A covered stent

Abstract

The application belongs to the technical field of medical devices, and particularly relates to a covered stent, which comprises a stent body and a covering arranged on the stent body, the stent body comprises a keel, a wave coil assembly and a sleeve joint assembly for connecting the keel and the wave coil assembly; the wave coil assembly comprises at least one curved section connected to the keel, the curved section comprises a plurality of curved wave coils arranged on the keel in sequence, and the sleeve joint assembly comprises a plurality of curved sleeves for connecting adjacent curved wave coils; and the curved section is provided with a recessed part recessed towards the inner side of the stent body. According to the covered stent, the recessed part is adapted to the branch vessels on the aortic arch, so that the vessels near the aortic arch are adapted, and the covered stent can be set to a preset curved shape according to the shape of the vessels through the curved sleeves, so as to reduce the pressure of the covered stent on the inner wall of the vessels, reduce the stimulation of the covered stent on the vessels and prevent new vessel breaks.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of medical devices, and particularly relates to a covered stent. BACKGROUND

[0002] Aortic aneurysm and aortic dissection are diseases that seriously endanger human life safety at present. If not actively treated, the aortic aneurysm and dissection will continue to enlarge, and finally rupture, causing serious complications and death. With the increasing number of patients with hypertension, hyperlipidemia and diabetes, the incidence of aortic aneurysm and aortic dissection is also significantly increasing.

[0003] Traditional open surgery for aortic aneurysm and aortic dissection has the characteristics of large trauma, high mortality, long operation time, high incidence of postoperative complications and high surgical difficulty, while endovascular treatment has the characteristics of small trauma, fewer postoperative complications, short operation time and low surgical difficulty, and gradually becomes the main way for treating aortic aneurysm and aortic dissection at present. By implanting a covered stent in the aorta, the vascular lesions are isolated outside the covered stent, and the blood flow is constrained to flow through the inside of the covered stent, thereby achieving the purpose of protecting the blood vessels.

[0004] At present, the overall structure of the aortic stent product is mostly a straight cylinder structure with a keel. However, the shape of the aorta is not a regular straight cylinder, especially the aortic arch is curved. Therefore, the covered stent implanted in the curved segment part of the aortic arch and the vicinity of the aortic arch will produce elastic straightening force and stress formed thereby after being passively bent, which is easy to cause new aortic rupture. The occurrence of new aortic rupture is the primary risk factor for aortic dissection after endovascular repair.

[0005] Therefore, there is a need for a new technical solution to solve the above problems. SUMMARY

[0006] The purpose of the present application is to at least solve the problem that the straightening force of the covered stent and the stress formed thereby are easy to cause new aortic rupture.

[0007] One aspect of the present application provides a covered stent, comprising a stent body and a covering film arranged on the stent body, wherein the stent body comprises a keel, a wave coil assembly and a sleeve joint assembly for connecting the keel and the wave coil assembly; the wave coil assembly comprises at least one curved segment connected to the keel, and the curved segment comprises a plurality of curved wave coils arranged on the keel in sequence; the sleeve joint assembly comprises a plurality of curved sleeves for connecting adjacent curved wave coils; and the curved segment is provided with a recessed portion recessed towards the inside of the stent body.

[0008] According to the covered stent in the application, the recesses are adapted to the branch vessels on the aortic arch, so as to adapt to the vessels near the aortic arch, and the covered stent can be set to a preset curved shape according to the shape of the vessels by the curved bending sleeves, so as to reduce the pressure of the covered stent on the inner wall of the vessels, reduce the stimulation of the covered stent on the vessels, and prevent new vessel breaks.

[0009] In addition, the covered stent according to the application can further have the following additional technical features:

[0010] In some embodiments of the application, the groove portion is arranged on one side close to the keel.

[0011] In some embodiments of the application, the curved wave ring comprises a high wave segment and a low wave segment connected end to end, the high wave segment is arranged on one side close to the keel, the low wave segment is arranged on one side away from the keel, and the axial height of the high wave segment is greater than the axial height of the low wave segment.

[0012] In some embodiments of the application, the stent body further comprises a main body segment arranged at the distal end of the curved segment, the main body segment is arranged in a straight cylinder shape, and the main body segment comprises a plurality of main body wave rings connected in sequence to the keel; the axial height of the high wave segment is greater than or equal to the axial height of the main body wave ring.

[0013] In some embodiments of the application, a half-release device is arranged on the stent body, the half-release device comprises a binding unit for binding the stent body and a limiting unit movably connected with the binding unit; the binding unit comprises at least two limiting rings arranged on the wave ring assembly and a binding line passing through the limiting rings, and the two ends of the binding line pass through the limiting rings and are adapted to the limiting unit.

[0014] In some embodiments of the application, the length of the binding line is less than the circumference of the cross section of the stent body, the limiting unit comprises a limiting rod, and the two ends of the binding line are provided with buckles, and the limiting rod is used to pass through the buckles at the two ends of the binding line at the same time.

[0015] In some embodiments of the application, the bending directions and / or bending amplitudes of the plurality of bending sleeves are the same or different.

[0016] In some embodiments of the application, the adjacent curved wave rings are connected by connecting rods, the curved wave rings are fixedly connected to the connecting rods by the bending sleeves, and a plurality of connecting rods are connected in sequence to form part of the keel; the curved wave rings and the connecting rods are integrally woven by weaving wires, and the adjacent curved wave rings are connected end to end by the connecting rods.

[0017] In some embodiments of the present application, the sleeve assembly further comprises a pressing tooth groove recessed towards the inside of the bending sleeve, the pressing tooth groove being used to fix the connection between the bending section and the keel, the bending sleeve comprising a first pressing surface and a second pressing surface arranged oppositely, and the pressing tooth groove being arranged on the first pressing surface and / or the second pressing surface.

[0018] In some embodiments of the present application, the number and / or shape of the pressing tooth groove arranged on the first pressing surface of the bending sleeve is different from that of the pressing tooth groove arranged on the second pressing surface.

[0019] In some embodiments of the present application, the pressing tooth groove comprises a first pressing groove arranged on the first pressing surface and a second pressing groove arranged on the second pressing surface; the number of the first pressing groove is less than that of the second pressing groove, and the first pressing groove is arranged staggeredly with the second pressing groove.

[0020] In some embodiments of the present application, the bending sleeve is bent towards the inside of the stent body; the first pressing surface is arranged towards the inside of the stent body, and the second pressing surface is arranged towards the outside of the stent body. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 FIG. 1 is a schematic diagram of the overall structure of the covered stent in Embodiment One of the present application;

[0022] Figure 2 FIG. 2 is a schematic diagram of the overall structure of the stent body in Embodiment One of the present application;

[0023] Figure 3 FIG. 3 is a schematic diagram of the structure of the bending section in Embodiment One of the present application;

[0024] Figure 4 FIG. 4 is an enlarged view of the structure at A in Embodiment One of the present application; Figure 1

[0025] Figure 5 FIG. 5 is a schematic diagram of the structure of the bending sleeve in Embodiment One of the present application;

[0026] Figure 6 FIG. 6 is a schematic diagram of the overall structure of the covered stent in Embodiment Two of the present application;

[0027] Figure 7 FIG. 7 is a schematic diagram of the structure of the connecting section in Embodiment Two of the present application;

[0028] Figure 8 FIG. 8 is a schematic diagram of the structure of the connecting sleeve in Embodiment Two of the present application;

