Stent system

Abstract

The present application relates to the technical field of medical devices, and discloses a stent system, which comprises a covered stent and an adjusting structure, the covered stent comprises a first side and a second side in the circumferential direction, the adjusting structure comprises a first adjusting member, a locking sleeve and a limiting ring buckle, the limiting ring buckle is connected with the distal end of the first side, the distal end side of the locking sleeve is provided with an opening, the first adjusting member extends in the axial direction in the cavity of the locking sleeve and passes through the limiting ring buckle at the opening, so that the limiting ring buckle cannot slide out of the first adjusting member when being pulled. The limiting ring buckle is locked under the cooperation of the first adjusting member and the locking sleeve, when the covered stent is released into the blood vessel, the position of the distal end of the first side can be adjusted by pulling the limiting ring buckle, the first side of the covered stent is attached to the blood vessel wall, so that the included angle between the first side and the blood vessel wall can be reduced or eliminated, and the possibility of leakage of the covered stent is reduced.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and more particularly to a stent system. Background Technology

[0002] This section provides only background information related to the present invention and is not necessarily prior art.

[0003] Aortic aneurysm and aortic dissection are serious diseases that threaten human life. If left untreated, the aortic aneurysm and dissection will continue to grow and eventually rupture, causing serious complications and death. With the increasing number of patients with hypertension, hyperlipidemia and hyperglycemia, the incidence of aortic aneurysm and aortic dissection is also increasing significantly.

[0004] Endovascular aortic stent grafting involves implanting a stent graft in the aorta to isolate vascular lesions outside the stent graft and restrict blood flow through the stent graft, thereby protecting the blood vessel. It has been widely used for lesions such as aneurysms and aortic dissections in the thoracic and abdominal aortas, with definite efficacy, minimal trauma, rapid recovery, and few complications.

[0005] Current aortic stents, when there is a bend in the anchorage position, for example, Figure 1 As shown, the anchoring zone of the stent 10' used for the thoracic aorta is located at the aortic arch 20'. After the stent 10' is released, the proximal lesser curvature side is prone to the "bird's beak" phenomenon, that is, the lesser curvature side 11' of the stent 10' forms an angle α with the aortic arch wall 21'. Postoperatively, type I endoleak is prone to occur. In the long term, if not treated in time, the pressure inside the aortic aneurysm may continue to increase, which may cause the aneurysm to rupture, or the aortic dissection rupture may not be isolated, and the false lumen may not be thrombotic. Summary of the Invention

[0006] The purpose of this invention is to at least alleviate the problem of "bird's beak" phenomenon easily appearing on the lesser bend after stent deployment, which leads to a high likelihood of "I"-shaped endoleaks postoperatively. This objective is achieved through the following technical solution:

[0007] A first aspect of the present invention provides a stent system including a covered stent and an adjustment structure. The covered stent includes a first side and a second side circumferentially. The adjustment structure includes a first adjustment member, a locking sleeve, and a limiting ring. The limiting ring is connected to the distal end of the first side. The distal side of the locking sleeve has an opening. The first adjustment member extends axially within the cavity of the locking sleeve and passes through the limiting ring at the opening, so that the limiting ring cannot slide out of the first adjustment member when pulled.

[0008] According to the stent system of the present invention, when the covered stent is released into a curved blood vessel, the first side can be aligned with the slightly curved side of the blood vessel. Correspondingly, the first side of the covered stent may not be fully attached to the blood vessel wall, meaning an angle (i.e., the bird's beak phenomenon) can easily form between the first side of the covered stent and the blood vessel wall. A limiting ring is fitted onto the first adjusting member at the side opening of the locking sleeve. Thus, the limiting ring is releasably locked by the cooperation of the first adjusting member and the locking sleeve. When the covered stent is released into the blood vessel, since the limiting ring is connected to the distal end of the first side, the position of the distal end of the first side can be adjusted by pulling the limiting ring, causing the first side of the covered stent to adhere to the blood vessel wall. This reduces or eliminates the angle between the first side and the blood vessel wall, lowers the possibility of endoleak in the covered stent, and improves the safety of the covered stent application.

[0009] In addition, the support system according to the present invention may also have the following additional technical features:

[0010] In some embodiments of the invention, the distal edge of the first adjusting member extends beyond the distal edge of the opening.

[0011] In some embodiments of the present invention, the distal end of the first side includes an adjustment region, and the limiting ring is disposed at the distal end of the adjustment region, or the adjustment structure further includes a locking ring, the locking ring is disposed at the distal end of the adjustment region, and the limiting ring is connected to the locking ring, so that when the limiting ring is pulled, the force point of the covered support is located at the distal end of the adjustment region.

[0012] In some embodiments of the present invention, the adjustment structure further includes a locking ring disposed at the distal end of the adjustment region, and the adjustment structure further includes an adjustment line connected to the proximal end of the adjustment region, the limiting ring being fastened to the distal end of the adjustment line and passing through the inner ring of the locking ring axially from the proximal end to the distal end.

