Thoracic Aortic Stent Graft

Abstract

The present invention provides a thoracic aortic covered stent, which relates to the field of medical devices. The proximal section of the main support frame of the main stent includes a wavy proximal stent ring, and at least two groups of fish-mouth stents that are integrally connected to the proximal stent ring and extend to the proximal side of the proximal stent ring; each group of fish-mouth stents includes two symmetrically arranged arc-shaped stent units; the planes where each arc-shaped stent unit is located are respectively inclined radially outward from the distal end to the proximal end along the main covering; the arc-shaped stent units of each adjacent group of fish-mouth stents cross each other in a grid shape, and each two intersecting arc-shaped stent units overlap each other. The thoracic aortic covered stent provided by the present invention has good radial support force, softness and elasticity, can avoid internal leakage, and avoid the proximal end of the stent irritating the inner wall of the blood vessel; it can also avoid the clamping of the branch stent, reduce the compression size of the integrated branch stent, and improve the tolerance of the misalignment between the opening of the embedded stent and the opening of the branch blood vessel.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a thoracic aorta covered stent. Background Art

[0002] Aortic disease is a common disease in the spectrum of cardiovascular diseases, and its incidence is increasing rapidly. Diseases such as aortic aneurysm, atherosclerosis, aortic dissection, aortic ulcer, etc., greatly endanger human health and even life.

[0003] When the patient's aortic dissection or thoracic aortic aneurysm lesions involve the aortic arch, open surgery is the first choice to replace the patient's diseased blood vessels using artificial blood vessels or hybrid surgery of artificial blood vessels + covered stents. However, diseases involving the aortic arch are very complicated, and open surgery has certain limitations. It requires extracorporeal thoracotomy and extracorporeal circulation, which is difficult to operate. In addition, deep hypothermic cerebral perfusion, circulatory arrest and other operations cause great damage to the patient's brain, causing surgical trauma, postoperative complications, and even brain death in patients. The postoperative stroke rate and mortality rate are significant. For elderly patients and patients with weak tolerance, endovascular repair technology is undoubtedly a better choice, reducing the risk of surgery. As endovascular treatment technology gradually breaks through the limitations of anatomical conditions, aortic arch endovascular repair has become a major method for treating aortic arch diseases. Covered stents are implanted in the aortic arch, descending aorta, and three branches on the aortic arch through interventional methods, thereby isolating the blood flow at the lesion site and establishing a new blood flow channel. It has the advantages of low risk, low trauma, fast recovery, and simplified surgical procedures.

[0004] Specifically, the human thoracic aorta mainly includes the aortic arch vessels, the ascending aorta vessels, and the descending aorta vessels. The convex side of the aortic arch vessels is its greater curvature, and the concave side is its lesser curvature. There are three branch vessels on the greater curvature, which are the innominate artery (also known as the brachiocephalic artery), the left common carotid artery, and the left subclavian artery. Some dissections or aneurysms may occur in the aortic arch vessels. At this time, an aortic arch endovascular repair is performed, and an aortic stent graft is implanted in the aortic arch vessels for treatment. When the lesion involves the branch vessels, in addition to implanting the aortic stent graft, a branch stent needs to be implanted in the corresponding branch vessels. The implanted aortic stent graft and branch stent should not block the branch vessels to maintain blood supply.

[0005] Although the above-mentioned aortic arch endovascular repair can effectively reduce the risk of trauma and stroke in patients, the existing technology still has great shortcomings, mainly reflected in:

[0006] ① During the entire vascular pulsation cycle, the ascending aorta has a larger pulsation amplitude than other segments of the blood vessels, and because the ascending aorta has greater elasticity, it produces greater radial displacement and axial expansion during the pulsation process than other segments of the blood vessels. Existing aortic stent grafts often use a Z-shaped wire-wound stent structure, which is characterized by strong support but no axial expansion. Therefore, after this stent is implanted in the ascending aorta, as the ascending aorta moves radially and axially, it will continuously stimulate the inner wall of the blood vessel, causing new endothelial ruptures and eventually forming a new dissection.

[0007] ② For the integrated branch stent, during the implantation process, the aortic stent graft needs to be constricted. First, the aortic stent graft is released from the sheath, and then the aortic stent graft is fully opened after the branch stent is implanted into the branch vessel. The integrated branch stent in the prior art often constricts the aortic stent graft through a membrane sleeve, which also increases the overall compression volume of the stent. A larger delivery sheath is required to complete the implantation surgery, which increases the puncture diameter of the patient's blood vessels. In addition, some patients with tortuous and small blood vessels cannot use it.