[0029] Figure 9 ​Structure diagram of the first embodiment of the bending sleeve in the third embodiment of the present application;

[0030] Figure 10 Structure diagram of the second embodiment of the bending sleeve in the third embodiment of the present application;

[0031] Figure 11 Structure diagram of the third embodiment of the bending sleeve in the third embodiment of the present application;

[0032] Figure 12 Structure diagram of the overall structure of the covered stent in the fourth embodiment of the present application;

[0033] Figure 13 Structure diagram of the stent body in the fourth embodiment of the present application;

[0034] Figure 14 Structure diagram of another embodiment of the covered stent in the fourth embodiment of the present application;

[0035] Figure 15 Structure diagram of the covered stent after puncture in the fourth embodiment of the present application;

[0036] Figure 16 Structure diagram of the bending section in the fourth embodiment of the present application;

[0037] Figure 17 Structure diagram of the windowed section in the fourth embodiment of the present application;

[0038] Figure 18 Structure diagram of the overall structure of the covered stent in the fifth embodiment of the present application;

[0039] Figure 19 Structure diagram of the overall structure of the covered stent in the fifth embodiment of the present application from another perspective;

[0040] Figure 20 Structure diagram of the covered stent in the natural bending state in the fifth embodiment of the present application;

[0041] Figure 21 Structure diagram of the bending section in the fifth embodiment of the present application;

[0042] Figure 22 Structure diagram of the overall structure of the covered stent with the semi-release device in the fifth embodiment of the present application;

[0043] Figure 23 Structure diagram of the fifth embodiment of the present application; Figure 22 Enlarged view of B in the fifth embodiment of the present application;

[0044] Figure 24 Structure diagram of the covered stent in the semi-release state in the fifth embodiment of the present application.

[0045] The various tags in the drawings represent the following:

[0046] 10, covered stent; 100, stent body; 110, covering film; 120, braided wire; 200, keel; 210, connecting rod; 300, wave coil assembly; 310, bending section; 311, bending wave coil; 312, high wave section; 313, low wave section; 320, connecting section; 321, connecting wave coil; 3211, fixed wave form section; 3212, active wave form section; 322, supporting wave coil; 330, main body section; 331, main body wave coil; 400, sleeve assembly; 410, bending sleeve; 420, connecting sleeve; 430, pressure tooth groove; 431, first pressure groove; 432, second pressure groove; 433, inclined surface groove; 440, first pressure surface; 450, second pressure surface; 500, windowed section; 510, windowed wave coil; 520, puncture hole; 530, windowed area; 540, non-windowed area; 550, reinforcing wire; 600, recess portion; 610, recess bottom film; 620, through hole; 630, connecting tube; 640, developing ring; 650, recess support; 700, half-releasing device; 710, binding unit; 711, limiting ring; 712, binding wire; 713, buckle ring; 720, limiting unit; 721, limiting rod. DETAILED DESCRIPTION

[0047] Exemplary embodiments of the present application will be described herein below with reference to the accompanying drawings. While exemplary embodiments of the present application are illustrated, it is to be understood that the present application is not limited to the exemplary embodiments described herein, but can be implemented in various forms. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0048] It is to be understood that the terms used herein are merely for the purpose of describing particular embodiments and are not intended to be limiting. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0049] Although the terms first, second, third, and the like can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can be merely used to distinguish one element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates otherwise, terms such as "first," "second," and the like are used herein to distinguish one element from another, without necessarily implying an order or sequence.

[0050] For ease of description, spatial relative terms can be used herein to describe the relationship between one element or feature to another element or feature as shown in the drawings, such as "inner", "outer", "inside", "outside", "lower", "below", "upper", "above", etc. Such spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the drawings.

[0051] For ease of description, the following description uses the terms "distal" and "proximal", wherein "distal" refers to the end away from the heart, "proximal" refers to the end close to the heart, and the phrase "axial direction" should be understood in this patent to mean the direction in which the interventional instrument is pushed in and pushed out, and the direction perpendicular to the "axial direction" is defined as the "radial direction".

[0052] Embodiment one, the embodiment one of the present application provides a covered stent 10, as shown in Figure 1 With Figure 2 The covered stent 10 comprises a stent body 100 and a covering 110 arranged on the stent body 100, wherein the stent body 100 comprises a keel 200, a wave coil assembly 300 and a sleeve joint assembly 400, the wave coil assembly 300 is connected to the keel 200, and the sleeve joint assembly 400 is used to connect and fix the wave coil assembly 300 and the keel 200. The wave coil assembly 300 comprises at least one curved segment 310, which is used to adapt to the curved part of the blood vessel after the covered stent 10 is implanted in the blood vessel, especially the position with large curvature in the aortic arch.

[0053] In this embodiment, the wave coil assembly 300 comprises one curved segment 310, and in other embodiments, the wave coil assembly 300 can also be provided with multiple curved segments 310 according to actual needs, and the shapes of the multiple curved segments 310 can be the same or different to adapt to the shape of different blood vessel lumens.

[0054] The curved segment 310 comprises a plurality of curved wave coils 311, and the plurality of curved wave coils 311 are sequentially connected and fixed on the keel 200. The sleeve joint assembly 400 comprises a bending sleeve 410 for fixing the curved wave coil 311 and the keel 200, and the bending sleeve 410 is curved, so that the bending sleeve 410 drives the keel 200 and the curved wave coil 311 to bend to one side to make the whole curved segment 310 curved to adapt to the curved part of the blood vessel.

[0055] As Figure 3As shown, the embodiment is provided with the bending sleeve 410 in a curved shape on the bending section 310, so as to drive the whole bending section 310 to be in a curved shape. When the covered stent 10 is prepared, the covered stent 10 can be pre-set to be in a curved shape according to the shape of the blood vessel, so as to adapt to the aortic blood vessel. Compared with the traditional straight cylinder covered stent 10, the pre-bent covered stent 10 can better adapt to the shape of the blood vessel, reduce the pressure caused by the resilience of the covered stent 10 on the inner wall of the blood vessel, reduce the stimulation of the covered stent 10 on the blood vessel, and prevent the blood vessel from being newly broken.

[0056] The bending direction and / or the bending amplitude of each bending sleeve 410 can be the same or different. The greater the bending amplitude of the bending sleeve 410, the greater the included angle between the tangents at the two ends of the bending sleeve 410. In this embodiment, the bending sleeve 410 is bent in an arc shape, so that the bending amplitude of the bending sleeve 410 is the bending curvature of the bending sleeve 410. In actual clinical practice, the shapes of blood vessels of different patients are different, especially after the occurrence of aortic dissection, the shape of the blood vessel usually changes. Since the covered stent 10 needs to be placed in the blood vessel for a long time, if the shape of the stent body 100 is too different from the blood vessel, the stent body 100 will long-term press the inner wall of the blood vessel, causing discomfort to the patient, and even causing the blood vessel structure to change or the blood vessel to be newly broken due to blood vessel fatigue. Therefore, a general specification vascular stent cannot meet the needs of all patients, and a covered stent 10 of different shape needs to be selected according to the shape of the blood vessel of different patients to adapt to blood vessels with different bending degrees and different shapes.

[0057] Through the technical solution of the present application, the bending direction and bending amplitude of different bending sleeves 410 can be set to be different, the shape of the bending section 310 can be flexibly set to adapt to blood vessels with different shapes, and doctors can select covered stents 10 of different shapes according to the shape of the diseased blood vessel of the patient. Moreover, a corresponding covered stent 10 can be customized according to the special blood vessel shape of the patient, thereby reducing the pressure of the stent body 100 on the inner wall of the blood vessel, so that the covered stent 10 does not newly break the aorta due to the stimulation of the stent body 100 under the condition of long-term placement in the blood vessel, effectively reducing the risk after endovascular repair of aortic dissection.

