A bare stent subunit and a bare stent

Abstract

This invention discloses a bare stent subunit and a bare stent, belonging to the field of medical device technology. It includes spaced-apart crests and troughs, inclined beams, and a closed-loop structure. One end of the inclined beam is connected to the crest, and the other end is connected to the trough. The crests, troughs, and / or the inclined beam extend circumferentially to form at least one ring. The closed-loop structure is disposed on at least one of the crests, troughs, and inclined beams. By providing a closed-loop structure on the crests, troughs, and / or inclined beams, this invention allows for the connection of different bare stent subunits to be connected to the closed-loop structure using flexible connectors when assembling the bare stent subunits into a bare stent. This improves the connection stability between the bare stent subunits, ensures the overall shape and dimensional accuracy of the bare stent, avoids placing the bare stent under abnormal stress conditions that could affect its fatigue performance, and prevents structural damage to the bare stent.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a bare stent subunit and a bare stent. Background Technology

[0002] The aorta, a vital component of the circulatory system, possesses a complex and intricate three-layered structure: the intima, media, and adventitia. This structural feature plays a crucial role in maintaining the normal physiological function of the aorta. However, when a tear occurs in the aortic intima, blood can enter the aortic media and, driven by pulse pressure, extend along the long axis of the aorta, forming aortic dissection (AD). Aortic dissection is an extremely dangerous cardiovascular disease with a rapid onset, rapid progression, and very high mortality rate, posing a serious threat to human health.

[0003] Aortic dissection is classified into type A and type B based on its pathological characteristics and treatment needs. For type A aortic dissection, surgical treatment is currently the primary approach to completely repair the damaged aortic wall. For type B aortic dissection, endovascular treatment is widely recommended due to its advantages of minimal invasiveness and rapid recovery. The core of endovascular treatment lies in the precise implantation of a covered stent into the blood vessel using a delivery device to seal the proximal tear of the dissection, thereby restoring normal blood flow to the aorta.

[0004] However, in actual treatment, if the dissection involves a long area or distal branch vessels, it is often difficult to effectively manage the distal portion. This is because the implantation length of covered stents is limited; excessive length may affect the blood supply to the intercostal arteries, thereby increasing the risk of postoperative paraplegia. To improve distal blood supply, some techniques attempt to expand the true lumen by implanting bare-metal stents distally. Although the distal tear may still receive continuous blood perfusion, this method does not obstruct the blood supply to the distal intercostal arteries and branch vessels. The use of bare-metal stents alleviates the problem of distal blood supply to some extent.

[0005] However, in known technologies, during delivery or after implantation, the connectors and the fixed positions of the bare stent subunits are prone to slippage. This slippage not only affects the overall shape and dimensional accuracy of the bare stent but also places it under abnormal stress, thereby reducing its fatigue performance. Over time, the stent is prone to structural damage, leading to treatment failure or even more serious complications.

[0006] Therefore, how to ensure the effective expansion of the true lumen by the bare stent while solving the problem of its connection stability has become a pressing technical challenge in the field of endovascular treatment of aortic dissection. Summary of the Invention

[0007] The purpose of this invention is to provide a bare support subunit and a bare support to solve the problems existing in the prior art. By setting a closed-loop structure on the crests, troughs and / or inclined beams, when the bare support subunits are assembled into a bare support, flexible connectors can be used to connect different bare support subunits to the closed-loop structure. This can improve the connection stability between the bare support subunits, ensure the overall shape and dimensional accuracy of the bare support, avoid the bare support being under abnormal stress and affecting its fatigue performance, and prevent the bare support from structural damage.

[0008] To achieve the above objectives, the present invention provides the following solution:

[0009] The present invention provides a bare support subunit, including spaced crests and troughs, inclined beams and a closed-loop structure. One end of the inclined beam is used to connect to the crest, and the other end of the inclined beam is used to connect to the trough. The crests, the troughs and / or the inclined beams extend circumferentially to form at least one ring. The closed-loop structure is disposed on at least one of the crests, the troughs and the inclined beams.

[0010] In one embodiment, the crests, the inclined beams, and the troughs are repeatedly arranged to form a ring structure connected end to end.

