Covered stent and branched stent system

Abstract

The application relates to a covered stent and branch stent system, wherein the covered stent comprises a main stent, a concave part is formed in the circumferential wall surface of the main stent, an opening is formed on the main stent in the concave part, the opening is communicated with the inner cavity of the main stent, an embedded branch stent is fixedly arranged in the main stent and communicated with the opening, the embedded branch stent comprises an embedded branch wave ring and an embedded branch covering film covering the embedded branch wave ring, at least part of the embedded branch covering film is configured as a pleated elastic covering film, and the embedded branch stent can be expanded and contracted in the radial direction and / or the axial direction. The application aims to provide a covered stent capable of preventing the displacement of the main stent.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of interventional medical instrument equipment, and in particular to a covered stent and branch stent system. BACKGROUND

[0002] Aortic diseases such as aortic aneurysm and aortic dissection are one of the most deadly and most difficult to treat vascular surgical diseases. The traditional treatment method is through surgical operation, which has the risk of large surgical trauma and high mortality. In recent years, a minimally invasive and simple interventional surgical method has been developed, which implants a covered stent at the lesion blood vessel, and the covered stent is tightly attached to the inner wall of the blood vessel to isolate the blood flow from the blood vessel lesion. The covered stent can not only allow normal blood circulation, but also protect the blood vessel lesion and effectively repair the blood vessel lesion.

[0003] The aortic arch structure is complex, the aortic arch is in a curved state, and it is the main trunk for blood supply to internal organs and lower limbs; the branches on the arch are channels for maintaining blood supply to the brain and upper limbs, and the diameters and spacings of the branches are quite different among different individuals.

[0004] At present, after the main body stent of the aortic arch segment is released, each branch on the arch needs to be reconstructed. In the clinical practice of reconstructing the three branches on the arch, the guide wire and catheter (branch stent system) enter from the carotid artery or axillary artery opening, penetrate along the branch blood vessels, reach the junction of the branch and the aortic arch, and then select an embedded branch stent that matches the branch according to the product requirements. In this process, the structural characteristics of the aortic arch and the three branch blood vessels greatly affect the passability of the guide wire and catheter or the branch stent system inside the embedded branch stent. For example, when reconstructing the left subclavian artery branch access, the guide wire and catheter need to enter the aortic arch main body stent from the left subclavian artery branch, move to the embedded branch stent in the main body stent through the groove segment of the main body stent, and pass through the anchoring area that supports and fixes the distal end of the branch stent.

[0005] In the existing device, the embedded branch stent has a certain structural rigidity and is tightly attached to the top of the aortic arch. When the catheter enters the embedded branch stent from the left subclavian artery branch through the groove segment of the main body stent, the head end of the catheter needs to be deflected downward and backward, and the required turning angle of the catheter is less than 90°. When the catheter is inserted into the embedded branch stent, the included angle between the catheter and the embedded branch stent is large, and combined with the rigid characteristics of the embedded branch stent, the distal end of the catheter is easily in conflict with the wave coil of the embedded branch stent. The catheter has poor compliance inside the embedded branch stent, and if the catheter is continuously moved to the target position, the main body stent is likely to be displaced in the blood vessel. SUMMARY

[0006] In view of the above problems, the present application aims to provide a covered stent and branch stent system capable of preventing displacement of the main body stent.

[0007] The object is achieved by the following technical solutions:

[0008] According to a first aspect of the present application, a covered stent is provided, which comprises: a main stent, a circumferential wall surface of the main stent is concave to form a recess, an opening is formed on the main stent in the recess, and the opening is in communication with an inner cavity of the main stent; and an embedded branch stent, which is fixedly arranged in the main stent and in communication with the opening, and comprises an embedded branch wave ring and an embedded branch covering film covering the embedded branch wave ring, at least part of the embedded branch covering film is configured as a pleated elastic covering film, so that the embedded branch stent can expand and contract in the radial and / or axial directions.

[0009] In some embodiments of the present application, all of the embedded branch covering films are configured as the pleated elastic covering films.

[0010] In some embodiments of the present application, the embedded branch covering film comprises: an upper covering film; a lower covering film, which is arranged in a circumferential direction of the embedded branch stent and spaced apart from the upper covering film; and an intermediate covering film, which is located between the upper covering film and the lower covering film and connected to the upper covering film and the lower covering film respectively; at least part of the intermediate covering film is configured as the pleated elastic covering film.

[0011] In some embodiments of the present application, further comprising: an elastic member, a length direction of the elastic member extends in the circumferential direction, and two ends of the elastic member are connected to the upper covering film and the lower covering film respectively; or a plurality of elastic members, the plurality of elastic members are fixedly arranged in the intermediate covering film in sequence and in the axial direction, a length direction of the elastic member extends in the circumferential direction, and two ends of the elastic member are connected to the upper covering film and the lower covering film respectively.

[0012] In some embodiments of the present application, the main stent comprises a first segment, a second segment and a third segment connected in sequence, and in the circumferential direction, the second segment comprises a first part and a second part connected in sequence; wherein the first part extends in the circumferential direction of the main stent, the second part extends in the radial direction of the main stent, and the second part is recessed towards the inside of the main stent relative to the outer circumferential surface of the first segment and the second segment to form the recess, and the first segment and the second segment are both formed with the opening on the side towards the second part.

[0013] In some embodiments of the present application, in the axial direction, the second part comprises a proximal segment, an intermediate segment and a distal segment connected in sequence, and the intermediate segment is in the form of outward protrusion, so that the proximal segment and the distal segment are closer to the axis of the main stent relative to the intermediate segment.

[0014] In some embodiments of the present application, a smooth transition is provided between the intermediate segment and the proximal segment; and / or a smooth transition is provided between the intermediate segment and the distal segment.

