Covered stent

Abstract

The covered stent comprises a plurality of stent rings distributed in the axial direction and a covering film, and the covering film comprises a first part and a second part; the stent ring comprises a constraint state and a release state, in the constraint state, the stent ring comprises a constraint release line, the constraint release line stitches the two ends, close to the first part, of the second part, so that a compression space is defined by the first part, and the stent ring is compressed and contained in the compression space in the radial direction; and in the release state, the stent ring compressed in the compression space is expanded and is attached to the second part. Interference between the windowing position and the metal stent can be avoided, and interference between the branch artery covered stent system and the metal stent of the covered stent in the aorta in the placing process is avoided; enough supporting force can be provided in the arch area, and the covered stent in the branch blood vessel is prevented from moving towards the inside of the aortic lumen while the aortic lumen is kept unobstructed.

Description

Technical Field

[0001] The invention belongs to the technical field of vascular stents, and in particular relates to a coated stent. Background Art

[0002] Aortic dissection (AD) refers to a disease in which the middle layer of the aorta is destroyed due to bleeding in the aortic wall, resulting in the separation of the vascular wall layers, and the subsequent formation of true lumens or false lumens that are interconnected or not. In most cases, aortic dissection begins with an intimal tear, and blood enters the middle layer through the intimal tear, eventually leading to aortic rupture or re-entering the true lumen through a second intimal tear. Many factors, such as hypertension, atherosclerosis, and severe trauma, may lead to the occurrence of aortic dissection.

[0003] At present, for aortic dissection involving important branch arteries, some doctors are trying to use intravascular intervention plus in situ fenestration technology to perform total arch repair of the aorta. The general surgical procedure is: first, place a covered stent in the aorta; second, perform a fenestration operation on the covered stent in the aorta at the position corresponding to the origin of the aortic branch artery; finally, through the fenestration of the covered stent in the aorta, place the covered stent in the aortic branch blood vessel to complete the total arch repair. However, this repair direction has the following problems: after the covered stent is placed in the aorta, when the covered stent is fenestrated at the position corresponding to the origin of the branch artery, the fenestration position may interfere with the metal stent in the covered stent, and the interference may cause the fenestration failure, or cause the subsequent failure of the delivery, release, or withdrawal of the covered stent system in the branch blood vessel. Summary of the invention

[0004] In view of the above shortcomings of the prior art, an object of the present invention is to provide a covered stent to solve the problem existing in the prior repair method that after the covered stent is placed in the aorta, when the window opening operation is performed on the covered stent at the corresponding position of the origin of the branch artery, the window opening position may interfere with the metal stent in the covered stent, and the interference may cause the window opening failure, or cause the failure of the delivery, release, or withdrawal of the covered stent system in the subsequent branch blood vessel.

[0005] To achieve the above-mentioned purpose and other related purposes, the present invention provides a stent graft, comprising:

[0006] A plurality of stent rings and a coating distributed along the axial direction, wherein the coating comprises a first part and a second part;

[0007] The stent ring includes a restrained state and a released state,

[0008] In the restrained state: a restraint release line is included, the restraint release line sews the second part close to the two ends of the first part, so that the first part is enclosed to form a compression space, and the stent ring is radially compressed and accommodated in the compression space;

[0009] In the released state, the stent ring compressed in the compression space expands and fits with the second portion.

[0010] In one embodiment of the present invention, in the restraint state, the restraint release line includes a plurality of sewing sleeves distributed along a first direction, the sewing sleeves pass from a first side of the second part to a second side, and are sleeved on a next sewing sleeve on the second side, and the plurality of sewing sleeves are formed by sewing together one restraint release line.

[0011] In one embodiment of the present invention, the last suture sleeve distributed along the first direction is located on the first side of the second part and is provided with a lead-out release thread head, and the binding release thread is completely removed by pulling the release thread head to release the stent ring.

[0012] In one embodiment of the present invention, a locking structure is provided on the lead-out path of the release thread head.

[0013] In one embodiment of the present invention, the single sewing sleeve is formed by passing one end of the binding release line from the first side of the second portion to the second side, and then passing from the second side to the first side again.

[0014] In one embodiment of the present invention, the first portion is fixedly connected to the support ring in the released state.

[0015] In one embodiment of the present invention, the stent ring is made of nickel-titanium alloy.

[0016] In one embodiment of the present invention, when the cross-section of the metal wire making the bracket ring is circular, the diameter of the metal wire is 0.1mm to 1mm; when the cross-section of the metal wire making the bracket ring is square, the diagonal length of the cross-section of the metal wire is 0.1mm to 1mm.

