CN114569301B

CN114569301B - Tectorial membrane support

Info

Publication number: CN114569301B
Application number: CN202011391335.2A
Authority: CN
Inventors: 肖本好; 明廷伯
Original assignee: Lifetech Scientific Shenzhen Co Ltd
Current assignee: Lifetech Scientific Shenzhen Co Ltd
Priority date: 2020-12-02
Filing date: 2020-12-02
Publication date: 2025-09-16
Anticipated expiration: 2040-12-02
Also published as: CN114569301A

Abstract

The present invention provides a stent graft, comprising a main body graft, a window formed on the surface of the main body graft, the stent graft further comprising an inscribed graft, the edge of the inscribed graft being connected to the main body graft, the window comprising a first edge and a second edge extending along the length extension direction of the stent graft, the inscribed graft and the main body graft being separately molded and then spliced together. The inscribed graft of the stent graft of the present invention is separately molded and then spliced together to form the main body graft, thereby greatly reducing the difficulty of manufacturing the stent graft.

Description

Tectorial membrane support

Technical Field

The invention relates to the field of medical instruments, in particular to a covered stent.

Background

Aortic aneurysms and aortic dissection are currently diseases that seriously jeopardize human life safety, and if not actively treated, the aortic aneurysm body and dissection will continue to expand and eventually rupture, causing serious complications and death. With the increasing number of patients suffering from hypertension, hyperlipidemia and hyperglycemia, the current incidence of aortic aneurysms and aortic dissection is also significantly increasing.

The traditional open surgery treatment aortic aneurysm and aortic dissection has the characteristics of large trauma, high mortality rate, long surgery time, high postoperative complication occurrence rate and high surgery difficulty, while the intracavity treatment has the characteristics of small trauma, less postoperative complication, short surgery time, low surgery difficulty and the like, so that the traditional open surgery treatment aortic aneurysm and aortic dissection gradually becomes the main mode for treating aortic aneurysm and aortic dissection at present. The covered stent is implanted in the aorta to isolate vascular lesions outside the covered stent, so that blood flow is restrained from flowing through the covered stent, and the purpose of protecting blood vessels is achieved. Because the fixation of the implantation of the covered stent and the prevention of blood flow flowing into the blood vessel through the proximal and distal ends of the stent are required, the covered stent needs to have an anchoring area with a certain length, when aortic aneurysm or interlayer involve the branch arterial vessel, the covered stent can be implanted to block the branch artery to different degrees for treatment, and even the treatment cannot be performed by the endoluminal technology.

For the endovascular treatment of aortic aneurysms or dissection involving branch arteries, fenestration stent technology and chimney stent technology are often employed in order to achieve the blood circulation of the branch arteries. The windowing stent technology is that a side hole is manufactured on a stent in an in-vitro or in-situ windowing mode is carried out on the covered stent, the position of the side hole corresponds to the position of an opening of a branch artery, the stent is implanted in an operation, the position of the opening is aligned with the branch artery, then a bridging stent is implanted through the branch artery to be matched with the covered stent, and the chimney stent technology is that the bridging stent is implanted through the branch artery to be matched with the covered stent after the covered stent is implanted. In general, the windowing stent technology has high positioning difficulty, needs customization, has long time, cannot be used for emergency treatment, is easy to leak, is limited by vascular anatomy, and has high difficulty in reconstructing multi-branch arteries. Meanwhile, whether a windowing bracket or a chimney bracket technology is adopted, before the branch artery is not rebuilt, the branch artery is always in an ischemic state, and the postoperative complication probability is high.

Disclosure of Invention

In order to solve the problems, the invention provides a covered stent, which comprises a main body covered film, wherein a window is formed on the surface of the main body covered film, the covered stent further comprises an inscription covered film, the edge of the inscription covered film is connected with the main body covered film, the window comprises a first edge and a second edge which extend along the length extending direction of the covered film stent, and the inscription covered film and the main body covered film are spliced and connected after being singly molded.