[0011] In one embodiment, the annular structure is connected at both ends by means of sleeve riveting, welding, or micro-spring winding.

[0012] In one embodiment, the crests, the inclined beams, and the troughs are repeatedly arranged to form an open-loop structure with disconnected beginnings and ends.

[0013] In one embodiment, the open-loop structure is a spiral structure.

[0014] In one embodiment, the closed-loop structure is a circular closed-loop or a spiral closed-loop, wherein the spiral closed-loop includes a single layer or multiple layers of spirals.

[0015] In one embodiment, the closed-loop structures are axially offset from each other in the bare support subunits.

[0016] The present invention also provides a bare stent, comprising one or more bare stent sub-units as described above and a flexible connector, wherein the bare stent sub-units are arranged axially; the flexible connector is connected to the closed-loop structure of different bare stent sub-units.

[0017] In one embodiment, the flexible connector connects the closed-loop structure of the different bare support subunits along the axial and / or circumferential directions.

[0018] In one embodiment, the flexible connector includes interlocking stretchable structures and / or the flexible connector is elastic.

[0019] The present invention achieves the following technical effects compared to the prior art:

[0020] In addition to crests, troughs, and inclined beams, the bare support subunits of this invention also feature a closed-loop structure. By incorporating the closed-loop structure on the crests, troughs, and / or inclined beams, flexible connectors can be used to connect different bare support subunits when they are assembled into a bare support. Due to the constraints of the closed-loop structure, the connection positions of the flexible connectors are relatively fixed, which improves the connection stability between the bare support subunits, ensures the overall shape and dimensional accuracy of the bare support, prevents the bare support from being under abnormal stress conditions that could affect its fatigue performance, and avoids structural damage to the bare support. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a bare support subunit with a ring-shaped structure connected end to end in an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram illustrating the use of sleeve connection when connecting the beginning and end in an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of a bare support subunit with an open-loop structure that is disconnected at both ends in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the planar unfolding of the spiral structure of the bare support subunit in an embodiment of the present invention;

[0026] Figure 5 This is a schematic diagram of a closed-loop structure in the form of a complete circle in an embodiment of the present invention;

[0027] Figure 6 This is a schematic diagram of a closed-loop structure in a spiral shape, as shown in an embodiment of the present invention.

[0028] Figure 7 This is a schematic diagram before bending when the closed-loop structure of the inclined beam in this embodiment of the invention is a spiral closed loop made of metal wire.

[0029] Figure 8 This is a schematic diagram showing the bent state of the inclined beam in this embodiment of the invention when the closed-loop structure is a spiral closed loop made of metal wire.

[0030] Figure 9This is a schematic diagram of one form of the closed-loop structure of the peaks and troughs in an embodiment of the present invention;

[0031] Figure 10 This is a schematic diagram of another form of the closed-loop structure of the peaks and troughs in an embodiment of the present invention;

[0032] Figure 11 This is a schematic diagram of the bare support subunit of the bare support, in which the flexible connectors are connected in a ring structure along the circumferential direction in an embodiment of the present invention.

[0033] Figure 12 for Figure 11 Another perspective illustration;

[0034] Figure 13 This is a schematic diagram of the flexible connector being inserted and wound around the closed-loop structure in an embodiment of the present invention;

[0035] Figure 14 This is a schematic diagram of the bare support (with the first and last ends in a free state) of the bare support subunit of the flexible connector connected axially in an open-loop structure in an embodiment of the present invention before bending.

[0036] Figure 15 for Figure 14 Another perspective illustration;

[0037] Figure 16 This is a schematic diagram of the bare support (with its first and last ends connected to the inclined beam) of the bare support subunit of the flexible connector connected axially in an open-loop structure in an embodiment of the present invention before bending.

[0038] Figure 17 for Figure 16 Another perspective illustration;

[0039] Figure 18 This is a schematic diagram of the bare support (with its first and last ends connected to the inclined beam) of the bare support subunit with the flexible connectors connected axially in an open-loop structure according to an embodiment of the present invention after bending.

