Luminal stent

Abstract

The present invention discloses a lumen stent, which includes a tube body and a skirt connected to the tube body. At least one anchoring portion is provided on the skirt in the circumferential direction. When there are multiple anchoring portions on the skirt, the multiple anchoring portions are arranged at intervals. When only one anchoring portion is provided on the skirt, the anchoring portion surrounds a part of the skirt in the circumferential direction. After the above lumen stent is implanted into the main body covered stent, the skirt can block the gap between the above lumen stent and the fenestration area on the main body stent, and the anchoring portion is used to anchor the lumen stent; when multiple above lumen stents are implanted and the distance between the lumen stents is relatively close, since a single anchoring portion only surrounds a part of the skirt in the circumferential direction, or multiple anchoring portions are arranged at intervals in the circumferential direction, therefore, the anchoring portions of adjacent lumen stents can be staggeredly placed, so as to avoid the situation of poor blocking effect caused by overlap or mutual extrusion deformation between adjacent lumen stents.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and particularly to a lumen stent. Background Art

[0002] In the past decade or so, endovascular aortic aneurysm repair (EVAR) has been widely used in the treatment of aortic aneurysms, aortic dissections and other lesions in the thoracic and abdominal aorta. It has the advantages of definite curative effect, minimal trauma, quick recovery and few complications, and has become the first-line treatment method. However, for special lesion sites such as the aortic arch, celiac trunk, bilateral renal arteries or superior mesenteric artery, the use of a covered stent will affect the blood supply of the arterial branch vessels. In response to this situation, the main body covered stent is often fenestrated in situ by laser or mechanical means during the operation to produce the expected holes in the main body covered stent, and then the branch stent is delivered to the hole to dock with the main body covered stent. This treatment plan overcomes the dependence on the anatomical structure of the human branch vessels. At present, straight tube covered stents are basically selected as the branch stents in the fenestration method. However, due to the gap between the fenestration area and the branch stent, type III endoleak is likely to occur, which may lead to the failure of the operation. As Figure 1 shown, the blood in the aorta will flow into the aortic dissection 1 through the gap between the branch stent 10 and the fenestration area of the main body stent 20, resulting in type III endoleak.

[0003] Currently, a skirted covered stent is mainly used to replace the straight tube covered stent to solve the above problems. The skirted covered stent is to add a skirt on the basis of the straight tube covered stent. As Figure 2 shown, when the skirted covered stent is implanted as the branch stent 10 into the main body stent 20, the skirts 11a and 11b turn outwards to anchor the branch stent 10 and block the gap between the branch stent 10 and the fenestration area on the main body stent 20 to prevent type III endoleak. However, when multiple branch stents 10 are implanted and the distance between the branch stents 10 is relatively close, the outwards turned skirts 11a and 11b of the adjacent branch stents 10a and 10b may overlap or be squeezed and deformed, thereby resulting in poor sealing effect on the gap between the branch stents 10a and 10b and the fenestration area of the main body stent 20. Summary of the Invention

[0004] Based on this, it is necessary to provide a lumen stent to avoid the problem of poor sealing effect caused by the overlap or mutual extrusion and deformation of the outwards turned skirts between adjacent stents.

[0005] The present invention provides a lumen stent, including a tube body and a skirt connected to the tube body. At least one anchoring portion is provided on the skirt in the circumferential direction. When there are multiple anchoring portions on the skirt, the multiple anchoring portions are arranged at intervals. When only one anchoring portion is provided on the skirt, the anchoring portion surrounds a part of the skirt in the circumferential direction.

[0006] In one embodiment, one end of the anchoring portion is a fixed end connected to the skirt, and the other end of the anchoring portion is a free end. When the anchoring portion is received in the conveying device, the free end is located on the proximal side of the fixed end. After the anchoring portion is released from the conveying device, the free end moves toward the distal side to cause the anchoring portion to turn outward.

[0007] In one embodiment, the skirt is a hollow tube with openings at both ends. The skirt includes a first support structure and a coating disposed on the first support structure. The distal end of the skirt is sealingly connected to the outer surface of the tube body, and the cross-sectional area of the skirt gradually increases in the direction from the distal end to the proximal end of the skirt.