[0015] In some embodiments of the present application, a first side edge covering film is provided on the circumferential edge of the proximal segment and connected to the first segment; and / or a second side edge covering film is provided on the circumferential edge of the distal segment and connected to the second segment.

[0016] In some embodiments of the present application, in the circumferential direction, the recess forms opposite first and second side edges on the circumferential wall of the main body stent, and at least one of the first and second side edges is provided with a developing structure.

[0017] In some embodiments of the present application, one of the first and second side edges is provided with a first developing structure, and the other is provided with a second developing structure, the first developing structure is a one-piece structure, and the second developing structure includes at least two developing sub-units, all of which are arranged in sequence and spaced apart in the axial direction.

[0018] In some embodiments of the present application, a top wave coil is further provided, which extends in the circumferential direction of the main body stent, and the two ends of the top wave coil are connected to the first and second side edges, respectively.

[0019] In some embodiments of the present application, the developing structure is a developing wire wound around the two ends of the top wave coil.

[0020] According to the second aspect of the present application, a branched stent system is further provided, which includes the covering stent of the first aspect of the present application, and at least one branched stent, the distal end of which is connected to the embedded branched stent in the covering stent.

[0021] The covering stent provided by the present application configures at least part of the embedded branched covering film as a pleated elastic covering film, so that the embedded branched stent has a certain self-elasticity. When the distal end of the catheter used to deliver the branched stent is inserted into the embedded branched stent and first contacts the inner wall surface of the embedded branched stent, the embedded branched stent is deformed elastically to increase the inner diameter of the embedded branched stent when it bears the downward pressure applied by the catheter, so as to offset part of the impact force of the catheter. As the catheter continues to advance distally, the embedded branched stent continues to deform to expand the inner diameter of its distal end, and the inner wall of the side of the embedded branched stent in contact with the catheter is inclined relative to the axis, so as to reduce the included angle between the catheter and the inner wall of the embedded branched stent, thereby avoiding the distal end of the catheter and the wave coil of the embedded branched stent from colliding with each other, thereby increasing the passability of the branched stent and reducing the risk of displacement of the main body stent. BRIEF DESCRIPTION OF DRAWINGS

[0022] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a better understanding of the preferred embodiments, and are not intended to be limiting of the application. Moreover, in the drawings, like reference numerals denote similar parts throughout the several views. In the drawings:

[0023] Figure 1 A structural schematic diagram of a covered stent according to an embodiment of the present application is shown schematically;

[0024] Figure 2 A partial structural schematic diagram of a covered stent according to an embodiment six of the present application is shown schematically;

[0025] Figure 3 A schematic diagram of an arch above three branch vessel reconstruction approach procedure of a branch stent system according to an embodiment of the present application is shown schematically;

[0026] Figure 4 A structural schematic diagram of an in-line branch stent according to an embodiment one of the present application is shown schematically;

[0027] Figure 5 A schematic diagram of a procedure of inserting a guidewire and catheter into an in-line branch stent according to an embodiment one of the present application is shown schematically;

[0028] Figure 6 A schematic diagram of a connection structure of a branch stent after being released to an in-line branch stent according to an embodiment one of the present application is shown schematically;

[0029] Figure 7 A structural schematic diagram of an in-line branch stent according to an embodiment two of the present application is shown schematically;

[0030] Figure 8 A schematic diagram of a procedure of inserting a guidewire and catheter into an in-line branch stent according to an embodiment two of the present application is shown schematically; Figure 7 A partial enlarged schematic diagram of part A is shown schematically;

[0031] Figure 9 A structural schematic diagram of a main stent according to an exemplary embodiment of an embodiment three of the present application is shown schematically;

[0032] Figure 10 A structural schematic diagram of a visualization structure according to an embodiment three of the present application is shown schematically;

[0033] Figure 11 A structural schematic diagram of a main stent according to an exemplary embodiment of an embodiment five of the present application is shown schematically;

[0034] Figure 12A perspective view schematically showing a main body support of an exemplary embodiment according to Embodiment 5 of the present application is shown schematically;

[0035] Figure 13 A structural view schematically showing a main body support of an exemplary embodiment according to Embodiment 5 of the present application is shown schematically;

[0036] Figure 14 A partial structural view schematically showing a covered stent according to Embodiment 6 of the present application is shown schematically;

[0037] Figure 15 A view schematically showing a top wave coil and a developing structure according to Embodiment 5 of the present application is shown schematically;

[0038] Figure 16 A structural view schematically showing a main body support of another exemplary embodiment according to Embodiment 3 of the present application is shown schematically;

[0039] Figure 17 A perspective view schematically showing a main body support of another exemplary embodiment according to Embodiment 3 of the present application is shown schematically;

[0040] Figure 18 A partial structural view schematically showing a covered stent according to Embodiment 4 of the present application is shown schematically;

[0041] Figure 19 A perspective view schematically showing a main body support according to Embodiment 4 of the present application is shown schematically.