In an embodiment, the inscription covering film comprises a bottom part located between the first edge and the second edge, and a supporting unit is arranged on the inscription covering film, and the supporting unit makes the bottom part at least partially protrude outwards or partially concave inwards or parallel to the plane where the first edge and the second edge are located.

In an embodiment, the support unit includes a suture, and the suture passes through the upper and lower surfaces of the inner joint coating to the second edge after bypassing the first edge and the edge of the inner joint coating, and connects the inner joint coating and the main body stent after bypassing the second edge and the other edge of the inner joint coating.

In one embodiment, the inscribed coating has an elongation of greater than 0.01 and less than 0.1.

In an embodiment, the support unit comprises a wave-shaped support structure connected to the surface of the inscribed coating.

In an embodiment, the stent graft includes a window support member disposed outside the inner stent graft and protruding outward from a surface of the inner stent graft, and the wave-shaped support structure is integrally formed with the window support member.

In an embodiment, the inscription tectorial membrane includes bottom, proximal end folded-over portion and distal end folded-over portion are located respectively the bottom both ends, at least one of proximal end folded-over portion and distal end folded-over portion is located the internal surface of main part tectorial membrane, the supporting unit sets up in the bottom, and the folded-over portion is more close to the central axis of tectorial membrane support than the bottom.

In an embodiment, the surface of the window support is formed with a sinking section, and the area of the cross section of the covered stent where the sinking section is located is smaller than the area of the cross section of other parts of the covered stent far from the sinking section.

In an embodiment, the stent graft further comprises a main body support, the main body support is connected to the main body stent graft, the window support is a part of the main body support, and on the same cross section, the circumference Xiang Zhanbi of the window support is smaller than the circumference Xiang Zhan ratio of the main body support.

In one embodiment, the window support comprises a mesh structure having mesh openings, the size of the mesh openings being changeable by external forces.

In an embodiment, the proximal and/or distal ends of the window support extend beyond the edges of the window in the length direction of the stent graft.

The covered stent provided by the invention can effectively isolate aortic dissection and aortic aneurysm which are involved in aortic branch arteries, effectively rebuild the arterial blood circulation of the branch arteries, avoid long-time ischemia of the branch arteries, has small operation difficulty, does not need customization, and can be used for emergency treatment.

Drawings

FIG. 1 is a schematic view of the overall structure of a stent graft according to an embodiment of the present invention, including a main body stent, a branch stent, and an inscribed stent graft;

FIG. 2 is a schematic view of the structure of a main body stent in the stent graft shown in FIG. 1;

FIG. 3 is a schematic illustration of the stent graft of FIG. 1 after attachment of an inscribed stent graft to a branch stent;

FIG. 4 is a schematic illustration of an inscribed stent graft in the stent graft shown in FIG. 1;

FIG. 5 is a side view of the inscribed coating shown in FIG. 4;

FIG. 6 shows a top view of the stent graft shown in FIG. 1, with portions omitted;

FIG. 7 is a schematic view of a portion of a stent graft according to another embodiment of the present invention;

FIG. 8 is a schematic view of a portion of a stent graft according to another embodiment of the present invention;

FIG. 9 is a schematic view of the stent graft of the present invention after implantation into an aneurysm vessel;

FIG. 10 is a schematic structural view of a stent graft according to an embodiment of the present invention, including a window support;

FIG. 11 is a schematic view of the window support of FIG. 10;

FIG. 12 is a schematic view of a portion of the window support of FIG. 11;

FIG. 13 is a schematic outline view of a window support of a stent graft according to another embodiment of the present invention;

FIG. 14 is a simplified cross-sectional profile view of the stent graft shown in FIG. 13;

FIG. 15 is a schematic view of a window support of a stent graft according to an embodiment of the present invention;

FIG. 16 is an enlarged schematic view of a portion of the window support of FIG. 15;

