Covered stent and stent system
By designing the ring and limiting rod mechanism of the covered stent, the problems of difficult overselective reconstruction of branch stents and occupation of aortic lumen space during endovascular treatment were solved. Successful overselection and anchoring were achieved in narrow aortic lumens, reducing the risk of endoleak and improving the safety and effectiveness of treatment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- LIFETECH SCI (SHENZHEN) CO LTD
- Filing Date
- 2024-12-31
- Publication Date
- 2026-06-09
AI Technical Summary
Existing technologies for endovascular treatment of aortic aneurysms and aortic dissections involving branch vessels present challenges such as difficulty in superselective reconstruction of branch stents and the occupation of aortic lumen space, especially in cases of narrow aortic lumens.
A covered stent was designed, including a main stent and a branch stent. The branch stent is connected to the main stent by a ring. The branch stent is compressed during the implantation process using a limiting rod to ensure smooth superselection in the narrow aortic lumen. After implantation, the compression is released, allowing the branch stent to expand naturally and provide anchoring length without occupying aortic lumen space.
This technique enables successful overselection of branch vessels within narrow aortic lumens, ensuring anchorage length without occupying aortic space, reducing the risk of endoleak, and improving the safety and effectiveness of treatment.
Smart Images
Figure CN224331078U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of medical devices, and in particular to a covered stent and stent system. Background Technology
[0002] Aortic aneurysms and aortic dissections are serious diseases that threaten human life. Without prompt treatment, these aneurysms and dissections will continue to grow, eventually rupturing and causing severe complications and death. With the increasing number of patients with hypertension, hyperlipidemia, and hyperglycemia, the incidence of aortic aneurysms and aortic dissections is also rising significantly. Traditional open surgery for aortic aneurysms and aortic dissections is highly invasive, has a high mortality rate, long operation time, high postoperative complication rate, and high surgical difficulty. Endovascular treatment, on the other hand, is less invasive, has fewer postoperative complications, shorter operation time, and lower surgical difficulty, and has gradually become the main method for treating aortic aneurysms and aortic dissections. By implanting a covered stent in the aorta, the vascular lesion is isolated outside the covered stent, restricting blood flow through the stent and thus protecting the blood vessel.
[0003] For aortic aneurysms and aortic dissections involving branch vessels, such as thoracoabdominal aortic dissections, existing branch stenting technology presents a technical challenge during endovascular treatment: the narrow aortic lumen makes superselective reconstruction of branch stents difficult. For these cases with narrow aortic lumen in the corresponding branch artery region, one approach is to use fenestrated stents. Fenestrated stents do not occupy main lumen space and are easier to superselectively reconstruct branches. However, fenestrated stents have a higher risk of endoleak due to the inability to guarantee stable anchorage with external branches. Another approach is to set the branch stent as an embedded branch. However, embedded branches occupy part of the already narrow aortic lumen, further reducing the space in the corresponding branch artery region, which is detrimental to main lumen blood flow and affects blood supply. Utility Model Content
[0004] One technical problem solved by this invention is how to provide a covered stent that can ensure that the external stent connected to the branch blood vessel has a certain anchoring length, while the branch stent does not occupy the space of the aortic lumen.
[0005] This utility model provides a film-coated stent, which includes a main stent and a branch stent. The branch stent includes a first end and a second end, which are opposite to each other. The first end is connected to one side of the main stent, and the lumen of the branch stent is connected to the lumen of the main stent. The branch stent includes a branch support and a branch film, which covers the branch support. The branch support includes an elastic element that extends spirally from the first end toward the second end. The elastic element can be compressed along the axial direction of the branch stent. The film-coated stent also includes at least one ring, and one of the at least one ring is disposed at the end of the branch stent away from the main stent.
[0006] In one embodiment, the main support includes a main waveband and a main film, the main film covering the main waveband, and the main film including a window; the first end is connected to the window circumferentially thereon.
[0007] In one embodiment, the branch support is spring-shaped, and the radial dimension of the branch support gradually decreases from the first end toward the second end.
[0008] In one embodiment, at least one of the rings includes a first ring, a second ring, a third ring, and a fourth ring. The first ring is disposed on the distal end of the window or on the distal end of a first end. The second ring is disposed on the proximal end of the window or on the proximal end of the first end, and both the first and second rings are close to the edge of the window. The third and fourth rings are both disposed on the second end, with the third ring disposed on the distal end of the second end and the fourth ring disposed on the proximal end of the second end.