[0008] In one embodiment, the anchoring portion includes a second support structure having shape memory characteristics. When the lumen stent is in a natural deployment state, the second support structure extends outward from the proximal end of the skirt.

[0009] In one embodiment, the first support structure and the second support structure are integrally formed.

[0010] In one embodiment, the anchoring portion further includes a connecting member. The connecting member is integrally formed with the second support structure, and the second support structure is connected to the first support structure through the connecting member.

[0011] In one embodiment, the angle formed between the second support structure and the generatrix of the skirt ranges from 30° to 90°.

[0012] In one embodiment, the angle formed between the generatrix of the skirt and the central axis of the skirt is 10° to 80°.

[0013] In one embodiment, at least one imaging member is provided on each anchoring portion.

[0014] In one embodiment, a coating is provided on the second support structure.

[0015] In one embodiment, the free end of the anchoring portion is bent toward a first side to form an arc-shaped structure on a second side of the anchoring portion.

[0016] In one embodiment, the total occupancy rate of the anchoring portions in the circumferential direction of the skirt is less than or equal to 50%.

[0017] In one embodiment, the tube body includes a circular proximal opening, and the ratio of the generatrix length of the skirt to the diameter of the proximal opening ranges from 0.5 to 1.2.

[0018] In one embodiment, the tube body includes a circular proximal opening, and the ratio between the length of the anchoring portion and the diameter of the proximal opening ranges from 0.4 to 1.

[0019] After the lumen stent of the present invention is implanted into the main body covered stent, the gap between the lumen stent and the fenestration area on the main body covered stent can be blocked by the skirt, and the anchoring of the lumen stent can be achieved through the anchoring portion. When multiple such lumen stents are implanted and the distance between the lumen stents is relatively close, since a single anchoring portion only surrounds a part of the skirt in the circumferential direction, or multiple anchoring portions are arranged at intervals in the circumferential direction, there are gaps around the anchoring portion. By staggering the anchoring portions of adjacent lumen stents, the situation of poor blocking effect caused by overlap or mutual extrusion deformation between adjacent lumen stents can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of a docking state between a branch stent and a main body stent in the prior art;

[0021] Figure 2 It is a schematic diagram of a docking state between another branch stent and a main body stent in the prior art;

[0022] Figure 3 It is a schematic structural diagram of a lumen stent provided by an embodiment of the present invention;

[0023] Figure 4 It is a schematic structural diagram of a lumen stent provided by another embodiment of the present invention;

[0024] Figure 5 For Figure 3 the top view of the lumen stent;

[0025] Figure 6 It is a schematic diagram of the shape of the skirt provided by an embodiment of the present invention;

[0026] Figure 7 For Figure 3 the schematic diagram of the first support structure and the anchoring portion unfolded in the same plane;

[0027] Figure 8 It is a schematic structural diagram of the skirt and the anchoring portion provided by an embodiment of the present invention;

[0028] Figure 9 It is a schematic structural diagram of the skirt and the anchoring portion provided by another embodiment of the present invention;

[0029] Figure 10 It is a schematic structural diagram of the skirt and the anchoring portion provided by still another embodiment of the present invention;

[0030] Figure 11 For Figure 10Top view of the middle skirt and the anchoring part;

[0031] Figure 12 Top view of the skirt and the anchoring part provided by another embodiment of the present invention;

[0032] Figure 13 Schematic diagram of the second arc structure provided by an embodiment of the present invention;

[0033] Figure 14 Schematic diagram after the lumen stent and the main stent are docked provided by an embodiment of the present invention;

[0034] Figure 15 Schematic diagram of the positional relationship of the anchoring parts of adjacent lumen stents after multiple lumen stents and the main stent are docked provided by an embodiment of the present invention. Detailed implementation manners

[0035] For the convenience of understanding the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the understanding of the disclosure of the present invention is more thorough and comprehensive.