FIG. 17 is a schematic view of a window support of a stent graft according to another embodiment of the present invention;

FIG. 18 is a schematic view of a branched stent structure of a stent graft according to an embodiment of the present invention;

FIG. 19 is a side view of a stent graft incorporating the branched stent shown in FIG. 18;

FIG. 20 is a schematic view of a branched stent structure of a stent graft according to another embodiment of the present invention;

FIG. 21 is a side view of a stent graft incorporating the branched stent shown in FIG. 20;

FIG. 22 is a schematic view showing a branched stent structure of a stent graft according to still another embodiment of the present invention;

FIG. 23 is a side view of a stent graft incorporating the branched stent shown in FIG. 22;

FIG. 24 is a schematic view of a portion of a stent graft according to an embodiment of the present invention;

FIG. 25 is a schematic view of a portion of the stent graft shown in FIG. 24;

fig. 26 is a schematic diagram showing a state before and after stretching of the inner contact film occurs;

FIG. 27 is a schematic view of a portion of a stent graft according to an embodiment of the present invention, including reinforcement members;

fig. 28 is a view showing several modifications of the reinforcing member shown in fig. 27.

Detailed Description

For a better understanding of the inventive concept, embodiments of the present invention will be described in detail below with reference to the drawings, the following specific examples are only some of the examples of the present invention and are not limiting of the present invention.

For the stent graft of the present invention, the end into which blood flows is defined as the "proximal end" and the end from which blood flows is the "distal end", i.e., blood flows from the proximal end to the distal end of the stent graft when in use.

Example 1

As shown in fig. 1, the stent graft 10 of the present embodiment has a hollow tubular structure having openings at both ends, and includes a main body stent 11, a branch stent 12, an inscribed stent graft 14, and a window support 15. Wherein, the surface of the main body bracket 11 is provided with a window 13, the edge of the inscription tectorial membrane 14 is connected with the main body bracket 1, and a window supporting piece 15 is arranged outside the inscription tectorial membrane 14 and protrudes outwards from the surface of the inscription tectorial membrane 14. The inner stent graft 14 is provided with a through hole which is communicated with the inner cavity of the stent graft 10, and the branch stent graft 12 is in a hollow cylindrical structure as shown in fig. 3, and is arranged inside the stent graft 10 and is communicated with the through hole on the inner stent graft 14, so that blood can flow into the branch vessel after passing through the branch stent graft 12. In this embodiment, the stent graft 10 comprises 3 branched stents 12, wherein two branched stents 12 are disposed near the proximal end of the window 13 and one branched stent 12 is disposed near the distal end of the window 13.

As shown in fig. 2, the main body bracket 11 includes a main body support 111 and a main body cover 112, and the main body support 111 is provided on the surface of the main body cover 112. It should be appreciated that the body support 111 may be disposed on the inner surface of the body cover 112, on the outer surface of the body cover, or on a portion of the outer surface of the body cover, and on another portion of the inner surface of the body cover.

The window 13 is open on the main body cover 112 and open in the middle of the main body cover 112, that is, there are a main body support 111 and a main body cover 112 between the end of the window 13 and the end of the main body bracket 11. In the present embodiment, the edges of the window 13 formed on the main body cover film 112 are rectangular, that is, when the main body cover film 112 is unfolded along a bus line which does not pass through the window, the window 13 is rectangular, and the window 13 has a first edge 131, a second edge 132, a third edge 133 and a fourth edge 134, and four edges enclose the window 13. Wherein the first edge 131 and the second edge 132 are opposite and coincide with the length extension direction of the stent graft 10, and the third edge 133 and the fourth edge 134 are opposite and are closer to the end of the stent graft 10 than the first edge 131 and the second edge 132. It will be appreciated that in other embodiments, the window may have other shapes, so long as the first edge and the second edge extend along the length of the stent graft, for example, may be at an angle to the length of the stent graft (e.g., the window is trapezoidal), or the first edge and the second edge are arc-shaped (e.g., the window is similarly oval), and the invention is not limited to the specific shape of the window. It will also be appreciated that the window may be near the proximal end of the stent graft or near the distal end of the stent graft.