[0040] Figure 19 This is a schematic diagram of one structural form of the flexible connector in an embodiment of the present invention;

[0041] Figure 20 for Figure 19 A schematic diagram of a flexible connector on one side of the middle section;

[0042] Figure 21 This is a schematic diagram of another structural form of the flexible connector in an embodiment of the present invention;

[0043] Figure 22 for Figure 21 A schematic diagram showing that only one side of the connecting rope has an anti-detachment structure.

[0044] Among them, 1. crest; 2. trough; 3. inclined beam; 4. closed-loop structure; 5. flexible connector; 6. sleeve;

[0045] 41. Circular closed loop; 42. Spiral closed loop;

[0046] 51. First connecting rope; 511. First knot; 512. First anti-derailment structure; 52. Second connecting rope; 521. Second knot; 522. Second anti-derailment structure. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] The purpose of this invention is to provide a bare support subunit and a bare support to solve the problems existing in the prior art. By setting a closed-loop structure on the crests, troughs and / or inclined beams, when the bare support subunits are assembled into a bare support, flexible connectors can be used to connect different bare support subunits to the closed-loop structure. This can improve the connection stability between the bare support subunits, ensure the overall shape and dimensional accuracy of the bare support, avoid the bare support being under abnormal stress and affecting its fatigue performance, and prevent the bare support from structural damage.

[0049] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] like Figures 1-22As shown, this invention provides a bare stent subunit, including spaced-apart crests 1 and troughs 2, a sloping beam 3, and a closed-loop structure 4. One end of the sloping beam 3 is connected to the crest 1, and the other end is connected to the trough 2. Thus, the crest 1, trough 2, and sloping beam 3 combine to form a waveform structure. A single bare stent subunit may include one or more complete waveform structures, or it may include partially incomplete waveform structures, such as missing half or a whole crest 1 (or trough 2 or sloping beam 3), or one of the waveform structures having only half a waveform, etc. It should also be noted that crest 1 and trough 2 are merely names; they can have the same or different structures. If the orientation of the bare stent subunit is reversed, crest 1 may be located at the position of trough 2, and trough 2 may be located at the position of crest 1. The crest 1, trough 2, and / or sloping beam 3 extend circumferentially to form at least one ring. The ring-shaped bare stent subunit, when combined in one or more ways, can be used to form a bare stent to achieve circumferential support within the blood vessel. The location of the closed-loop structure 4 is not specifically constrained. The closed-loop structure 4 can be set on one of the crests 1, troughs 2, and inclined beams 3, or on any two of them, or on all three. The closed-loop structure 4 can be formed by bending the crests 1, troughs 2, or inclined beams 3 themselves, or it can be a structure connected by welding, bonding, or other methods.

[0051] In addition to the crests 1, troughs 2, and inclined beams 3, the bare support subunit of this invention also has a closed-loop structure 4. By setting the closed-loop structure 4 on the crests 1, troughs 2, and / or inclined beams 3, when the bare support subunits are assembled into a bare support, different bare support subunits can be connected to the closed-loop structure 4 using flexible connectors 5. Due to the constraint of the closed-loop structure 4, the connection position of the flexible connectors 5 is relatively fixed, which can improve the connection stability between the bare support subunits, ensure the overall shape and dimensional accuracy of the bare support, avoid the bare support being in an abnormal stress state that would affect its fatigue performance, and prevent the bare support from structural damage.

[0052] In one implementation, such as Figure 1As shown, the wave crest 1, inclined beam 3, and wave trough 2 are repeatedly arranged to form a ring structure connected end to end. The wave structure (including one wave crest 1, one wave trough 2, and four inclined beams 3) contained in the ring structure can be an integer number of wave structures or a non-integer number of wave structures. Usually, the wave structure can be made first and then connected end to end. The closed loop structure 4 can be set only on the same side of the axial direction of the ring structure, or it can be set on both sides of the axial direction of the ring structure. When the closed loop structure 4 is set, it is located in the same annular plane as the ring structure. The closed loop structure 4 itself can also have a certain curvature to minimize the radial space occupied by the closed loop structure 4. At the same time, it can also avoid serious medical accidents such as bare stent displacement, instrument delivery failure, or even inability to detach when pushing guidewires, catheters, or delivery devices into the closed loop structure 4 during subsequent surgery.