[0009] In one embodiment, the first ring and the second ring are located on the same axial line of the main support, and the axial line passes through the center of the window; the third ring and the first ring are on the same axial line of the branch support, and the fourth ring and the second ring are on the same axial line of the branch support.
[0010] In one embodiment, the branch support is spring-shaped and extends spirally from the first end toward the second end. The branch support includes adjacent first and second spiral portions in the direction from the first end toward the second end, and the outer diameter of the second spiral portion is smaller than the inner diameter of the first spiral portion.
[0011] In one embodiment, the branch support further includes a third helical portion adjacent to the second helical portion and closer to the second end, wherein the outer diameter of the third helical portion is smaller than the inner diameter of the second helical portion.
[0012] In one embodiment, the covered stent further includes an embedded stent. The main stent includes a first segment, a transition segment, and a second segment from the proximal end to the distal end. The diameter of the first segment is larger than the diameter of the second segment. The diameter of the transition segment decreases from the proximal end to the distal end. The embedded stent extends from the transition segment toward the proximal end. The branch stent is disposed in the second segment.
[0013] In one embodiment, the support system includes a conveying device and a film-coated support as described above. The conveying device includes a limiting rod that extends axially outward along the main support and passes sequentially through a first ring, a third ring, a fourth ring, and a second ring from the distal end to the proximal end, such that the limiting rod compresses the branch support along the axial direction of the branch support.
[0014] In one embodiment, the delivery device further includes a sheath core assembly, a support rod, and a sheath tube, the sheath core assembly, the support rod, and the sheath tube being sequentially sleeved from the inside out, the support rod including at least three channels extending axially.
[0015] One technical effect of an embodiment of this utility model is that the covered stent provided by this utility model is equipped with a buckle. When the covered stent is loaded into the stent system, the buckle can be used to compress the branch stent along the axial direction of the branch stent, which facilitates superselection of branch vessels. After superselection is completed, the axial compression of the branch stent can be released, so that the branch stent is in a natural expansion state along the axial direction of the branch stent, so as to ensure that the external small stent connected to the branch vessel has a certain anchoring length. At the same time, the branch stent does not occupy the space of the aortic lumen. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the structure of the film-coated support in one embodiment of the present invention;
[0017] Figure 2 for Figure 1 Enlarged view of point A in the middle;
[0018] Figure 3 A schematic diagram showing the compression of the branch support along its own axis when the limiting rod passes through the branch support of the covered stent in one embodiment of the present invention.
[0019] Figure 4 for Figure 3 Enlarged view of point B in the middle;
[0020] Figure 5 This is a schematic diagram of the branch support structure in another embodiment of the present invention;
[0021] Figure 6 This is a schematic diagram of the structure of the film-coated support in another embodiment of the present invention;
[0022] Figure 7 This is a schematic diagram of the structure of the film-coated support in another embodiment of the present invention;
[0023] Figure 8 This is a schematic diagram of the support system in one embodiment of the present invention;
[0024] Figure 9 This is a structural schematic diagram of the support rod from an axial perspective in one embodiment of the present invention.
[0025] 100. Support system;
[0026] 10. Laminated support frame; 11. Main support frame; 111. Main waveguide; 112. Main laminated frame; 1121. Window; 113. First section; 114. Transition section; 115. Second section; 116. Connecting section; 117. Third section;
[0027] 12. Branch support; 121. First end; 122. Middle section; 123. Second end; 124. Branch support; 1241. First spiral part; 1242. Second spiral part; 1243. Third spiral part; 125. Branch coating; 13. First bare wave coil; 14. First ring buckle; 15. Second ring buckle; 16. Third ring buckle; 17. Fourth ring buckle; 18. Embedded support; 20. Conveying device; 21. Sheath core assembly; 22. Support rod; 221. First channel; 222. Second channel; 223. Third channel; 23. Sheath tube; 24. Bundle diameter guide wire; 241. Pull ring buckle; 25. Limiting rod; 26. Guide head. Detailed Implementation
[0028] To facilitate understanding of this utility model, a more complete description will be given below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of this utility model. However, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this utility model.
[0029] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "inner," "outer," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.
[0030] This utility model provides a film-coated support 10, such as Figure 1 As shown, the membrane support 10 includes a main support 11 and a branch support 12. The main support 11 includes a main wave loop 111 and a main membrane 112, with the main membrane 112 covering the main wave loop 111. The main wave loop 111 is a ring structure formed by connecting multiple waveform units end to end. Here, a waveform unit refers to a single-wave structure composed of wave crests, wave rods, and wave troughs, and the shape of the waveform unit is not limited. Each main wave loop 111 can be a regular ring structure formed by multiple waveform units of equal height, or an irregular ring structure including high and low waves formed by waveform units of different wave heights. Adjacent main wave loops 111 can all be regular ring structures, or all be irregular ring structures including high and low waves, or a combination of two types of ring structures: regular ring structures and irregular ring structures including high and low waves. This is not limited here.
