Covered stent and delivery system

Abstract

The invention relates to a covered stent and a delivery system, the covered stent comprises a stent body and a covered body which are connected, the proximal end of the stent body is provided with a proximal stent bare section, the proximal stent bare section protrudes outwards away from the axis, and the covered body covers the surface of the stent body. The near-end stent bare section of the covered stent can protrude outwards away from the axis to increase the anchoring property of the covered stent, and the requirement for accurate positioning in the ascending aorta is met.

Description

Technical Field

[0001] This application relates to the technical field of medical devices, and particularly to a covered stent and a delivery system. Background Art

[0002] Cardiovascular diseases pose a great threat to human health. In particular, aortic diseases, such as aortic dissection, belong to dangerous acute and severe cardiovascular diseases. Aortic dissection occurs when the inner membrane of the aortic blood vessel is damaged, causing blood to flow between the layers of the aortic wall, resulting in the symptoms of aortic dissection. Since it cannot supply enough blood to other organs, it can lead to ischemia of vital organs. Or when the aortic dissection ruptures, it can easily cause the patient to die quickly.

[0003] According to the DeBakey classification, which is widely used clinically, aortic dissection is divided into type I, type II, and type III. Among them, type I originates from the ascending aorta and involves at least the aortic arch. It is common in patients under 65 years old and has the highest mortality rate. In the acute case, the mortality rate increases by 1% per hour, accounting for 60% of all aortic dissections. Type II is only limited to the ascending aorta and is common in elderly patients with atherosclerotic diseases and hypertension, accounting for 10 - 15% of all aortic dissections. Type III originates from the descending aorta, rarely extends proximally, but may involve the distal part of the blood vessel. If the abdominal aorta is not involved, it is called type IIIA, and if the abdominal aorta is involved, it is called type IIIB, accounting for 25 - 30% of all aortic dissections.

[0004] Currently, for the treatment of aortic dissection involving the ascending aorta, emergency surgical treatment is mostly used for DeBakey type I and type II aortic dissections, and the effect is significantly better than medical conservative treatment. However, traditional surgical techniques, because they require thoracotomy, moderate hypothermic circulatory arrest, etc., there are some elderly and high-risk patients who are completely unsuitable or intolerant to surgery and may not be able to receive it.

[0005] With the development of endovascular interventional techniques, currently, in interventional treatment, a compressible stent is delivered to the lesion site in the blood vessel and then released. After the stent expands in the blood vessel, it can isolate the lesion site from the blood vessel lumen, allowing blood to pass through the stent, thereby protecting the diseased blood vessel and achieving the purpose of repairing the diseased blood vessel. However, currently, the interventional products used for aortic dissection are commonly used for the treatment of DeBakey type III dissections, and there is no mature interventional product available for the treatment of DeBakey type I and type II aortic dissections.

[0006] The ascending aorta has a complex anatomical structure, with the proximal end close to the aortic sinus, coronary artery and aortic valve, the distal end close to the innominate artery, and a short total length. However, the blood pressure is high, the blood flow is fast, and the ascending aorta has a large range of motion. Therefore, when the ascending aorta stent is anchored at the proximal end, it needs to be positioned accurately to prevent problems such as inaccurate stent positioning, displacement during stent release, and proximal bird beaks. This will cause the stent to cover the coronary artery ostium, damage the aortic valve, cover the innominate artery, leading to cerebral ischemia and stroke, and damage the blood vessel wall to cause new dissection ruptures. Summary of the invention

[0007] Based on this, it is necessary to provide a coated stent and a delivery system to address at least one of the technical problems mentioned above.

[0008] The present application provides a coated stent, which includes a connected stent body and a coated body, a proximal stent bare segment is arranged at the proximal end of the stent body, the proximal stent bare segment protrudes outward away from the axis of the stent body, and the coated body covers at least a portion of the surface of the stent body.

[0009] In one embodiment, the proximal stent bare segment at least includes a first curved bare segment and a second curved bare segment connected to each other, and the second curved bare segment is located in the proximal end direction of the first curved bare segment; wherein the first curved bare segment has a first curved arc that gradually expands radially outward from the distal end to the proximal end, and the second curved bare segment has a second curved arc that gradually retracts radially inward from the distal end to the proximal end, thereby the proximal stent bare segment bulges outward away from the axis.

[0010] In one embodiment, the connecting position of the first curved bare section and the second curved bare section is smoothly transitioned; and / or,

[0011] The radial distance of the radial outward expansion of the first curved bare section is between 2 mm and 6 mm; and / or,

[0012] The outward expansion angle of the first bending arc is between 15 degrees and 45 degrees; and / or,

[0013] The radial distance of the radial inward retraction of the second curved bare section is between 1 mm and 3 mm; and / or,

[0014] The inward angle of the second curved arc is between 5 degrees and 35 degrees.

[0015] In one embodiment, the support body comprises:

[0016] A central main frame, wherein the central main frame has a first radial supporting force;

[0017] Proximal end frame body, the proximal end frame body is located at the proximal end of the central main frame body, the proximal end frame body has a second radial supporting force, and the proximal end frame body includes the bare segment of the proximal stent;

[0018] Distal end frame body, the distal end frame body is located at the distal end of the central main frame body, and the distal end frame body has a third radial supporting force; the first radial supporting force is less than the second radial supporting force, and / or, the first radial supporting force is less than the third radial supporting force.