[0008] ③ For the integrated branch stent, i.e. the aortic stent graft with branches, the branch stents in the existing technology are mostly straight-cylindrical, in the form of a wire-wound Z-shaped stent connected to the coating. This structure results in a smaller rotational range of motion for the branch stent than the aortic stent graft. When the angle between the patient's innominate branch artery and the aortic arch is large, the innominate branch stent will be compressed and closed;

[0009] ④ For the integrated branch stent, i.e., the aortic stent graft with branches, the implantation method is to compress the integrated branch stent into the delivery sheath and then implant it into the aortic arch area at one time, first release the branch stent, and then release the aortic stent graft. When the integrated branch stent is compressed into the delivery sheath, the internal space of the sheath occupied is relatively large. In order to minimize the space occupied by the stent in the sheath after compression, it is expected that the branch stent can remain parallel to the axis of the aortic stent graft after compression. However, in the prior art, a small stent is often required to be placed at the junction of the branch stent and the aortic stent graft (otherwise the branch stent will be occluded after release). This causes the branch stent to be compressed and folded, and the small stent placed at the junction is severely deformed, resulting in a further increase in the occupied space. The required delivery sheath has a thick diameter, resulting in a larger diameter of the patient's blood vessel puncture. In addition, some patients with tortuous and small blood vessels cannot use it.

[0010] ⑤ For modular branch stents, first implant an aortic stent graft with an embedded inner part, then select a branch guidewire through the embedded part into the branch artery, and implant the branch stent through the branch guidewire. In the prior art, the embedded part is mostly a cylinder with a consistent diameter, and the size of the embedded opening on the aortic stent graft is consistent with the diameter of the embedded part, resulting in too little operating space during the selection of the branch guidewire into the branch artery; however, the intervals between the branch vessels of different patients vary greatly (the position of the left subclavian artery is particularly erratic), and the size of the embedded opening in the prior art is relatively small, and the tolerance rate for the misalignment between the embedded opening position and the branch vessel opening position is low. Summary of the invention

[0011] The object of the present invention is to provide a thoracic aorta covered stent to alleviate at least one of the above-mentioned technical problems existing in the prior art.

[0012] To achieve the above objectives, the embodiments of the present invention adopt the following technical solutions:

[0013] The embodiment of the present invention provides a thoracic aorta covered stent, comprising a main body stent, wherein the main body stent comprises a straight-cylindrical main body covering and a main body support frame connected to the main body covering;

[0014] The main body support frame includes a proximal section, a middle section and a distal section arranged along the axial direction of the main body covering; the proximal section includes a wavy proximal end support ring whose central axis extends along the axial direction of the main body covering, and at least two groups of fish mouth supports integrally connected to the proximal end support ring and extending to the proximal side of the proximal end support ring;

[0015] Each group of the fish-mouth stents comprises two symmetrically arranged arc-shaped stent units; the planes where the arc-shaped stent units are located are respectively inclined outwardly along the radial direction of the main body covering from the distal end to the proximal end; the arc-shaped stent units of each adjacent two groups of the fish-mouth stents are intertwined with each other in a grid shape, and each two intersecting arc-shaped stent units of the proximal section are overlapped with each other.

[0016] In this embodiment, the proximal section of the main support frame includes a proximal end support ring and at least two groups of fish-mouth supports. The planes of the two symmetrical arc-shaped support units of each group of fish-mouth supports form a "fish-mouth" shape with an opening toward the proximal end. The arc-shaped support units of the two adjacent groups of fish-mouth supports cross each other in a grid shape, thereby achieving at least the following functions:

[0017] ① The wavy proximal stent ring as a wire-wound stent can provide a higher radial support force to avoid the internal leakage of the proximal side after the main stent is released into the aortic arch blood vessels;

[0018] ② Compared with the wire-wound stent, the fish-mouth stent has higher flexibility, so that the proximal end of the main stent can have a certain radial support force, and can avoid the end puncturing the intima of the ascending aorta, avoiding the occurrence of new ruptures and new dissections;

[0019] ③ The arc-shaped stent units of each two adjacent groups of fish-mouth stents cross each other in a grid shape, which has good telescopic performance compared to the wire-wound stent, so that the proximal section of the main stent can undergo adaptive changes in axial and radial dimensions with the pulsation of the ascending aorta, avoiding the stent from stimulating the inner wall of the blood vessel with the pulsation of the ascending aorta.