As shown in fig. 1 and 4, the stent graft 10 of the present embodiment includes an inscribed stent 14, and the edge of the inscribed stent 14 is connected to the edge of the window. Specifically, the inner laminate film 14 includes a bottom portion 141 and a turnover portion 142, and the turnover portion 142 is provided at an end portion of the bottom portion 141. The turnover part 142 is disposed on the inner surface of the main body bracket, and the turnover part 142 is recessed toward the inner cavity of the main body bracket 11 to form a receiving cavity 144. The receiving cavity 144 has an upper edge 143, which upper edge 143 is connected to the third edge 133 of the window 13. Specifically, the turnover part 142 includes an upper turnover unit 1421 and a lower bottom unit 1422 connected to the bottom 141, where the sides of the upper turnover unit 1421 and the lower bottom unit 1422 are connected and jointly enclose to form the accommodating cavity 144.

It will be appreciated that in other embodiments, the edges of the inner interconnecting cover film may also be attached to the inner surface of the main body cover film.

As shown in fig. 5, the inscription stent graft 14 is further provided with a through hole 147 communicating with the lumen of the main stent graft, wherein the through hole 147 is opposite to the opening of the stent graft 10 and also opposite to the opening of the receiving cavity 144. Because the turnover part is provided with the accommodating cavity, when the implantation path of the bridging support is established, the guide wire or the guide pipe can extend into the branch support along the accommodating cavity, so that the implantation path of the bridging support can be established quickly, and the operation time is shortened.

Referring again to fig. 4, the inner covering film 14 of the present embodiment is provided with two turnups 142 (including a proximal turnup and a distal turnup respectively disposed at the proximal end and the distal end of the inner covering film), and the two turnups 142 are provided with through holes 147, wherein the proximal turnup 142 is provided with two through holes, and the distal turnup 142 is provided with one through hole. In the present embodiment, the fold-over portion is formed by folding back the end portion of the inner joint coating 14, specifically, the end portion of the inner joint coating 14 is folded away from the bottom 141 and toward the inner surface of the main body bracket 11. It will be appreciated that the two turndown configurations of the present embodiment may be identical or slightly different.

When the covered stent is used for bending a blood vessel, the included angle between the extension direction of the braided wire of the inscription covered stent and the length extension direction of the covered stent can be set to be larger than 0 degree in order to reduce the tension of the inscription covered stent which is applied to the bending of the blood vessel.

It is understood that in other embodiments, the inner covering film may be provided with only a turnover portion at the proximal end, and the number of through holes may be 1 to 3. In the present invention, the positions and the number of the branch brackets 12 correspond to the positions and the number of the through holes, that is, when a plurality of through holes are provided at one end of the inner joint coating, the same number of branch brackets 12 are correspondingly provided at the end of the inner joint coating, and the through holes can be arranged in a staggered manner or on the same cross section perpendicular to the central axis of the coating bracket.

It will also be appreciated that in other embodiments, the fold with the receiving cavity may be separately formed into a pocket with the receiving cavity and then connected to the base and window edges, respectively.

It will also be appreciated that in other embodiments, only one of the folds may form the receiving cavity, and the other fold is simply a slope transitioning from the bottom to the inner surface of the body support, although a through hole may be provided in this slope. It will also be appreciated that the through holes may also be provided on the bottom.

In this embodiment, the inner cover film 14 and the main cover film 112 are separately formed and then joined by stitching, but in other embodiments, the two can be joined by bonding or other means. Because the branch bracket is also arranged on the inscription tectorial membrane, the inscription tectorial membrane and the main body tectorial membrane are spliced after being singly molded, and the manufacturing difficulty can be greatly reduced. It will be appreciated that in other embodiments, the inner cover may be integrally formed with the main body cover when the turnover and the branch stent are not provided on the inner cover.