[0019] In one embodiment, the second radial supporting force is greater than the third radial supporting force; and / or,

[0020] The frame body diameter of the central main frame body is greater than or equal to the frame body diameter of the proximal end frame body; and / or,

[0021] The frame body diameter of the central main frame body is greater than or equal to the frame body diameter of the distal end frame body; and / or,

[0022] At least one of the proximal end frame body and the distal end frame body is provided with a developing element.

[0023] In one embodiment, the proximal end frame body includes:

[0024] Main body unit frame, the main body unit frame includes a connected distal stent main segment and the bare segment of the proximal stent;

[0025] Support unit frame, the support unit frame is connected to the main body unit frame and at least partially overlaps.

[0026] In one embodiment, the support unit frame is connected to the distal stent main segment; and / or,

[0027] The film covering body covers the surface of the frame body of the distal stent main segment; and / or,

[0028] The axial dimension of the distal stent main segment is greater than the axial dimension of the bare segment of the proximal stent.

[0029] In one embodiment, the covered stent includes:

[0030] Adjusting wire body, the proximal end of the adjusting wire body is detachably connected to the small bend side of the stent body;

[0031] Adjusting main body part, the adjusting main body part is arranged on the small bend side of the stent body, and the adjusting wire body is detachably connected to the adjusting main body part.

[0032] In one embodiment, the adjusting main body part has at least one adjusting wire hole for threading the adjusting wire body; and / or,

[0033] The adjusting main body is further configured to detachably connect to a control wire body, and the control wire body is configured to lock or release the connection between the adjusting wire body and the adjusting main body; and / or,

[0034] At least two of the adjusting wire bodies and at least two of the adjusting main bodies are provided on the support body, and each of the adjusting wire bodies is detachably connected to at least one of the adjusting main bodies; and / or,

[0035] The adjusting main body is located in the proximal region of the support body; and / or,

[0036] An auxiliary adjusting member is provided on the support body, and the auxiliary adjusting member is located in the distal direction of the adjusting main body and is configured to at least define the extending trajectory of the adjusting wire body.

[0037] In one embodiment, at least one binding wire body is provided on the support body for binding the support body to a contracted state; and / or,

[0038] A wrapping film body is provided on the support body, and the wrapping film body is connected to the support body for circumferentially wrapping the support body.

[0039] In one embodiment, at least one set of binding connectors is provided on the support body, and each set of the binding connectors is arranged along the circumference of the support body. Each of the binding wire bodies is configured to be connected to at least one set of the binding connectors along the circumference of the support body, so as to bind the support body to a contracted state; and / or,

[0040] A wrapping connection part is provided on the wrapping film body, and the wrapping connection part is configured to detachably connect to a wrapping release wire body.

[0041] The present application provides a delivery system for delivering the covered stent, and the delivery system includes:

[0042] Inner core tube;

[0043] Outer sheath tube, the outer sheath tube has an axially penetrating sheath lumen, the outer sheath tube is movably sleeved outside the inner core tube, and a converging shaft cavity is formed between the inner wall of the outer sheath tube and the outer wall of the inner core tube, and the converging shaft cavity is used for assembling the covered stent.

[0044] In one embodiment, the delivery system includes:

[0045] A stent release wire body, the stent release wire body movably penetrates through the converging shaft cavity, and the proximal end of the stent release wire body is configured to detachably connect the proximal end of the covered stent to the proximal end of the inner core tube; and / or,

[0046] A delivery guiding wire body, the inner core tube has an axially penetrating core tube inner cavity, and the delivery guiding wire body is movably disposed in the core tube inner cavity; and / or,

[0047] A proximal guiding component, the proximal guiding component is disposed at the proximal end of the inner core tube.

[0048] It can be understood that in some other embodiments, the delivery system in the present application may further include at least one of the foregoing components such as an adjustment wire body, an adjustment main body member, an auxiliary adjustment member, and a control wire body.

[0049] For the above-mentioned covered stent and delivery system, the proximal stent bare segment of the covered stent can be attached and anchored to the healthy sinus tube junction, and the anchoring property of the covered stent is increased by protruding outward from the axis, preventing the covered stent from shifting due to blood flow or other reasons, and meeting the requirement of accurate positioning in the ascending aorta during the operation. Description of the Drawings

[0050] Figure 1 It is a schematic diagram of the usage state of a covered stent provided by an embodiment of the present application.

[0051] Figure 2 It is a schematic diagram of the structure of a covered stent provided by an embodiment of the present application.

[0052] Figure 3 It is a schematic diagram of the structure of a main unit frame provided by an embodiment of the present application.

[0053] Figure 4 It is a schematic diagram of the usage state of an adjustment wire body provided by an embodiment of the present application.

[0054] Figure 5 It is an assembly schematic diagram of a binding connection body provided by an embodiment of the present application.

[0055] Figure 6 It is a schematic diagram of the contracted state of a covered stent provided by an embodiment of the present application.

[0056] Figure 7 It is a schematic diagram of the structure of a covered stent wrapped by a wrapping membrane body provided by an embodiment of the present application.