[0042] Reference signs are as follows:

[0043] 100 - covered stent;

[0044] 10 - main body support, 11 - first segment, 12 - second segment, 121 - first portion, 1211 - concave segment wave coil, 122 - second portion, 1221 - proximal segment, 1222 - middle segment, 1223 - distal segment, 1224 - bottom wave coil, 12241 - proximal wave coil, 12242 - middle wave coil, 12243 - distal wave coil, 1225 - bottom cover, 13 - third segment, 110 - main body wave coil, 120 - main body cover, 101 - concave portion, 102 opening,

[0045] 20 - inner branch stent, 21 - inner branch coil, 211 - upper coil, 212 - lower coil, 22 - inner branch covering, 221 - upper covering, 2211 - first edge, 2212 - second edge, 222 - lower covering, 2221 - third edge, 2222 - fourth edge, 223 - intermediate covering, 2231 - first intermediate covering, 2232 - second intermediate covering;

[0046] 30 - elastic member;

[0047] 41 - first side edge covering, 42 - second side edge covering;

[0048] 50 - top coil;

[0049] 60 - developing structure, 61 - first developing structure, 62 - second developing structure, 621 - developing subunit, 601 - core wire, 602 - developing wire;

[0050] 201 - branch stent, 202 - catheter, 203 - guide wire;

[0051] 300 - aorta. DETAILED DESCRIPTION

[0052] Example embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings. While example embodiments of the present disclosure are shown in the drawings, it is understood that the present disclosure can be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0053] It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", "includes", "including" and "has", "having" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order in which they are described, unless specifically identified as an order dependent step. It is also to be understood that additional or alternative steps can be employed.

[0054] Although the terms first, second, third, etc. can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first", "second", and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0055] For ease of description, spatially relative terms can be used herein for the purpose of describing the relationship between one element or feature to another element or feature as illustrated in the figures. Such relative terms include terms such as "inner", "outer", "beneath", "below", "lower", "above", "upper", and the like. These spatially relative terms are intended to encompass different positions of the device in use or operation in addition to the positions depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "over" the other elements or features. Thus, the example term "below" can encompass both positions depending on the orientation of the device. The device can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0056] It should be noted that the terms "distal" and "proximal" are used as orientation terms that are commonly used in the field of interventional medical devices, where "distal" refers to the end of the device that is farthest from the operator during a procedure, and "proximal" refers to the end of the device that is closest to the operator during a procedure. Axial refers to a direction parallel to a line connecting a center of the distal end and a center of the proximal end of the medical device, and radial refers to a direction perpendicular to the axial direction.

[0057] Please refer to Figure 1 , Figure 3 and Figure 9 According to the embodiments of the present application, a covered stent is provided.

[0058] The covered stent 100 comprises a main body stent 10 and an embedded branch stent 20. The main body stent 10 comprises a main body wave coil 110 and a main body covering 120 covering the main body wave coil 110, and the main body stent 10 is arranged in the aorta 300 for reconstructing the arch of the aorta 300. In the embodiment, a portion of the circumferential wall surface of the main body stent 10 is recessed to form a recessed portion 101, and the recessed portion 101 has a whole groove structure, and an opening is formed in the main body stent in the recessed portion 101, wherein the opening can be formed in the side portion or the bottom portion, or a part is arranged in the side portion and a part is arranged in the bottom portion. In the embodiment, openings 102 are formed at both ends of the recessed portion 101 in the axial direction, the openings 102 are communicated with the inner cavity of the main body stent 10, and when the main body stent 10 is deployed in the arch of the aorta 300, the recessed portion 101 is arranged opposite to the supra-aortic three-branch vessels, so that when the supra-aortic three-branch vessels are reconstructed, the catheter 202 extending from the supra-aortic three-branch vessels can enter the inner cavity of the main body stent 10 through the opening 102.

[0059] The embedded branch stent 20 is fixedly arranged in the main body stent 10, and the embedded branch stent 20 can be fixed in the inside of the main body stent 10 by sewing or bonding. In the axial direction, one side of the embedded branch stent 20 is provided with the recessed portion 101, and one end of the embedded branch stent 20 is arranged opposite to and communicated with the opening 102, and the catheter 202 extending from the supra-aortic three-branch vessels can be inserted into the inside of the embedded branch stent 20 through the opening 102, so that after the branch stent 201 is deployed, the distal end of the branch stent 201 is anchored and supported by the embedded branch stent 20. Specifically, the number of the embedded branch stent 20 can be one, two or three, corresponding to the supra-aortic three-branch vessels respectively.

[0060] In the embodiment, as shown in Figures 3 to 5 The embedded branch stent 20 comprises an embedded branch wave coil 21 and an embedded branch covering 22 covering the embedded branch wave coil 21, and at least a part of the embedded branch covering 22 is configured as a pleated elastic covering, so that the embedded branch stent 20 has a certain self-elasticity. Figure 6When the distal end of the catheter 202 (as shown) is inserted into the embedded branch stent 20 and first contacts the inner wall surface of the embedded branch stent 20, the embedded branch stent 20 is subjected to the downward pressure applied by the catheter 202, and the elastic deformation of the embedded branch stent 20 causes the inner diameter of the embedded branch stent 20 to increase, thereby offsetting part of the impact force of the catheter 202. As the catheter 202 continues to advance distally, the embedded branch stent 20 continues to deform to expand the distal end of the embedded branch stent 20 and tilt the inner wall of the side of the embedded branch stent 20 in contact with the catheter 202 relative to the axis, thereby reducing the included angle between the catheter 202 and the inner wall of the embedded branch stent 20 and avoiding the distal end of the catheter 202 and the wave coil of the embedded branch stent 20 from colliding with each other, thereby increasing the passability of the branch stent 201 and reducing the risk of displacement of the main body stent 10.

[0061] It can be understood that the embedded branch covering film 22 can be partially provided as a wrinkled elastic covering film, or can be entirely provided as a wrinkled elastic covering film. In addition, the wrinkled direction of the wrinkled elastic covering film can be set according to actual needs. The wrinkled elastic covering film can be wrinkled in the circumferential direction, so that the embedded branch stent 20 can expand and contract in the radial direction; or the wrinkled elastic covering film can be wrinkled in the axial direction, so that the embedded branch stent 20 can expand and contract in the axial direction; or a part of the embedded branch covering film 22 is wrinkled in the circumferential direction, and the other part is wrinkled in the axial direction, so that the embedded branch stent 20 can expand and contract in both the radial direction and the axial direction, so as to achieve the purpose of increasing the passability of the branch stent 201 and reducing the risk of displacement of the main body stent 10.