[0031] The main body covering 112 is a tubular structure with openings at both ends. Multiple main body wave coils 111 are arranged axially and connected through the tubular main body covering 112 to form a tubular main body support 11. Further, the covering support 10 also includes a first bare wave coil 13, the distal end of which is connected to the proximal end of the main body support 11, and the first bare wave coil 13 is at least partially exposed outside the main body covering 112.
[0032] A branch support 12 is disposed on one side of the main support 11, and is connected to the axial side of the main support 11, with the lumen of the branch support 12 communicating with the lumen of the main support 11. The main covering 112 includes a window 1121, and one end of the branch support 12 is circumferentially connected to the window 1121, allowing the lumen of the branch support 12 to communicate with the lumen of the main support 11.
[0033] The branch bracket 12 includes a first end 121, a middle section 122, and a second end 123. The first end 121 and the second end 123 are oppositely disposed at both ends. The middle section 122 extends between the first end 121 and the second end 123. The first end 121 of the branch bracket 12 is the end closer to the main bracket 11 and is connected to one side of the main bracket. Further, the first end 121 is connected to the window 1121 circumferentially. The second end 123 of the branch bracket 12 is the end of the branch bracket 12 away from the main bracket 11. The window 1121 is circular, and the opening of the first end 121 of the branch bracket 12 is also circular, so as to facilitate the circumferential connection of the second end 123 of the branch bracket 12 to the window 1121, thereby connecting the branch bracket 12 to the main bracket 11.
[0034] The branch support 12 also includes a branch support 124 and a branch coating 125. The branch coating 125 covers the branch support 124. The branch support 124 includes an elastic member extending spirally from a first end 121 toward a second end 123. This elastic member can be compressed along the axial direction of the branch support 12. Figure 4 As shown, the axial direction of the branch support 12 refers to the direction from the first end 121 to the second end 123 or from the second end 123 to the first end 121. In one embodiment, the branch support 124 is spring-shaped, and the openings of the first end 121 and the second end 123 are both circular. The diameter of the opening at the first end 121 is larger than the diameter of the opening at the second end 123. Furthermore, the radial dimension of the branch support 124 gradually decreases from the first end 121 towards the second end 123.
[0035] The covered stent also includes at least one ring, with at least one ring disposed at the end of the branch stent away from the main stent. In one embodiment, the covered stent 10 further includes a first ring 14, a second ring 15, a third ring 16, and a fourth ring 17. The first ring 14 is disposed at the distal end of the window 1121 or at the distal end of the first end 121; the second ring 15 is disposed at the proximal end of the window 1121 or at the proximal end of the first end 121, and both the first ring 14 and the second ring 15 are close to the edge of the window 1121; the third ring 16 and the fourth ring 17 are both disposed at the second end 123, wherein the third ring 16 is disposed at the distal end of the second end 123, and the fourth ring 17 is disposed at the proximal end of the second end 123, so that the first ring 14, the second ring 15, the third ring 16, and the fourth ring 17 can cooperate to... The limiting rod 25 passes sequentially through the first ring 14, the third ring 16, the fourth ring 17, and the second ring 15, causing the limiting rod 25 to compress the branch support 124 along the axial direction of the branch stent 12. This allows for easy superselection of branch vessels when the aortic lumen is narrow in the corresponding branch artery region during the implantation of the covered stent 10, while the branch support 124 remains compressed along the axial direction of the branch stent 12. After superselection, the axial compression of the branch support 124 by the limiting rod 25 can be released, allowing the branch stent 12 to naturally expand along the axial direction of the branch stent 12. This ensures that the external stent connected to the branch vessel has a certain anchoring length, while the branch stent 12 does not occupy the space of the aortic lumen. In one embodiment, the first ring 14 and the second ring 15 are located on the same axial line of the main support 11, and the axial line passes through the center of the window 1121; the third ring 16 and the first ring 14 are on the same branch axial line of the branch support 12, and the fourth ring 17 and the second ring 15 are on the same axial line of the branch support 12, wherein the axial direction of the main support 11 is along the direction of extension of the lumen of the main support 11, and the axial direction of the branch support 12 is along the direction of extension of the lumen of the branch support 12.