Returning again to fig. 4 and 5, the inner cavity (i.e., the size of the receiving cavity) of the turnover portion 142 of the present embodiment gradually decreases from the open position toward the through hole 147 (i.e., gradually decreases toward the opening of the end portion of the stent graft), so that the guide wire can be more quickly selected into the branch stent along the receiving cavity of 3 when the bridge stent is implanted.

Returning again to fig. 1 and 2, the window 13 of the stent graft 10 is further provided with a window support 15, the cross section of the window support 15 is in an arch structure and is arranged above the inscription stent graft 14, and protrudes outwards from the surface of the inscription stent graft 14. In this embodiment, the window support 15 and part of the main body support 111 are integrally formed, that is, the window support 15 is a part of the main body support 111, and when in preparation, a window is first opened on the main body coating, and then the main body support 111 is connected with the main body coating, wherein the main body support with the exposed window part forms the window support. And preferably the circumference Xiang Zhanbi of the window support of this embodiment is smaller than the body support, i.e. the window support has a smaller proportion of the circumference of the cross section than the body support in the same cross section, so that it is ensured that the lumen size of the body support is not too small at the location where the inscribed coating is provided, so that the hemodynamics in the aorta are not affected. It will be appreciated that in other implementations, the window support perimeter Xiang Zhan ratio may also be equal to or greater than the body support perimeter Xiang Zhan ratio.

As shown in fig. 6, the window support 15 of the present embodiment includes a plurality of support sections 151, the plurality of support sections 151 being axially spaced apart, the support sections 151 being circumferentially connected to the main body bracket 11 (fig. 6 only shows a partial structure of the main body bracket). In this embodiment, the support section 151 includes a plurality of end-to-end Z-shaped structures, and the Z-shaped structures have peaks and valleys, and the axial distance between the peaks and valleys is the wave height of the Z-shaped structures. In order to better implant the bridging stent into the branch stent and cooperate with the bridging stent, the interference and blocking of the bridging stent by the window supporting member are reduced as much as possible, in the window supporting member 15 of the present embodiment, the distance between the peak of the supporting section 151 near the third edge 133 of the window and the third edge 133 is preferably 10-20 mm, so that it is ensured that the bridging stent does not need to be specifically selected between the trough of the supporting section 151 and the third edge 133 when being implanted. Similarly, the distance between the trough of the support section near the fourth edge of the window and the fourth edge may be selected to be 10-20 mm. It is understood that in other embodiments, when the bridge support may be accurately selected to be placed between the trough and the third edge of the support section, the distance between the crest and the third edge of the support section near the third edge of the window may not be limited, and in this case, the wave height of the support section may be preferably 6-12 mm. Wherein reference numeral 01 in fig. 6 shows a part of the optional placement positions of the bridging brackets. In other embodiments, the implantation position of the bridging support frame may be optimized by changing the wave height of the support sections, for example, the wave height of the support sections near the third edge and/or the fourth edge may be set higher than the wave height of other support sections, or the support sections with higher wave heights may be set at the positions where the bridging support frame needs to be placed, which is not limited to the support sections near the third edge and the fourth edge.

It will be appreciated that in other embodiments, two adjacent support sections adjacent to the through-hole inscribing the stent are of inverted configuration, i.e. the peaks of one support section are opposed to the valleys of the other support section, such that the position between the opposed peaks and valleys can be selected when selecting the implantation position of the bridging stent.