[0058] In this embodiment, as shown in Figure 3 The adjacent bending coils 311 are connected by the connecting rod 210, which can be integrally woven with the bending coil 311 or welded between the adjacent two bending coils 311 to connect the bending coil 311.

[0059] The bending wave ring 311 is fixedly connected to the connecting rod 210 through the bending sleeve 410, that is, the connecting rod 210 and a part of the bending wave ring 311 are fixedly sleeved through the bending sleeve 410, so that the connection between the bending wave ring 311 and the connecting rod 210 is more firm and stable.

[0060] In the embodiment, the keel 200 is designed in a segmented manner, and the plurality of connecting rods 210 are sequentially connected to form a part of the keel 200, that is, the keel 200 is formed by sequentially connecting the plurality of connecting rods 210, and the connecting rod 210 is integrally woven with the bending wave ring 311. By adopting the above structure, the keel 200 can be formed at the same radial height as the bending wave ring 311 during weaving, and the keel 200 will not protrude relative to the bending section 310, so that the pressure of the keel 200 on the inner wall of the blood vessel is smaller than that of the protruding keel 200, further reducing the stimulation of the covered stent 10 on the inner wall of the blood vessel.

[0061] In other embodiments, as shown in Figure 2 , the keel 200 can also be designed in an integrated manner, that is, after the bending wave ring 311 is woven into shape, all the bending wave rings 311 are sequentially fixed by a strip-shaped keel 200. The keel 200 designed in an integrated manner has higher strength and better flexibility, and has simple manufacturing process and lower cost.

[0062] In the embodiment, the wave ring assembly 300 is formed by weaving the weaving wire 120, and the weaving wire 120 is a nickel-titanium wire or other metal wire with shape memory. The bending wave ring 311 and the connecting rod 210 are integrally woven by the weaving wire 120, and the adjacent bending wave rings 311 are connected end to end with the connecting rod 210 arranged therebetween. That is, the bending section 310 is integrally woven by the bending wave rings 311 and the connecting rods 210 connected end to end in sequence.

[0063] During the weaving process of the wave ring assembly 300, the sleeving assembly 400 is first sleeved on the weaving wire 120, and then is woven into shape. The sleeving assembly 400 can be bent and shaped before or after sleeving the weaving wire 120. In order to facilitate the overall weaving of the stent body 100, the sleeving assembly 400 is shaped after being sleeved on the weaving wire 120 in the embodiment.

[0064] As shown in Figure 4 , the sleeving assembly 400 further comprises a pressing tooth groove 430, which is recessed towards the inside of the bending sleeve 410 and tightly abuts on the weaving wire 120 of the wave ring assembly 300 and the keel 200, so as to connect and fix the wave ring assembly 300 and the keel 200.

[0065] As shown in Figure 5As shown, the sleeve joint assembly 400 comprises two opposite first pressing surfaces 440 and second pressing surfaces 450, and at least one of the pressing surfaces is provided with a pressing tooth groove 430. That is, the first pressing surface 440 and the second pressing surface 450 are both provided with the pressing tooth groove 430, or one of the first pressing surface 440 and the second pressing surface 450 is provided with the pressing tooth groove 430.

[0066] For the mode that the pressing tooth groove 430 is provided on only the first pressing surface 440 or the second pressing surface 450, the purpose of pressing and fixing the wave coil assembly 300 and the keel 200 through the pressing tooth groove 430 can be achieved, and the bending sleeve 410 is bent towards the side with the pressing tooth groove 430.

[0067] When the first pressing surface 440 and the second pressing surface 450 are both provided with the pressing tooth groove 430, because both sides of the bending sleeve 410 have the pressing tooth groove 430, the fixing of the bending sleeve 410 to the wave coil assembly 300 and the keel 200 is more firm.

[0068] In the embodiment, the shape of the bending sleeve 410 can be controlled by setting the number and position of the pressing tooth groove 430 on the bending sleeve 410. Specifically, the number of the pressing tooth groove 430 provided on the first pressing surface 440 of the sleeve joint assembly 400 is the same as the number of the pressing tooth groove 430 provided on the second pressing surface, or the number of the pressing tooth groove 430 provided on the first pressing surface 440 of the sleeve joint assembly 400 is different from the number of the pressing tooth groove 430 provided on the second pressing surface.

[0069] Specifically, the first pressing surface 440 of the bending sleeve 410 is provided with a first pressing groove 431, and the second pressing surface 450 of the bending sleeve 410 is provided with a second pressing groove 432. In the embodiment, the first pressing groove 431 and the second pressing groove 432 are arranged in a staggered manner, and the number of the first pressing groove 431 is less than the number of the second pressing groove 432.

[0070] Because the first pressing groove 431 and the second pressing groove 432 are arranged in a staggered manner, and the number of the first pressing groove 431 is less than the number of the second pressing groove 432, after the tooth pressing is performed, the bending sleeve 410 will be bent towards the first pressing surface 440 with fewer pressing tooth grooves 430, forming a curved bending sleeve 410.

[0071] The bending sleeve 410 of the sleeve joint assembly 400 in the embodiment is a steel sleeve or other metal material with good plastic deformation performance. Because the bending sleeve 410 has good plastic deformation performance, it has good deformation ability and stability after being pressed and formed. Specifically, the bending sleeve 410 is formed by cutting a stainless steel pipe.

[0072] The second pressure groove 432 facing the blood vessel increases the surface roughness of the bending sleeve 410, increases the friction between the covered stent 10 and the inner wall of the blood vessel as a whole, so that the covered stent 10 after being implanted in the blood vessel is not easy to displace. In addition, since the second pressure groove 432 is recessed towards the inside of the bending sleeve 410, and the bending sleeve 410 is arranged in a curved manner, the side surface of the bending sleeve 410 can better fit the inner wall of the curved blood vessel, thereby accelerating the speed of endothelial cell adhesion and further avoiding displacement of the covered stent 10 under the scouring of blood. The axial width of the wave coil assembly 300 is 1.2 to 2 times the length of the sleeve assembly 400. That is, the axial width of the wave coil assembly 300 is greater than the length of the sleeve assembly 400, preferably 1.5 times.

[0073] In the embodiment, the number of the first pressure grooves 431 of the bending sleeve 410 is 4, and the number of the second pressure grooves 432 is 5. The plurality of second pressure grooves 432 are uniformly arranged on the second pressing surface 450. The first pressure grooves 431 are arranged in the middle of the first pressing surface 440, and the first pressure grooves 431 are arranged in a staggered manner with the second pressure grooves 432. Specifically, the width of the first pressure grooves 431 is equal to the width of the second pressure grooves 432, and the ratio of the width of the first pressure grooves 431 to the width of the second pressure grooves 432 to the length of the sleeve assembly 400 is 5%-15%, preferably 8%. Therefore, the pressure tooth groove 430 will not affect the continuity of the end surface of the sleeve assembly 400 due to the too small width, nor will it cause difficulty in bending and forming due to the too large width.