[0057] Reference Numerals in the Drawings:

[0058] 10. Ascending aorta; 20. Coronary artery orifice; 30. Innominate artery;

[0059] 100. Stent release wire body;

[0060] 1000. Stent body; 2000. Covering membrane body; 3000. Imaging element; 4000. Adjustment wire body; 5000. Binding wire body; 6000. Wrapping membrane body;

[0061] 1100, central main frame; 1200, proximal end frame; 1300, distal end frame;

[0062] 1210, main unit frame; 1220, support unit frame;

[0063] 1211, distal stent main section; 1212, proximal stent bare section; 1212a, first curved bare section; 1212b, second curved bare section;

[0064] 4100, adjusting main body; 4100a, adjusting wire hole; 4200, control wire body; 4300, auxiliary adjusting member; 5100, restraining connector; 6100, wrapping connector; 6200, wrapping release wire body. DETAILED DESCRIPTION

[0065] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0066] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0067] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0068] In this application, unless otherwise clearly defined and limited, if terms such as "installed", "connected", "linked", "fixed", etc. appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0069] In this application, unless otherwise clearly defined and limited, if there is a description such as a first feature being "on" or "under" a second feature, its meaning can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over", and "on top of" the second feature can be that the first feature is directly above or obliquely above the second feature, or simply means that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath", and "underneath" the second feature can be that the first feature is directly below or obliquely below the second feature, or simply means that the first feature has a lower horizontal height than the second feature.

[0070] It should be noted that if an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there can also be an intermediate element. If an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. If so, the terms "vertical", "horizontal", "up", "down", "left", "right", and similar expressions used in this application are only for the purpose of illustration and do not represent the only implementation.

[0071] Refer to Figures 1 to 3 As shown, an embodiment of this application provides a covered stent. The covered stent includes a stent body 1000 and a covering body 2000. The stent body 1000 has a contracted state and a deployed state. In the contracted state, it has a smaller volume and can be bundled in a delivery system. In the deployed state, it has a larger volume and can be used to maintain in a blood vessel in a living body. The stent body 1000 can be a cylindrical structure with both ends penetrating, as long as it is suitable for being implanted into a blood vessel in a living body. The stent body 1000 can be made of superelastic and shape-memory metal woven or cut, such as nickel-titanium alloy. This application does not limit the specific structure, size, material, etc. of the stent body 1000, and those skilled in the art can design according to actual usage requirements.

[0072] The film covering body 2000 can be made of polyethylene terephthalate (PET) material. The film covering body 2000 and the stent body 1000 can be sewn together through stent sutures. The film covering body 2000 can also use polytetrafluoroethylene (PTFE) material and be combined with the stent body 1000 by hot melting. The covered stent can separate the true lumen of the ascending aorta 10 from the false lumen through the film covering body 2000, achieving the purpose of blocking the proximal dissection tear. Refer to Figure 1 As shown, the covered stent can be inserted through the femoral artery approach and released along the aortic arch into the ascending aorta 10 to block the proximal dissection tear of the ascending aorta 10. The proximal end of the covered stent is anchored at the sinus-tube junction and does not cover the coronary artery ostium 20, and the distal end does not cover the brachiocephalic artery 30.

[0073] Refer to Figure 2 As shown, the stent body 1000 can be at least divided into three parts: the central main stent body 1100, the proximal stent body 1200, and the distal stent body 1300. To more clearly describe the structure of the covered stent and the delivery system, the term "distal end" is defined here as the end far from the heart during the operation, and the term "proximal end" is defined as the end close to the heart during the operation. Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0074] The central main stent body 1100, the proximal stent body 1200, or the distal stent body 1300 can adopt various structures and shapes. For example Figure 2 As shown, the central main stent body 1100, the proximal stent body 1200, or the distal stent body 1300 can be constructed into an annular ring with a curved structure according to design requirements. The annular ring can generally present various curved structures such as a V shape or a wavy shape. At least one annular ring can be included in the central main stent body 1100, the proximal stent body 1200, or the distal stent body 1300 according to their respective needs, and the annular rings in the central main stent body 1100, the proximal stent body 1200, or the distal stent body 1300 can have the same or different sizes, shapes, materials, etc. For example Figure 2 As shown, the central main stent body 1100 can include four annular rings, and the proximal stent body 1200 or the distal stent body 1300 can include one or two annular rings. For example Figure 2 As shown, in one embodiment, the proximal stent body 1200 can include a main body unit stent 1210 and a support unit stent 1220, forming a double-stent structure. The meaning of the double-stent structure is that a whole is jointly formed by the main body unit stent 1210 and the support unit stent 1220. At least a part of the main body unit stent 1210 and the support unit stent 1220 can be as Figure 2The above is kept coincident. Those skilled in the art can design the number, size, type, material, connection method, etc. of the annular rings in the stent body 1000 according to actual needs, so as to construct a stent body 1000 suitable for surgical requirements, which is not limited here.

[0075] Continue to refer to Figures 1 to 3 As shown, the proximal end of the stent body 1000 has a proximal stent bare segment 1212. The proximal stent bare segment 1212 can be located in the main body unit frame 1210 and the proximal end frame body 1200 in different embodiments, that is, the proximal stent bare segment 1212 is always located at the proximal end of the stent body 1000. The proximal stent bare segment 1212 can at least include a connected first bent bare segment 1212a and a second bent bare segment 1212b, so that the proximal stent bare segment 1212 has at least two bending arcs with direction changes in the direction from the distal end to the proximal end. For example, the second bent bare segment 1212b is located in the proximal end direction of the first bent bare segment 1212a. The first bent bare segment 1212a has a first bending arc that gradually expands radially outward in the direction from the distal end to the proximal end, and the second bent bare segment 1212b has a second bending arc that gradually converges radially inward in the direction from the distal end to the proximal end. In addition, the second bent bare segment 1212b can also be in a parallel state, etc. in the direction from the distal end to the proximal end.