As shown in fig. 6, in this embodiment, the third edge 133 of the window 13 is located between the window support 15 and the main body support 111, and the upper edge 143 of the turnover part 142 is connected to the third edge 133, at this time, in order to maintain the turnover part 142 in a good open configuration, a reinforcement member may be provided on the opening of the turnover part 142, for example, a seam may be increased or decreased on the upper edge 143 to appropriately reduce the deformability of the upper edge 143. It will be appreciated that in other embodiments it is also possible to have the third edge coincide with the body support or window support part (i.e. the support section partly covers the third edge of the window), in which case the opening edge (i.e. the upper edge) of the receiving cavity also coincides with the body support or window support part, i.e. the projection of the third edge and the upper edge of the receiving cavity both coincides with the body support or window support on a plane parallel to the bottom of the inscribed coating. At this time, the main body support or the window support can also function as an opening of the receiving cavity supporting the turnover part, which corresponds to the function of the reinforcement. It will also be appreciated that in other embodiments, the stiffener may be provided separately, as will be described in more detail below.

In other embodiments, as shown in fig. 7, the stent graft may further comprise a connector 252, the connector 252 being disposed over the window 23, and the plurality of support segments 251 being connected by the connector 252. In addition, the proximal and/or distal ends of the connector 252 may also extend onto the body support 211 to connect with the body support 211. The connectors 252 are preferably connected to the peaks of adjacent support sections 251. More preferably, the connector is located just on the large curved side of the stent graft when the stent graft is implanted into a curved vessel. In this embodiment, the connecting member 251 is a connecting rod, and the length extension direction of the connecting member 251 is consistent with the extension direction of the stent graft. It will be appreciated that in other embodiments, the connector may simply connect to the support section of the window support and not extend to the body mount. The material of the connecting piece can be selected from medical metal materials, such as super-elastic nickel-titanium wires, medical stainless steel wires and the like. The connecting piece and the supporting section can be connected by crimping or welding. It will be appreciated that in other embodiments, the connector may also be angled with respect to the length of the stent graft. Through setting up the connecting piece, can reduce the mutual interference between the support section, avoid the support to shrink simultaneously, improve window support's whole supporting property, also can make when tectorial membrane support is used for crooked blood vessel, because the restriction of connecting piece, the crest of support section 251 can not perk, can adapt to the crooked form of blood vessel better.

In other embodiments, as shown in fig. 8, the connection member 352 may include a plurality of segments 353, with two adjacent segments 353 being offset, and two adjacent support segments being connected by one segment 353. At this time, the segments 353 may be connected at any position of the adjacent two support segments, and it is preferable that the extending direction of the segments 353 coincides with the extending direction of the stent graft. Of course, the plurality of segments may be arranged without any dislocation, i.e., the connector shown in fig. 7 includes a plurality of segments. When the connecting piece comprises a plurality of sections which are arranged in a staggered way, the bridging stent is more flexible in selected position, and the bridging stent after implantation has a better matching form with the branch vessel.

As shown in fig. 9, the stent graft 10 of the present invention can be used for intra-luminal treatment of aortic arch aneurysms and treatment of thoracoabdominal aortic aneurysms. Because the window support is arranged on the window of the covered stent 10, the covered stent 10 can provide good radial supporting force, especially when being used for treating the interlayer aneurysm, even if the vacuum chamber is smaller, the covered stent 10 can also provide good radial supporting force before being implanted into the bridging stent 100, especially when the covered stent 10 is used for bending blood vessels, after the covered stent 10 adapts to the bending of the blood vessel morphology, due to the existence of the window support, the space between the window and the blood vessel wall is not excessively extruded, so that enough optional space is reserved for the implantation of the bridging stent 100. In addition, the blood flow supply of the branch vessel can be maintained all the time before the bridging stent 100 is implanted, the probability of ischemic complications after operation is greatly reduced, and meanwhile, abundant operation time is provided for doctors.

Example two

As shown in fig. 10, the stent graft 40 of the present embodiment has substantially the same structure as the stent graft 10 of the first embodiment, except for the window support 45. The window support 45 of the present embodiment is formed separately, and the main body support 411 opposite to the window support 45 has an open structure, that is, the support of the other part of the main body support has a closed ring structure, and the main body support 411 opposite to the window support 45 is not a complete ring shape.