[0062] The technical solutions of the present application will be described in further detail below in combination with specific embodiments.

[0063] Embodiment one

[0064] As Figure 1 , Figure 4 and Figure 5As shown, in the present embodiment, the embedded branch stent 20 comprises an embedded branch wave ring 21 and an embedded branch covering film 22, wherein the embedded branch covering film 22 is entirely provided as a pleated elastic covering film, and the pleated elastic covering film is pleated in the circumferential direction, so that the embedded branch stent 20 can expand and contract in the radial direction under the action of external force, and the inner diameter of the embedded branch stent 20 changes. The embedded branch covering film 22 can be connected to the embedded branch stent 20 by sewing or bonding, etc. When not subjected to external force, the diameters of the proximal end and the distal end of the embedded branch stent 20 in the released state are equal, and in the present embodiment, the inner diameter of the embedded branch stent 20 in the released state is 10 mm. When the embedded branch stent 20 is subjected to external force, the embedded branch stent 20 can continue to expand, and the maximum inner diameter of the embedded branch stent 20 can be expanded to 14 mm, i.e. the circumferential length of the embedded branch covering film 22 in the limit stretched state is 14π mm, and the size of the embedded branch wave ring 21 in the natural state (i.e. in the released state) is equal to the size of the embedded branch stent 20 expanded to the maximum under the action of force. Understandably, when the embedded branch stent 20 is not subjected to external force, the embedded branch wave ring 21 is in a compressed state under the constraint of the elastic force of the embedded branch covering film 22, and the inner diameter of the embedded branch wave ring 21 is smaller than the inner diameter of the embedded branch wave ring 21 in the natural state (i.e. in the released state).

[0065] In other embodiments, the size of the embedded branch stent 20 in the natural released state and the maximum expanded inner diameter size can also be set to other sizes according to actual needs, such as 9 mm in the natural state and 13 mm in the maximum expanded state under force, or 11 mm in the natural state and 15 mm in the maximum expanded state under force, etc., which are adaptively adjusted according to the actual size of the aorta 300 (see Figure 3 ) and the supra-aortic three-branch blood vessels of the patient, which are not specifically limited here.

[0066] In the present embodiment, please refer to Figure 3 and Figure 5As shown, when the branch stent 201 is implanted in the system of the main stent 10, when the catheter 202 carrying the branch stent 201 enters the embedded branch stent 20 along the guide wire 203, the distal end of the catheter 202 first contacts the inner wall of the bottom of the embedded branch stent 20, and at the same time, the catheter 202 applies pressure to the inner wall of the embedded branch stent 20 in the direction away from the axis of the embedded branch stent 20. Because the embedded branch covering film 22 is set as a pleated elastic covering film, the embedded branch stent 20 can deform elastically to some extent when subjected to pressure, offsetting part of the pressure, and at the same time, the inner diameter of the distal end of the embedded branch stent 20 increases, so that the inner wall of the embedded branch stent 20 in contact with the distal end of the catheter 202 is inclined relative to the axis of the embedded branch stent 20, so as to reduce the included angle between the embedded branch stent 20 and the catheter 202, and avoid the distal end of the catheter 202 and the wave coil of the embedded branch stent 20 from colliding with each other, thereby increasing the passability of the branch stent 201 and reducing the risk of displacement of the main stent 10.

[0067] In this embodiment, as shown in Figure 6 As shown, in the natural release state, the outer diameter size of the branch stent 201 is 1.1-1.2 times the inner diameter size of the embedded branch stent 20, so that after the branch stent 201 is completely released, the branch stent 201 is tightly attached to the embedded branch stent 20 under the elastic contraction force of the embedded branch covering film 22, so that the embedded branch stent 20 fixes the anchor area at the distal end of the branch stent 201.

[0068] It should be noted that in this embodiment, by setting all the embedded branch covering film 22 as a pleated elastic covering film, the embedded branch stent 20 has the ability to elastically deform after release, so as to better adapt to the branch stent 201, and based on the elastic deformation performance of the embedded branch stent 20, more size specifications of the branch stent 201 are compatible, and under the elastic contraction force of the embedded branch covering film 22, the branch stent 201 is more tightly attached to the embedded branch stent 20, reducing the blood permeation amount of the gap between the branch stent 201 and the embedded branch stent 20.

[0069] Embodiment two

[0070] In this embodiment, as shown in Figure 7As shown, the embedded branch stent 20 comprises an embedded branch coil 21 and an embedded branch covering 22, which can be connected to the embedded branch stent 20 by sewing or bonding or the like. The embedded branch covering 22 is partially provided as a pleated elastic covering. The embedded branch covering 22 comprises an upper covering 221, a lower covering 222 and an intermediate covering 223. Specifically, the upper covering 221, the lower covering 222 and the intermediate covering 223 are sequentially arranged along the circumferential direction of the embedded branch stent 20, and the intermediate covering 223 is located between the upper covering 221 and the lower covering 222 and connected to the upper covering 221 and the lower covering 222 respectively. The upper covering 221, the lower covering 222 and the intermediate covering 223 together enclose a cylindrical embedded branch covering 22 structure covering the embedded branch coil 21. The intermediate covering 223 is provided as a pleated elastic covering, so that the embedded branch stent 20 can expand and contract in the radial direction under the action of external force.