[0017] In one embodiment of the present invention, the stent ring is located inside the coating.

[0018] In one embodiment of the present invention, the restraint release line is made of nylon, polypropylene or polytetrafluoroethylene.

[0019] The present invention proposes a coated stent, in which a stent ring can be constrained in a smaller diameter state by a portion of the coating and a binding release line. In this state, there is sufficient space for reconstruction of branch arteries, that is, when the branch arteries are reconstructed, there will be no interference with the stent ring; the binding release line can be used to constrain the stent and also to release the stent. When the reconstruction of the branch artery is completed, one end of the binding release line can be pulled to complete the release of the stent ring. The released stent ring can provide sufficient supporting force, so that the branch stent is not easily displaced.

[0020] The present invention enables, after a covered stent is placed in the aorta, when a window is opened at a position corresponding to the origin of a branch artery, the covered stent of the present invention can avoid interference between the window opening position and the metal stent; when a covered stent of a branch artery is placed through the window of the covered stent in the aorta, the covered stent of the present invention can avoid interference between the covered stent system of the branch artery and the metal stent of the covered stent in the aorta during placement; and after the aortic arch is repaired, the covered stent of the present invention can provide sufficient supporting force in the arch area, thereby preventing the covered stent in the branch blood vessel from shifting into the aortic lumen while maintaining the patency of the aortic lumen. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0022] Figure 1 It is a main schematic diagram of a coated stent in a restrained state in one embodiment of the present invention.

[0023] Figure 2 It is a schematic side view of a coated stent in a restrained state according to one embodiment of the present invention.

[0024] Figure 3 FIG. 1 is a schematic diagram of a tie-release line path in one embodiment of the present invention.

[0025] Figure 4 Schematic diagram of a coated stent in a released state according to one embodiment of the present invention.

[0026] Figure 5 Schematic diagram of the fenestration position of the stent graft in the aorta and the interference with its metal stent.

[0027] Figure 6 A schematic diagram of placing a stent graft in a restrained state to a specified position.

[0028] Figure 7 Schematic diagram of the window opening on the film.

[0029] Figure 8 This is a schematic diagram after the branch reconstruction is completed.

[0030] Fig. 9 Schematic diagram after reconstruction of the aortic arch area.

[0031] Description of labels:

[0032] 100. Stent graft; 101. Stent ring; 102. Stent graft; 1021. First part; 1022. Second part; 103. Restraint release line; 1031. Suture sleeve; 1032. First end; 1. Main stent graft; 2. Branch stent graft; 3. Region; 4. Window. DETAILED DESCRIPTION

[0033] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0034] It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner. Therefore, the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0035] See also Figures 1 to 4As shown, the present invention proposes a stent to solve the problem in the existing repair method that after the covered stent is placed in the aorta, when the window opening operation is performed on the covered stent at the corresponding position of the origin of the branch artery, the window opening position may interfere with the metal stent in the covered stent, and the interference may cause the window opening failure, or cause the failure of the delivery, release, or withdrawal of the covered stent system in the subsequent branch blood vessel. Specifically, the coated stent 100 includes a plurality of stent rings 101 and a coating 102 distributed along the axial direction, the coating 102 includes a first part 1021 and a second part 1022, the stent ring 101 includes a restrained state and a released state, in the restrained state, the coated stent 100 includes a restraint release line 103, the restraint release line 103 is sutured to the two ends of the second part 1022 close to the first part 1021, so that the first part 1021 is enclosed to form a compression space, the stent ring 101 is radially compressed and accommodated in the compression space, when the restraint release line 103 is removed, the stent ring 101 is released from the restraint, thereby expanding radially to be in a released state, in the released state, the stent ring 101 compressed in the compression space expands and fits with the second part 1022.

[0036] See also Figures 1 to 4 As shown, in this embodiment, in the restrained state, the restraint release line 103 includes a plurality of sewing sleeves 1031 distributed along the first direction X, the sewing sleeve 1031 passes from the first side to the second side of the second portion 1022, and is sleeved on the next sewing sleeve 1031 on the second side. It can be understood that the plurality of sewing sleeves 1031 are formed by sewing one restraint release line 103. In this embodiment, a single sewing sleeve 1031 is formed by the first end 1032 of the restraint release line 103 passing from the first side of the second part 1022 to the second side, and then passing from the second side to the first side again. This sewing method allows the restraint release line 103 to form a double-layer structure on the second side. When sewing to form the next sewing sleeve 1031, the first end 1032 is passed from the first side of the second part 1022 to the second side again, and then passed from the second side to the first side again to form another double-layer structure. The double-layer structure passes through the double-layer structure formed on the second side by the previous sewing sleeve 1031, and so on. The double-layer structure of the third sewing sleeve passes through the double-layer structure of the second sewing sleeve to sew to form multiple sewing sleeves.