[0036] It should be noted that when 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. The terms "outer", "inner", "end", "circumferential", "axial", "upper", "side", "near", "far" and similar expressions used herein are for illustrative purposes only.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0038] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions will be clearly and completely described below in conjunction with the embodiments of the end structures of different types of stents. Further, this embodiment is only a part of the embodiments in this application, rather than all the embodiments. In addition, when describing blood vessels, the orientation can be defined according to the blood flow direction. In the present invention, it is defined that the blood flow is from the proximal end to the distal end. When describing the stent, the inflow end of the stent is defined as the proximal end and the outflow end is defined as the distal end. The detailed implementation manners of the lumen stent are as follows:

[0039] Such as Figure 3As shown, an embodiment of the present invention provides a lumen stent 30, which includes a tube body 31 and a skirt 32 connected to the tube body 31.

[0040] Specifically, the tube body 31 is a hollow tube with openings at both ends, including a support skeleton and a tube body coating provided on the support skeleton. When the lumen stent 30 is implanted into the lumen, the tube body 31 can serve as a blood flow channel. The support skeleton has the ability to expand radially, can be radially contracted under an external force, and can self-expand or be mechanically expanded (for example, expanded by balloon dilation) after the external force is withdrawn to restore to its initial shape and maintain the initial shape. Thus, after being implanted into the lumen, it can closely adhere to the inner wall of the lumen through its radial support force. For example, the support skeleton can be a plurality of waveform rings arranged axially (not shown in the figure), or a mesh structure formed by weaving, or a cut mesh structure formed by cutting. The support skeleton can be made of a metal elastic material, which includes known materials implanted in medical devices or combinations of various biocompatible materials, such as alloys of two or more single metals among cobalt, chromium, nickel, titanium, magnesium, iron, as well as 316L stainless steel, nickel-titanium-tantalum alloy, etc., or other biocompatible metal materials. The tube body coating can be made of a polymer material with good biocompatibility such as polytetrafluoroethylene (abbreviated as PTFE), polyethylene terephthalate (abbreviated as PET), etc., and the tube body coating can be covered on the inner wall and / or outer wall of the support skeleton by means of suture or heat melting, etc., to play roles such as reconstructing the fluid channel and isolating the diseased area of the lumen.

[0041] The skirt 32 is a hollow tube with openings at both ends, including a first support structure 321 and a skirt coating 322 provided on the first support structure 321. The distal end of the skirt 32 is the end with a smaller cross-sectional area, the proximal end of the skirt 32 is the end with a larger cross-sectional area, and the cross-sectional area of the skirt 32 gradually increases along the direction from the distal end to the proximal end of the skirt 32. Among them, the cross-sectional area refers to the area of the cross-section intercepted by a plane perpendicular to the axis of the skirt 32.

[0042] The skirt 32 can be sleeved on the outer wall of the tube body 31, and is hermetically connected to the outer wall of the tube body 31 through the distal end of the skirt 32, so that the proximal opening of the tube body 31 is located between the proximal opening and the distal opening of the skirt 32, and a gap is formed between the outer wall of the tube body 31 and the inner wall of the skirt 32. After being implanted into the human body, when blood flows into the lumen stent 30 from the proximal end, it will also flow into this gap. Since the distal end of the skirt 32 is hermetically connected to the outer wall of the tube body 31, the blood flowing into this gap further plays a role of sealing and filling. As Figure 4As shown, the distal end of the skirt 32 can also be directly and sealingly connected to the proximal edge of the tube body 31, such that the proximal opening of the tube body 31 is near the distal opening of the skirt 32. Therefore, the skirt 32 covers only a very small part of the tube body 31, or hardly covers the tube body 31, such that the size of the skirt 32 after radial compression at its position is small, which can reduce the difficulty of sheathing and releasing the lumen stent 30. In other embodiments, the tube body 31 extends from the proximal opening of the skirt 32, that is, the proximal opening of the skirt 32 is in the distal direction of the proximal opening of the tube body 31. In addition, the connection between the skirt 32 and the tube body 31 can be achieved by thermally fusing the skirt film 322 of the skirt 32 with the tube film, or by sewing the distal end of the skirt 32 to the tube body 31.