[0076] Combined with Figure 2 and Figure 3 It can be known that when the membrane body 2000 is connected to the stent body 1000 and covers the surface of the frame body of the stent body 1000, the proximal stent bare segment 1212 in the stent body 1000 can be exposed outside the membrane body 2000. Since the proximal stent bare segment 1212 at least includes a first bent bare segment 1212a and a second bent bare segment 1212b with bending arcs, and in the direction from the distal end to the proximal end, the proximal stent bare segment 1212 first expands radially outward and then converges radially inward, the covered stent can form good anchoring with the blood vessel wall through the proximal stent bare segment 1212 exposed outside the membrane body 2000, and at the same time can prevent damage to the blood vessel. Refer to Figure 1 As shown, after the covered stent is implanted into the ascending aorta 10, the proximal stent bare segment 1212 of the covered stent can be attached to and anchored at the healthy sinus-tubular junction. The cardiac aortic sinus-tubular junction is located on the left side of the left atrium of the heart, above the aortic valve. The radial outward expansion of the first bent bare segment 1212a can increase the anchoring of the covered stent and prevent the covered stent from shifting due to blood flow and other reasons. The operator can increase the anchoring with the help of the proximal stent bare segment 1212 according to actual surgical needs to meet the requirement of accurate positioning in the ascending aorta 10 during the operation. And the radial inward convergence of the second bent bare segment 1212b also prevents the covered stent from damaging the blood vessel and ensures the safety of the operation.

[0077] The first curved bare segment 1212a and the second curved bare segment 1212b can be integrally formed. In short, it is necessary to make the connection position between the first curved bare segment 1212a and the second curved bare segment 1212b have a smooth transition, and reduce the damage to blood vessels through the smooth outer wall. When the proximal frame 1200 is constructed with a curved structure such as a substantially V-shaped or wavy shape, the first curved bare segment 1212a and the second curved bare segment 1212b that constitute the proximal stent bare segment 1212 can belong to the tip of the V shape (i.e., the A-shaped tip) in the annular ring. At this time, the proximal stent bare segment 1212 can be formed by connecting the heads and tails of 5 to 7 V-shaped edges in the circumferential direction. For example, it includes 6 V-shaped edges, so that the proximal stent bare segment 1212 has a certain radial support force. Among them, the axial length of the proximal frame 1200 can be controlled between 20 mm and 25 mm, so that the exposed proximal stent bare segment 1212 can be longer, avoiding the problem that the proximal end of the covered stent turns over during the release process due to the too short exposed proximal stent bare segment 1212.

[0078] The vertex of each V-shaped edge in the proximal frame 1200 can adopt an arc design, and the arc diameter of the vertex of the V-shaped edge can be controlled between 2.5 mm and 3.5 mm to prevent the covered stent from damaging blood vessels and avoid causing new dissection openings. In the proximal frame 1200, about 3 / 4 of the axial length can be sewn and stored inside the covering body 2000, and the remaining about 1 / 4 of the axial length is exposed outside the covering body 2000, and the exposed axial length can be controlled at about 4 mm to 6 mm. This size of the exposed design can prevent the covered stent from covering the coronary blood vessels to a certain extent and avoid poor coronary blood vessel perfusion.

[0079] The radially expanding radial distance of the first curved bare segment 1212a can be controlled between 2 mm and 6 mm. Radially expanding refers to the expansion in the radial direction, and the radially expanding radial distance refers to the increase in size in the radial direction. For example, the radially expanding radial distance of the first curved bare segment 1212a is 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, etc. The expansion angle of the first curved arc (referring to the angle of the first curved arc expanding in the radial direction) can be controlled between 15 degrees and 45 degrees. For example, the expansion angle of the first curved arc is 15 degrees, 20 degrees, 25 degrees, 30 degrees, 35 degrees, 40 degrees, 45 degrees, etc. By reasonably controlling the radially expanding radial distance of the first curved bare segment 1212a and the expansion angle of the first curved arc, the safety and anchoring performance of the first curved bare segment 1212a can be ensured. Avoiding too large radial distance and expansion angle to prevent the first curved bare segment 1212a from puncturing the blood vessel and causing blood vessel damage, and avoiding too small radial distance and expansion angle to prevent poor anchoring performance of the first curved bare segment 1212a and unexpected displacement.

[0080] The radially inward distance of the second bent bare segment 1212b can be controlled between 1 mm and 3 mm. Radially inward refers to inward movement in the radial direction, and the radially inward distance refers to the reduction in size in the radial direction. For example, the radially inward distance of the second bent bare segment 1212b is 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, etc. The inward angle of the second bent arc (referring to the angle at which the diameter of the second bent arc moves radially inward) can be controlled between 5 degrees and 35 degrees. For example, the inward angle of the second bent arc is 5 degrees, 10 degrees, 15 degrees, 20 degrees, 25 degrees, 30 degrees, etc. Those skilled in the art can design the specific forms of the first bent bare segment 1212a and the second bent bare segment 1212b according to actual needs, which are not limited herein.