[0013] In some embodiments of the present invention, the covered support includes a plurality of constraint rings spaced apart along the axial direction of the adjustment region, the plurality of constraint rings being disposed between the proximal end of the adjustment line and the locking ring, and the adjustment line passing through the plurality of constraint rings in sequence.

[0014] In some embodiments of the present invention, the adjustment structure further includes a locking ring and an adjustment line. The locking ring is disposed at the distal end of the first side, and the limiting ring is fastened at the distal end of the adjustment line. The limiting ring passes through the inner ring of the locking ring axially from the distal end to the proximal end, so that the adjustment line forms a folded portion. The folded portion passes through the proximal end of the covered support, so that the limiting ring is fastened on the proximal side of the covered support.

[0015] In some embodiments of the present invention, the covered stent includes a semi-release structure, the semi-release structure including a plurality of restraint units spaced apart along the axial direction; the distal end of the first adjusting member extends beyond the distal end of the locking sleeve, the first adjusting member including a locking rod or a locking inner tube, the portion of the locking rod or the locking inner tube extending beyond the locking sleeve passing sequentially through the restraint units along the axial direction, thereby radially compressing the covered stent from its natural state to a semi-restrained state.

[0016] In some embodiments of the present invention, the distal end of the locking sleeve is located at the proximal end of the covered stent.

[0017] In some embodiments of the present invention, the restraint unit includes a beam diameter line and a locking assembly, wherein the length of the beam diameter line is less than the circumference of the covering bracket at its corresponding position in its natural state, so that when the locking rod passes through the locking assembly in sequence along the axial direction, the restraint unit can radially compress the covering bracket.

[0018] In some embodiments of the present invention, the locking ring is located on the inner or outer side of the film-covered bracket. Attached Figure Description

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0020] Figure 1 This is a schematic diagram of the structure in the prior art where the stent produces a "bird's beak" phenomenon at the aortic arch;

[0021] Figure 2 This is a schematic diagram illustrating the deployment of a covered stent into the aortic arch according to some embodiments of the present invention;

[0022] Figure 3 This is a simplified structural diagram of a support system according to some embodiments of the present invention;

[0023] Figure 4 for Figure 3 A magnified view of a portion of the image;

[0024] Figure 5 for Figure 3 The diagram shows the adjustment process of the support system.

[0025] Figure 6 This is a partially enlarged schematic diagram of the support system according to some embodiments of the present invention;

[0026] Figure 7 This is a partial structural schematic diagram of the support system according to other embodiments of the present invention;

[0027] Figure 8 for Figure 7 A magnified view of a portion of the image;

[0028] Figure 9 for Figure 7 The diagram shows the adjustment process of the support system.

[0029] Figure 10 Schematic diagrams of partial structures of the support system according to some embodiments of the present invention;

[0030] Figure 11 This is a simplified schematic diagram of a partial structure of a support system according to some embodiments of the present invention;

[0031] Figure 12 This is a simplified structural diagram of a support system according to some embodiments of the present invention;

[0032] Figure 13 This is a simplified schematic diagram of the structure of the covered stent system in a semi-restrained state according to some embodiments of the present invention;

[0033] Figure 14 for Figure 13 A magnified view of a portion of the image;

[0034] Figure 15 for Figure 14 The diagram shows the stent system in a semi-restricted state.

[0035] The attached figures are labeled as follows:

[0036] 10. Covering support; 11. First side; 111. Adjustment area; 12. Second side; 13. Partial release section; 14. Partial release structure; 141. First restraint unit; 142. Restraint unit; 1421. Beam diameter line; 1422. Locking assembly; 143. First developing element;

[0037] 20. Aortic arch; 21. Aortic arch wall;

[0038] 30. Adjustment structure; 31. First adjusting component; 311. Locking rod; 32. Second adjusting component; 321. Limiting ring; 322. Adjusting line; 323. Fold-back part; 33. Locking ring; 34. Constraint ring; 341. Limiting position; 35. Locking sleeve; 351. Opening. Detailed Implementation

[0039] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0040] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0041] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0042] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations.

[0043] Example 1

[0044] like Figure 2 and Figure 3 As shown, according to an embodiment of the present invention, this embodiment proposes a stent system including a covered stent 10 and an adjustment structure 30. The covered stent 10 includes a first side 11 and a second side 12 along the circumferential direction. The first side 11 and the second side 12 can be two radially opposite sides. In this embodiment, the first side 11 and the second side 12 can each occupy 180° of the circumference of the covered stent 10. Figure 2 As shown, the covered stent 10 may include a supporting framework and a covering, with the covering over the supporting framework. The supporting framework provides support for the covering and may consist of multiple wave-shaped coils arranged sequentially along the axial direction. The lumen of the covering forms a channel for blood flow. When the covered stent 10 is deployed to a curved blood vessel, the first side 11 may correspond to the lesser curvature of the vessel, and the second side 12 to the greater curvature. Consequently, the first side 11 of the covered stent 10 may not be completely attached to the vessel wall, meaning that an angle (i.e., the bird's beak phenomenon) may easily form between the first side 11 of the covered stent 10 and the vessel wall.