[0043] In this embodiment, the skirt 32 can be frustum-shaped (or similar to a flared shape), and the skirt 32 can achieve circumferential sealing through radial supporting force. When the skirt angle β of the skirt 32 (the skirt angle refers to the included angle formed between the generatrix of the skirt 32 and the central axis of the skirt 32) is too large, after implanting into the lumen, it will cause too large a radial supporting force on the lumen, and further cause too large a stimulation to the inner wall of the lumen, and more seriously, it may cause damage to the inner wall of the lumen. When the skirt angle β of the skirt 32 is too small, the sealing effect of the skirt 32 is poor. Therefore, in this embodiment, the skirt angle β is set to 10° to 80°, which can avoid too large a stimulation and damage to the inner wall of the lumen by the skirt 32, and has a better sealing effect at the same time. In addition, the cross-sectional shape of the skirt 32 can be circular as Figure 5 shown, or elliptical as Figure 6 shown, or any other applicable shape. When the cross-sectional shape of the skirt 32 is elliptical, the skirt 32 can better fit the inner wall of the blood vessel with an approximately elliptical cross-section, and thus can reduce the stimulation of the skirt 32 to the inner wall of the blood vessel.

[0044] The first support structure 321 includes at least one loop of corrugated rings. As Figure 3 , Figure 5 shown, the first support structure 321 includes only one loop of corrugated rings. The corrugated rings include two circumferentially arranged corrugated units 323. Each corrugated unit 323 includes two proximal vertices 326, three distal vertices 325, two end points 327 (the two end points 327 are respectively the starting point and the ending point of the corrugated unit 323), and wave rods 328 connecting adjacent proximal vertices 326 and distal vertices 325, and wave rods 328 connecting the end points 327 and adjacent distal vertices 325. Among them, the proximal vertices 326 correspond to the wave peaks of the waveform, the distal vertices 325 correspond to the wave valleys of the waveform, and the two proximal vertices 326 and the two end points 327 are all located on the plane a (not marked in the figure), and the three distal vertices 325 are all located on the plane b (not marked in the figure).

[0045] In other embodiments, for the number of waveform units 323 in the waveform ring, three waveform units 323 can be provided as shown in Figure 8 , four waveform units 323 can be provided as shown in Figure 9 , and one waveform unit 323 can be provided as shown in Figure 11 . For the number of proximal vertices 326 and distal vertices 325 in the waveform unit 323, it can be set according to the specific application scenario with reference to Figure 5 , and the present invention does not limit this.

[0046] In this embodiment, by setting the first support structure 321 to include only one ring of waveform ring, it is beneficial to reduce the size of the first support structure 321 after radial compression, thereby reducing the difficulty of sheathing and releasing the lumen stent 30. It can be understood that in other embodiments, the first support structure 321 can also include multiple rings of waveform rings, and the multiple rings of waveform rings are arranged along the axial direction of the skirt 32, preferably connected into a mesh structure. Of course, the multiple rings of waveform rings can also be arranged in parallel at intervals. However, it should be noted that when the multiple rings of waveform rings are arranged in parallel at intervals and only connected to each other through the skirt film 322, the interval between adjacent waveform rings should not be too large. Any proximal vertex 326 in any one waveform ring (hereinafter referred to as waveform ring M) should be located between the cross-section where the proximal vertex 326 of the waveform ring (hereinafter referred to as waveform ring N) adjacent to the proximal end of M is located and the cross-section where the distal vertex 325 of N is located (that is, any proximal vertex 326 in M is located within the waveform ring N), so as to avoid the proximal part of the skirt 32 from turning outwards after the skirt 32 is released from the delivery device (such as a sheath tube) due to the excessive interval between adjacent waveform rings MN. The waveform ring can be made of a metal elastic material, for example, an alloy of two or more single metals among cobalt, chromium, nickel, titanium, magnesium, iron, as well as 316L stainless steel, nickel-titanium-tantalum alloy, etc., or other biocompatible metal materials.