[0020] In summary, the thoracic aortic covered stent provided in the embodiment of the present invention has good radial support force, softness and elasticity, which can avoid internal leakage and prevent the proximal end of the stent from irritating the inner wall of the blood vessel, causing new intimal ruptures and ultimately forming new dissections.

[0021] In an optional technical solution of an embodiment of the present invention, the proximal end bracket ring is woven integrally with each of the arc-shaped bracket units, and the two ends of one arc-shaped bracket unit of each group of the fish-mouth bracket converge with the two ends of another arc-shaped bracket unit in a one-to-one correspondence and overlap with each other.

[0022] In an optional technical solution of an embodiment of the present invention, the proximal edge of the main body coating is located on the proximal side of the overlapping point between each two overlapping arc-shaped bracket units; the arc-shaped bracket unit is fixedly connected to the proximal edge of the main body coating, and all other inflection points on the proximal bracket ring except the overlapping point between each two overlapping arc-shaped bracket units are fixedly connected to the main body coating.

[0023] In an optional technical solution of an embodiment of the present invention, at least the proximal section of the main body covering is connected with a binding coil and a plurality of limiting rings arranged at intervals along the circumference of the main body covering; the proximal section of the main body support frame also includes a wavy transition bracket ring provided on the distal side of the proximal bracket ring; the binding coil provided on the proximal section of the main body covering is located between the proximal inflection point and the distal inflection point of the transition bracket ring, and the middle part of the binding coil is fixedly connected to the main body covering. In the restrained state, the two ends of the binding coil respectively pass through the plurality of limiting rings on the corresponding sides along the circumference of the main body covering and then merge; the conveyor release wire passes through the two ends of the binding coil to circumferentially restrain the proximal section of the main body bracket.

[0024] Further optionally, every two adjacent limiting rings are staggered with each other in the axial direction of the main body coating.

[0025] In addition, in order to alleviate other technical problems described in the background technology, the embodiment of the present invention also has the following optional technical solutions, and the specific functional effects that can be achieved are referred to the specific implementation method part of this specification:

[0026] In an optional technical solution of an embodiment of the present invention, the thoracic aorta stent graft further includes a branch stent. A branch opening is provided on the main body graft, with one end of the branch stent close to the branch opening being the proximal end of the branch stent and the other end being the distal end of the branch stent. The branch stent includes a proximal frustum segment docking with the branch opening and a distal cylindrical segment connected to the proximal frustum segment away from the branch opening. The proximal frustum segment includes a frustum segment graft whose diameter gradually decreases from the proximal end to the distal end and a frustum-shaped grid stent connected to the frustum segment graft and whose diameter gradually decreases from the proximal end to the distal end; the frustum segment graft is fixedly connected or integrally connected to the main body graft; the proximal intersection of the frustum-shaped grid stent is fixedly connected to the frustum segment graft, and the distal intersection of the frustum-shaped grid stent is separated from the frustum segment graft. The distal cylindrical segment includes a cylindrical segment graft and a multi-circle wavy stent ring fixedly connected to the cylindrical segment graft.

[0027] In an optional technical solution of an embodiment of the present invention, the thoracic aorta covered stent also includes an embedded stent; an embedded opening is provided on the main body covering, and the embedded opening is circular or elliptical. The embedded stent is arranged inside the main body covering, including a hollow cylindrical segment and a hollow hemispherical segment connected to each other, and one end of the hollow hemispherical segment away from the hollow cylindrical segment is connected to the embedded opening; the hollow hemispherical segment is a hollow semi-spherical segment or a hollow semi-elliptical segment.

[0028] In an optional technical solution of the embodiment of the present invention, a window is further provided on the main body coating.

[0029] In an optional technical solution of an embodiment of the present invention, a branch structure is provided on the main body coating, and the branch structure includes at least one of a branch bracket, a window and an embedded bracket; the middle section of the main body support frame includes a plurality of middle wave rings, with the proximal end of the main body coating as the top end and the distal end as the bottom end: each trough of each middle wave ring is on the same radial circumferential surface of the main body coating, and the crest of each middle wave ring at the edge of the branch structure is on the distal side of other crests.