[0036] In one embodiment, the branch support 124 is spring-shaped and extends spirally from a first end 121 toward a second end 123. The branch support 124 includes adjacent first spiral portions 1241 and second spiral portions 1242 in the direction from the first end 121 toward the second end 123. The first spiral portion 1241 is closer to the first end 121 than the second spiral portion 1242, and the second spiral portion 1242 is closer to the second end 123 than the first spiral portion 1241. The outer diameter of the second spiral portion 1242 is smaller than the inner diameter of the first spiral portion 1241, so that when the branch support 12 is compressed axially, the second spiral portion 1242 can be pressed against the first spiral portion 1241. Within 41, it can be understood that the branch support 124 also includes a third helical portion 1243, which is adjacent to the second helical portion 1242 and closer to the second end 123. The outer diameter of the third helical portion 1243 is smaller than the inner diameter of the second helical portion 1242, so that when the branch support 124 is compressed in its axial direction, the helical portion near the second end 123 can enter the adjacent helical portion near the first end 121. On the one hand, this facilitates the compression of the branch support 12 in its axial direction, and on the other hand, it ensures that when the branch support 12 is compressed in its axial direction, the radial dimension of the main support 11 is not increased, thereby not increasing the loading volume.
[0037] In one embodiment, the covered stent 10 includes a main stent 11, embedded stents 18, and branch stents 12. The main stent 11 includes a first segment 113, a transition segment 114, and a second segment 115 from the proximal end to the distal end. The diameter of the first segment 113 is larger than the diameter of the second segment 115. The diameter of the transition segment 114 decreases from the proximal end to the distal end to facilitate the transition connection between the first segment 113 and the second segment 115. Two embedded stents 18 are provided, arranged parallel to each other along the axial direction, and both embedded stents 18 extend from the transition segment 114 towards the proximal end. Two branch stents 12 are provided, respectively located on both sides of the second segment 115. This facilitates superselection of renal artery branch vessels when the aortic lumen is narrow at the location corresponding to the renal artery in the abdominal aorta. At the same time, the branch stents 12 do not occupy the space of the aortic lumen in the corresponding renal artery branch region, ensuring blood flow in the main lumen. Furthermore, it ensures that the external stents connected to the renal artery branches have a certain anchorage length.
[0038] In one embodiment, the covered stent 10 further includes a connecting segment 116 and a third segment 117. The connecting segment 116 connects the second segment 115 and the third segment 117. The third segment 117 is located on the distal side of the connecting segment 116, and the diameter of the third segment 117 is larger than the diameter of the second segment 115. The diameter of the connecting segment 116 gradually increases from the proximal end to the distal end to facilitate the transition connection between the second segment 115 and the third segment 117. A branch stent 12 is connected to the second segment 115. The second segment 115 has a smaller diameter, which better accommodates the smaller aortic lumen. Given the smaller diameter of the second segment 115, the branch stent 12 can ensure the anchorage of the external small stent without occupying the main lumen space (and without affecting the main lumen blood flow).
[0039] This utility model also provides a support system, which includes a conveying device 20 and the aforementioned coated support 10. The conveying device 20 includes a semi-binding structure that can releasably bind the main support 11 so that the main support 11 can be radially compressed or released. The conveying device 20 also includes a sheath core assembly 21, a support rod 22, a sheath tube 23, a guide wire 24, and a handle assembly. The sheath core assembly 21 includes an inner sheath core and an outer sheath core, which are sequentially sleeved from the inside to the outside. Each pair of the inner sheath core, outer sheath core, and sheath tube 23 can move relative to each other axially. The support rod 22 is sleeved on the outside of the sheath core assembly 21. The conveying device 20 also includes a guide head 26, which is disposed at the distal end of the inner sheath core. The distal end of the support rod 22 and the proximal end of the guide head 26 are spaced apart to form a loading space for the coated support 10. The guide wire 24 is used to pass through the radial compression main support 11 (not shown in the figure) to achieve semi-binding of the main support 11, so as to facilitate precise positioning before the covered support 10 is released. The proximal end of the guide wire 24 is connected to a pull ring buckle 241 as a safety buckle. The pull ring buckle 241 is detachably fixed to the handle assembly. When it is necessary to release the semi-binding of the covered support 10, the safety buckle is first released from the handle assembly, and then the safety buckle is pulled back. The semi-binding structure opens, releasing the radial binding of the covered support 10 and allowing the covered support 10 to expand naturally.