[0045] Combination Figure 3 and Figure 4 As shown, Figure 3 and Figure 4 The supporting skeleton is not shown; only the film boundary is shown. The adjustment structure 30 includes a first adjustment member 31, a locking sleeve 35, and a limiting ring 321. The limiting ring 321 is connected to the distal end of the first side 11. The side of the locking sleeve 35 has an opening 351. The first adjustment member 31 extends axially within the cavity of the locking sleeve 35 and passes through the limiting ring 321 at the opening 351, so that the limiting ring 321 cannot slide out of the first adjustment member 31 when it is pulled.

[0046] In existing technologies, if the covered stent does not fully adhere to the vessel wall after deployment, the lesser curvature of the stent cannot usually be directly adjusted. Instead, the entire delivery device must be retracted to move the proximal end of the stent. This method, on the one hand, cannot control the adjustment precision of the lesser curvature of the proximal stent; on the other hand, since the delivery device's sheath is inside the self-expanding stent and adheres to the greater curvature of the stent, directly retracting the entire delivery device may cause displacement of the greater curvature. However, in this embodiment, the limiting ring 321 is connected to the distal end of the first side 11 of the covered stent 10, and the limiting ring 321 is locked by the locking sleeve 35 and the first adjusting member 31. Thus, when the covered stent 10 is deployed into the vessel, directly pulling the limiting ring 321 can retract the distal end of the first side 11 (which corresponds to the lesser curvature of the aortic arch when deployed into the vessel) proximally, reducing or eliminating the "bird's beak" phenomenon. Figure 1 The distal end of the membrane-covered stent is adjusted as follows Figure 2In the medium state, the possibility of internal leakage of the covered stent 10 is reduced, the application safety of the covered stent 10 is improved, and the adjustment accuracy of the retraction dimension of the small bend side can be improved.

[0047] In this embodiment, "axial" generally refers to the length direction of the medical device during delivery, "radial" generally refers to the direction of the medical device perpendicular to its "axial" direction, and "circumferential" generally refers to the extension direction of the outline of the medical device's cross-section perpendicular to its "axial" direction. Based on this principle, the "axial," "radial," and "circumferential" directions of any component of the medical device are defined. In the field of interventional medical devices, for delivery devices used to implant medical devices into the human or animal body, the end closer to the operator is generally defined as the "proximal end," and the end farther from the operator is defined as the "distal end." Based on this principle, the "proximal end" and "distal end" of any component of the delivery device are defined. In this embodiment, the proximal and distal ends of the first adjusting member 31, locking sleeve 35, and covered stent 10, as well as the proximal and distal ends of the second adjusting member 32 mentioned later, are all defined in accordance with the proximal and distal ends of the delivery device. That is, the proximal and distal ends of the covered stent 10 are defined with reference to the state of the covered stent 10 being inside the conveyor, and when the covered stent 10 is located inside the conveyor to form a stent system, the end closer to the operator is the proximal end of the covered stent 10, and the end farther away from the operator is the distal end of the covered stent 10.

[0048] In one embodiment, such as Figure 3 and Figure 4 As shown, the limiting ring 321 can be directly disposed on the distal end of the first side 11 of the covered support 10, specifically by suturing it to the covered film or support frame at the distal end of the first side 11 with a suture. In other embodiments, the limiting ring 321 can also be connected to the distal end of the first side 11 via the second adjusting member 32. The opening 351 of the locking sleeve 35 can be disposed on the side of the distal end, the cavity of the locking sleeve 35 extends axially, and the opening 351 on the side communicates with the cavity of the locking sleeve 35, allowing the limiting ring 321 to be inserted into the locking sleeve 35 from the side. The first adjusting member 31 passes through the cavity of the locking sleeve 35 and extends distally beyond the opening 351, passing through the limiting ring 321 when it passes the opening. When the first adjusting member 31 passes through the limiting ring 321, the locking sleeve 35 and the limiting ring 321 can remain relatively fixed, thereby achieving the desired effect. Figure 5 As shown, by retracting the locking sleeve 35, the limiting ring 321 can be pulled back, so that the distal end of the first side 11 can be pulled by the limiting ring 321, so that the distal end of the first side 11 of the covered stent 10 fits against the blood vessel wall, thereby eliminating or reducing the "bird's beak" phenomenon.

[0049] Furthermore, continue to combine Figure 5As shown, in this embodiment, the first adjusting member 31 can be pulled back along the cavity of the locking sleeve 35 by the pulling action of the first adjusting member 31, so that it is pulled back to the proximal end of the opening 351, so that the distal end of the first adjusting member 31 is released from the limiting ring 321, so that the first adjusting member 31 and the locking sleeve 35 can be withdrawn.