[0071] In one exemplary embodiment, each single coil in the embedded branch coil 21 is annular (not shown in the figure), and in the view angle in the axial direction, the upper covering 221 and the lower covering 222 are both semicircular, and the upper covering 221 and the lower covering 222 cover different regions of the embedded branch coil 21 in the axial direction respectively. In the circumferential direction, the upper covering 221 comprises a first edge 2211 and a second edge 2212, and the lower covering 222 comprises a third edge 2221 and a fourth edge 2222, wherein the first edge 2211 is arranged adjacent to the third edge 2221, and the second edge 2212 and the fourth edge 2222 are arranged adjacent to each other, and the intermediate covering 223 comprises two parts, a first intermediate covering 2231 and a second intermediate covering 2232, wherein the two sides of the first intermediate covering 2231 in the circumferential direction are connected to the first edge 2211 of the upper covering 221 and the third edge 2221 of the lower covering 222 respectively, and the two sides of the second intermediate covering 2232 in the circumferential direction are connected to the second edge 2212 of the upper covering 221 and the fourth edge 2222 of the lower covering 222 respectively. In this embodiment, the size of the embedded branch coil 21 in the natural state (i.e. in the released state) is equal to the maximum size of the embedded branch stent 20 in the stressed state. Understandably, when the embedded branch stent 20 is not subjected to external force, the embedded branch coil 21 is in a compressed state under the elastic constraint of the embedded branch covering 22, and the inner diameter of the embedded branch coil 21 is smaller than the inner diameter of the embedded branch coil 21 in the natural state (i.e. in the released state).

[0072] In another exemplary embodiment, as shown in FIG. 2B, the embedded branch covering 22 is provided as a pleated elastic covering, and the embedded branch coil 21 is provided as a plurality of single coils arranged in the circumferential direction of the embedded branch stent 20. The embedded branch covering 22 comprises an upper covering 221, a lower covering 222 and an intermediate covering 223. Specifically, the upper covering 221, the lower covering 222 and the intermediate covering 223 are sequentially arranged along the circumferential direction of the embedded branch stent 20, and the intermediate covering 223 is located between the upper covering 221 and the lower covering 222 and connected to the upper covering 221 and the lower covering 222 respectively. The upper covering 221, the lower covering 222 and the intermediate covering 223 together enclose a cylindrical embedded branch covering 22 structure covering the embedded branch coil 21. The intermediate covering 223 is provided as a pleated elastic covering, so that the embedded branch stent 20 can expand and contract in the radial direction under the action of external force. Figure 3 , Figure 7 and Figure 8As shown, the embedded branch wave circle 21 comprises an upper wave circle 211 and a lower wave circle 212, the upper cover film 221 is covered on the upper wave circle 211, and the lower cover film 222 is covered on the lower wave circle 212. In the visual angle along the axial direction, the upper cover film 221 and the upper wave circle 211 are semicircular, and the lower cover film 222 and the lower wave circle 212 are semicircular. Along the circumferential direction, the upper cover film 221 comprises a first edge 2211 and a second edge 2212, and the lower cover film 222 comprises a third edge 2221 and a fourth edge 2222. The first edge 2211 is arranged adjacent to the third edge 2221, and the second edge 2212 and the fourth edge 2222 are arranged adjacent to each other. The intermediate cover film 223 comprises a first intermediate cover film 2231 and a second intermediate cover film 2232, the two sides of the first intermediate cover film 2231 along the circumferential direction are connected with the first edge 2211 of the upper cover film 221 and the third edge 2221 of the lower cover film 222 respectively, and the two sides of the second intermediate cover film 2232 along the circumferential direction are connected with the second edge 2212 of the upper cover film 221 and the fourth edge 2222 of the lower cover film 222 respectively. In the embodiment, the cover film support 100 further comprises a plurality of elastic members 30, which can be helical springs. Along the axial direction, the plurality of elastic members 30 are arranged on the intermediate cover film 223 in sequence and at intervals, and are fixed on the intermediate cover film 223 in a suture manner. The length direction of the elastic member 30 extends along the circumferential direction, and the two ends of the elastic member 30 are connected with the upper cover film 221 and the lower cover film 222 respectively. Understandably, the self-elastic structure of the embedded branch stent 20 in the embodiment is mainly based on the joint action of the intermediate cover film 223 and the elastic member 30. When the embedded branch stent 20 is subjected to a radial pressure away from the axis direction of the embedded branch stent 20, the elastic member 30 can provide a rebounding force, and the elastic member 30 can also provide a supporting force for the intermediate cover film 223, so as to avoid the dislocation between the upper wave circle 211 and the lower wave circle 212 of the embedded branch stent 20 after being stressed, and ensure that the embedded branch stent 20 can stably maintain its own cylindrical structure, so as to provide support for the branch stent 201.

[0073] It should be noted that in the present embodiment, through the elastic deformation of the intermediate coating 223 and the elastic member 30, when the catheter 202 carrying the branch stent 201 enters the embedded branch stent 20 along the path of the guide wire 203, the distal end of the catheter 202 first contacts the inner wall of the bottom of the embedded branch stent 20, and at the same time the catheter 202 applies a pressure to the inner wall of the embedded branch stent 20 in the direction away from the axis of the embedded branch stent 20. Since the intermediate coating 223 is provided as a wrinkled elastic coating, the embedded branch stent 20 can deform elastically to some extent when subjected to pressure, thereby offsetting part of the pressure, and at the same time the inner diameter of the distal end of the embedded branch stent 20 increases, so that the inner wall of the embedded branch stent 20 in contact with the distal end of the catheter 202 is inclined relative to the axis of the embedded branch stent 20, so as to reduce the included angle between the embedded branch stent 20 and the catheter 202, thereby avoiding the distal end of the catheter 202 and the wave coil of the embedded branch stent 20 from colliding with each other, thereby increasing the passability of the branch stent 201 and reducing the risk of displacement of the main body stent 10.