[0030] In particular, in the embodiments of the present invention, “and / or” indicates that the first feature before “and / or” and the second feature after “and / or” include the following specific setting methods: (1) only the first feature is set, and the second feature is not set; (2) only the second feature is set, and the first feature is not set; (3) the first feature and the second feature are set at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 A schematic diagram of the overall structure of a first optional structure of a thoracic aortic covered stent provided by an embodiment of the present invention at a first viewing angle;

[0033] Figure 2 A schematic diagram of the overall structure of a first optional structure of a thoracic aortic covered stent provided by an embodiment of the present invention from a second viewing angle;

[0034] Figure 3 An enlarged view of the proximal local structure of the first optional structure of the thoracic aortic covered stent provided in an embodiment of the present invention;

[0035] Figure 4 An axonometric diagram of the connection structure between the proximal stent ring and the fish-mouth stent in the thoracic aorta covered stent provided in an embodiment of the present invention;

[0036] Figure 5 A schematic diagram of the connection relationship between the binding coil, the limiting ring and the main stent in the thoracic aortic covered stent provided in an embodiment of the present invention;

[0037] Figure 6 It is a schematic diagram of the proximal end section of the main support frame being circumferentially bounded by the release wire in the bound state;

[0038] Figure 7 A schematic diagram of the overall structure of a branch stent in a thoracic aortic stent graft provided by an embodiment of the present invention;

[0039] Figure 8 An axonometric diagram of the overall structure of an embedded stent in a thoracic aorta covered stent provided in an embodiment of the present invention from one viewing angle;

[0040] Fig. 9 An axonometric diagram of the overall structure of the embedded stent in the thoracic aorta covered stent provided in an embodiment of the present invention from another perspective.

[0041] Icons: 100-main stent; 110-main stent coating; 11-proximal stent ring; 12-fish-mouth stent; a-lap point; b-fixed connection point; 13-transition stent ring; 141-binding coil; 142-limiting ring; 15-middle wave ring; 200-branch stent; 210-proximal frustum segment; 211-frustum-shaped grid stent; 2111-proximal intersection; 2112-distal intersection; 212-frustum segment coating; 220-distal cylindrical segment; 300-embedded stent; 310-hollow cylindrical segment; 320-hollow hemispherical segment; 400-window; 500-release wire. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0043] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] It should be noted that like reference numerals and letters denote similar items in the drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0045] In the description of the present invention, it should be noted that:

[0046] Unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] The orientation or position relationship indicated by the terms "proximal", "distal", "front end", "rear end", "axial", "radial", "circumferential", "inner" and "outer" are based on the orientation or position relationship shown in the drawings, or are the orientation or position relationship in which the product of the invention is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0048] The terms “first”, “second”, etc. are only used for distinguishing descriptions and do not indicate the total number or relative position in time and / or space, and cannot be understood as indicating or implying relative importance.

[0049] In the following, some embodiments of the present invention are described in detail in conjunction with the accompanying drawings. In the absence of conflict, the features of the following embodiments and the optional embodiments in the embodiments can be combined with each other.

[0050] This embodiment provides a thoracic aortic stent graft, referring to Figures 1 to 4 The thoracic aorta covered stent comprises a main stent 100, the main stent 100 comprises a straight cylindrical main covering 110 and a main support frame connected to the main covering 110; the main support frame comprises a proximal section, a middle section and a distal section arranged along the axial direction of the main covering 110; wherein the proximal section comprises a wavy proximal end support ring 11 whose central axis extends along the axial direction of the main covering 110, and at least two groups of fish mouth supports 12 which are integrally connected to the proximal end support ring 11 and extend to the proximal side of the proximal end support ring 11; Each group of fish-mouth brackets 12 includes two symmetrically arranged arc-shaped bracket units; the planes where each arc-shaped bracket unit is located are respectively inclined outward from the distal end to the proximal end along the radial direction of the main body covering 110, that is, the planes of the two symmetrical arc-shaped bracket units in each group of fish-mouth brackets 12 form a "fish-mouth" shape with an opening toward the proximal end; the arc-shaped bracket units of each adjacent group of fish-mouth brackets 12 cross each other in a grid shape, and each two intersecting arc-shaped bracket units of the proximal end section of the main body support frame overlap each other, and the overlap point a is as shown in FIG. Figure 3 shown.