[0053] In one embodiment, when the bare support subunits are connected into a ring structure, the beginning and end of the ring structure are connected by means of sleeve 6 riveting, welding or micro-spring winding. Figure 2 The diagram shows a structure using sleeve 6 for riveting. Of course, sleeve 6 can also be removed and welding can be performed directly (e.g., using laser welding). Alternatively, two threaded ends (starting and ending) can be butted or overlapped and then riveted or welded using metal sleeve 6 to form a ring structure and securely connect the bare support subunit. Generally, the threaded ends (starting or ending) can be riveted or welded to the adjacent inclined beam 3 using sleeve 6.

[0054] In one implementation, such as Figure 3 As shown, the wave crest 1, inclined beam 3, and wave trough 2 are repeatedly arranged to form an open-loop structure with disconnected ends. The number of wave structures composed of wave crest 1, wave trough 2, and inclined beam 3 included in the open-loop structure can be an integer or a non-integer number. The closed-loop structure 4 can be set only on the same side of the axial direction of the open-loop structure, or it can be set on both sides of the axial direction of the open-loop structure. When setting the closed-loop structure 4, it is located in the same annular plane as the open-loop structure. The closed-loop structure 4 itself can also have a certain curvature to minimize the radial space occupied by the closed-loop structure 4. At the same time, it can also avoid serious medical accidents such as bare stent displacement, instrument delivery failure, or even inability to detach when pushing guidewires, catheters, or delivery devices into the closed-loop structure 4 during subsequent surgery.

[0055] In one embodiment, the open-loop structure is a spiral structure, meaning that one or more waveform structures forming the open-loop structure extend along the spiral direction, ultimately forming a bare support subunit with a single or multiple turns of spiral structure. For a bare support subunit with a multi-turn spiral structure or a bare support formed therefrom, after heat treatment and shaping, due to the presence of peaks 1 (or troughs 2), the sleeve 6 may not be able to reach the inclined beam 3 adjacent to the wire end (first or last end), thus making it impossible to connect the wire end to the inclined beam 3. In this invention, during the winding process, a sleeve 6 is reserved at the position of the inclined beam 3 adjacent to the wire end. After heat treatment and shaping, the wire end is inserted into the reserved sleeve 6 and riveted, thereby solving or avoiding the aforementioned problem of not being able to connect the wire end to the inclined beam 3.

[0056] In one implementation, such as Figure 5 As shown, the closed-loop structure 4 is a fully circular closed loop 41, which can be formed using metal laser engraving. Alternatively, as... Figure 6 As shown, the closed-loop structure 4 is a spiral closed-loop 42. In this case, it can be formed by winding metal wire. The wound spiral closed-loop 42 can include a single layer or multiple layers of spiral. Multiple layers of spiral can further improve the flexibility of the bare support subunit.

[0057] In one embodiment, in the bare support subunit, the closed-loop structure 4 of the inclined beam 3 is a spiral closed loop 42 made of wound metal wire. In this case, the inclined beam 3 has a certain axial bending capacity, as before bending... Figure 7 As shown, after bending... Figure 8 As shown, by setting the spiral closed loop 42, the minimum bending unit of the bare support formed by the bare support sub-unit is reduced from the ring height of the bare support sub-unit (the height of the crest 1 to the trough 2) to the height of the closed loop structure 4 of the crest 1 (or trough 2) to the inclined beam 3, thereby improving the overall flexibility of the bare support.

[0058] In one implementation, such as Figure 1 , Figure 3 and Figure 4 As shown, crest 1 and trough 2 can be open loops with a certain bending angle and bending radius. The bending radius range is generally 0.3mm to 3mm, which enables the bare support subunit to have radial contraction and expansion functions while having a certain appropriate radial support force.

[0059] In one embodiment, in the bare support subunit, the closed-loop structure 4 of the crest 1 (or trough 2) is a spiral closed loop 42 made of wound metal wire. In this case, it is possible to form a closed loop such as... Figure 9 The closed-loop structure 4 shown is located outside the intersection of the inclined beam 3, and can also form a structure like... Figure 10The closed-loop structure 4 shown is located inside the intersection of the inclined beam 3. By adjusting parameters such as the bending radius, number of spiral turns, spiral angle, and spiral position (inner or outer) of the spiral closed-loop 42, the radial support force of the bare support can be adjusted. At the same time, the spiral closed-loop 42 at the peak 1 (or trough 2) position can reduce the stress when the bare support is installed into the conveyor for radial compression, thus avoiding plastic deformation.