As shown in fig. 11 and 12, the window supporter 45 of the present embodiment includes a plurality of supporting sections 451, the plurality of supporting sections 451 being connected to the edge of the body support window 43, and the plurality of supporting sections 451 being connected by hooking each other, thereby forming a mesh structure having mesh holes 456. The mesh structure includes a portion formed by braiding of braided filaments, the crossing points of which form the apices of mesh 456. The apexes of the mesh 456 are formed by the braid wires by being pressed or hung each other so that the crossing points of the braid wires are movable. Thus, the size of the mesh hole may be changed by an external force. For example, when the bridging stent is implanted, the sheath outside diameter of the conveyor is larger than the mesh, at this time, the mesh size can become larger under the extrusion of the sheath, or when the outside diameter of the implanted bridging stent is larger than the mesh size, the braided wires can not extrude the bridging stent, and the position of the bridging stent can be fixed to a certain extent, so that the stability of the bridging stent against the blood flow impact after implantation is increased.

As shown in fig. 12, two adjacent support sections 451 are connected by hanging each other, that is, the crest of one support section 451 is hooked with the trough of the other support section 451. The height h of the single supporting section 451 ranges from 6 to 20 mm, and the distance L0 between adjacent peaks and peaks or between adjacent troughs and troughs of the single supporting section 451 ranges from 10 to 25mm, so that the space can be prevented from being too small when the bridging support is implanted. There is a certain distance h0 between the crest and trough of two supporting sections 451 hooked to each other, this distance is between 0-5 mm, so, can leave certain tensile distance between the adjacent supporting sections, when the tectorial membrane support of this embodiment implants crooked blood vessel, window support piece orientation major curve side to, still can have certain tensile allowance between a plurality of supporting sections 451, tectorial membrane support can adapt to crooked blood vessel better.

Preferably, the same support section 451 comprises two support rings arranged in an overlapping manner in the circumferential direction, so that the mesh of the mesh structure is diamond-shaped, which also enhances the adherence and support of the window support to some extent. It will be appreciated that in other embodiments, a plurality of support rings may be included on the same support section, and when there are more support rings, the mesh size is smaller, so the number of support rings that are overlapped on the same support section is preferably 2-4.

In this embodiment, the window supporting member 45 is partially overlapped with the main body covering film of the main body support, so as to facilitate stitching of the window supporting member, and meanwhile, the window supporting member near the opening portion of the accommodating cavity of the folding portion can also play a role of a reinforcing member, so that good opening shape can be ensured. It will be appreciated that in other embodiments, the window support may not have any overlapping portions with the body cover film, and may be directly sewn by stitching.

It will also be appreciated that in other embodiments, the sum of the perimeter of the cross section of the window support and the perimeter of the cross section of the opposed body support is greater than the perimeter of the covering film over that cross section, i.e. there is a partial overlap of the window support and the body support in the circumferential direction, so that the adherence of the first and second edges of the window to the location and the support force of that portion can be suitably enhanced and the covering film support is less prone to collapse.

In this embodiment, the window support 45 transitions naturally with the surface of the body stent, that is, substantially the same for any cross section of the stent graft 40.

In other embodiments, as shown in fig. 13 and 14, the surface of the window support 55 forms a countersink 554, the countersink 554 being closer to the inscribed stent graft than other portions of the window support 55, such that the area of the cross-section of the stent graft where the countersink 554 resides is smaller than the area of the cross-section of other portions of the stent graft that are farther from the countersink 554. The two ends that link to each other with sinking section 554 still are equipped with changeover portion 555 and linkage segment 556, and wherein, changeover portion 555 is the inclined plane and sets up between sinking section 554 and linkage segment 556, and linkage segment 556 links to each other with the main part support, and the surface with the main part support is in same curved surface. It will be appreciated that in other embodiments, the connecting section may not be included, in which case the other end of the transition section is directly connected to the body support, or in other embodiments, the transition section is in a vertical plane. When the window support piece of the tectorial membrane support exists a sinking section, after the tectorial membrane support is implanted into a bent blood vessel, the deformation of the window support piece is small and is extruded by the blood vessel wall at the side of the large bending of the blood vessel relatively less, so that the reaction force of the window support piece to the blood vessel wall is also reduced, the long-term effect after the reconstruction of the diseased blood vessel is better, and the problems of secondary rupture and the like are not easy to occur.