[0047] The skirt film 322 can be made of a polymer material with good biocompatibility such as polytetrafluoroethylene (abbreviated as PTFE), polyethylene terephthalate (abbreviated as PET), etc. The skirt film 322 can be covered on the inner wall and / or outer wall of the first support structure 321 by means of sewing or heat melting to play a plugging role. As shown in Figure 3 , in this embodiment, the skirt film 322 completely covers the first support structure 321. It should be understood that the skirt film 322 can also partially cover the first support structure 321. Compared with the skirt film 322 partially covering the first support structure 321, the skirt film 322 completely covering the first support structure 321 can achieve a better plugging effect.

[0048] At least one anchoring portion 33 is provided in the circumferential direction of the skirt 32. When a plurality of anchoring portions 33 are provided on the skirt 32, the plurality of anchoring portions 33 are arranged at intervals. Specifically, as Figure 3 shown, two anchoring portions 33 arranged at intervals are provided on the skirt 32; as Figure 8 shown, three anchoring portions 33 arranged at intervals are provided on the skirt 32; as Figure 9 shown, four anchoring portions 33 arranged at intervals are provided on the skirt 32. The more the number of the anchoring portions 33, the stronger the anchoring performance. However, too many anchoring portions 33 may cause the intervals between the anchoring portions 33 to be relatively close. When a plurality of lumen stents 30 need to be implanted, the space for placing the anchoring portions 33 of adjacent lumen stents 30 is reduced. In addition, Figure 3 , Figure 8 and Figure 9 shown, the plurality of anchoring portions 33 are evenly spaced in the circumferential direction and have the same size and shape, which is beneficial to providing a relatively uniform anchoring force for the lumen stent 30. It can be understood that in some embodiments, the plurality of anchoring portions 33 may also be arranged at uneven intervals, and the shapes and sizes of the plurality of anchoring portions 33 on the same lumen stent 30 may also be different. As Figure 12 shown, when only one anchoring portion 33 is provided on the skirt 32, the anchoring portion 33 surrounds a part of the skirt 32 in the circumferential direction.

[0049] Referring to Figure 3 , one end of the anchoring portion 33 is a fixed end 33a connected to the skirt 32, and the other end of the anchoring portion 33 is a free end 33b. When the anchoring portion 33 is received in the delivery device, the free end 33b is located on the proximal side of the fixed end 33a (that is, on the side where the fixed end 33a is close to the proximal end of the lumen stent 30). After the anchoring portion 33 is released from the delivery device, the free end 33b moves to the distal side (that is, on the side where the fixed end 33a is close to the distal end of the lumen stent 30), so that the anchoring portion 33 flips outwards.

[0050] The anchoring portion 33 includes a second support structure 331. In one embodiment, the second support structure 331 is made of a shape memory metal material (such as nitinol), and can be a metal frame or metal sheet in one or more shapes of zigzag, finger-shaped, fan-shaped, or any other applicable shape. The second support structure 331 includes a first end and a second end connected to the skirt 32. The second support structure 331 is pre-shaped. Therefore, when the lumen stent 30 is in the natural deployment state (the natural deployment state refers to the natural stretching state without being affected by artificial external forces), the second support structure 331 extends outward from the skirt 32. During the process of accommodating the second support structure 331 in the delivery device, the delivery device drives the first end of the second support structure 331 to move proximally and towards the central axis of the lumen stent 30, so that the first end is located on the proximal side of the second end. After the second support structure 331 is released from the delivery device, its first end moves distally, so that the second support structure 331 flips outward to restore the pre-shaped form of the second support structure 331. At this time, an angle α is formed between the generatrix of the second support structure 331 and the skirt 32 (that is, the angle α formed between the plane where the second support structure 331 is located and the generatrix of the skirt 32).