[0074] Based on the elastic deformation performance of the embedded branch stent 20, the branch stent 201 of more size specifications is compatible, and under the action of the elastic contraction force of the intermediate coating 223 and the elastic member 30, the branch stent 201 is more closely attached to the embedded branch stent 20, thereby reducing the blood penetration amount of the gap between the branch stent 201 and the embedded branch stent 20.

[0075] Embodiment Three

[0076] In the present embodiment, the difference from the first embodiment or the second embodiment is the structure of the main body stent 10. The differences between the third embodiment and the first embodiment or the second embodiment will be described below, and the same or similar parts between the third embodiment and the first embodiment or the second embodiment will not be described here.

[0077] In the present embodiment, as shown in Figure 1 and Figure 9 , in the axial direction, the main body stent 10 includes a first segment 11, a second segment 12 and a third segment 13 connected in sequence. In the circumferential direction, the second segment 12 includes a first part 121 and a second part 122 connected in sequence, the first part 121 extends along the circumference of the main body stent 10, and in the axial direction, the first part 121 has a circular shape with one side open 102. The second part 122 extends along the radial direction of the main body stent 10, and in the axial direction, the second part 122 has a "chord" connected to the circular shape of the first part 121. The first part 121 includes a recessed segment wave coil 1211 and a partial main body coating 120 covering the outside of the recessed segment wave coil 1211 (see Figure 12 ), and the second part 122 includes a bottom wave coil 1224 and a bottom coating 1225 arranged on the bottom wave coil 1224 (see Figure 2). Understandably, the first portion 121 and the second portion 122 together constitute the circumferential contour of the second section 12. In the released state of the main body stent 10, the first section 11 and the second section 12 are both circular in the axial direction, the first portion 121 of the second section 12 is flush with the first section 11 and the second section 12 in the circumferential direction, the second portion 122 of the second section 12 is recessed relative to the outer circumferential surface of the first section 11 and the second section 12 to form the recessed portion 101, and the side of the first section 11 and the second section 12 towards the second portion 122 forms the opening 102. In this embodiment, in the released state of the main body stent 10, the recessed portion 101 is directly opposite the superior three-branch vessel, so that the catheter 202 extending from the superior three-branch vessel can first enter the recessed portion 101, and then be inserted into the embedded branch stent 20 in the inner cavity of the main body stent 10 through the opening 102 formed at either end of the recessed portion 101.

[0078] In this embodiment, as shown in Figure 9 、 Figure 11 、 Figure 13 and Figure 16 In the axial direction, the second portion 122 includes a proximal section 1221, an intermediate section 1222 and a distal section 1223 connected in sequence, the proximal section 1221 and the distal section 1223 are closer to the axis of the main body stent 10 relative to the intermediate section 1222, so that the intermediate section 1222 is more protruding relative to the proximal section 1221 and the distal section 1223, and the second portion 122 as a whole has a structure of high in the middle and low at both ends, which plays a guiding and directing role when the catheter 202 in the branch stent 201 system enters the recessed portion 101 of the main body stent 10 from the superior branch vessel, so that the catheter 202 can more smoothly enter the embedded branch stent 20 through the opening 102, and the risk of displacement of the second section 12 of the main body stent 10 under the pressure of the catheter 202 in the branch stent 201 system is reduced.

[0079] In one exemplary embodiment, as shown in Figure 9 and Figure 11As shown, the bottom wave coil 1224 includes: a proximal wave coil 12241 at the proximal segment 1221, a middle wave coil 12242 at the middle segment 1222, and a distal wave coil 12243 at the distal segment 1223. The recess 101 forms opposite first and second side edges on the circumferential wall surface of the main stent 10, the horizontal height of the middle wave coil 12242 is flush with the horizontal height of the first and second side edges, the proximal and distal wave coils 12241 and 12243 are of the same structure and wire diameter, and the horizontal height of the proximal and distal wave coils 12241 and 12243 is 2-5 mm lower than the horizontal height of the first and second side edges, so that the recess 101 has a structure of middle high and both ends low. In this embodiment, the opening 102 of the embedded branch stent 20 is directly connected to the proximal or distal wave coil 12241 or 12243, so that the distal end of the catheter 202 is slid into the embedded branch stent 20 under the guidance of the proximal or distal segment 1221 or 1223, greatly improving the passability of the catheter 202 in the branch stent 201 system, improving the efficiency of the branch approach establishment, and reducing the operation time.

[0080] In this embodiment, as shown in Figure 9 and Figure 10 , a segmented developing structure 60 is further provided on the first and second side edges, the developing structure 60 includes a core wire 601 and a developing wire 602, the material of the core wire 601 is selected from a nickel-titanium metal wire, and the developing wire 602 is wound on the core wire 601. The length of the developing structure 60 is 10-25 mm, the developing structure 60 is arranged on the corresponding first and second side edges of the proximal and distal segments 1221 and 1223, and the developing structure 60 is connected to the main stent 10 by a medical suture. By arranging the segmented developing structure 60, the positioning and judgment of the recess 101 of the main stent 10 by the doctor during the operation is more accurate, which is beneficial to further improve the efficiency of the branch approach establishment and reduce the position adjustment of the main stent 10. Moreover, the design of the segmented developing structure 60 enhances the boundary development of the recess 101 of the main stent 10 and maximally retains the flexibility of the whole main stent 10.