[0037] See also Figures 1 to 4As shown, in this embodiment, the last suture sleeve 1031 distributed along the first direction X is located on the first side of the second part 1022 and is provided with a lead-out release thread head, which is the first end 1032 of the above-mentioned restraint release line 103. By pulling the release thread head, the restraint release line 103 can be completely removed at one time to release the stent ring 101, making the release of the stent ring 101 very convenient. In this embodiment, a locking structure can also be provided on the lead-out path of the release thread head. Only after the locking structure is removed can the release thread head of the restraint release line 103 be pulled to complete the release of the stent ring 101, thereby preventing it from being released by mistake and ensuring its safety. In this embodiment, the restraint release line 103 is a polymer line, which can be made of medical polymer materials such as nylon, polypropylene, and polytetrafluoroethylene.

[0038] See also Figures 1 to 4 As shown, in this embodiment, the stent ring 101 is a wavy or grid-shaped closed frame, which is located on the inner side of the coating 102. The stent ring 101 can be partially attached to the inner side of the coating 102. For example, the first part 1021 is fixedly connected to the stent ring 101 in the released state to better restrain the stent ring 101 in the restrained state. In this embodiment, the coating 102 is a layer of flexible columnar film material attached to the stent ring 101 by suturing or bonding, which can be made of materials such as polyester fiber or expanded polytetrafluoroethylene. Preferably, the connection method is suturing and the material is polyester fiber.

[0039] See also Figures 1 to 4 As shown, in this embodiment, the stent ring 101 described in the above embodiment is made of metal or polymer material, preferably, nickel-titanium alloy, when the cross section of the metal wire of the stent ring is circular, the diameter of the metal wire is 0.1mm to 1mm, when the cross section of the metal wire of the stent ring is square, the diagonal length of the cross section of the metal wire is 0.1mm to 1mm. Of course, the stent ring 101 can be a cut stent, that is, the cross section of the metal wire made of laser cutting metal pipe is square.

[0040] See also Figures 1 to 4As shown, in the present embodiment, the main functions of the above-mentioned stent graft are: when the stent graft 100 is in a restrained state, it provides sufficient space for the reconstruction of the branch blood vessels, that is, when the branch blood vessels are reconstructed, it will not interfere with the stent ring 101; and when the stent graft 100 is in a released state, it can maintain the hollow cylindrical shape of the stent graft 100, and stably anchor the stent graft 100 and the stent graft in the branch blood vessel (branch artery stent graft) on the inner wall of the blood vessel, prevent the displacement of the stent graft 100 and the branch artery stent graft in the blood vessel, ensure that the blood flows smoothly in the lumen of the stent graft 100 and the branch artery stent graft, and ensure that the blood does not seep to the outside of the coating.

[0041] See also Figures 5 to 9 It should be noted that during the repair of the aorta, if there are accumulated branch vessels at the repair site, the general operation process is as follows:

[0042] Placement of a main stent graft 1 (aortic stent graft) in the aorta;

[0043] A window is opened on the membrane of the aortic stent graft, where the window is a window for connecting the aortic stent graft with the branch stent graft 2 (branch artery stent graft) in the branch artery; it is understandable that if the membrane of the aortic stent graft has a pre-set window, this step can be omitted;

[0044] A branch artery covered stent is placed in the branch vessel through the window on the aortic covered stent.

[0045] See also Figure 5 As shown, during the fenestration and branch artery stent graft placement operations, the device may interfere with the metal stent of the aortic stent graft in area 3, and the interference may cause the fenestration failure or the subsequent failure of the delivery, release, or retraction of the branch artery stent graft system.

[0046] The gripping and releasing methods of the stent graft of the present invention can avoid the interference between the instruments and the metal stent when opening the window and placing the branch artery stent graft. At the same time, after the aortic arch is repaired, the stent graft of the present invention can provide sufficient support in the arch area, thereby preventing the stent graft in the branch blood vessel from shifting into the aortic cavity, and at the same time, maintaining the natural blood flow state in the aorta and its branch blood vessels.