[0074] In other embodiments, the number of the first pressure grooves 431 and the second pressure grooves 432 can also be more or less. When the number of the first pressure grooves 431 and the second pressure grooves 432 arranged on the bending sleeve 410 is more, for example, the number of the first pressure grooves 431 is 6, and the number of the second pressure grooves 432 is 7, the end surface of the bending sleeve 410 is smoother as a whole, but the bending amplitude is smaller. When the number of the first pressure grooves 431 and the second pressure grooves 432 arranged on the bending sleeve 410 is less, for example, the number of the first pressure grooves 431 is 2, and the number of the second pressure grooves 432 is 3, the creases at the bending part on the end surface of the bending sleeve 410 are larger, but the bending amplitude is larger.

[0075] In the embodiment, the bending sleeve 410 is bent towards the inside of the stent body 100. The first pressing surface 440 is arranged towards the inside of the stent body 100, the second pressing surface 450 is arranged towards the outside of the stent body 100, and the number of the first pressure grooves 431 on the first pressing surface 440 is less than the number of the second pressure grooves 432 on the second pressing surface 450. The bending section 310 arranged in the above manner is bent towards the direction away from the keel 200, so as to adapt to the shape of the blood vessel at the aortic arch, for example.

[0076] In other embodiments, the angle and degree of bending of the bending sleeve 410 can also be adjusted to adapt to other blood vessels with curved portions, such as S-shaped or other irregular shapes.

[0077] It should be noted that the above examples of the present embodiment are only for the convenience of technicians to understand and do not limit the present application.

[0078] Further, as Figure 2 As shown in Figure 3 The bending wave ring 311 includes a high wave band 312 and a low wave band 313 connected end to end, the high wave band 312 is located on the side close to the keel 200, and the low wave band 313 is located on the side away from the keel 200, and the axial height of the high wave band 312 is greater than that of the low wave band 313.

[0079] Specifically, when the covered stent 10 is implanted at the position of the aortic arch, the covered stent 10 is arranged in a curved shape as a whole, and generally, the side of the covered stent 10 facing the branch vessels of the aortic arch is defined as the large bending side of the covered stent 10, and the side of the covered stent 10 away from the branch vessels of the aortic arch is defined as the small bending side of the covered stent 10. In the present application, the high wave band 312 and the keel 200 are arranged on the large bending side of the covered stent 10, and the low wave band 313 is arranged on the small bending side of the covered stent 10.

[0080] Since the wave band corresponding to the small bending side is the low wave band 313, there is a larger displacement allowance between adjacent wave rings, and when the covered stent 10 is implanted in the blood vessel and arranged in a curved shape, the small bending side has better compliance.

[0081] In summary, through the above technical solutions of the present application, the covered stent can be arranged in a preset curved shape according to the shape of the blood vessel, thereby adapting to the aortic blood vessel, reducing the pressure of the covered stent on the inner wall of the blood vessel, reducing the stimulation of the covered stent on the blood vessel, and preventing new breaks in the blood vessel.

[0082] Embodiment two, the present application provides a covered stent 10, as shown in Figure 6 The same as embodiment one is not repeated, and the difference between embodiment two and embodiment one is that the stent body 100 further includes a connecting segment 320 arranged at the proximal end of the bending segment 310 and a main body segment 330 arranged at the distal end of the bending segment 310. Specifically, the main body segment 330 is arranged in a straight cylinder shape as a whole. The connecting segment 320 includes a connecting wave ring 321 and a supporting wave ring 322, the connecting wave ring 321 is used to connect the delivery device release device, and the supporting wave ring 322 is used to support the proximal edge of the covering film 110.

[0083] The stent body 100 of the embodiment not only includes the curved segment 310 in a curved shape, but also includes the main body segment 330 in a straight cylinder shape, which is arranged at the distal end of the curved segment 310. In other embodiments, the main body segment 330 in a straight cylinder shape can also be arranged at the proximal end of the curved segment 310, or the proximal end and the distal end of the curved segment 310 are both provided with the main body segment 330, which is selected according to the shape of the blood vessel of the patient, so as to adapt to the needs of different patients.

[0084] As shown in Figure 7 The support coil 322 is arranged between the covering film 110 and the connecting coil 321, and is arranged on the inner side of the covering film 110 and fixed on the covering film 110 by suturing, so as to enhance the support strength of the proximal end of the covering film 110 and prevent internal leakage.

[0085] The wire diameter of the support coil 322 is smaller than that of the connecting coil 321. After the covering stent 10 is implanted into the blood vessel, the support coil 322 supports the covering film 110 to make the covering film 110 adhere to the inner wall of the blood vessel, so that the radial support force of the support coil 322 directly affects the pressure of the covering stent 10 on the inner wall of the blood vessel.

[0086] In the embodiment, the wire diameter of the support coil 322 is set to be smaller than that of the connecting coil 321, so as to reduce the radial support force of the support coil 322, make the contact surface of the support coil 322 with the inner wall of the blood vessel softer, and stimulate the inner wall of the blood vessel less.

[0087] Further, in the embodiment, the wave number of the support coil 322 is set to be greater than that of the connecting coil 321. Since the support coil 322 is arranged between the covering film 110 and the connecting coil 321, and the radial support force of the connecting coil 321 is greater than that of the support coil 322, after the covering stent 10 is completely released, the connecting coil 321 supports the support coil 322 from the inner side. The support coil 322 can disperse the radial support force provided by the connecting coil 321, so that the pressure on the inner wall of the blood vessel is more uniform.

[0088] The connecting coil 321 is partially connected with the covering film 110. Specifically, the proximal end of the connecting coil 321 is retracted into the inner side of the covering film 110, and the connecting coil 321 includes a plurality of fixed wave segments 3211 fixedly connected with the covering film 110 and at least one active wave segment 3212 movably connected with the covering film 110.

[0089] In the embodiment, the connecting coil 321 includes at least three active wave segments 3212 movably connected with the covering film 110, and the at least three active wave segments 3212 are uniformly arranged along the circumferential direction of the covering film 110. The three active wave segments 3212 are used to connect the rear release device of the delivery device and are released after the covering stent 10 is positioned.

[0090] Before the rear release device of the conveyor releases the connecting coil 321, the movable waveform segment 3212 is restrained by the rear release device and thus restrained at the middle position of the support body 100. Since the movable waveform segment 3212 is movably connected to the film 110, the film 110 is displaced towards the inward direction of the film support 10 under the pull of the movable waveform segment 3212. The fixed waveform segment 3211 is fixedly connected to the film 110, and under the action of its own elastic force, the fixed waveform segment 3211 generates an outward radial supporting force on the film 110, thereby expanding the film 110 body.

[0091] Therefore, before the post-release device releases the connecting coil 321, the fixed waveform segment 3211 expands the covering 110 outward, while the movable waveform segment 3212 pulls the covering 110 inward, causing the front end of the covered stent 10 to be in a semi-released state. In the semi-released state, the covered stent 10 is partially deployed, thus the instantaneous force on the vascular wall is small upon full release, protecting the patient's blood vessels and preventing vascular spasm or even new vascular rupture.

[0092] Furthermore, the main body segment 330 includes a plurality of main body wave coils 331 connected sequentially to the keel 200, and the socket assembly 400 also includes a connecting sleeve 420 for connecting adjacent main body wave coils 331.