[0081] In another exemplary embodiment, as shown in Figure 16 and Figure 17As shown, the middle segment 1222 is raised relative to the proximal segment 1221 and the distal segment 1223, and there is a smooth transition between the middle segment 1222 and the proximal segment 1221 and between the middle segment 1222 and the distal segment 1223, so that the second part 122 forms an integrated structure with a middle raised portion and straight ends, and the second part 122 is generally wavelike. Specifically, the peak height of the raised middle segment 1222 is not more than one-half of the diameter of the embedded branch stent 20, the length of the middle segment 1222 in the axial direction is not more than one-half of the total length of the recess 101, and the arc length of the recess segment wave 1211 to which the middle segment 1222 is adapted is longer than the arc length of the recess segment wave 1211 to which the proximal segment 1221 and the distal segment 1223 are adapted, so that the raised structure of the middle segment 1222 can be more effectively radially supported. Two O-shaped developing structures 60 are provided at the peak position of the raised middle segment 1222 using medical sutures, so that the raised position of the recess 101 is more three-dimensional and clear in the image in the developing device, to facilitate the doctor to better observe the peak position of the raised portion during the operation. In this embodiment, when the branch access is established, please refer to Figure 3 and Figure 19 As shown, when the guide wire 203 and the catheter 202 are advanced from the superior branch vessel of the arch to the aorta 300, they first contact the raised middle segment 1222 of the recess 101, and then, under the guidance of the middle segment 1222, they reach the straight segment of the proximal segment 1221 or the distal segment 1223 of the recess 101 along the curvature of the middle segment 1222. In this process, the distal end of the guide wire 203 or the catheter 202 is bent under the guidance of the raised segment and the straight segment, reducing the included angle between the guide wire 203 or the catheter 202 and the axis of the embedded branch stent 20. If the guide wire 203 or the catheter 202 is continuously advanced, it will more smoothly extend into the embedded branch stent 20 to which it is adapted, and the establishment of the branch access is completed.

[0082] Embodiment Four

[0083] The difference between this embodiment and Embodiment Three is that the first side edge covering film 41 and the second side edge covering film 42 structures are additionally provided. The differences between Embodiment Four and Embodiment Three will be described below, and the same or similar parts between Embodiment Four and Embodiment Three will not be described again.

[0084] In this embodiment, as shown in Figure 18 and Figure 19As shown, the covered stent 100 further comprises a first side edge covering 41 and a second side edge covering 42. The first side edge covering 41 is arranged on the circumferential edge of the proximal segment 1221 and connected with the first segment 11, and the second side edge covering 42 is arranged on the circumferential edge of the distal segment 1223 and connected with the second segment 12. Specifically, the first side edge covering 41 and the second side edge covering 42 are in the shape of a triangle and arranged at four corners of the recessed part 101, and two straight edges of the first side edge covering 41 and the second side edge covering 42 are fixed on the bottom covering 1225 of the recessed part 101 and the main body covering 120 of the main body stent 10 respectively by medical sutures. Understandably, as shown in the figure, Figure 19 As shown, after the main body stent 10 is placed in the aortic arch 300 and released, the main body stent 10 is in a curved state as a whole, so that the middle segment 1222 of the recessed part 101 is more likely to form a three-dimensional structure with a middle bulge and two end recesses. During the movement of the guide wire 203 or the catheter 202 to the proximal segment 1221 or the distal segment 1223 under the guidance of the middle segment 1222, the first side edge covering 41 or the second side edge covering 42 can block the guide wire 203 or the catheter 202 from sliding out from the first side edge and the second side edge of the recessed part 101, preventing the guide wire 203 or the catheter 202 from entering the lesion tumor from the recessed part 101, and making the branch access more efficient and convenient.

[0085] Embodiment Five

[0086] The difference between the present embodiment and the third embodiment is the structure of the developing structure 60. The differences between the fifth embodiment and the third embodiment will be described below, and the same or similar parts between the fifth embodiment and the third embodiment will not be described here.

[0087] In the present embodiment, as shown in the figure, Figure 11 The first side edge is provided with a first developing structure 61, and the second side edge is provided with a second developing structure 62. The first developing structure 61 is a long strip-shaped integral structure, and extends from the proximal end of the first side edge to the distal end of the first side edge. The length of the first developing structure 61 is consistent with the length of the first side edge. The second developing structure 62 is a segmented structure, and comprises three developing sub-units 621, which are sequentially and spacedly arranged on the second side edge in the axial direction. Specifically, the length of the first developing structure 61 is 50-80 mm, and the length of each developing sub-unit 621 in the second developing structure 62 is 10-25 mm. The first developing structure 61 and the second developing structure 62 are both sutured to the main body stent 10 by medical sutures. In the present embodiment, the first developing structure 61 and the second developing structure 62 both use a nickel-titanium wire as a core wire 601, and the developing wire 602 is wound around the core wire 601. This has the advantages of good flexibility and clear development.

[0088] It can be understood that the first developing structure 61 and the second developing structure 62 are arranged respectively, and in the surgical process, the doctor can make more accurate judgment on the position of the recess 101 by observing the positions of the first developing structure 61 and the second developing structure 62 and the relative position between the two, so that the doctor can accurately judge the relative position of the first side edge and the second side edge, and then according to the relative position information of the first side edge and the second side edge, it can be judged whether the recess 101 of the main stent 10 exists circumferential deflection after release, so as to ensure that when the branch access is reconstructed, the recess 101 can accurately align the three-branch blood vessel on the arch, reduce the frequency of adjusting the main stent 10, and shorten the operation time.

[0089] In other embodiments, the first developing structure 61 is arranged on the second side edge, the second developing structure 62 is arranged on the first side edge, and the first developing structure 61 and the second developing structure 62 are the same as the above-mentioned embodiments, which will not be repeated here.

[0090] The first side edge is provided with the first developing structure 61, and the second side edge is provided with the second developing structure 62,

[0091] In other embodiments, as shown in Figure 13 , the first developing structure 61 and the second developing structure 62 adopt medical sutures with developing function, and the medical sutures with developing function are used to suture the boundary between the first part 121 and the second part 122 in the second segment 12 of the main stent 10. Not only does it make the production of the second segment 12 simple, but also it ensures the flexibility of the second segment 12 at the arch of the aorta 300. In this embodiment, the suture length of the developing medical suture penetrates the first side edge and the second side edge.