[0081] Continue to refer to Figure 2 As shown, in one embodiment, the proximal frame 1200 may include a main unit frame 1210 and a support unit frame 1220. The main unit frame 1210 and the support unit frame 1220 constitute the proximal frame 1200 with a double-frame structure. The meaning of the double-frame structure is that the main unit frame 1210 and the support unit frame 1220 together form a whole, and at least a part of the main unit frame 1210 and the support unit frame 1220 may Figure 2 be kept coincident as shown. Among them, the main unit frame 1210 may have a fourth radial supporting force, and the support unit frame 1220 has a fifth radial supporting force. Since the main unit frame 1210 and the support unit frame 1220 constitute a double-frame structure, after adding the support unit frame 1220 to the main unit frame 1210, the radial supporting force of the double-frame structure can be improved. Among them, the fifth radial supporting force of the support unit frame 1220 can be adjusted according to actual needs. For example, it can be less than, greater than, or equal to the fourth radial supporting force of the main unit frame 1210, which is not limited herein. The main unit frame 1210 serves as the main structure of the proximal frame 1200, and its proximal end can form the proximal stent bare segment 1212. And the support unit frame 1220 with a more superior radial supporting force can be attached to the main unit frame 1210 to improve the radial supporting force of the entire proximal frame 1200. The radial supporting force refers to the magnitude of the ability to withstand the supporting force in the radial direction and can be measured by a crimping machine.

[0082] The advantage of the double-frame structure is that the main unit frame 1210 does not need to be designed with a large radial supporting force to ensure that parts such as the exposed proximal stent bare segment 1212 do not damage the blood vessel. After attaching the support unit frame 1220 at an appropriate position of the main unit frame 1210, the support unit frame 1220 can be used to improve the radial supporting force at the corresponding position of the main unit frame 1210, thereby improving the radial supporting and radial sealing effects of the proximal end of the covered stent and preventing proximal end endoleakage. Refer to Figure 3As shown, the main body unit frame 1210 may include a connected distal stent main section 1211 and a proximal stent bare section 1212. Among them, the distal stent main section 1211 may be covered by the film body 2000, while the proximal stent bare section 1212 is not covered by the film body 2000. The support unit frame 1220 (which can be covered by the film body 2000) is connected to the distal stent main section 1211, and the support unit frame 1220 is used to increase the radial support force of the distal stent main section 1211 in the main body unit frame 1210. At this time, the film body 2000 may cover the frame surface of the distal stent main section 1211. The distal stent main section 1211 of the main body unit frame 1210 and the support unit frame 1220 are on both sides of the film body 200, one of them is on the inner side of the film body 200 and the other is on the outer side of the film body 200, and the two are kept at the same height position. The axial dimension of the distal stent main section 1211 may be greater than the axial dimension of the proximal stent bare section 1212. The axial dimension is the axial length.

[0083] All in all, the double-frame structure reasonably distributes the radial support force distribution of the proximal end frame 1200, while meeting the requirements of sealing support and safety. Among them, the proximal end frame 1200 can be sutured on the film body 2000 to provide a certain support force to prevent proximal end endoleakage of the covered stent. The main body unit frame 1210 and the support unit frame 1220 can be constructed with different radial support forces in terms of different structures, shapes, sizes, materials, etc. For example, refer to Figure 2 As shown, the main body unit frame 1210 and the support unit frame 1220 are also constructed by annular rings. Among them, the number of V-shaped edges included in one week of the main body unit frame 1210 may be less than the number of V-shaped edges included in one week of the support unit frame 1220. For example, the difference in their numbers may be twice, etc. Different radial support forces are built through the difference in the number of V-shaped edges included in one week.

[0084] The central main frame 1100 and the distal end frame 1300 may also adopt a structure and shape similar to that of the proximal end frame 1200. Refer to Figure 2As shown, the central main frame 1100 can adopt an annular ring with an axial length between 12 mm and 18 mm and the number of V-shaped ribs between 8 and 12. Approximately 1 / 2 to 2 / 3 of the central main frame 1100 can be sutured onto the film body 2000 to provide good flexibility of the film-covered stent, provide the ability to resist stretching, thereby enabling the film-covered stent to better conform to the anatomical structure of the ascending aorta 10 and prevent the displacement of the film-covered stent. The distal frame 1300 adopts an annular ring with an axial length between 15 mm and 20 mm and the number of V-shaped ribs between 7 and 9. The distal frame 1300 is sutured onto the film body 2000 to provide a certain supporting force and prevent distal end endoleakage of the film-covered stent. At this time, the vertex of each V-shaped rib in the distal frame 1300 can also adopt an arc design, and the arc diameter of the vertex of the V-shaped rib can be controlled between 2.5 mm and 3.5 mm to prevent the film-covered stent from damaging the blood vessel and avoid causing new dissection ruptures.

[0085] In one embodiment, the central main frame 1100 has a first radial supporting force, the proximal frame 1200 has a second radial supporting force, and the distal frame 1300 has a third radial supporting force, and the first radial supporting force can be controlled to be less than at least one of the second radial supporting force and the third radial supporting force. For example, the first radial supporting force is less than the second radial supporting force and the third radial supporting force, and the second radial supporting force is greater than the third radial supporting force.

[0086] The proximal frame 1200 has the strongest radial supporting force, which can meet the functions of proximal end anchoring, anti-displacement, and anti-proximal end endoleakage of the film-covered stent. The central main frame 1100 has the weakest radial supporting force, which can meet the requirements of flexibility, fatigue resistance, and small damage to blood vessel compliance of the film-covered stent. The distal frame 1300 has a medium supporting force, which can balance the requirements of distal end endoleakage prevention, anti-displacement, fatigue resistance, and small damage to blood vessel compliance of the film-covered stent.