[0051] Please refer to Figure 3 , the second support structure 331 can be integrally formed with the first support structure 321. When the lumen stent 30 is in the natural deployment state, the second support structure 331 extends outward from the proximal end of the skirt 32, and the second support structure 331 is pre-shaped (for example, pre-shaped by heat treatment), so that an angle is formed between the plane where the second support structure 331 is located and the generatrix of the skirt 32. Specifically, the first support structure 321 and the two second support structures 331 can be cut from a metal tube or wound with a metal wire. The metal tube or metal wire used has shape memory characteristics (for example, the metal tube or metal wire can be a shape memory alloy such as nitinol). As Figure 5 shown, the two second support structures 331 are arranged oppositely and each includes two support rods 334. One support rod 334 of the second support structure 331 is connected to the end point 327 of a waveform unit 323, and the other support rod 334 is connected to the end point 327 of another waveform unit 323.

[0052] Please refer to Figure 10, in another embodiment, the first support structure 321 and the second support structure 331 are not integrally formed. The two second support structures 331 are disposed opposite to each other and each includes two support rods 334, and are formed by winding a metal wire with shape memory characteristics. The anchoring portion 33 further includes a connecting member 333. One end of the connecting member 333 is connected to the second support structure 331, and the other end is connected to the first support structure 321. Specifically, the connecting member 333 includes two connecting wires, the connecting wires are integrally formed with the second support structure 331, and the two connecting wires are respectively wound around the two wave rods 328 of the first support structure 321. When the lumen stent 30 is in the natural deployment state, the second support structure 331 extends outward from the proximal end of the skirt 32, and the second support structure 331 is pre-shaped such that an angle is formed between the second support structure 331 and the generatrix of the skirt 32. It should be noted that the connection manner between the connecting member 333 and the first support structure 321 is not limited to Figure 10 the manner shown in

[0053] In this embodiment, referring to Figure 7 , in order to ensure that the anchoring portion 33 has sufficient anchoring force, the length L1 of the anchoring portion 33 should satisfy 0.4D1 ≤ L1 ≤ D1, where D1 (not marked in the figure) is the diameter of the proximal opening of the tube body 31 that is circular. Referring to Figure 3 , in order to ensure that the skirt 32 has a good sealing effect and reduce the difficulty of sheathing, the length L2 of the skirt 32 (i.e., the length of the generatrix of the skirt 32, not marked in the figure) should satisfy 0.5D1 ≤ L2 ≤ 1.2D1.

[0054] Referring to Figure 5 , in this embodiment, the total occupancy rate M of the anchoring portion 33 in the circumferential direction of the skirt 32 is less than or equal to 50%. The calculation method of the circumferential occupancy rate of the anchoring portion 33 in the skirt 32 is as follows: calculate the length L3 of an arc segment where the anchoring portion 33 intersects the skirt 32, and then calculate the cross-sectional perimeter L4 of the skirt 32 in the plane where this arc segment is located. The circumferential occupancy rate M of the anchoring portion 33 in the skirt 32 is calculated by the following formula:

[0055] M = L3 ÷ L4 X 100%

[0056] The sum of the occupancy rates M of all the anchoring portions 33 in the lumen stent 30 is obtained as the total occupancy rate of the anchoring portion 33 in the circumferential direction of the skirt 32.

[0057] It can be understood that before calculating the circumferential occupancy rate M of the anchoring portion 33 in the skirt 32, the length units of L3 and L4 need to be unified.

[0058] It should be noted that when calculating the length L3 of an arc where the anchoring portion 33 intersects the skirt 32, if the second support structure 331 of the anchoring portion 33 includes two support rods 334 and the gap between the two support rods 334 is not covered with a film, the anchoring portion 33 should be regarded as a whole (i.e., including the gap between the two support rods 334 on the plane where the anchoring portion 33 is located) intersecting the skirt 32, rather than just the two support rods 334 intersecting the skirt 32.

[0059] In addition, the higher the circumferential occupancy rate M of the anchoring portion 33 on the skirt 32, the more appropriately the length L2 can be reduced within the range of 0.4D1 ≤ L2 ≤ D1.