[0050] This embodiment of the stent system may include a delivery device. The covered stent 10 can be implanted into a blood vessel for use via the delivery device. This embodiment mainly uses the implantation of the covered stent 10 into the aortic arch 20 as an example for illustration. Figure 2 As shown. The delivery device is used to release the covered stent 10, that is, to implant the covered stent 10 into the aortic arch 20. The delivery device includes a delivery handle, a sheath, a push rod, and a sheath core, which are sequentially connected from the outside to the inside. The distal end of the push rod does not extend beyond the distal end of the sheath core and is spaced apart from the distal end of the sheath core, so that the spaced portion together forms a loading space for the covered stent 10 within the sheath. The distal end of the delivery handle is connected to the proximal end of the sheath, and the proximal end of the sheath core passes through the delivery handle. The push rod includes an axial channel, along which the locking sleeve 35 extends. Before the covered stent 10 is released, the covered stent 10 is loaded into the loading space. By operating the handle to retract the sheath, the sheath moves axially relative to the sheath core, allowing the covered stent 10 to be released from the loading space into the aortic arch 20.

[0051] like Figure 5 As shown in Figure A, after the covered stent 10 is released into the blood vessel via the delivery device, the limiting ring 321 is sleeved on the distal end of the first adjusting member 31, and its relative axial movement is limited by the opening 351 of the locking sleeve 35. Furthermore, when the limiting ring 321 is pulled, it cannot slide out of the first adjusting member 31. Thus, by pulling the locking sleeve 35 proximally, the first side 11 of the covered stent 10 can move proximally, alleviating the bird's beak phenomenon between the covered stent 10 and the blood vessel. After adjustment, as... Figure 5 As shown in Figure B, by pulling the proximal end of the first adjusting member 31, the first adjusting member 31 is moved proximally within the cavity of the locking sleeve 35. When the distal end of the first adjusting member 31 moves to the proximal side of the opening 351, the first adjusting member 31 disengages from the limiting ring 321. At this time, as shown in Figure B, Figure 5 As shown in B to C, the locking sleeve 35 and the first adjustment member 31 can be detached together from the covered stent 10 for easy removal from the body.

[0052] In some embodiments, such as Figure 3 and Figure 4As shown, the distal edge of the first adjusting member 31 extends beyond the distal edge of the opening 351. That is, the distal edge of the first adjusting member 31 can be located at the distal end of the opening 351 of the locking sleeve 35. This limitation refers to the initial state before the first adjusting member 31 is retracted within the cavity of the locking sleeve 35. The distal edge of the first adjusting member 31 extending beyond the distal edge of the opening 351 ensures that there are no gaps between both ends of the first adjusting member 31 and the opening 351 in the axial direction. When the limiting ring 321 is pulled, i.e., when the locking sleeve 35 is retracted to adjust the position of the distal end of the first side 11 in this embodiment, the limiting ring 321 is less likely to detach from the distal edge of the first adjusting member 31, thus improving the stability of the support system.

[0053] In some embodiments, the first adjusting member 31 may include a locking rod 311, which passes through the cavity of the locking sleeve 35, with its distal end passing through the limiting ring 321. The locking rod 311 may be a flexible rod with a certain strength, specifically a nickel-titanium wire rod. The locking rod 311 has a certain strength, and when it engages with the limiting ring 321, it is less likely that the locking rod 311 and the limiting ring 321 will become entangled and knotted, thus improving the ease of release.

[0054] For ease of description, the first side 11 of the covered stent 10 is defined to have an axially extending adjustment region 111. This adjustment region 111 can be the area where the first side 11 of the covered stent 10 can be pulled under the action of the limiting ring 321. The adjustment region 111 is greater than the axial length of the area of ​​the first side 11 where a bird's beak phenomenon may occur when the covered stent 10 is released. The adjustment region 111 can be within a range of up to 100 mm extending from the farthest end of the covered stent 10 to the proximal end of the covered stent 10, specifically within a range of 35 mm to 65 mm from the farthest end of the covered stent 10.

[0055] In some embodiments, refer to Figure 3 and Figure 4As shown, the limiting ring 321 is directly disposed at the distal end of the adjustment area 111. The limiting ring 321 is fixedly connected to the covered stent 10. Thus, when the limiting ring 321 is pulled, the limiting ring 321 forms a force-bearing point for the covered stent 10, and this force-bearing point is located at the distal end of the adjustment area 111. In this embodiment, by disposing the limiting ring 321 at the distal end of the adjustment area 111, when the limiting ring 321 is pulled by retracting the locking sleeve 35, it can directly act on the first side 11 at the distal end of the adjustment area 111, thereby adjusting the first side 11 of the adjustment area 111. This allows the covered stent corresponding to the first side 11 of the adjustment area 111 to adhere to the aortic arch 20 wall on the lesser bend side of the aortic arch 20 as the locking sleeve 35 (i.e., the limiting ring 321) is retracted. Adjusting the first side 11 of the covered stent 10 by acting on the distal end of the adjustment region 111 has a better adjustment effect than acting only on the proximal end of the adjustment region 111, which is beneficial to improving the fit between the first side 11 of the covered stent 10 and the wall of the aortic arch 20.