[0087] Since the anatomical structure of the ascending aorta 10 shows that the blood vessel diameters at the proximal end and the distal end are similar, and the blood vessel diameter in the middle section is slightly larger. To conform to the anatomical structure of the ascending aorta 10, the frame diameter of the central main frame 1100 can be designed to be greater than or equal to the frame diameter of at least one of the proximal frame 1200 and the distal frame 1300, and the frame diameters of the proximal frame 1200 and the distal frame 1300 can be designed similarly.

[0088] At least one of the proximal end frame 1200 and the distal end frame 1300 is provided with a developing element 3000, and the developing element 3000 can be located at the proximal end of the proximal end frame 1200 or the distal end of the distal end frame 1300. This facilitates the evaluation and adjustment of the release position of the covered stent before and after the release process, and avoids covering the coronary artery and the innominate artery 30. The developing element 3000 can be selected in the structure of developing points and developing rings.

[0089] Referring to Figure 4 As shown, the covered stent includes an adjustment wire body 4000, and the proximal end of the adjustment wire body 4000 is detachably connected to the minor curve side of the stent body 1000. The minor curve side refers to the side of the stent that faces away from the branch vessels on the arch after the stent is implanted into the organism, and the major curve side refers to the side of the stent that faces the branch vessels on the arch after the stent is implanted into the organism. Among them, the proximal end of the adjustment wire body 4000 can be selectively connected to an appropriate position such as the proximal end frame 1200 of the stent body 1000 or the proximal end region of the central main frame 1100. When the covered stent is fully released, if the fit between the proximal end of the covered stent and the blood vessel is not good, for example, causing the beak phenomenon, the operator can first determine the position where the beak phenomenon occurs, and then pull the proximal end of the covered stent by pulling the adjustment wire body 4000 to adjust the fit form of the covered stent, eliminate the beak phenomenon, and solve the problem of proximal end endoleakage.

[0090] The proximal end of the adjustment wire body 4000 can be detachably connected to the minor curve side of the stent body 1000 in various ways by direct connection or indirect connection. For example, in one embodiment, the covered stent may include an adjustment main body 4100, and the adjustment main body 4100 is arranged on the minor curve side of the stent body 1000. After the pulling position is determined on the covered stent in advance by the adjustment main body 4100, the operator can detachably connect the adjustment wire body 4000 to the adjustment main body 4100. In one embodiment, the adjustment main body 4100 may have at least one adjustment wire hole 4100a, and the adjustment wire body 4000 can be connected to the adjustment main body 4100 by threading through the adjustment wire hole 4100a and using methods such as tying and bonding.

[0091] In addition, the covered stent may include a control wire body 4200. The adjustment main body 4100 is also used for detachably connecting the control wire body 4200. The control wire body 4200 is used to lock the connection between the adjustment wire body 4000 and the adjustment main body 4100. That is, when the control wire body 4200 locks the connection between the adjustment wire body 4000 and the adjustment main body 4100, a surgeon pulling the adjustment wire body 4000 alone cannot achieve the separation between the adjustment wire body 4000 and the adjustment main body 4100. The control wire body 4200 is also used to release the connection between the adjustment wire body 4000 and the adjustment main body 4100. That is, only after the control wire body 4200 releases the connection between the adjustment wire body 4000 and the adjustment main body 4100 can a surgeon pulling the adjustment wire body 4000 achieve the separation between the adjustment wire body 4000 and the adjustment main body 4100. Therefore, the control wire body 4200 effectively prevents a surgeon from wrongly pulling the adjustment wire body 4000.

[0092] Refer to Figure 4 As shown, the adjustment main body 4100 may have at least two adjustment wire holes 4100a, such that both the adjustment wire body 4000 and the control wire body 4200 can be threaded through different adjustment wire holes 4100a of the same adjustment main body. For example, the adjustment main body 4100 forms a structure similar to an 8 shape by opening two adjustment wire holes 4100a. The adjustment wire body 4000 can pass through one of the adjustment wire holes 4100a, and the control wire body 4200 can pass through the other adjustment wire hole 4100a. A surgeon can use the proximal end of the control wire body 4200 to fix the proximal end of the adjustment wire body 4000 in the adjustment wire hole 4100a it passes through by means of tying or bonding.

[0093] At least two adjustment wire bodies 4000 and at least two adjustment main bodies 4100 may be provided on the stent body 1000, and each adjustment wire body 4000 is detachably connected to at least one adjustment main body 4100. The at least two adjustment main bodies 4100 may be arranged substantially symmetrically along the circumferential direction of the stent body 1000, and the circumferential angle between adjacent adjustment main bodies 4100 may be controlled between 60 degrees and 150 degrees, which is beneficial for treating ascending aortic stent patients with large-angle bending and torsion. The circumferential angle means that the adjustment main body 4100 has a perpendicular line with the central axis of the stent body 1000, and the included angle between two perpendicular lines formed by adjacent adjustment main bodies 4100. The adjustment main body 4100 may be located in the proximal end region of the stent body 1000, and an auxiliary adjustment member 4300 may also be provided on the stent body 1000 and be located in the distal end direction of the adjustment main body 4100.