[0093] like Figure 8 As shown, the connecting sleeve 420 also includes a first pressing surface 440 and a second pressing surface 450. A first pressing groove 431 is provided on the first pressing surface 440, and a second pressing groove 432 is provided on the second pressing surface 450. The connecting sleeve 420 differs from the bending sleeve 410 in that the connecting sleeve 420 has the same number of first pressing grooves 431 and second pressing grooves 432, and the first pressing grooves 431 and second pressing grooves 432 are arranged opposite to each other. After being formed by tooth pressing, the connecting sleeve 420 is generally flat and cylindrical. Therefore, the main body section 330 is also generally cylindrical.

[0094] In this embodiment, the main body coil 331 located at the distal end of the stent body 100 has a smaller radial dimension than the main body coil 331 located at the proximal end of the stent body 100. This allows for better adaptation to the vascular diameter of the aortic arch or other vascular locations.

[0095] In other embodiments, the different main wave loops 331 can also be configured to have the same size, or the main wave loop 331 located at the far end of the support body 100 can have a larger radial dimension than the main wave loop 331 located at the near end of the support body 100. The specific selection is based on actual needs.

[0096] In summary, the stent body 100 of this embodiment includes not only the curved section 310 but also the main body section 330. Since the main body section 330 is cylindrical, the length and number of the curved section 310 and the main support section can be matched to make it more adaptable to patients with different blood vessel shapes through flexible configuration, thereby making the covered stent 10 more adaptable and reducing the pressure of the covered stent 10 on the inner wall of the patient's blood vessel.

[0097] Embodiment 3: Embodiment 3 of this application provides a covered stent 10, such as... Figure 9 to Figure 11 As shown, the similarities between Embodiment 3 and Embodiment 1 will not be repeated. The difference between Embodiment 3 and Embodiment 1 is that the number of pressure grooves 430 on the first pressing surface 440 of the sleeve assembly 400 is the same as the number of pressure grooves 430 on the second pressing surface 450.

[0098] In this embodiment, the bending sleeve 410 can be bent toward the inside of the stent body 100 or toward the outside of the stent body 100, so that the formed covered stent 10 can be adapted to the shape of the patient's blood vessels, and the specific setting is based on the shape of the patient's blood vessels.

[0099] Furthermore, the number of first pressure grooves 431 on the bending sleeve 410 is the same as the number of second pressure grooves 432, but their shapes are different.

[0100] like Figure 9 As shown, when the same number of first pressure grooves 431 and second pressure grooves 432 are provided on the bending sleeve 410, in order for the bending sleeve 410 to bend according to the preset bending degree, the groove depth of the first pressure groove 431 on the bending sleeve 410 is different from the groove depth of the second pressure groove 432. The groove depth of the first pressure groove 431 is greater than the groove depth of the second pressure groove 432. The bending sleeve 410 bends toward the side with a larger groove depth of the pressure groove 430, that is, it bends toward the direction of the first pressure groove 431.

[0101] In other implementations, such as Figure 10 As shown, the tooth height of the first pressing groove 431 on the bending sleeve 410 is different from the groove width of the second pressing groove 432. The groove width of the first pressing groove 431 is smaller than the groove width of the second pressing groove 432. The bending sleeve 410 bends toward the side with the smaller groove width of the pressing groove 430, that is, it bends toward the direction of the first pressing groove 431.

[0102] In other implementations, such as Figure 11 As shown, the pressure grooves 430 at both ends of the bending sleeve 410 are inclined grooves 433, and the inclination of the inclined grooves 433 is set according to the actual bending degree required by the bending sleeve 410.

[0103] It should be noted that the shape of the bending sleeve 410 described above is only an example and does not constitute a limitation, and any bending sleeve 410 obtained by adjusting the shape, number and position of the pressure tooth groove 430 to be curved is within the protection scope of the present application.

[0104] In embodiment four, the stent graft 10 is provided, as shown in Figure 12 to Figure 13 The same as embodiment one is not repeated, and the difference between embodiment four and embodiment one is that the stent body 100 comprises a connecting segment 320, a fenestrated segment 500 and a curved segment 310. The connecting segment 320 and the curved segment 310 are respectively arranged at the proximal end and the distal end of the fenestrated segment 500, and the curved segment 310 is used to adapt to the position with a larger bending degree near the aortic arch after the stent graft 10 is implanted into the blood vessel.

[0105] The stent graft 10 of the present embodiment is used for treating blood vessel diseases across the aortic arch and near the aortic arch. After the stent graft 10 is implanted into the blood vessel, the connecting segment 320, the fenestrated segment 500 and the curved segment 310 are respectively located at the ascending aorta, the aortic arch and the descending aorta, so that the stent graft 10 can be used to isolate the blood vessel diseases across the aorta, such as aortic aneurysm, aortic dissection, etc.

[0106] In other embodiments, as shown in Figure 14 The connecting segment 320 and the fenestrated segment 500 can also be respectively arranged at the proximal end and the distal end of the curved segment 310, so that the curved segment 310 can isolate the blood vessel diseases at the ascending aorta and better cope with the blood vessel diseases mainly located at the ascending aorta.

[0107] The fenestrated segment 500 comprises a plurality of fenestrated windings 510, which are arranged at intervals and connected by the graft 110. The distance between adjacent fenestrated windings 510 is greater than the distance between adjacent curved windings 311, and a gap for puncturing the graft 110 to form a window is reserved between adjacent fenestrated windings 510. In combination with Figure 15 As shown, the fenestrated segment 500 forms a puncture hole 520 after puncturing the graft 110 to form a window, and the puncture hole 520 is used for implanting a branch stent (not shown in the figure), which corresponds to the branch blood vessels on the aortic arch. On the other hand, since the fenestrated segment 500 is arranged at the aortic arch, the fenestrated windings 510 arranged at intervals are connected by the graft 110, which can ensure the flexibility of the fenestrated segment 500 and reduce the stimulation of the stent body 100 to the inner wall of the blood vessel.

[0108] In the present embodiment, the fenestrated segment 500 comprises at least four fenestrated windings 510. When puncturing the window, a puncture device respectively punctures between adjacent fenestrated segment windings to form three puncture holes 520, which are used to adapt to three branch blood vessels corresponding to the aortic arch.

[0109] Since the covered stent 10 is placed in the blood vessel, it is required to cover the lesion site such as aortic dissection. When the blood vessel lesion is located at the aortic arch or the curved blood vessel site across the aortic arch, the straight-tube covered stent 10 will generate elastic straightening force and stress formed thereby after being passively bent, which is likely to cause a new aortic rupture. In addition, in order to ensure that the covered stent 10 can completely cover the blood vessel lesion site, the keel 200 needs to be provided to prevent the stent from shortening, so as to avoid the stent from failing to cover the lesion site due to shortening.

[0110] The curved section 310 includes a plurality of curved windings 311 and the keel 200, the plurality of curved windings 311 are sequentially connected and fixed on the keel 200, the keel 200 between adjacent curved windings 311 is sleeved with a bending sleeve 410, and the bending sleeve 410 is curved, so that the keel 200 is bent with the bending sleeve 410, driving the curved section 310 to bend, thereby adapting to the curved site in the blood vessel.

[0111] The embodiment bends the curved section 310 on the stent body 100, thereby conforming to the shape of the blood vessel and reducing the damage to the blood vessel caused by the straightening force of the stent. In addition, the extrusion force between the outer side of the stent body 100 and the blood vessel is reduced, preventing the blood vessel from changing in structure or rupturing due to fatigue.

[0112] In combination Figure 15 As shown in the figure, the windowed winding 510 is formed by weaving the weaving wire 120, the weaving wire 120 is connected at both ends, and the connection of the weaving wire 120 is fixedly connected by the connecting sleeve 420.

