit ring in the middle support segment at the same time, and at the same time, the above-mentioned part of the fifth wave valley 5100b is not connected to the fourth wave peak 4100a and the fifth wave valley 5100b of the other fifth support unit ring in the middle support segment at the same time. It can also reduce the stress concentration of the stent structure 100 when it is subjected to stress, ensure that the stent structure 100 is subjected to stress evenly, and improve the fatigue resistance and long-term patency rate of the stent structure 100.

[0091] The present application provides a medical stent, which includes a stent structure 100, a polymer layer 200 is disposed on at least a portion of the surface of the stent structure 100, and a drug coating 300 is disposed on at least a portion of the surface of the polymer layer 200. The polymer layer 200 and the drug coating 300 can be sprayed on one side, multiple sides, or completely wrap the stent structure 100.

[0092] The preparation method of the medical stent may include the following steps: dissolving a first polymer in a first organic solvent to obtain a first solution, and placing the first solution on the surface of the stent structure 100 to form a polymer layer 200. Dissolving a second polymer and a pharmaceutical active ingredient in a second organic solvent to obtain a second solution, and placing the second solution on the surface of the polymer layer 200 to form a drug coating 300.

[0093] For example, after the first polymer is dissolved in the first organic solvent to obtain a clear, transparent, uniform first solution, the first solution can be loaded into the syringe of the drug sprayer, and the surface of the stent structure 100 is sprayed with the bottom layer to obtain the polymer layer 200. After the second polymer and the active pharmaceutical ingredient are dissolved in the second organic solvent to obtain a clear, transparent, uniform second solution, the second solution can be loaded into the syringe of the drug sprayer, and the surface of the polymer layer 200 is sprayed with the top layer to obtain the drug coating 300.

[0094] The polymer layer 200 is used as an intermediate layer to bond the stent structure 100 and the drug coating 300, which can improve the firmness of the drug coating 300, reduce the drug loss during the installation and transportation of the stent structure 100, and avoid the drug coating 300 from falling off and causing distal embolism. The drug coating 300 is coated on the surface of the stent structure 100, which can inhibit the proliferation and migration of smooth muscle cells, reduce restenosis in the blood vessel, and improve the late patency rate of the blood vessel. Therefore, by using the polymer layer 200 and the drug coating 300 together, the drug release rate can be reduced while reducing the amount of drug used, thereby ensuring the safety of the organism.

[0095] The first polymer includes at least one of polymethyl methacrylate, polyethyl methacrylate, polybutyl methacrylate, polybutyl acrylate and polyethyl acrylate. The first organic solvent or the second organic solvent includes at least one of methanol, ethanol, acetone, butanone, tetrahydrofuran and cyclohexanone. The second polymer includes at least one of polyvinylidene fluoride-hexafluoropropylene copolymer, polytetrafluoroethylene, fluorinated polyethylene-propylene copolymer, polyhexafluoropropylene, polytetrafluoroethylene-hexafluoropropylene copolymer, polyhexafluoropropylene-ethylene-ethylene copolymer, polyhexafluoroethylene-tetrafluoroethylene copolymer and polyvinylidene fluoride-trifluoroethylene copolymer. The active pharmaceutical ingredient includes at least one of antiproliferative drugs, anticoagulants and anti-inflammatory drugs, for example, paclitaxel, sirolimus and derivatives thereof, heparin and analogs thereof, actinomycin, mitomycin, argatroban, dextran, hirudin, colchicine, etc.

[0096] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0097] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A support structure, characterized in that: The support structure comprises: middle bracket segment; a first spaced support segment and a second spaced support segment, wherein the first spaced support segment and the second spaced support segment are respectively connected to two ends of the middle support segment; A first end bracket segment and a second end bracket segment, wherein the first end bracket segment is connected to an end of the first interval bracket segment, and the second end bracket segment is connected to an end of the second interval bracket segment; At least one of the first end bracket segment and the second end bracket segment has a first frame flexibility, at least one of the first interval bracket segment and the second interval bracket segment has a second frame flexibility, and the middle bracket segment has a third frame flexibility, the first frame flexibility is less than the second frame flexibility, and the second frame flexibility is less than the third frame flexibility.