[0094] The adjusting main body 4100 and the auxiliary adjusting member 4300 can be arranged on the stent body 1000 by means such as suturing. After the suturing is completed, the stent body 1000 can be compressed, and through the method of heat treatment setting, good flexibility and anti-stretching ability can be constructed. In the direction from the distal end to the proximal end, the adjusting wire body 4000 and the control wire body 4200 can first pass through the holes opened in the auxiliary adjusting member 4300 movably. Then it extends in the direction of the proximal end and is connected to the adjusting main body 4100. The auxiliary adjusting member 4300 can help the adjusting wire body 4000 and the control wire body 4200 extend along the axial direction of the stent body 1000.

[0095] Refer to Figure 5 and Figure 6 As shown, in one embodiment, at least one binding wire body 5000 is arranged on the stent body 1000, and the binding wire body 5000 is connected to the stent body 1000. The operator can use the binding wire body 5000 to wind around the stent body 1000 circumferentially, and then bind the stent body 1000 to the contracted state. Among them, as Figure 5 shown, at least one group of binding connectors 5100 can be arranged on the stent body 1000. Each group of binding connectors 5100 is arranged along the circumferential direction of the stent body 1000. Among them, after multiple groups of binding connectors 5100 are arranged along the circumferential direction of the stent body 1000, adjacent binding connectors 5100 will be formed, and such adjacent binding connectors 5100 are all parallel to each other. Each binding wire body 5000 can be connected to at least one group of binding connectors 5100 along the circumferential direction of the stent body 1000. For example Figure 6 shown, when multiple binding wire bodies 5000 wind and bundle the stent body 1000 circumferentially at different axial positions of the stent body 1000, the stent body 1000 can be bound to the contracted state. Refer to Figure 5 shown, the binding connector 5100 can adopt a structure such as a ring or a circle that can pass through the binding wire body 5000 movably, or at least has a hole that can pass through the binding wire body 5000 movably. The binding connectors 5100 can be distributed at intervals on the same or different V-shaped edges, which is not limited here.

[0096] Refer to Figure 2 and Figure 7As shown, a wrapping film body 6000 may also be provided on the stent body 1000, and the wrapping film body 6000 is connected to the stent body 1000. The operator can use the wrapping film body 6000 to wrap the stent body 1000 along the circumferential direction of the stent body 1000. In one embodiment, a wrapping connection part 6100 may be provided on the wrapping film body 6000, and the wrapping connection part 6100 is used to detachably connect the wrapping release wire body 6200. For example, the wrapping connection part 6100 also adopts a hole structure or other circular ring or circular structures opened on the wrapping film body 6000, so that after the wrapping film body 6000 circumferentially wraps the stent body 1000 in a contracted state, the wrapping release wire body 6200 can also pass through the wrapping connection part 6100 to fix the wrapped state of the wrapping film body 6000 wrapping the stent body 1000.

[0097] The wrapping film body 6000 can be connected to the covered film body 2000 by means of suturing, bonding, etc. The length of the wrapping film body 6000 can be the same as the length of the covered film body 2000, that is, the axial dimension of the wrapping film body 6000 can be the same as the axial dimension of the covered film body 2000. After the stent body 1000 is constricted into a contracted state by the binding wire body 5000, the operator can use the wrapping film body 6000 to cover and bind the outer layer of the stent body 1000, which is convenient for adjusting the position of the stent body 1000 before and after release and preventing the stent body 1000 from damaging blood vessels. The operator can release the connection between the wrapping connection part 6100 and the stent body 1000 by pulling the wrapping release wire body 6200 to control the unfolding of the wrapping film body 6000 relative to the stent body 1000. The wrapping film body 6000 can also be restricted by a fixed coil provided on the delivery system at the distal end to prevent the stent body 1000 from moving during the operation before the wrapping film body 6000 is released.

[0098] The present application provides a delivery system for delivering a covered stent. The delivery system includes an inner core tube and an outer sheath tube. The outer sheath tube has an axially penetrating sheath lumen. The outer sheath tube is movably sleeved outside the inner core tube. A constriction shaft cavity is formed between the inner wall of the outer sheath tube and the outer wall of the inner core tube. The constriction shaft cavity is used to assemble the covered stent and constrict the covered stent into a contracted state. Refer to Figure 1 As shown, the delivery system can enter from the femoral artery and release the covered stent into the ascending aorta 10 along the aortic arch, and use the covered stent to block the proximal ascending aorta 10 dissection rupture opening. The proximal end of the covered stent is anchored at the sinus-tube junction and does not cover the coronary artery orifice 20, and the distal end does not cover the brachiocephalic artery 30.

[0099] The delivery system further includes a stent release wire body 100, a delivery guide wire body (not shown), or a proximal guide member (not shown). The stent release wire body 100 is movably disposed through the convergence shaft cavity. The proximal end of the stent release wire body 100 is used to detachably connect the proximal end of the covered stent to the proximal end of the inner core tube. The inner core tube has an axially through core tube inner cavity, and the delivery guide wire body is movably disposed through the core tube inner cavity. The proximal guide member is disposed at the proximal end of the inner core tube. The proximal end of the stent release wire body 100 can fix the proximal end of the covered stent to the proximal guide member of the delivery system along the large bend side of the proximal stent bare segment 1212, preventing the problem of inaccurate proximal end positioning caused by the movement of the proximal end of the covered stent during the release process of the covered stent.

[0100] In addition, in some other embodiments, the delivery system in the present application may further include at least one of the aforementioned components such as an adjustment wire body, an adjustment main body member, an auxiliary adjustment member, and a control wire body. The present application does not make specific limitations thereto.