[0056] It should be noted that the locking sleeve 35, the first adjusting member 31, and the limiting ring 321 of the support system can all be disposed on the outer side of the covered support 10. In some embodiments, such as Figure 6 As shown, the locking sleeve 35, the first adjusting member 31, and the limiting ring 321 can also be disposed on the inner side of the covered stent 10. Specifically, the supporting skeleton of the covered stent 10 can be disposed on the inner side of the covered stent, and the limiting ring 321 can be disposed on the supporting skeleton. The locking sleeve 35 disposed on the inner side will not be squeezed between the covered stent 10 and the blood vessel wall (which can be understood with reference to the aortic arch wall 21), which helps to reduce the adjustment resistance.

[0057] Example 2

[0058] This embodiment provides a stent system. The stent system in this embodiment differs from that in the first embodiment in that it further includes a locking ring 33, which is connected to the covered stent 10. A limiting ring buckle 321 is connected to the locking ring 33 to adjust the first side 11 of the covered stent 10.

[0059] In some embodiments, such as Figures 7 to 9 As shown, the adjustment structure 30 also includes a locking ring 33, which is located at the distal end of the adjustment area 111. The limiting ring 321 is connected to the locking ring 33. The locking ring 33 is fixedly connected to the distal end of the adjustment area 111 of the film-coated support 10. The connection position between the locking ring 33 and the film-coated support 10 forms the force point of the film-coated support 10 when the limiting ring 321 is pulled. This force point is located at the distal end of the adjustment area 111.

[0060] The limiting ring 321 and the locking ring 33 can be connected via a second adjusting member 32. Specifically, the second adjusting member 32 may include an adjusting line 322, with its proximal end connected to the proximal end of the adjusting region 111. The limiting ring 321 is located at the distal end of the adjusting line 322 and passes axially from the proximal end to the distal end within the locking ring 33. The adjusting line can be a single or multiple strands of soft silk thread, such as medical sutures or implantable metal threads. The limiting ring 321 can be a loop structure formed by knotting the adjusting line 322. The distal end of the adjusting line 322 can be knotted to form the limiting ring 321.

[0061] It is understood that the locking ring 33 is located at the distal end of the adjustment area 111. The first adjustment member 31 passes through the cavity of the locking sleeve 35 and extends distally beyond the opening 351. When passing through the opening, it passes through the limiting ring 321, so that the first adjustment member 31 and the limiting ring 321 are connected by the locking ring 33 at the sleeve formed by the locking sleeve 35. Thus, when the limiting ring 321 is pulled, the limiting position 341 of one force point of the covered bracket 10 is located at the locking ring 33 at the distal end of the adjustment area 111. Since the proximal end of the adjustment line 322 is connected to the proximal end of the adjustment area 111, when the limiting ring 321 is pulled, the limiting position 341 of another force point of the covered bracket 10 is located at the connection point between the proximal end of the adjustment line 322 and the covered bracket 10. In this embodiment, by placing the locking ring 33 at the distal end of the adjustment region 111, when the locking sleeve 35 is retracted to pull the limiting ring 321, it can act on the proximal and distal ends of the adjustment region 111 on the first side 11, thereby adjusting the adjustment region 111. This allows the endovascular graft corresponding to the minor bend of the adjustment region 111 to adhere to the aortic arch 20 wall at the bend of the aortic arch 20 as the locking sleeve 35 (i.e., the limiting ring 321) is retracted. Compared to the case where there is only one stress point on the endovascular graft, the endovascular graft has only one stress point. When the bird-beak phenomenon is severe, it may lead to severe stacking of the covered stent or incomplete elimination of the bird-beak. The adjustment force points of the adjustment structure provided in this embodiment are at both ends of the adjustment area, so that the covered stent stacking of the bird-beak retraction part is dispersed in the adjustment area. When adjusting the same degree of bird-beak phenomenon, it can reduce the severe stacking (high stacking protrusion) phenomenon caused by the adjustment of the covered stent 10 or reduce the incomplete elimination of the bird-beak, and reduce the possibility of thrombosis caused by severe stacking of the covered stent 10.

[0062] Further integration Figure 7 and Figure 8As shown, the covered support 10 may be provided with constraint rings 34 in the adjustment area 111, and multiple constraint rings 34 are provided between the proximal end of the adjustment line 322 and the locking ring 33. One or more constraint rings 34 may be provided. When multiple constraint rings 34 are provided, the multiple constraint rings 34 may be spaced apart along the axial direction of the adjustment area 111, and the limiting ring 321 of the adjustment line 322 may pass through all constraint rings 34 sequentially from the proximal end to the distal end along the axial direction.

[0063] The constraint ring 34 can be connected to the film on the film-coating bracket 10 or to the support frame. The structure of the constraint ring 34 and the locking ring 33 can be the same.

[0064] The distal end of the adjustment line 322 can be threaded through the constraint ring 34. The constraint ring 34 can limit and guide the adjustment line 322. When the adjustment line 322 is pulled, the constraint ring 34 can make the force direction of the adjustment area 111 adhere to the inner or outer wall of the first side 11 of the film-coated bracket 10 along the axial direction. The direction of the adjustment line 322 is more certain, and the adjustment area of ​​the first side 11 can be adjusted more specifically, which improves the release and adjustment accuracy of the film-coated bracket 10 and makes bird beak elimination more reliable.