[0113] Among them, as Figure 16 shown, the keel 200 of the curved winding 311 is correspondingly arranged at the large bending side of the covered stent 10, the curved winding 311 includes a high wave section 312 and a low wave section 313 connected at both ends, the high wave section 312 is located at one side close to the keel 200, and the low wave section 313 is located at the other side away from the keel 200, i.e. the low wave section 313 is correspondingly arranged at the small bending side of the covered stent 10. The axial height of the high wave section 312 is greater than the axial height of the low wave section 313, and the axial height of the windowed winding 510 is less than or equal to the axial height of the low wave section 313.

[0114] The present application sets the low wave segment 313 on the small bending side, so that there is a larger displacement allowance between adjacent bending wave rings 311, and the small bending side has better compliance when the covered stent 10 is implanted in the blood vessel and arranged in a curved shape. And since the curvature of the aortic arch is greater than that of the ascending aorta and the descending aorta, when the axial height of the fenestrated wave ring 510 is set to be less than or equal to the axial height of the low wave segment 313, the adjacent wave rings can be prevented from interfering and causing bending limitation, and the fenestrated segment 500 can be bent to a greater extent to better fit the inner wall of the blood vessel at the aortic arch.

[0115] In addition, the axial height of the fenestrated wave ring 510 is less than or equal to the axial height of the low wave segment 313, so that the gap between adjacent fenestrated wave rings 510 is larger, which can reserve a larger position for the puncture device, and facilitate the doctor to adjust the puncture position during the operation; at the same time, the release accuracy of the covered stent 10 can be reduced, thereby reducing the difficulty of the operation.

[0116] As shown in Figure 17 The fenestrated wave ring 510 includes a fenestrated area 530 for puncture fenestration and a non-fenestrated area 540. The fenestrated area 530 is arranged on the large bending side of the covered stent 10, and when implanted, the fenestrated area 530 is arranged at the branch blood vessel opening of the aortic arch. The covered membrane 110 arranged in the non-fenestrated area 540 is provided with a reinforcing wire 550, which is arranged in a ring around the radial direction of the covered membrane 110. In this embodiment, the covered membrane 110 is provided with a plurality of reinforcing wires 550, and the plurality of reinforcing wires 550 are arranged axially.

[0117] Since the bending segment 310 is bent under the action of the bending sleeve 410, the stress on the bending segment 310 increases when the covered stent 10 is loaded into the sheath, making it difficult to load the sheath. The friction between the covered stent 10 with the bending segment 310 and the sheath is greater, so that the covered stent 10 is easily displaced when released. The present application provides a plurality of reinforcing wires 550 on the covered membrane 110, which balances the stress on the bending segment 310 and other non-bending segments of the covered stent 10, making the assembly and release of the covered stent 10 more stable and smooth.

[0118] Furthermore, because the covered stent 10 has a bending sleeve 410, the endothelial adhesion of the covered stent 10 with the bending sleeve 410 is faster than that of a traditional stent. However, the bending sleeve 410 is located on one side of the keel 200. On the other side of the covered stent 10 where the keel 200 is not located, especially in the vascular area covered by the non-fenestrated area 540, the anchoring force between the covered stent 10 and the blood vessel is relatively weak. After the covered stent 10 has been placed in the blood vessel for a long time, there is a risk of displacement, shortening, or other adverse events in the non-fenestrated area 540. This application adds multiple axially spaced reinforcing wires 550 within the non-fenestrated area 540, which can increase the overall support strength of the non-fenestrated area 540 and the fenestrated area 530 after puncture, and prevent displacement, shortening, or even leakage of some segments of the covered stent 10.

[0119] Since the strength of the endovascular graft 110 is affected after fenestration, for vascular lesions spanning the aortic arch and near the aortic arch, it is necessary to consider both the blood flow of the branches above the aortic arch and the supporting strength of the endovascular graft 10. Therefore, in this embodiment, reinforcing wires 550 are provided on the endovascular graft 110 in the non-fenestration area 540 to increase the overall strength of the endovascular graft 110 after fenestration, preventing the endovascular graft 110 from tearing due to insufficient strength under long-term blood flow after puncture, and ensuring the strength of the endovascular graft 110 in the fenestration segment 500 after long-term implantation of the endovascular graft 10. In this embodiment, the bending direction and / or bending amplitude of each bending sleeve 410 can be the same or different. Since the vascular shapes of different patients are different, especially when the vascular lesion is located near the aortic arch, the vessels near the aortic arch are usually deformed due to the lesion. The above-described technical solution of this application allows for the individual setting of the shape of each bending sleeve 410, so that after the stent body 100 is formed, it adapts to the shape of the patient's vascular lumen, further reducing the stimulation of the stent body 100 on the blood vessel and reducing the probability of secondary damage to the patient's blood vessel.

[0120] like Figure 12 As shown, the connecting section 320 includes a connecting wave ring 321 and a supporting wave ring 322. The connecting wave ring 321 is a bare wave ring. The distal end of the connecting wave ring 321 is connected to the proximal end of the covering film 110. The proximal end of the connecting wave ring 321 is used to connect the delivery device after the conveyor. The supporting wave ring 322 is used to support the proximal edge of the covering film 110.

[0121] In this embodiment, the stent body 100 is provided with a fenestrated section 500 and a curved section 310. A puncture cover 110 position is reserved on the fenestrated section 500, and an implantation position for the branch stent is reserved. By using the branch stent to correspond to the branch vessels on the aortic arch, the blood flow of the branch vessels on the aortic arch is not obstructed after the covered stent 10 is implanted into the vessel, thereby adapting to vascular lesions across and near the aortic arch.

[0122] And the bending section 310 can set the covered stent 10 to a preset bending shape according to the shape of the blood vessel, so as to adapt to the blood vessel near the aortic arch, reduce the pressure of the covered stent 10 on the inner wall of the blood vessel, reduce the stimulation of the covered stent 10 on the blood vessel, and prevent new blood vessel rupture.

[0123] Embodiment five, the embodiment five of the present application provides a covered stent 10, as Figure 18 to Figure 19 As shown in the same embodiment five as embodiment one, the difference between embodiment five and embodiment one is that the bending section 310 is provided with a groove part 600, and the groove part 600 is recessed towards the inner side of the stent body 100. The covered stent 10 of the present embodiment is used for the treatment of blood vessels around the aortic arch, and the groove part 600 is correspondingly arranged at the aortic arch after the covered stent 10 is implanted into the blood vessel. The groove part 600 is opened on the cover 110, and the groove part 600 forms a substantially rectangular shape on the cover 110, that is, when the cover 110 is unfolded, a rectangular window is formed.

[0124] The groove part 600 includes a groove bottom film 610 connected with the cover 110, a through hole 620 arranged between the groove bottom film 610 and the cover 110, and a connecting pipe 630 communicated with the through hole 620. When the bending section 310 is implanted into the blood vessel, the groove part 600 is correspondingly arranged at the aortic arch, and the connecting pipe 630 is used to connect the branch stent corresponding to the branch blood vessel on the aortic arch.

[0125] In the present embodiment, the connecting pipe 630 is fixedly connected to the through hole 620 by sewing. The groove part 600 includes three connecting pipes 630, two connecting pipes 630 are arranged at the proximal end of the groove part 600, and one connecting pipe 630 is arranged at the distal end of the groove part 600, and the three connecting pipes 630 correspond to three branch blood vessels on the aortic arch respectively. The edge of the through hole 620 is sewn with a developing ring 640 by sewing thread, which is used to display the position of the connecting pipe 630, so as to facilitate the connection of the branch stent with the covered stent 10 and the implantation into the branch blood vessel.