[0047] See also Figures 6 to 9 As shown, in the present invention, the reconstruction of the aorta with branches is simplified into the following four steps. Here, for the convenience of description, the aortic arch area is selected as the area to be reconstructed:

[0048] The stent graft 100 in a restrained state is placed at a designated position of a blood vessel by percutaneous intervention or surgical thoracotomy;

[0049] A windowing operation is performed on the position of the branch blood vessel corresponding to the coating 102 of the covered stent in the restrained state, so that the coating 102 has a window 4 corresponding to the branch blood vessel on the aortic arch; for example, a sharp needle can be used to rupture the coating, and then a balloon is used to expand the hole on the coating to complete the windowing operation; or as an option, a laser can be used to rupture the coating, and then a balloon is used to expand the hole on the coating to complete the windowing operation; a portable electrocoagulation knife can also be used to perform the windowing operation on the coating;

[0050] Perform branch vessel reconstruction operations through the opening window 4 of the stent graft 100, including delivery, release and withdrawal of the branch artery stent graft system, to complete the reconstruction of the branch vessel;

[0051] After the branch reconstruction is completed, the first end 1032 of the binding release line 103 is pulled to remove the binding release line 103 from the coated stent 100 to complete the release of the stent ring 101 .

[0052] The present invention proposes a coated stent, in which a stent ring can be constrained in a smaller diameter state by a partial coating and a binding release line. In this state, there is sufficient space for reconstruction of branch arteries, that is, when the branch arteries are reconstructed, there will be no interference with the stent ring; the binding release line can be used to constrain the stent and also to release the stent. When the reconstruction of the branch artery is completed, one end of the binding release line can be pulled to complete the release of the stent ring. The released stent ring can provide sufficient supporting force, so that the branch stent is not easily displaced.

[0053] The present invention enables, after a covered stent is placed in the aorta, when a window is opened at a position corresponding to the origin of a branch artery, the covered stent of the present invention can avoid interference between the window opening position and the metal stent; when a covered stent of a branch artery is placed through the window of the covered stent in the aorta, the covered stent of the present invention can avoid interference between the covered stent system of the branch artery and the metal stent of the covered stent in the aorta during placement; and after the aortic arch is repaired, the covered stent of the present invention can provide sufficient supporting force in the arch area, thereby preventing the covered stent in the branch blood vessel from shifting into the aortic lumen while maintaining the patency of the aortic lumen.

[0054] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope involved in the present application is not limited to the technical solution formed by a specific combination of the above-mentioned technical features, but should also cover other technical solutions formed by any combination of the above-mentioned technical features or their equivalent features without departing from the inventive concept, such as a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features with similar functions disclosed in this application.

[0055] Except for the technical features in the specification, the other technical features are known technologies to those skilled in the art. In order to highlight the innovative features of the present invention, the other technical features will not be described in detail here.

Claims

1. A stent graft, characterized in that: include: A plurality of stent rings and a coating distributed along the axial direction, wherein the coating comprises a first part and a second part; The stent ring includes a restrained state and a released state, In the restrained state: a restraint release line is included, the restraint release line sews the second part close to the two ends of the first part, so that the first part is enclosed to form a compression space, and the stent ring is radially compressed and accommodated in the compression space; In the released state, the stent ring compressed in the compression space expands and fits with the second portion.

2. The stent graft according to claim 1, characterized in that: In the restraint state, the restraint release line includes a plurality of sewing sleeves distributed along a first direction, the sewing sleeves pass from a first side of the second part to a second side, and are sleeved on a next sewing sleeve on the second side, and the plurality of sewing sleeves are formed by sewing one restraint release line.

3. The stent graft according to claim 2, characterized in that: The last suture sleeve distributed along the first direction is located at the first side of the second part and is provided with a lead-out release thread head. The release thread head is pulled to completely remove the binding release thread to release the bracket ring.

4. The stent graft according to claim 3, characterized in that: A locking structure is provided on the lead-out path of the release thread head.

5. The stent graft according to claim 2, characterized in that: The single sewing sleeve is formed by passing one end of the binding release line from the first side of the second portion to the second side, and then passing it from the second side to the first side again.

6. The stent graft according to claim 1, characterized in that: The first portion is fixedly connected to the support ring in a released state.

7. The stent graft according to claim 1, characterized in that: The support ring is made of nickel-titanium alloy.

8. The stent graft according to claim 1, characterized in that: When the cross section of the metal wire used to make the bracket ring is circular, the diameter of the metal wire is 0.1 mm to 1 mm; when the cross section of the metal wire used to make the bracket ring is square, the diagonal length of the cross section of the metal wire is 0.1 mm to 1 mm.

9. The stent graft according to claim 1, characterized in that: The stent ring is located on the inner side of the covering membrane.

10. The stent graft according to claim 1, characterized in that: The restraint release line is made of nylon, polypropylene or polytetrafluoroethylene.

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