2. The support structure according to claim 1, characterized in that: The first end bracket segment comprises a plurality of first bracket unit rings, the first bracket unit rings have a plurality of first wave crests and first wave troughs arranged in sequence in the circumferential direction, the plurality of first bracket unit rings are arranged along the axial direction of the first end bracket segment, and the first wave crests and the first wave troughs which are closest in axial distance among adjacent first bracket unit rings are connected; and / or, The second end bracket segment comprises a plurality of second bracket unit rings, the second bracket unit rings have a plurality of second wave crests and second wave troughs arranged in sequence in the circumferential direction, the plurality of second bracket unit rings are arranged along the axial direction of the second end bracket segment, and the second wave crests and the second wave troughs in adjacent second bracket unit rings that are closest in axial direction are connected; and / or, The first spaced support segment comprises a plurality of third support unit rings, the third support unit rings have a plurality of third wave crests and third wave troughs arranged in sequence in the circumferential direction, the plurality of third support unit rings are arranged along the axial direction of the first spaced support segment, and the third wave crests and the third wave troughs of the parts of adjacent third support unit rings that are closest in axial direction are connected; and / or, The second spaced support segment comprises a plurality of fourth support unit rings, the fourth support unit rings having a plurality of fourth wave crests and fourth wave troughs spaced in sequence in the circumferential direction, the plurality of fourth support unit rings being arranged along the axial direction of the second spaced support segment, and the fourth wave crests and the fourth wave troughs of the parts of adjacent fourth support unit rings that are closest in axial direction are connected; and / or, The middle support segment includes a plurality of fifth support unit rings, each of which has a plurality of fifth wave crests and fifth wave troughs arranged in sequence in the circumferential direction. The plurality of fifth support unit rings are arranged along the axial direction of the middle support segment, and the fifth wave crests of the adjacent fifth support unit rings that are closest in axial distance are connected.

3. The support structure according to claim 2, characterized in that: The adjacent first wave crests and the first wave troughs are connected by a first connecting element; wherein a straight line between the connected first wave crests and the first wave troughs is parallel to the axis of the first end bracket segment, or a straight line between the connected first wave crests and the first wave troughs has an angle with the axis of the first end bracket segment; and / or, Adjacent second wave crests and second wave troughs are connected by a second connecting element; wherein a straight line between the connected second wave crests and second wave troughs is parallel to the axis of the second end bracket segment, or a straight line between the connected second wave crests and second wave troughs has an angle with the axis of the second end bracket segment; and / or, The adjacent third wave crests and the third wave troughs are connected via a third connecting element; wherein a straight line between the connected third wave crests and the third wave troughs is parallel to the axis of the first spaced support segment, or a straight line between the connected third wave crests and the third wave troughs has an angle with the axis of the first spaced support segment; and / or, The adjacent fourth wave crests and the fourth wave troughs are connected via a fourth connecting element; wherein a straight line between the connected fourth wave crests and the fourth wave troughs is parallel to the axis of the second spaced support segment, or a straight line between the connected fourth wave crests and the fourth wave troughs forms an angle with the axis of the second spaced support segment; and / or, Part of the fifth wave peaks in adjacent fifth bracket unit rings are connected by a fifth connecting element; wherein, a straight line between the connected fifth wave peaks is parallel to the axis of the middle bracket segment, or a straight line between the connected fifth wave peaks has an angle with the axis of the middle bracket segment.