[0065] In this embodiment, the first adjusting member is the same as in Embodiment 1, and may include a locking rod. The locking rod 3 may be a flexible rod with a certain strength, specifically a nickel-titanium wire rod. Whether the nickel-titanium wire rod is hollow or solid is not limited.

[0066] In this embodiment of the bracket system, at the opening 351, the locking rod 311 and the limiting ring 321 are fitted together to form a connection. The limiting ring 321 passes through the locking ring 33, allowing the locking ring 33 to restrict the axial movement of the connection. In this embodiment, since the limiting ring 321 passes through the opening 351 of the locking sleeve 35, when the locking rod 311 and the limiting ring 321 are fitted together, the limiting ring 321 does not disengage from the opening 351. Therefore, the limiting ring 321 remains relatively fixed to the locking sleeve 35. Thus, if... Figure 9 As shown in A, and can be combined Figure 7 By pulling the locking cannula 35 backward, the limiting ring 321 can be pulled, which in turn pulls the adjusting line 322, the locking ring 33, and the proximal connection of the adjusting line, thereby adjusting the adjustment area of ​​the first side 11 of the covered stent 10. After the first side 11 of the covered stent 10 is adjusted to fit against the vessel wall, as... Figure 9 As shown in B, and can be combined Figure 7 Pulling the locking rod 311 backward relative to the locking sleeve 35, causing the distal end of the locking rod 311 to retract through the opening 351 to the proximal side of the opening 351, allows the limiting ring 321 to disengage from the locking rod 311. Figure 9 As shown in B; at this time, as Figure 9As shown in C, by retracting the locking sleeve 35 as a whole, the locking rod 311 and the locking sleeve 35 can be kept relatively stationary in the axial direction, and the locking rod 311 and the locking sleeve 35 can be removed from the body together.

[0067] like Figure 7 As shown, in this embodiment, when adjusting the first side 11 of the covered stent 10, the proximal end of the adjustment line 322 and the fixed end of the covered stent 10 form a limiting position 341 for a force point, and the locking ring 33 forms another limiting position 341 for a force point. The stacking of the covered stent 10 can be dispersed in this adjustment area. When adjusting the same degree of bird beak phenomenon, the severe stacking phenomenon caused by the adjustment of the covered stent 10 can be reduced or the situation of incomplete bird beak elimination can be reduced, and the possibility of thrombosis caused by severe stacking of the covered stent 10 can be reduced. Furthermore, by locking the limiting ring 321 of the adjustment line 322 with the locking sleeve 35 and the locking rod 311, a closed-loop locking structure is formed, which has higher reliability and stability. At the same time, the shorter end of the adjustment line 322 can be fixed on the covered stent 10 without being removed from the body. That is to say, only the locking rod 311 and the locking sleeve 35 need to be removed from the body together, which reduces the removal time of the adjustment structure 30 and makes the operation convenient.

[0068] In some implementations, such as Figures 7 to 9 As shown, the locking rod 311, locking ring 33, locking sleeve 35, and limiting ring 321 can all be located on the outside of the covered stent 10. In this configuration, the adjustment line 322 is located on the outside of the covered stent 10, which avoids the risk of thrombosis forming within the covered stent 10. In other implementations, such as... Figure 10 As shown, the locking ring 33, locking rod 311, locking sleeve 35, and limiting ring 321 can all be located inside the covered stent 10. In this configuration, the locking sleeve 35 and locking rod 311 will not be compressed between the covered stent 10 and the blood vessel, resulting in less resistance to adjustment. Figure 11 As shown, in some implementations, the locking sleeve 35 and locking rod 311 can be disposed on the inner side of the covered stent 10, the locking ring 33 can be disposed on the outer side of the covered stent 10, the proximal end of the adjustment line 322 can be connected to the outer side of the covered stent 10, and the other end of the adjustment line 322 can be connected to the locking rod 311 after passing around the distal end of the covered stent 10. In this way, the locking sleeve 35 and locking rod 311 will not be squeezed between the covered stent 10 and the blood vessel, the adjustment resistance is smaller, and after the locking sleeve 35 and locking rod 311 are withdrawn, the proximal end of the adjustment line 322 is fixed and mainly floats on the outer side of the covered stent 10, which can reduce the risk of thrombosis caused by the adjustment line 322 floating on the inner surface of the covered stent 10.

[0069] It should also be noted that, such as Figures 7 to 11As shown, the limiting ring 321 can be located at the distal end of the locking ring 33; as Figure 12 As shown, the limiting ring 321 can also be set on the proximal side of the locking ring 33. When the limiting ring 321 is set on the proximal side of the locking ring 33, the limiting ring 321 passes through the rings of multiple constraint rings 34 and the rings of the locking ring 33 in sequence from the proximal end to the distal end along the axial direction. After that, it can be folded back from the outside of the locking ring 33 and sleeved on the locking rod 311.