[0101] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0102] The above-described embodiments merely represent several implementation manners of the present application, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A stent graft, It is characterized in that The coated stent comprises a connected stent body and a coated body, a proximal stent bare segment is arranged at the proximal end of the stent body, the proximal stent bare segment protrudes outward away from the axis of the stent body, and the coated body covers at least a portion of the surface of the stent body.

2. The stent graft according to claim 1, It is characterized in that The bare segment of the proximal stent includes at least a first curved bare segment and a second curved bare segment connected to each other, and the second curved bare segment is located in the proximal end direction of the first curved bare segment; wherein, the first curved bare segment has a first curved arc that gradually expands radially outward from the distal end to the proximal end, and the second curved bare segment has a second curved arc that gradually retracts radially inward from the distal end to the proximal end, thereby the bare segment of the proximal stent bulges outward away from the axis.

3. The stent graft according to claim 2, It is characterized in that The connecting position of the first curved bare section and the second curved bare section is smoothly transitioned; and / or, The radial distance of the radial outward expansion of the first curved bare section is between 2 mm and 6 mm; and / or, The outward expansion angle of the first bending arc is between 15 degrees and 45 degrees; and / or, The radial distance of the radial inward retraction of the second curved bare section is between 1 mm and 3 mm; and / or, The inward angle of the second curved arc is between 5 degrees and 35 degrees.

4. The stent graft according to claim 2, It is characterized in that The support body comprises: A central main frame, wherein the central main frame has a first radial supporting force; A proximal end frame body, the proximal end frame body is located at the proximal end of the central main frame body, the proximal end frame body has a second radial support force, and the proximal end frame body includes the proximal stent bare segment; A distal end frame, the distal end frame is located at the distal end of the central main frame, and the distal end frame has a third radial supporting force; the first radial supporting force is smaller than the second radial supporting force, and / or the first radial supporting force is smaller than the third radial supporting force.

5. The stent graft according to claim 4, It is characterized in that The second radial supporting force is greater than the third radial supporting force; and / or, The diameter of the central main frame is greater than or equal to the diameter of the proximal frame; and / or, The diameter of the central main frame is greater than or equal to the diameter of the distal end frame; and / or, At least one of the proximal end frame and the distal end frame is provided with a developing element.

6. The stent graft according to claim 4, It is characterized in that The proximal end frame comprises: A main unit frame, the main unit frame comprising a connected distal stent main segment and the proximal stent bare segment; A supporting unit frame is connected to the main unit frame and at least a portion of the supporting unit frame overlaps with the main unit frame.

7. The stent graft according to claim 6, It is characterized in that The support unit frame is connected to the distal stent main section; and / or, The coating body covers the surface of the distal stent main segment; and / or, The axial dimension of the distal stent main segment is greater than the axial dimension of the proximal stent bare segment.

8. The stent graft according to claim 1, It is characterized in that the covered stent includes: an adjusting wire body, the proximal end of the adjusting wire body is detachably connected to the minor curvature side of the stent body; an adjusting main body member, the adjusting main body member is arranged on the minor curvature side of the stent body, and the adjusting wire body is detachably connected to the adjusting main body member.

9. The covered stent according to claim 8, It is characterized in that the adjusting main body member has at least one adjusting wire hole for threading the adjusting wire body; and / or, the adjusting main body member is further used for detachably connecting a control wire body, and the control wire body is used for locking or releasing the connection between the adjusting wire body and the adjusting main body member; and / or, at least two of the adjusting wire bodies and at least two of the adjusting main body members are arranged on the stent body, and each adjusting wire body is detachably connected to at least one adjusting main body member; and / or, the adjusting main body member is located in the proximal region of the stent body; and / or, an auxiliary adjusting member is arranged on the stent body, and the auxiliary adjusting member is located in the distal direction of the adjusting main body member for at least defining the extending trajectory of the adjusting wire body.

10. The covered stent according to claim 1, It is characterized in that at least one binding wire body is arranged on the stent body for binding the stent body to a contracted state; and / or, a wrapping film body is arranged on the stent body, and the wrapping film body is connected to the stent body for circumferentially wrapping the stent body.

11. The covered stent according to claim 10, It is characterized in that at least one group of binding connecting bodies is arranged on the stent body, and each group of binding connecting bodies is arranged along the circumference of the stent body, and each binding wire body is used for connecting to at least one group of binding connecting bodies along the circumference of the stent body, so as to bind the stent body to a contracted state; and / or, a wrapping connecting part is arranged on the wrapping film body, and the wrapping connecting part is used for detachably connecting a wrapping release wire body.

12. A delivery system, It is characterized in that for delivering the covered stent according to any one of claims 1-11, and the delivery system includes: an inner core tube; an outer sheath tube, the outer sheath tube has an axially penetrating sheath tube lumen, the outer sheath tube is movably sleeved outside the inner core tube, and a converging shaft cavity is formed between the inner wall of the outer sheath tube and the outer wall of the inner core tube for assembling the covered stent.

13. The delivery system according to claim 12, It is characterized in that the delivery system includes: a stent release wire body, the stent release wire body movably penetrates through the converging shaft cavity, and the proximal end of the stent release wire body is used for detachably connecting the proximal end of the covered stent to the proximal end of the inner core tube; and / or, a delivery guiding wire body, the inner core tube has an axially penetrating core tube lumen, and the delivery guiding wire body movably penetrates through the core tube lumen; and / or, a proximal guiding component, the proximal guiding component is arranged at the proximal end of the inner core tube.

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