[0092] Embodiment six

[0093] The difference between this embodiment and embodiment three is that it also includes a top coil 50. The differences between embodiment six and embodiment three will be described below, and the same or similar parts between embodiment six and embodiment three will not be repeated here.

[0094] In this embodiment, as shown in Figure 1 , Figure 2 , Figure 14 and Figure 15As shown, the covered stent 100 further comprises a top coil 50, which is arranged in the recess 101, extends along the circumferential direction of the main stent 10, and has two ends connected with the first side edge and the second side edge respectively. The top coil 50 can support the second segment 12 in the circumferential direction after the main stent 10 is released, so as to avoid that the recess 101 is tightly attached to the inner wall of the aorta 300, and form a containing space between the recess 101 and the inner wall of the aorta 300, so that the guide wire 203 or the catheter 202 can move in the containing space between the recess 101 and the aorta 300, and be smoothly inserted into the embedded branch stent 20, and the establishment of the branch access is realized. In the embodiment, the developing silk thread 602 is wound on each landing point on both sides of the top coil 50 in the circumferential direction, the developing silk thread 602 is wound on the landing point of the top coil 50 in the same direction, the main covering 120 of the second segment 12, the bottom covering 1225 and the landing point of the top coil 50 are tightly connected by the medical suture, and the developing silk thread 602 is covered by the medical suture to prevent the developing silk thread 602 from falling off. Understandably, the developing silk thread 602 wound on the landing point of the top coil 50 can maximize the flexibility of the second segment 12.

[0095] According to the embodiment of the present application, a branch stent system is further provided, which comprises a covered stent 100 and at least one branch stent 201, and the distal end of the branch stent 201 is connected with the embedded branch stent 20 in the covered stent 100. The branch stent system provided by the present application can obtain more accurate circumferential positioning information of the main stent 10 after being released, reduce the adjustment frequency of the main stent 10, make the selection process of the guide wire 203 or the catheter 202 more smooth when the supra-aortic three branches are reconstructed, and make the doctor more smooth when the supra-aortic branch access is established, so as to reduce the operation time and reduce the operation risk.

[0096] The above description is only the preferred embodiment of the present application, but the protection scope of the present application is not limited to this. Any changes or replacements within the technical range disclosed by the present application can be easily thought by those skilled in the art, and should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A covered stent, characterized in that, The covered stent includes: The main support has a recessed portion formed by the inward concavity of its circumferential wall, and an opening is formed on the main support within the recessed portion, the opening communicating with the inner cavity of the main support. An embedded branch support is fixedly disposed within the main support and communicates with the opening. The embedded branch support includes an embedded branch waveband and an embedded branch coating covering the embedded branch waveband. At least a portion of the embedded branch coating is configured as a corrugated elastic coating, enabling the embedded branch support to extend and retract radially and / or axially. The embedded branch coating includes: Top coating; The lower cover film is spaced apart from the upper cover film along the circumferential direction of the embedded branch support; An intermediate film is located between the upper film and the lower film and is connected to both the upper film and the lower film respectively; At least a portion of the intermediate overlay is configured as the wrinkled elastic overlay; The covered scaffold also includes: An elastic element, the length of which extends in the circumferential direction, and both ends of which are connected to the upper cover film and the lower cover film respectively; or multiple elastic elements, the multiple elastic elements being fixedly disposed on the intermediate cover film at intervals in the axial direction, the length of which extends in the circumferential direction, and both ends of which are connected to the upper cover film and the lower cover film respectively.

2. The covered stent according to claim 1, characterized in that, The main support structure includes a first segment, a second segment, and a third segment connected in sequence. Along the circumferential direction, the second segment includes a first part and a second part connected together. The first portion extends circumferentially along the main support, the second portion extends radially along the main support, and the second portion is recessed into the interior of the main support relative to the outer periphery of the first segment and the second segment to form the recessed portion, and the opening is formed on the side of the first segment and the second segment facing the second portion.

3. The covered stent according to claim 2, characterized in that, Along the axial direction, the second part includes a proximal segment, an intermediate segment and a distal segment connected in sequence, wherein the intermediate segment is convex outward, such that the proximal segment and the distal segment are closer to the axis of the main support relative to the intermediate segment.

4. The covered stent according to claim 3, characterized in that, The intermediate segment and the proximal segment have a smooth transition; And / or a smooth transition between the intermediate segment and the distal segment.

5. The covered stent according to claim 3 or 4, characterized in that, Also includes: The first side film is disposed on the circumferential edge of the proximal segment and connected to the first segment; and / or The second side covering is located on the circumferential edge of the distal segment and connected to the second segment.

6. The covered stent according to claim 1, characterized in that, Along the circumferential direction, the recessed portion forms opposing first and second side edges on the circumferential wall surface of the main body support, and at least one of the first and second side edges is provided with a developing structure.

7. The covered stent according to claim 6, characterized in that, One of the first side and the second side is provided with a first developing structure, and the other side is provided with a second developing structure. The first developing structure is an integral structure, and the second developing structure includes at least two developing sub-units. All the developing sub-units are arranged sequentially at intervals along the axial direction.

8. The covered stent according to claim 6, characterized in that, Also includes: The top corrugated ring extends along the circumferential direction of the main support, and the two ends of the top corrugated ring are respectively connected to the first side and the second side.

9. The covered stent according to claim 8, characterized in that, The developing structure consists of developing threads wound around both ends of the top waveguide.

10. A branch support system, characterized in that, include: The covered stent as described in any one of claims 1-9; At least one branch stent, the distal end of which is connected to an embedded branch stent in the covered stent.

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