[0070] Example 3

[0071] This embodiment provides a stent system, which differs from Embodiment 1 mainly in that the limiting ring 321 is located on the proximal side of the covered stent 10. Specifically, as shown... Figure 13 and Figure 14 As shown, the adjustment structure 30 also includes a locking ring 33 and an adjustment line 322. The locking ring 33 is located at the distal end of the first side 11, and the limiting ring 321 is located at the distal end of the adjustment line 322 (at this time, the proximal end of the adjustment line extends toward the operating handle of the conveyor). The limiting ring 321 passes through the inside of the locking ring 33 along the axial direction from the distal end to the proximal end, so that the adjustment line 322 forms a folded portion 323. The folded portion 323 passes through the proximal end of the film-covered bracket 10, so that the limiting ring 321 is located on the proximal side of the film-covered bracket 10.

[0072] The adjusting line 322, with one end facing away from the limiting ring 321, can be externally mounted. The adjusting line 322 wraps around the locking ring 33 to form a fold-back portion 323, allowing the pulling of the adjusting line 322 to act on the locking ring 33. For example... Figure 15 As shown, since the distal end of the adjustment line 322 is restricted from axial movement by the limiting ring 321 and the first adjustment member 31 (i.e., the locking rod 311), the locking ring 33 can be pulled by pulling the end of the adjustment line 322 located outside the body, and the first side 11 of the covered stent 10 can be bent by the locking ring 33 to fit the blood vessel wall. After the covered stent 10 is adjusted into place, the first adjustment member 31 (i.e., the locking rod 311) can be pulled back in the cavity of the locking sleeve 35 by pulling, so that the first adjustment member 31 is disengaged from the limiting ring 321. At this time, the first adjustment member 31 is released from the limiting ring 321, and the adjustment line 322 can be withdrawn from the body by pulling the end of the adjustment line 322 located outside the body. By pulling the locking sleeve 35 and keeping the locking sleeve 35 and the locking rod 311 relatively stationary, the locking sleeve 35 and the locking rod 311 can be withdrawn from the body together.

[0073] It should be noted that the end of the adjustment line 322 that is away from the limiting ring 321 can also be connected to the film-coating bracket 10. For details, please refer to the following reference. Figure 12 As shown, in this case, the adjusting line 322 may not need to be removed, and the locking sleeve 35 and locking rod 311 may be removed in accordance with the method of Embodiment 2.

[0074] Alternatively, in some embodiments, such as Figure 13 , Figure 14 and Figure 15 As shown, the covered stent 10 includes a semi-release structure 14, which includes a plurality of restraining units 142 spaced apart along the axial direction. The distal end of the first adjusting member 31 extends beyond the distal end of the locking sleeve 35. The first adjusting member 31 includes a locking rod 311 or a locking inner tube. The portion of the locking rod 311 or the locking inner tube extending beyond the locking sleeve 35 passes sequentially through the restraining units 142 along the axial direction, thereby radially compressing the covered stent 10 from its natural state to a semi-restrained state. Figures 13-14 As shown.

[0075] The covered stent 10 may have a partial release portion 13 at its distal end, which can be a portion of the distal end of the covered stent 10. A partial release structure 14 can be disposed on the partial release portion 13. When the covered stent 10 is released from the loading space of the delivery device, it is released into the blood vessel. At this time, the partial release portion 13 is in a semi-restrained state under the action of the partial release structure 14. In the semi-restrained state, since the covered stent 10 has not yet tightly adhered to the blood vessel wall, the position of the covered stent 10 can be adjusted. After the covered stent 10 is adjusted into position, the restraint of the partial release structure 14 on the partial release portion 13 can be further released, allowing the covered stent 10 to be interference-anchored within the blood vessel. By providing the partial release portion 13 and the partial release structure 14, the position adjustment of the covered stent 10 is facilitated, improving the release accuracy of the covered stent 10. After the partial release portion 13 is released, the small curved side (i.e. the first side 11) of the covered stent 10 can be further adjusted by retracting the adjustment line or locking cannula 35 to make the covered stent 10 fit against the blood vessel wall.

[0076] For ease of description, the binding unit at the nearest end of the semi-release structure 14 is defined as the first binding unit 141, as follows: Figure 14 As shown, the first restraint unit 141 is located on the distal side of the limiting ring 321.

[0077] In some implementations, a first developing element 143 can be provided between the first binding unit 141 and the limiting ring 321. The first developing element 143 can be provided on the support frame or the coating. The first developing element 143 can serve as a marker to prevent the locking lever 311 from retracting too much and disengaging from the limiting ring 321, causing the distal end of the locking lever 311 to disengage from the limiting ring 321 prematurely. This results in a situation where, after the partial release portion 13 is released, the distal end of the first side 11 of the coating support 10 cannot be further adjusted by pulling the adjustment line 322.

[0078] Optionally, in one implementation, continue to refer to Figure 13 and Figure 14As shown, the semi-release structure 14 includes a plurality of restraint units 142 spaced apart along the axial direction of the semi-release portion. Each restraint unit 142 includes a beam diameter line 1421 and a locking assembly 1422. The length of the beam diameter line 1421 is less than the circumference of the semi-release portion at its corresponding position in its naturally expanded state, so that when the locking rod 311 passes through the locking assembly 1422 sequentially along the axial direction, the restraint unit 142 can radially compress the semi-release portion to a semi-restrained state.