4. The support structure according to claim 3, characterized in that: A straight line between the first wave crests and the first wave troughs connected to each other has an angle with the axis of the first end bracket segment, so that the first wave crests and the first wave troughs connected to each other have a first offset distance in the circumferential direction of the first end bracket segment, and the first offset distance is smaller than a straight-line distance between the first wave crests and the first wave troughs connected to each other; and / or, A straight line between the connected second wave crests and the second wave troughs has an included angle with the axis of the second end bracket segment, so that the connected second wave crests and the second wave troughs have a second offset distance in the circumferential direction of the second end bracket segment, and the second offset distance is smaller than a straight-line distance between the connected second wave crests and the second wave troughs; and / or, A straight line between the connected third wave crests and the third wave troughs has an included angle with the axis of the first spaced support segment, so that the connected third wave crests and the third wave troughs have a third offset distance in the circumferential direction of the first spaced support segment, and the third offset distance is smaller than a straight-line distance between the connected third wave crests and the third wave troughs; and / or, A straight line between the connected fourth wave peaks and the fourth wave valleys has an angle with the axis of the second interval bracket segment, so that the connected fourth wave peaks and the fourth wave valleys have a fourth offset distance in the circumferential direction of the second interval bracket segment, and the fourth offset distance is smaller than the straight-line distance between the connected fourth wave peaks and the fourth wave valleys.

5. The support structure according to claim 3, characterized in that: The first connecting element is at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod or an Ω-shaped rod; And / or, the second connecting element is at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod or an Ω-shaped rod; And / or, the third connecting element is at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod or an Ω-shaped rod; And / or, the fourth connecting element is at least one of a straight rod, an S-shaped rod, a V-shaped rod, an N-shaped rod or an Ω-shaped rod; And / or, the fifth connecting element is at least one of a linear rod, an S-shaped rod, a V-shaped rod, an N-shaped rod or an Ω-shaped rod.

6. The support structure according to claim 2, characterized in that: Adjacent third bracket unit rings have multiple pairs of third wave crests and third wave troughs that match each other in the axial direction of the first spaced bracket segment along the circumferential direction, and the multiple pairs of connected and unconnected third wave crests and third wave troughs are sequentially spaced in the circumferential direction of the third bracket unit ring; and / or, Adjacent fourth bracket unit rings have multiple pairs of fourth wave crests and fourth wave valleys that match each other in the axial direction of the second spaced bracket segment along the circumferential direction, and the multiple pairs of connected and unconnected fourth wave crests and fourth wave valleys are sequentially spaced in the circumferential direction of the fourth bracket unit ring; and / or, Adjacent fifth bracket unit rings have multiple pairs of fifth wave peaks that cooperate with each other in the axial direction of the middle bracket segment along the circumferential direction, the logarithm of the non-connected fifth wave peaks is an integer multiple of the logarithm of the connected fifth wave peaks, and the connected fifth wave peaks in different adjacent fifth bracket units are staggered in the circumferential direction of the middle bracket segment.

7. The support structure according to claim 2, characterized in that: Part of the first wave valley of the first bracket unit ring located at the end of the first end bracket segment is connected to part of the third wave peak of the third bracket unit ring located at the end of the first spaced bracket segment; and / or, The second wave crest of the second bracket unit ring located at the end of the second end bracket segment is connected to the fourth wave trough of the fourth bracket unit ring located at the end of the second spaced bracket segment; and / or, A portion of the third wave valley of the third bracket unit ring located at the end of the first spaced bracket segment is connected to a portion of the fifth wave peak of the fifth bracket unit ring located at the end of the middle bracket segment, and the portion of the fifth wave peak is not simultaneously connected to the portion of the third wave valley and the fifth wave peak of other fifth bracket unit rings in the middle bracket segment; and / or, A portion of the fourth wave peak of the fourth bracket unit ring located at the end of the second interval bracket segment is connected to a portion of the fifth wave trough of the fifth bracket unit ring located at the end of the middle bracket segment, and the portion of the fifth wave trough is not simultaneously connected to the portion of the fourth wave peak and the fifth wave trough of other fifth bracket unit rings in the middle bracket segment.

8. The support structure according to claim 2, characterized in that: The peak width of the fifth peak is greater than the stent width of the fifth stent unit ring.

9. The support structure according to claim 8, characterized in that: The peak width of the fifth peak is 1.1 to 3 times the width of the fifth bracket unit ring.

10. A medical stent, characterized in that: The medical stent comprises the stent structure according to any one of claims 1 to 9, a polymer layer is disposed on at least a portion of the surface of the stent structure, and a drug coating is disposed on at least a portion of the surface of the polymer layer.

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