[0051] In this embodiment, the proximal section of the main support frame includes a proximal end support ring 11 and at least two groups of fish mouth supports 12. The planes of the two symmetrical arc-shaped support units of each group of fish mouth supports 12 form a "fish mouth" shape with an opening facing the proximal end. The arc-shaped support units of the two adjacent groups of fish mouth supports 12 cross each other in a grid shape, thereby achieving at least the following functions:

[0052] ① The wavy proximal stent ring as a wire-wound stent can provide a high radial support force to prevent the proximal side bleeding from internal leakage after the main stent 100 is released into the aortic arch blood vessel;

[0053] ② The fish-mouth stent 12 has higher flexibility than the wire-wound stent, so that the proximal end of the main stent can have a certain radial support force, and can prevent the end from puncturing the intima of the ascending aorta, avoiding the occurrence of new ruptures and new dissections;

[0054] ③ The arc-shaped stent units of each two adjacent groups of fish-mouth stents 12 cross each other in a grid shape, which has good telescopic performance compared to the wire-wound stent, so that the proximal section of the main stent can undergo adaptive changes in axial and radial dimensions with the pulsation of the ascending aorta, thereby avoiding the stent irritating the inner wall of the blood vessel with the pulsation of the ascending aorta.

[0055] In summary, the thoracic aortic covered stent provided in this embodiment has good radial support, softness and elasticity, which can avoid internal leakage and prevent the proximal end of the stent from irritating the inner wall of the blood vessel, causing new intimal ruptures and ultimately forming new dissections.

[0056] Furthermore, if Figure 3 and Figure 4 As shown, in the optional technical solution of this embodiment, the proximal end bracket ring 11 is woven integrally with each arc-shaped bracket unit, and the two ends of an arc-shaped bracket unit of each group of fish mouth brackets 12 are connected to the two ends of another arc-shaped bracket unit in a one-to-one correspondence and overlapped with each other, and the overlap point a is as shown in FIG. Figure 2 shown.

[0057] Reference Figure 3 In the optional technical solution of this embodiment, the proximal edge of the main body coating 110 is located on the proximal side of the overlapping point a between each of the two intersecting arc-shaped bracket units; the arc-shaped bracket unit is fixedly connected to the proximal edge of the main body coating 110, and the fixed connection point b is as shown in FIG. Figure 3 As shown, in addition, all inflection points (wave crests or wave troughs) on the proximal stent ring 11, except for the overlapping point a between two intersecting arc stent units, are fixedly connected to the main body coating 110. The fixed connection point b ensures the radial support force, and the overlapping point a ensures the flexibility of the proximal section of the main stent 100 to change its size as the aorta rises and pulsates.

[0058] The above aortic stent graft is suitable for the case where only the main stent 100 is included. According to the specific implantation site, one, two or three window openings or branch stents or embedded stents corresponding to the branch blood vessel openings can be selectively provided. When the above aortic stent graft also includes a branch stent, when the thoracic aortic stent graft is delivered to the aortic arch blood vessel of the patient by using a conveyor, it is necessary to first perform constriction on the proximal section of the main stent graft 100, first release the main stent from the sheath of the conveyor, and then fully open the main stent after the branch stent is implanted into the branch blood vessel. The prior art uses the membrane sleeve to constrict the diameter, which results in a larger overall compressed volume of the thoracic aortic stent graft during delivery, and a larger-sized conveyor sheath is required to complete the implantation operation, resulting in a larger puncture diameter of the patient's blood vessel, and the problem that some patients with tortuous and small blood vessels cannot use the stent graft. With respect to this technical problem:

[0059] Reference Figure 2 and Figure 5 In the optional technical solution of this embodiment, at least the proximal section of the main body covering 110 is connected with a binding coil 141 and a plurality of limiting rings 142 arranged at intervals along the circumference of the main body covering 110; the proximal section of the main body support frame also includes a wavy transition support ring 13 arranged on the distal side of the proximal end support ring 11; the binding coil 141 arranged on the proximal section of the main body covering 110 is located between the proximal inflection point and the distal inflection point of the transition support ring 13, and the middle part of the binding coil 141 is fixedly connected to the main body covering 110. Figure 6 In the restrained state, the two ends of the restraining coil 141 pass through the multiple limiting rings 142 on the corresponding side along the circumference of the main body coating 110 and then merge; the hard release wire 500 of the conveyor passes through the two ends of the restraining coil 141 to circumferentially restrain the proximal section of the main stent 100. Compared with the use of a membrane sleeve to restrain the proximal section of the main stent 100, the mutually coordinated structure of the release wire 500, the restraining coil 141 and the limiting ring 142 has a smaller volume after radial compression, thereby reducing the space occupied by the thoracic aortic stent graft inside the conveyor sheath during transportation, that is, reducing the diameter of the thoracic aortic stent graft after compression, and then reducing the outer diameter of the required conveyor sheath, so that the conveyor sheath can also be used for some patients with tortuous and small blood vessels. At the same time, the puncture caliber of the patient's blood vessels is reduced, which is more conducive to the patient's postoperative recovery. It should be noted that, in other optional implementations in which other sections of the main support 100 also have bundle diameter requirements during transportation, other sections of the main body coating 110 can also be adaptively provided with the above-mentioned binding coils 141 and limiting rings 142.

[0060] Further optionally, each two adjacent limiting rings 142 are staggered with each other in the axial direction of the main body coating 110, thereby further reducing the overlapping volume of the limiting rings 142 in the circumferential direction (radial circumferential direction) of the main body coating 110, thereby further reducing the diameter of the thoracic aortic covered stent after compression, thereby reducing the outer diameter of the required delivery device sheath.

[0061] Reference Figure 1 and Figure 2 When the thoracic aorta covered stent includes a branch stent 200 (that is, an integrated branch stent) in addition to the main stent 100, a branch opening is provided on the main covering 110, and the end of the branch stent 200 close to the branch opening is the proximal end of the branch stent 200, and the other end is the distal end of the branch stent 200. The proximal end of the branch stent 200 is connected to the branch opening on the main covering 110; in this regard, the branch stents in the prior art are mostly straight cylindrical, and are presented in the form of a covering connected to a wire-wound Z-shaped stent. This structure results in a smaller rotational range of motion for the branch stent than that of the aortic stent graft. When the angle between the patient's innominate branch artery and the aortic arch is large, the innominate branch stent will be compressed and closed. In addition, in order to minimize the space occupied by the stent in the sheath after compression, it is expected that the branch stent can remain parallel to the axis of the aortic stent graft after compression. However, in the prior art, a small stent is often required to be placed at the junction of the branch stent and the aortic stent graft (otherwise the branch stent will be occluded after release). This causes the branch stent to be compressed and folded, and the small stent placed at the junction to be severely deformed, resulting in a further increase in the space occupied. The required conveyor sheath has a thick diameter, which results in a larger diameter for the patient's vascular puncture. Similarly, it cannot be used by some patients with tortuous and small blood vessels.

[0062] In view of this type of problem, in the optional technical solution of this embodiment, refer to Figure 1 and Figure 7 The branch stent 200 includes a proximal frustum section 210 docked with the branch opening and a distal cylindrical section 220 connected to the proximal frustum section 210 at one end (distal end) away from the branch opening. The proximal frustum section 210 includes a frustum section coating 212 whose diameter gradually decreases from the proximal end to the distal end and a frustum-shaped grid stent 211 connected to the frustum section coating 212 and whose diameter gradually decreases from the proximal end to the distal end; the frustum section coating 212 is fixedly connected or integrally connected to the main body coating 110; Figure 7As shown, the proximal intersection 2111 of the frustum-shaped grid stent 211 is fixedly connected to the frustum-segment coating 212, and the distal intersection 2112 of the frustum-shaped grid stent 211 is separated from the frustum-segment coating 212. The distal cylindrical segment 220 includes a cylindrical segment coating and a plurality of wavy stent rings fixedly connected to the cylindrical segment coating. Among them, the proximal intersection 2111 of the frustum-shaped grid stent 211 of the proximal frustum-segment 210 is fixedly connected to the frustum-segment coating 212, and the distal intersection 2112 is separated from the frustum-segment coating 212, so that the frustum-shaped grid stent 211 can change the radial size by telescoping during the swinging process, thereby adapting to the proximal shape change of the branch stent 200 at different swinging angles, and when the thoracic aorta covered stent is loaded into the outer sheath of the conveyor, the branch stent 200 can be smoothly parallel to the axis of the main stent 100. That is, by providing the proximal conical segment 210, the flexibility of the branch stent 200 in rotation can be ensured, and the proximal end of the branch stent 200 can be prevented from closing due to excessive swinging angle, and better elasticity can be provided, so that the branch stent 200 can be parallel to the axis of the main stent 100 after being radially compressed, thereby minimizing the space occupied by the thoracic aorta covered stent inside the conveyor sheath after being radially compressed, thereby adapting to the conveyor sheath with a smaller outer diameter.