[0079] In one implementation, one end of the beam diameter line 1421 can be a fixed end connected to the film-coating bracket 10, and the other end of the beam diameter line 1421 is a movable end. Both the fixed end and the movable end are provided with a locking assembly 1422. The distal end of the locking rod 311 can pass through the locking assembly 1422. Through the cooperation of the locking assemblies 1422 of the fixed end and the movable end, the movable end and the fixed end of the beam diameter line 1421 are relatively fixed in the circumferential direction. This allows the beam diameter line 1421 to compress the semi-released portion 13 radially when the locking rod 311 is not disengaged from the locking assembly 1422 and the constraint ring 34, thus placing the semi-released portion 13 in a semi-restrained state. Figure 13 and Figure 14 As shown, in another implementation, the beam diameter line 1421 can also have movable ends at both ends, and each end is provided with a locking assembly 1422. The distal end of the locking rod 311 can pass through the locking assemblies 1422 at both ends of the beam diameter line 1421. Since the two ends of the beam diameter line 1421 are fixed by the locking rod 311, the beam diameter line 1421 can compress the semi-released portion in the radial direction, thereby compressing the semi-released portion radially to make it in a semi-restrained state.

[0080] During the release of the covered stent 10, when the covered stent 10 is released from the sheath, the distal half of the covered stent 10 remains in a semi-restrained state, and its expanded diameter can be approximately 40% to 80% of its fully expanded diameter; for example... Figure 15 As shown, after the coated support 10 is accurately positioned, pull the locking rod 311 to disengage it from the locking assembly. At this point, the cable diameter 1421 is released, and the partially released portion is no longer restrained by the restraint unit 142, allowing it to naturally expand and fully unfold. Pull the locking rod 311 until the partially released portion is fully unfolded. In this embodiment, the support system can simultaneously function as a bird's beak for adjusting the tension after partial release and full release of the coated support 10.

[0081] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A support system, characterized in that, The stent system includes a covered stent and an adjustment structure. The covered stent includes a first side and a second side circumferentially. The adjustment structure includes a first adjustment member, a locking sleeve, and a limiting ring. The limiting ring is connected to the distal end of the first side. The distal side of the locking sleeve has an opening. The first adjustment member extends axially within the cavity of the locking sleeve and passes through the limiting ring at the opening, so that the limiting ring cannot slip out of the first adjustment member when pulled. The limiting ring pulls the distal end of the first side, causing the distal end of the first side of the covered stent to adhere to the vessel wall.

2. The support system according to claim 1, characterized in that, The distal edge of the first adjusting member extends beyond the distal edge of the opening.

3. The support system according to claim 1, characterized in that, The distal end of the first side includes an adjustment area, and the limiting ring is located at the distal end of the adjustment area. Alternatively, the adjustment structure may also include a locking ring located at the distal end of the adjustment area. The limiting ring is connected to the locking ring so that when the limiting ring is pulled, the force point of the covered support is located at the distal end of the adjustment area.

4. The support system according to claim 3, characterized in that, The adjustment structure further includes a locking ring disposed at the distal end of the adjustment area. The adjustment structure also includes an adjustment line, the proximal end of which is connected to the proximal end of the adjustment area. The limiting ring is fastened to the distal end of the adjustment line and passes through the inner ring of the locking ring axially from the proximal end to the distal end.

5. The support system according to claim 4, characterized in that, The film-coated support includes a plurality of constraint rings spaced apart along the axial direction of the adjustment area. The plurality of constraint rings are located between the proximal end of the adjustment line and the locking ring, and the adjustment line passes through the plurality of constraint rings in sequence.

6. The support system according to claim 1, characterized in that, The adjustment structure further includes a locking ring and an adjustment line. The locking ring is located at the distal end of the first side, and the limiting ring is fastened at the distal end of the adjustment line. The limiting ring passes through the inner ring of the locking ring axially from the distal end to the proximal end, so that the adjustment line forms a folded portion. The folded portion passes through the proximal end of the covered bracket, so that the limiting ring is fastened on the proximal side of the covered bracket.

7. The support system according to claim 6, characterized in that, The covered stent includes a semi-release structure, which includes a plurality of restraint units spaced apart along the axial direction; the distal end of the first adjusting member extends beyond the distal end of the locking sleeve, and the first adjusting member includes a locking rod or a locking inner tube. The portion of the locking rod or the locking inner tube extending beyond the locking sleeve passes sequentially through the restraint units along the axial direction, thereby radially compressing the covered stent from its natural state to a semi-restrained state.

8. The support system according to claim 7, characterized in that, The distal end of the locking sleeve is located at the proximal end of the covered stent.

9. The support system according to claim 7, characterized in that, The restraint unit includes a beam diameter line and a locking assembly. The length of the beam diameter line is less than the circumference of the film-covered bracket at its corresponding position in its natural state, so that when the locking rod passes through the locking assembly in sequence along the axial direction, the restraint unit can radially compress the film-covered bracket.

10. The stent system according to any one of claims 4-9, characterized in that, The locking ring is located on the inner or outer side of the covered support.

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