[0126] The edge of the groove bottom film 610 is connected with the cover 110 by sewing, and the groove bottom film 610 is provided with a groove support 650. The groove support 650 is a support rod connected to the bending section stent, and the groove bottom film 610 is sewn on the support rod, or the groove support 650 is a suture line sewn on the groove bottom film 610, which is used to increase the support strength of the bottom film.

[0127] As Figure 20 And Figure 21As shown, the stent body 100 includes a keel 200, the bending segment 310 includes a plurality of bending turns 311, the plurality of bending turns 311 are sequentially connected and fixed on the keel 200, the adjacent bending turns 311 are connected through a bending sleeve 410, and the bending sleeve 410 is sleeved on the keel 200. The bending sleeve 410 is curved, so that the bending sleeve 410 drives the keel 200 and the bending turns 311 to bend the entire bending segment 310 to adapt to the shape of the aortic arch.

[0128] The groove part 600 is arranged on one side close to the keel 200. Due to the keel 200, the stent graft 10 of the embodiment is used for implanting at the aortic arch, and the bending degree of the blood vessel at the aortic arch is large. By arranging the keel 200 towards the large bending side of the aortic arch, the support of the stent graft 10 to the aortic arch as a whole can be enhanced, and the displacement of the stent graft 10 can be avoided. However, after the stent graft 10 is implanted in the blood vessel for a long time, the resilience of the keel 200 can cause stimulation to the inner wall of the blood vessel, which can easily lead to new aortic rupture. The present application drives the keel 200 to bend the entire bending segment 310 to better fit the shape of the blood vessel. Not only does the arrangement of the keel 200 ensure the overall support of the stent graft 10 to achieve the purpose of protecting the blood vessel, but also the use of the bending sleeve 410 reduces the elastic straightening force of the keel 200 and the bending segment 310 and the stress formed thereby, thereby avoiding new aortic rupture.

[0129] The bending turn 311 includes a high wave segment 312 and a low wave segment 313 connected in sequence, the high wave segment 312 is arranged on one side close to the keel 200, the low wave segment 313 is arranged on one side away from the keel 200, the axial height of the high wave segment 312 is greater than the axial height of the low wave segment 313, and in other embodiments, the axial height of the high wave segment 312 is greater than or equal to the axial height of the main body turn 331, and the distance between adjacent high wave segments 312 is greater, so that the branch stent can pass through the adjacent bending turns 311 more easily, thereby facilitating the implantation of the branch stent, saving operation time, and improving the success rate of the operation.

[0130] Compared with the existing stent graft 10, the present embodiment is provided with the groove part 600 on the bending segment 310, and the groove part 600 corresponds to the aortic arch after the stent graft 10 is implanted in the blood vessel. The connecting pipe 630 is arranged in the groove part 600, and the connecting pipe 630 is used to adapt to the branch stent, so that the stent graft 10 and the branch blood vessel on the aortic arch are connected through the branch stent. In addition, the bending turn 311 can better support the inner wall of the blood vessel at the aortic arch under the support of the keel 200, and the bending sleeve 410 arranged in a curved shape on the bending segment 310 makes the entire bending segment 310 curved to adapt to the shape of the aortic arch, thereby reducing the pressure of the stent graft 10 on the inner wall of the blood vessel, reducing the stimulation of the stent graft 10 to the blood vessel, and preventing new rupture.

[0131] The aortic arch periphery can be isolated and treated by other parts of the non-groove part 600 of the stent graft 10, thereby adapting to the vascular lesions of the aortic arch periphery. The blood flow of the upper branch vessels of the aortic arch and the treatment of the vascular lesions of the aortic arch periphery are considered.

[0132] In this embodiment, the stent body can further include a plurality of curved segments 310, and the groove part 600 is arranged on one of the curved segments 310, thereby adapting to the vascular lesions of different parts of the aortic arch periphery, such as the ascending aorta, etc.

[0133] As shown in Figure 20 The stent body 100 further includes a body segment 330 including a plurality of body loops 331 arranged at intervals, and the sleeve assembly 400 includes a connecting sleeve 420 for fixing the body loops 331 on the keel 200, and the stoma graft 110 is fixed by suturing between the body loops 331. As shown in Figure 8 The connecting sleeve 420 is provided with a pressure tooth groove 430, and when the stoma graft 110 is fixed on the body loop 331, the suture is bound in the pressure tooth groove 430 on the connecting sleeve 420. The suture bound in the pressure tooth groove 430 can increase its fixing strength and avoid relative movement between the stoma graft 110 and the body loop 331 due to pulling force.

[0134] In this embodiment, the stent body 100 further includes a connecting segment 320 connected to the keel 200 through the connecting sleeve 420. Since the curved loop 311 at the groove part 600 is arranged separately from the stoma graft 110, this embodiment connects the curved segment 310 and the connecting segment 320 through the keel 200, so that the transition of the curved loop 311 on the groove part 600 is smoother, avoiding the curved loop 311 from being raised outward when the stent graft 10 is bent, which can cause excessive stimulation of the curved loop 311 to the inner wall of the blood vessel, thereby avoiding other adverse consequences such as new breakage in the blood vessel.

[0135] As shown in Figure 22 to Figure 24 The stent body 100 is provided with a half-release device 700, the half-release device 700 includes a binding unit 710 for binding the stent body 100 and a limiting unit 720 movably connected with the binding unit 710, and the limiting unit 720 controls the release of the binding unit 710.

[0136] The binding unit 710 includes a limiting ring 711 arranged on the loop assembly 300 and a binding line 712 passing through the limiting ring 711. The limiting unit 720 includes a limiting rod 721, and the loop assembly 300 is provided with at least two limiting rings 711, and the two ends of the binding line 712 pass through the limiting rings 711 respectively, and the binding line 712 and the limiting rod 721 are adapted and used for circumferentially restraining the stent graft 10.

[0137] In the embodiment, the binding unit 710 comprises a plurality of limiting rings 711 arranged circumferentially on the stent 10, so that the binding line 712 is more stable when fixed on the stent 10. The limiting ring 711 is sleeved on the wave coil assembly 300 and is sutured and fixed on the covering membrane 120.

[0138] Both ends of the binding line 712 are provided with buckles 713, and the limiting rod 721 is used for simultaneously penetrating the buckles 713 at both ends of the binding line 712. Meanwhile, the length of the binding line 712 is less than the circumference of the cross section of the stent body 100.

[0139] In other embodiments, the limiting unit 720 can also comprise a limiting wire for simultaneously penetrating the buckles 713 at both ends of the binding line 712.

[0140] In the embodiment, the semi-release device 700 is arranged on the surface of the stent 10. After the stent 10 is completely released from the delivery device, the stent 10 is in a semi-released state under the constraint of the semi-release device 700. The stent 10 in the semi-released state is circumferentially constrained by the binding line 712. At this time, the binding line 712 binds the stent 10 in the circumferential direction of the stent 10, and the limiting rod 721 simultaneously penetrates the buckles 713 at both ends of the binding line 712.

[0141] The stent 10 in the semi-released state is not in close contact with the blood vessel wall. The operator can adjust the axial and circumferential positions of the stent 10 according to the actual situation. After accurate positioning, the constraint of the semi-release device 700 is released, so that the stent 10 is deployed and adheres to the wall. When the constraint of the semi-release device 700 is released, the limiting rod 721 is pulled out of the buckles at both ends of the binding line 712. The stent 10 loses the constraint and expands under the elastic force of itself, so as to completely adhere to the wall.