[0063] Reference Figure 1 and Figure 2 , when the thoracic aortic stent graft includes an embedded stent 300 (i.e., a modular branch stent) in addition to the main stent 100; an embedded opening is provided on the main covering 110, and the embedded stent 300 is provided inside the main covering 110, and one end opening thereof is docked with the above-mentioned embedded opening. For this, it is necessary to first implant the main stent 100, and then select a branch guide wire into the branch artery through the embedded stent 300, and then implant the branch stent through the branch guide wire. In the prior art, the embedded stent is mostly cylindrical with a consistent diameter, and the size of the embedded opening on the main stent 100 is consistent with the diameter of the embedded stent, resulting in too small an operating space when the branch guide wire is selected into the branch artery, and a low tolerance for misalignment between the embedded opening position and the branch vessel opening position.

[0064] In view of this type of problem, in some optional technical solutions of this embodiment, refer to Figure 8 and Fig. 9The embedded opening of the main stent 100 is circular or elliptical, and the embedded stent 300 includes a hollow cylindrical section 310 and a hollow hemispherical section 320 that are connected to each other, and the end of the hollow hemispherical section 320 away from the hollow cylindrical section 310 is connected to the embedded opening of the main stent 100; wherein, the hollow hemispherical section 320 of the embedded stent 300 is a hollow hemispherical section or a hollow semi-elliptical section, so that the hollow cylindrical section 310 ensures that the internal blood flow of the main stent 100 is not blocked, and the hollow hemispherical section 320 expands the embedded opening area. When the branch guide wire passes through the hollow cylindrical section 310 and passes through the hollow hemispherical section 320, it can be easily selected into the branch blood vessel, that is, the tolerance rate of the misalignment between the embedded opening position and the branch blood vessel opening position is improved.

[0065] In addition, if Figure 1 As shown, in some optional technical solutions of this embodiment, a window 400 is further provided on the main body covering 110 .

[0066] In this embodiment, when a branch structure is provided on the main body coating 110, the branch structure includes at least one of a branch stent 200, a window 400, and an embedded stent 300, and the specific number of branch structures is determined according to the location of the patient's lesion; the middle section of the main body support frame includes a plurality of middle wave rings 15, with the proximal end of the main body coating 110 as the top end and the distal end as the bottom end: each trough of each middle wave ring 15 is on the same radial circumferential surface of the main body coating 110, and the crest of each middle wave ring 15 at the edge of the above-mentioned branch structure is located on the distal side of other crests. By means of the special-shaped design of the middle wave ring 15, the branch structure is avoided and good radial support force is provided for the opening edge of the branch structure, which is more conducive to the selection of the branch guide wire.

[0067] Finally, it should be noted that:

[0068] 1. In this specification, the methods of fixed connection between the membrane and each section of the stent include but are not limited to specific fixed connection methods such as suture connection or heat sealing connection;

[0069] 2. The above embodiments and optional implementation modes in this specification are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above optional implementation modes, or replace part or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention. In addition, it is emphasized again that the features of the embodiments in this specification and the optional implementation modes in the embodiments can be combined with each other without conflict.