[0040] The delivery device 20 also includes a limiting rod 25, which extends axially outward along the main stent 11 and passes sequentially through the first ring 14, the third ring 16, the fourth ring 17, and the second ring 15 from the distal end to the proximal end. This allows the limiting rod 25 to compress the branch support 124 along the axial direction of the branch stent 12. This allows for easy superselection of branch vessels during stent system implantation while the branch support 124 remains compressed along the axial direction of the branch stent 12. After superselection, the axial compression of the branch support 124 by the limiting rod 25 can be released, allowing the branch stent 12 to naturally expand along the axial direction of the branch stent 12. This ensures that the external stent connected to the branch vessel has a certain anchoring length, and the branch stent 12 does not occupy the space of the aortic lumen.
[0041] It is understandable that the hardness of the limiting rod 25 is greater than that of the branch support 124, so that the limiting rod 25 can limit the compressed branch support 124. When the limiting rod 25 passes through each ring in sequence, it can remain unbent, thereby limiting the compressed branch support 124 and maintaining its compressed state.
[0042] The support rod 22 includes at least three channels extending axially. In one embodiment, the support rod 22 includes a first channel 221, a second channel 222, and a third channel 223 extending axially. The first channel 221 allows the sheath core assembly 21 to pass through axially, the second channel 222 allows the guide wire 24 to pass through axially, and the third channel 223 allows the limiting rod 25 to pass through axially. This prevents the guide wire 24 and the limiting rod 25 from becoming entangled inside the support system, thereby affecting their respective release from the main support 11 or the branch support 12.
[0043] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above 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.
[0044] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.
Claims
1. A covered stent, characterized in that, The covered stent includes a main stent and a branch stent. The branch stent includes a first end and a second end, which are opposite to each other. The first end is connected to one side of the main stent, and the lumen of the branch stent is connected to the lumen of the main stent. The branch stent includes a branch support and a branch covering. The branch covering covers the branch support. The branch support includes an elastic element that extends spirally from the first end toward the second end. The elastic element can be compressed along the axial direction of the branch stent. The covered stent also includes at least one ring, and one of the at least one ring is disposed at the end of the branch stent away from the main stent.
2. The covered scaffold according to claim 1, characterized in that, The main support includes a main wave coil and a main film, the main film covering the main wave coil, and the main film including a window; the first end is connected to the window along its circumference.
3. The covered scaffold according to claim 1 or 2, characterized in that, The branch support is spring-shaped, and its radial dimension in the branch bracket gradually decreases from the first end toward the second end.
4. The covered scaffold according to claim 2, characterized in that, At least one of the rings includes a first ring, a second ring, a third ring, and a fourth ring. The first ring is disposed on the distal end of the window or on the distal end of a first end. The second ring is disposed on the proximal end of the window or on the proximal end of the first end, and both the first and second rings are close to the edge of the window. The third and fourth rings are both disposed on the second end, with the third ring disposed on the distal end of the second end and the fourth ring disposed on the proximal end of the second end.
5. The covered stent according to claim 4, characterized in that, The first and second rings are located on the same axial line of the main support, and the axial line passes through the center of the window; the third ring and the first ring are on the same axial line of the branch support, and the fourth ring and the second ring are on the same axial line of the branch support.
6. The covered stent according to claim 4, characterized in that, The branch support is spring-shaped and extends spirally from the first end toward the second end. The branch support includes an adjacent first spiral portion and a second spiral portion in the direction from the first end toward the second end. The outer diameter of the second spiral portion is smaller than the inner diameter of the first spiral portion.
7. The covered stent according to claim 6, characterized in that, The branch support also includes a third helical portion, which is adjacent to the second helical portion and closer to the second end. The outer diameter of the third helical portion is smaller than the inner diameter of the second helical portion.
8. The covered stent according to claim 1, characterized in that, The covered stent also includes an embedded stent. The main stent includes a first segment, a transition segment, and a second segment from the proximal end to the distal end. The diameter of the first segment is larger than the diameter of the second segment. The diameter of the transition segment decreases from the proximal end to the distal end. The embedded stent extends from the transition segment toward the proximal end. The branch stent is disposed in the second segment.
9. A support system, characterized in that, The support system includes a conveying device and a film-coated support as described in any one of claims 4-7. The conveying device includes a limiting rod that extends axially outward along the main support and passes through a first ring, a third ring, a fourth ring, and a second ring sequentially from the distal end to the proximal end, such that the limiting rod compresses the branch support along the axial direction of the branch support.
10. The support system according to claim 9, characterized in that, The conveying device further includes a sheath core assembly, a support rod, and a sheath tube, which are sequentially sleeved from the inside to the outside. The support rod includes at least three channels that extend axially.