[0060] In this embodiment, in order to reduce the probability that the second support structure 331 damages the inner wall of the main body stent 20 and is corroded and decomposed by body fluids and tissues, the above-mentioned anchoring portion 33 further includes an anchoring section film 332 provided on the second support structure 331. As Figure 5 shown, the anchoring section film 332 completely covers the two support rods 334 of the second support structure 331 and the gap between the two support rods 334. A double-layer anchoring section film 332 can be used to completely wrap the two support rods 334 and the gap between the two support rods 334 between the anchoring section films 332. Alternatively, a single-layer anchoring section film 332 can be used to cover the side of the second support structure 331 in contact with the inner wall of the main body stent 20. In other embodiments, the anchoring section film 332 can also only cover the support rods 334 of the second support structure 331 without covering the gap between the support rods 334. The so-called covering means completely covering and wrapping the support rods 334. The anchoring section film 332 can also only cover part of the support rods 334 and the gap between the support rods 334.

[0061] In this embodiment, the first end of the above-mentioned second support structure 331 is provided with a structure with a smooth outer contour. As Figure 5 shown, a first arc-shaped structure 335 connecting the two support rods 334 is provided at the first end of the second support structure 331, which can prevent the second support structure 331 from damaging the inner wall of the main body stent 20 during the release process of the lumen stent 30.

[0062] In this embodiment, at least one radiopaque member (not shown in the figure) is provided on each anchoring portion 33 to achieve positioning of the anchoring portion 33 during the release process of the lumen stent 30. In order to more accurately position the edge of the anchoring portion 33, a plurality of radiopaque members can be provided at the edge position of the anchoring portion 33. For example, radiopaque members are provided on each support rod 334. The method of setting the radiopaque member can be: coating, plating or winding a radiopaque material on the anchoring portion 33.

[0063] When multiple such lumen stents 30 are combined for use in a fenestration procedure, the relevant blood vessel dimensions and positional relationships of the patient need to be measured before the operation. Multiple lumen stents 30 of appropriate sizes and structures are selected. One lumen stent 30 is received into the delivery device, and then the lumen stent 30 is delivered to a preset position (the inner cavity of the main stent 20) through the delivery device. Next, the lumen stent 30 is gradually released from the proximal end to the distal end through the delivery device. When the anchoring portion 33 is completely released, an angle α is formed between the anchoring portion 33 and the generatrix of the skirt 32. Pull the delivery device in the direction opposite to the feeding direction, so that the lumen stent 30 moves synchronously with the delivery device. The anchoring portion 33 is hooked to the inner wall near the fenestration area of the main stent 20, and then continue to pull the delivery device to turn the anchoring portion 33 towards the proximal end until the anchoring portion 33 fits against the inner wall of the main stent 20. At this time, the release position of each anchoring portion 33 can be determined by the imaging element on the anchoring portion 33. When the release position of the anchoring portion 33 does not meet the expectation, the lumen stent 30 can be rotated by rotating the delivery device to adjust the position of the anchoring portion 33. Then, appropriately pull the delivery device to make the anchoring portion 33 fit more closely against the inner wall of the main stent 20 (refer to Figure 14 ), and then gradually release the remaining part of the lumen stent 30 to complete the implantation of the lumen stent 30. Referring to the above method, continue to implant the remaining lumen stents 30. The anchoring portions 33 between adjacent lumen stents 30 can be in a parallel or mirror image positional relationship, Figure 15 which shows the positional relationships of the anchoring portions 33 of multiple adjacent lumen stents 30. The lumen stent 30 can be released with reference to this positional relationship. It can be understood that since a single anchoring portion 33 only surrounds a part of the skirt 32 in the circumferential direction, or multiple anchoring portions 33 are arranged at intervals in the circumferential direction, there are gaps around the anchoring portions 33. By staggering the placement of the anchoring portions 33 of adjacent lumen stents 30, it is possible to avoid the situation where adjacent lumen stents 30 overlap or are mutually extruded and deformed, resulting in poor occlusion effect.

[0064] It can be understood that when no imaging element is provided on the anchoring portion 33, the anchoring portion 33 can be adjusted to a preset position outside the body according to the relevant blood vessel dimensions and positional relationships of the patient, and the anchoring portion 33 can be loaded into the delivery device according to the preset position, so that the anchoring portion 33 can be released at the preset position.