Claims

1. A thoracic aorta covered stent, characterized in that: It comprises a main body support (100), wherein the main body support (100) comprises a straight-cylindrical main body coating (110) and a main body support frame connected to the main body coating (110); The main body support frame comprises a proximal section, a middle section and a distal section arranged along the axial direction of the main body coating (110); the proximal section comprises a wavy proximal end support ring (11) whose central axis extends along the axial direction of the main body coating (110), and at least two groups of fish mouth supports (12) integrally connected to the proximal end support ring (11) and extending toward the proximal side of the proximal end support ring (11); Each group of the fish-mouth stents (12) comprises two symmetrically arranged arc-shaped stent units; the planes on which the arc-shaped stent units are located are inclined outwardly from the distal end to the proximal end along the radial direction of the main body coating (110); the arc-shaped stent units of each two adjacent groups of the fish-mouth stents (12) intersect with each other in a grid shape, and each two intersecting arc-shaped stent units of the proximal section overlap with each other; The proximal end bracket ring (11) is integrally woven with each of the arc-shaped bracket units, and the two ends of one of the arc-shaped bracket units in each group of the fish-mouth brackets (12) are joined with the two ends of another arc-shaped bracket unit in a one-to-one correspondence and overlap each other; The proximal edge of the main body coating (110) is located on the proximal side of the overlapping point (a) between each two mutually intersecting arc-shaped bracket units; the arc-shaped bracket unit is fixedly connected to the proximal edge of the main body coating (110), and all other inflection points on the proximal bracket ring (11) except the overlapping point (a) between each two mutually intersecting arc-shaped bracket units are fixedly connected to the main body coating (110).

2. The thoracic aortic stent graft according to claim 1, characterized in that: At least the proximal end section of the main body coating (110) is connected to a binding coil (141) and a plurality of limiting rings (142) arranged at intervals along the circumference of the main body coating (110); The proximal end section of the main support frame further comprises a wavy transition support ring (13) provided on the distal end side of the proximal end support ring (11); The binding coil (141) provided at the proximal end section of the main body coating (110) is located between the proximal inflection point and the distal inflection point of the transition stent ring (13), and the middle portion of the binding coil (141) is fixedly connected to the main body coating (110); In the restrained state, the two ends of the restraining coil (141) respectively pass through the plurality of limiting rings (142) on the corresponding sides along the circumference of the main body coating (110) and then merge; the release wire (500) of the conveyor passes through the two ends of the restraining coil (141) to circumferentially restrain the proximal section of the main body support (100).

3. The thoracic aortic stent graft according to claim 2, characterized in that: Every two adjacent limiting rings (142) are staggered with each other in the axial direction of the main body coating (110).

4. The thoracic aorta covered stent according to claim 1, characterized in that: The thoracic aorta covered stent also includes a branch stent (200); The main body coating (110) is provided with a branch opening, with one end of the branch stent (200) close to the branch opening being the proximal end of the branch stent (200), and the other end being the distal end of the branch stent (200), and the branch stent (200) comprising a proximal frustum section (210) docked with the branch opening and a distal cylindrical section (220) connected to an end of the proximal frustum section (210) away from the branch opening; The proximal frustum segment (210) comprises a frustum segment coating (212) whose diameter gradually decreases from the proximal end to the distal end, and a frustum-shaped grid support (211) connected to the frustum segment coating (212) and whose diameter gradually decreases from the proximal end to the distal end; the frustum segment coating (212) is fixedly connected or integrally connected to the main body coating (110); the proximal intersection point (2111) of the frustum-shaped grid support (211) is fixedly connected to the frustum segment coating (212), and the distal intersection point (2112) of the frustum-shaped grid support (211) is separated from the frustum segment coating (212); The distal cylindrical section (220) comprises a cylindrical section coating and a multi-circle wavy stent ring fixedly connected to the cylindrical section coating.

5. The thoracic aortic stent graft according to claim 1, characterized in that: The thoracic aorta covered stent also includes an embedded stent (300); An embedded opening is provided on the main body covering (110), and the embedded opening is circular or elliptical. The embedded bracket (300) is arranged inside the main body covering (110), and comprises a hollow cylindrical section (310) and a hollow hemispherical section (320) connected to each other, and one end of the hollow hemispherical section (320) away from the hollow cylindrical section (310) is butted against the embedded opening; The hollow hemispherical body segment (320) is a hollow semicircular spherical body segment or a hollow semi-ellipsoidal spherical body segment.

6. The thoracic aorta covered stent according to claim 1, characterized in that: The main body coating (110) is also provided with a window (400).

7. The thoracic aorta covered stent according to claim 1, characterized in that: The main body coating (110) is provided with a branch structure, the branch structure comprising at least one of a branch support (200), a window (400) and an embedded support (300); The middle section of the main support frame comprises a plurality of middle wave rings (15), with the proximal end of the main coating (110) as the top end and the distal end as the bottom end: the wave troughs of each of the middle wave rings (15) are located on the same radial circumferential surface of the main coating (110), and the wave crests of each of the middle wave rings (15) at the edge of the branch structure are located on the distal side of other wave crests.

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