[0060] In one embodiment, a plurality of closed-loop structures 4 are provided on the bare stent subunit. The closed-loop structures 4 are staggered from each other in the axial direction of the bare stent subunit, which can reduce the compression diameter of the bare stent formed by the bare stent subunit when it is compressed into the delivery sheath, making it easier to deliver to the target vascular lesion site.

[0061] like Figures 11-21 As shown, the present invention also provides a bare stent, comprising one or more bare stent sub-units as described above and a flexible connector 5. The bare stent sub-units are arranged axially, and adjacent bare stent sub-units are connected by the flexible connector 5. The flexible connector 5 can be made of suture, metal wire, or metal cable, etc., wherein the suture can be polyester suture or suture woven from ultra-high molecular weight polyethylene fiber, etc. The bare stent sub-units can be made of, for example,... Figure 1 The ring structure shown or as Figure 3 The open-loop structure shown (in which the bare support is a continuous spiral) has the following characteristics: For the former, axial support capacity is weak, and radial misalignment may occur. Straight or S-shaped longitudinal ribs can be added between bare support sub-units to connect adjacent sub-units, thereby improving support capacity. For the latter, the bare support sub-units are supported not only by the flexible connector 5 but also by the sub-units themselves, exhibiting good support stability in both axial and radial directions. When connecting, the flexible connector 5 connects to the closed-loop structure 4 of different bare support sub-units. The closed-loop structure 4 constrains or limits the position of the flexible connector 5, ensuring the stability of the connection structure and preventing changes in the overall shape and dimensional accuracy of the bare support due to displacement of the flexible connector 5.

[0062] In one embodiment, the flexible connector 5 passes through or is bound to the closed-loop structure 4 of the inclined beam 3 of the bare support subunit, and is connected to the crest 1 (or trough 2) of the adjacent bare support subunit, or to the closed-loop structure 4 of the adjacent bare support subunit, or to both. Because the flexible connector 5 passes through or is bound to the closed-loop structure 4, the flexible connector 5 will not slide on the smooth surface of the bare support subunit under stress, thereby preventing the bare support from being in an abnormal stress state such as abnormal stacking or folding, and preventing fatigue fracture of the bare support.

[0063] In one implementation, such as Figure 11 and Figure 12As shown, the flexible connector 5 connects the closed-loop structure 4 of different bare support sub-units circumferentially. (As shown...) Figures 14-18 As shown, the flexible connector 5 connects the closed-loop structure 4 of different bare stent subunits along the axial direction. Of course, in the same bare stent, the flexible connector 5 can be set both circumferentially and axially. The flexible connector 5, whether set axially or circumferentially, can enhance the connection stability between bare stent subunits. When the flexible connector 5 is set axially, the flexible connector 5 can have a certain elongation capacity, or the flexible connector 5 can have a certain elasticity, so that when the bare stent adapts to the tortuous shape of the blood vessel, the flexible connector 5 on the large curvature side can be axially elongated, so that the distance between the bare stent subunits on the large curvature side increases, further improving its compliance, reducing the straightening force of the bare stent, avoiding stimulation of the proximal and distal blood vessel walls due to poor compliance and high straightening force of the bare stent, and preventing new stent-induced ruptures.

[0064] The axial (longitudinal) connection of the flexible connector 5 to the closed-loop structure 4 has the following advantages: 1) After the bare stent is implanted, the flexible connector 5 can better conform to the vessel wall, solving the problem of the flexible connector 5 not conforming to the wall after radial compression when the bare stent is connected circumferentially (laterally). This avoids medical accidents caused by guidewires, catheters, etc. entering the non-conforming flexible connector 5. 2) The axial expansion and contraction of the spiral bare stent is limited within a reasonable range, giving the bare stent both flexibility and morphological stability. 3) Due to the design of the closed-loop structure 4, the flexible connector 5 will not slip off from the bare stent body, causing abnormal morphology of the bare stent. 4) Even if the flexible connector 5 may bend to form a ring on the small bend side, since the ring is generally parallel to the axis of the bare stent, it will not be allowed to enter the ring when pushing guidewires, catheters, or delivery devices during subsequent surgery, thus avoiding serious medical accidents such as bare stent displacement, device delivery failure, or even inability to detach.