[0142] In the embodiment, the binding unit 710 is arranged on each wave coil assembly 300, so that the stent 10 is uniformly stressed in the semi-released state.

[0143] Since the stent 10 of the embodiment needs to correspond to the branch vessels above the aortic arch when implanted in the blood vessel, it is difficult to ensure that the recess portion 600 is aligned with the branch vessels above the aortic arch when the stent 10 is released. Therefore, the semi-release device 700 is arranged on the stent 10, and the position adjustment of the stent 10 is realized through the semi-release device 700.

[0144] Due to the groove part 600 provided on the bending segment 310 of the application, and the groove part 600 is provided on the covering film 110 and recessed into the stent body 100, the keel 200 in the groove part 600 is in direct contact with the inner wall of the blood vessel, and the stent body 100 with the bending sleeve 410 has stronger anchoring force after the covering stent 10 is deployed and adheres to the wall, which can avoid the displacement of the covering stent 10 under the long-term scouring of the blood flow.

[0145] However, due to the presence of the bending segment 310 of the covering stent 10, compared with the traditional straight cylinder stent, if the position of the covering stent 10 is not accurate when released, the bending segment 310 will adhere to the wall in advance, which makes it difficult to adjust the position of the covering stent 10. The application provides a half-release device 700 on the covering stent 10, and the covering stent 10 is in a half-release state after being released from the delivery system. At this time, the bending segment 310 is in a restrained state and has not yet adhered to the blood vessel wall, so the covering stent 10 can move without scratching the blood vessel wall. The operator can adjust the axial and circumferential positions of the covering stent 10 according to the situation, so that the groove part 600 is opposite the branch blood vessels on the aortic arch.

[0146] In addition, the application bends the entire bending segment 310 by the bending sleeve 410, so that the bending of the bending segment 310 as a whole is more uniform, and the transition of the limiting rod 721 of the restraint unit 710 when passing through the limiting ring 711 in sequence is smoother. At the same time, the restraint line 712 can be hooked in the pressure tooth groove 430 on the bending sleeve 410, which can prevent the restraint line 712 from shifting during the movement of the limiting rod 711.

[0147] In this embodiment, when the covering stent 10 is in a half-release state, the buckle ring 713 at both ends of the restraint line 712 is located in the middle of the groove part 600, so that the stress on the groove part 600 is more uniform. At the same time, the keel 200 is axially arranged along the middle of the groove part 600. When the restraint line 712 is in a half-release state, it can be hooked in the pressure tooth groove 430 on the bending sleeve 410, and the limiting rod 721 passes through the buckle ring 713 of the limiting unit 720 in sequence. At this time, the limiting rod 721 is restrained by a plurality of buckle rings 713 and has the same bending shape as the keel 200, thereby avoiding the covering stent 10 in a half-release state from scratching the blood vessel wall when adjusting the position, and ensuring the safety of the operation.

[0148] Through the above technical solutions of the embodiment, by providing the groove part 600 corresponding to the aortic arch on the bending segment 310, the covering stent 10 can well cope with the vascular lesions around the aortic arch. And the setting of the bending segment 310 can well adapt to the shape of the aortic arch, reduce the stimulation of the covering stent 10 to the inner wall of the blood vessel. It takes into account the blood circulation of the branch blood vessels on the aortic arch and the treatment of vascular lesions around the aortic arch.

[0149] In summary, the covered stent prepared by the preparation method has good physical properties, can be made according to the shape of the specific diseased blood vessel, makes the stent more conform to the shape of the blood vessel itself, can reduce the elastic straightening force generated after the existing stent is passively bent at the curved part such as the aortic arch, and the stress formed thereby, reduces and prevents the aortic new break caused by the stent.

[0150] The above merely describes the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, any changes or replacements within the technical scope disclosed by the present application can be easily thought by those skilled in the art, and should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A covered stent comprising a stent body and a covering disposed on the stent body, characterized in that, The bracket body comprises a keel, a wave ring assembly, and a sleeve joint assembly for connecting the keel and the wave ring assembly; the wave ring assembly comprises at least one curved segment connected to the keel, and the curved segment comprises a plurality of curved wave rings arranged on the keel in sequence; the sleeve joint assembly comprises a plurality of curved sleeves for connecting the curved wave rings and the keel; the curved segment is provided with a recessed groove portion recessed towards the inside of the bracket body; The sleeve joint assembly further comprises a pressing tooth groove recessed towards the inside of the curved sleeve, and the pressing tooth groove is used for connecting and fixing the curved segment and the keel; the curved sleeve comprises a first pressing surface and a second pressing surface arranged oppositely, and the pressing tooth groove is arranged on the first pressing surface and / or the second pressing surface.

2. The stent graft of claim 1, wherein, The recessed groove portion is arranged on one side close to the keel.

3. The stent graft of claim 2, wherein, The curved wave ring comprises a high wave segment and a low wave segment connected in sequence, the high wave segment is arranged on one side close to the keel, and the low wave segment is arranged on one side away from the keel; the axial height of the high wave segment is greater than the axial height of the low wave segment.

4. The stent graft of claim 3, wherein, The bracket body further comprises a main body segment arranged at the distal end of the curved segment, the main body segment is arranged in a straight cylinder shape, and the main body segment comprises a plurality of main body wave rings connected to the keel in sequence; the axial height of the high wave segment is greater than or equal to the axial height of the main body wave ring.

5. The stent graft of claim 1, wherein, The bracket body is provided with a half-release device, the half-release device comprises a binding unit for binding the bracket body and a limiting unit movably connected with the binding unit; the binding unit comprises at least two limiting rings arranged on the wave ring assembly and a binding line passing through the limiting rings, and the two ends of the binding line pass through the limiting rings and are matched with the limiting unit respectively.

6. The stent graft of claim 5, wherein, The length of the binding line is less than the circumference of the cross section of the bracket body, the limiting unit comprises a limiting rod, and the two ends of the binding line are provided with buckles; the limiting rod is used for simultaneously penetrating the buckles at the two ends of the binding line.

7. The stent graft of claim 1, wherein, The bending directions and / or bending amplitudes of the plurality of curved sleeves are the same or different.

8. The stent graft of claim 1, wherein, The adjacent curved wave rings are connected by connecting rods, the curved wave rings are fixedly connected to the connecting rods by the curved sleeves, and a plurality of connecting rods are connected in sequence to form part of the keel; the curved wave rings and the connecting rods are integrally woven by weaving wires, and the adjacent curved wave rings are connected end to end by the connecting rods.

9. The stent graft of claim 1, wherein, The number and / or shape of the pressing tooth grooves arranged on the first pressing surface of the curved sleeve are different from those of the pressing tooth grooves arranged on the second pressing surface.

10. The stent graft of claim 9, wherein, The pressing tooth grooves comprise first pressing grooves arranged on the first pressing surface and second pressing grooves arranged on the second pressing surface; the number of the first pressing grooves is less than that of the second pressing grooves, and the first pressing grooves and the second pressing grooves are arranged in a staggered manner.

11. The stent graft of claim 10, wherein, The curved sleeve is bent towards the inside of the bracket body; the first pressing surface is arranged towards the inside of the bracket body, and the second pressing surface is arranged towards the outside of the bracket body.

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