[0065] In addition, please refer to Figure 3, the included angle α formed between the anchoring portion 33 and the generatrix of the skirt 32 should not be too large. An overly large included angle α will result in insufficient anchoring force of the anchoring portion 33, causing the lumen stent 30 to shift. Nor should the included angle α formed between the anchoring portion 33 and the generatrix of the skirt 32 be too small. An overly small included angle α will cause the anchoring portion 33 to be unable to flip proximally when the operator pulls the delivery device in the direction opposite to the feeding direction after the anchoring portion 33 is fully released, and thus unable to fit against the inner wall of the main stent 20. Therefore, it is appropriate to set the included angle α formed between the anchoring portion 33 and the generatrix of the skirt 32 to be 30° to 90°.

[0066] Furthermore, referring to Figure 13 , the free end 33b of the anchoring portion 33 is bent towards the first side to form a second arc-shaped structure 336 on the second side of the anchoring portion 33. Herein, the first side of the anchoring portion 33 refers to the side of the anchoring portion 33 facing proximally when the lumen stent 30 is in the natural deployment state, and the second side of the anchoring portion 33 refers to the side of the anchoring portion 33 facing distally when the lumen stent 30 is in the natural deployment state. After the anchoring portion 33 is fully released, when the operator pulls the delivery device in the direction opposite to the feeding direction, this second arc-shaped structure 336 is conducive to the smooth proximal flipping of the anchoring portion 33.

[0067] 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 to be within the scope described in this specification.

[0068] The above-described embodiments merely represent several implementation manners of the present invention. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent should be subject to the appended claims.

Claims

1. A lumen stent, comprising a tube body and a skirt connected to the tube body, characterized in that, At least one anchoring portion is provided on the skirt edge in the circumferential direction. When there are multiple anchoring portions on the skirt edge, the multiple anchoring portions are arranged at intervals. When only one anchoring portion is provided on the skirt edge, the anchoring portion surrounds a part of the skirt edge in the circumferential direction; One end of the anchoring portion is a fixed end connected to the skirt edge, and the other end of the anchoring portion is a free end. When the anchoring portion is received in the conveying device, the free end is located on the proximal side of the fixed end. After the anchoring portion is released from the conveying device, the free end moves to the distal side to cause the anchoring portion to flip outward; The anchoring portion includes a second support structure with shape memory characteristics, and the angle formed between the second support structure and the generatrix of the skirt edge is 30° to 90°.

2. The lumen stent according to claim 1, characterized in that, The skirt edge is a hollow tube with open ends at both ends. The skirt edge includes a first support structure and a coating provided on the first support structure. The distal end of the skirt edge is hermetically connected to the outer surface of the tube body, and the cross-sectional area of the skirt edge gradually increases in the direction from the distal end to the proximal end of the skirt edge.

3. The luminal stent according to claim 2, wherein, When the lumen stent is in the natural deployment state, the second support structure extends outward from the proximal end of the skirt edge.

4. The lumen stent according to claim 3, wherein The first support structure and the second support structure are integrally formed.

5. The lumen stent according to claim 3, wherein The anchoring portion further includes a connecting member, the connecting member is integrally formed with the second support structure, and the second support structure is connected to the first support structure through the connecting member.

6. The luminal stent according to claim 1, characterized in that, The angle formed between the generatrix of the skirt edge and the central axis of the skirt edge is 10° to 80°.

7. The lumen stent according to claim 1, characterized in that, The free end of the anchoring portion is bent toward the first side to form an arc-shaped structure on the second side of the anchoring portion.

8. The lumen stent according to claim 1, wherein, The total occupancy rate of the anchoring portion in the circumferential direction of the skirt edge is less than or equal to 50%.

9. The lumen stent according to claim 2, wherein The tube body includes a circular proximal opening, and the ratio range of the length of the generatrix of the skirt edge to the diameter of the proximal opening is 0.5 to 1.

2.

10. The lumen stent according to claim 1, wherein, The tube body includes a circular proximal opening, and the ratio range of the length of the anchoring portion to the diameter of the proximal opening is 0.4 to 1.

Images