[0065] In one embodiment, combined with Figure 13 As shown, the flexible connector 5 is interwoven, wrapped, or knotted into the closed-loop structure 4 of the inclined beam 3 of the adjacent bare support sub-unit, so that the crests 1 and troughs 2 of the bare support sub-unit are both in a free state, making it more compliant than the technical solution where the crests 1 and troughs 2 are bound. When the crests 1 and troughs 2 are in a free state and the bare support sub-units overlap each other, the compliant bending resistance of the bare support is improved.

[0066] In one implementation, such as Figures 19-22As shown, the flexible connector 5 includes a stretchable structure that is nested within each other. For example, it includes a first connecting rope 51 and a second connecting rope 52. The first connecting rope 51 is provided with a first knot 511, and the second connecting rope 52 is provided with a second knot 521. The first knot 511 is nested on the second connecting rope 52, and the second knot 521 is nested on the first connecting rope 51, forming a stretchable flexible connector 5. When the flexible connector 5 uses metal wire or metal cable, the first knot 511 and the second knot 521 have good stability and can prevent them from coming off each other (e.g., Figure 19 (As shown); When the flexible connector 5 uses suture thread, due to its weaker texture, a first anti-loosening structure 512 can be provided only at the end of the first connecting rope 51 without providing a first knot 511. In this case, the second knot 521 of the second connecting rope 52 is not easily opened due to friction (as shown). Figure 22 (As shown), or, a second anti-detachment structure 522 is provided only at the end of the second connecting rope 52 without a second knot 521. In this case, the first knot 511 of the first connecting rope 51 is not easily opened due to friction. Alternatively, the first knot 511 and the first anti-detachment structure 512, as well as the second knot 521 and the second anti-detachment structure 522, are all provided (as shown). Figure 21 As shown in the diagram, the maximum extension length of the first connecting rope 51 and the second connecting rope 52 is limited by the above method to prevent them from separating. The flexible connector 5 can also be made of an elastic material, so that the flexible connector 5 itself is elastic and can extend and retract within a certain range.

[0067] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A bare stent, characterized in that, include: One or more bare support sub-units are arranged axially; each bare support sub-unit includes spaced-apart crests and troughs, inclined beams, and closed-loop structures. One end of each inclined beam is connected to a crest, and the other end is connected to a trough. The crests, troughs, and / or the inclined beams extend circumferentially to form at least one ring. The closed-loop structure is disposed on the inclined beams. The closed-loop structure is a helical closed-loop. The minimum bending unit of the bare support sub-unit is the height of the closed-loop structure from the crest to the inclined beam, or the height of the closed-loop structure from the trough to the inclined beam. And a flexible connector, which is axially and / or circumferentially connected to the closed-loop structure of different bare support subunits; the flexible connector includes a stretchable structure that is nested with each other, including a first connecting rope and a second connecting rope, the first connecting rope having a first knot, the second connecting rope having a second knot, the first knot being nested on the second connecting rope, and the second knot being nested on the first connecting rope, forming the stretchable flexible connector.

2. The bare stent according to claim 1, characterized in that: The wave crests, the inclined beams, and the wave troughs are repeatedly arranged to form a ring structure that is connected end to end.

3. The bare stent according to claim 2, characterized in that: The annular structure is connected at both ends by means of sleeve riveting, welding, or micro-spring winding.

4. The bare stent according to claim 1, characterized in that: The wave crests, the inclined beams, and the wave troughs are repeatedly arranged to form an open-loop structure with disconnected beginnings and ends.

5. The bare stent according to claim 4, characterized in that: The open-loop structure has a spiral shape.

6. The bare stent according to claim 1, characterized in that: The closed-loop structures are offset from each other along the axial direction of the bare support sub-units.

7. The bare stent according to claim 1, characterized in that: The spiral closed loop includes a single layer or multiple layers of spirals.

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