In other embodiments, the window support and the opposite main support may be integrally woven, where the weaving density of the window support may be controlled to be greater than that of the opposite main support, so that the compliance of the whole stent graft (especially at the position where the window is opened) may be improved, and the adherence of the positions where the first edge and the second edge of the window are located may also be improved. Of course, in other embodiments, the window support may be woven separately from the contralateral body support, with the window support having a weave density greater than the contralateral body support.

Example III

The stent graft structure of this embodiment is substantially the same as that of the second embodiment except for the window support 65. As shown in fig. 15 and 16, the window support 65 of the present embodiment is cross-woven by weaving wires 657, and the mesh 656 has a diamond-shaped structure. When the mesh 656 is formed, the adjacent braided wires are overlapped with each other to form movable crossing points, so that all four vertexes of the mesh 656 can move, and the moving range is larger than that of the movable crossing points formed in a mutually hanging mode, therefore, the size of the mesh hole is not excessively limited, and even if the size of the mesh hole is smaller, the mesh hole can adapt to the implantation of the bridging stent and has a stabilizing effect on the bridging stent. In addition, the window support of the present embodiment does not have a peak or trough-like structure other than the end, and when the stent graft of the present embodiment is used to curve a blood vessel, there is less stimulation to the blood vessel.

In other embodiments, as shown in fig. 17, the window support 75 may include at least two support segments 751, with adjacent support segments 751 being connected by hooking each other, and each support segment may be formed by cross-braiding of braided filaments, i.e., a mesh-braided structure as shown in fig. 15. At this time, because the adjacent support segments 751 are connected in a mutually hooked manner, a certain stretching allowance can be further arranged between the adjacent support segments 751, and the covered stent can be better adapted to the curved blood vessel.

Example IV

In the first embodiment, the branched stent is in a hollow cylindrical structure, and the branched stent of the stent graft of this embodiment is shown in fig. 18. Specifically, the branch stent 82 includes a first segment 822 and a second segment 821 connected to one end of the first segment 822, wherein the first segment 822 has a cylindrical structure, the second segment 821 has a truncated cone structure, and both ends of the branch stent 82 have openings communicating with the inner cavities thereof. Wherein the opening of the first segment 822 is larger than the opening of the second segment 821, the outer diameter of the second segment 821 decreases gradually as it extends from the opening toward the first segment 822 (i.e., the first segment 821 is a flared segment). As shown in fig. 19, the projection of the first segment 822 falls within the projection of the second segment 821 on a cross section perpendicular to the central axis of the stent graft. When the branch stent 82 of the present embodiment is disposed between the proximal end of the window and the proximal end of the stent graft (i.e., when the branch stent 82 is in communication with the proximal through hole of the inner stent graft), the end of the first segment 821 opposite to the second segment 821 is connected to the turnover portion of the inner stent graft, and the end of the second segment 821 opposite to the first segment 822 is the free end, i.e., the first segment 822 is the proximal segment of the branch stent, and the second segment 821 is the distal segment of the branch stent. In contrast, when the branch stent 82 of the present embodiment is disposed between the distal end of the window and the distal end of the stent graft, the first segment 822 is the distal segment of the branch stent and the second segment 821 is the proximal segment of the branch stent.

The branch stent 82 of the present embodiment has a first section with a truncated cone shape, and a second section with a larger opening is communicated with the through hole of the inscribed coating, so that when a branch is selected, a guide wire or a conveyor is easier to enter the branch stent, and the bridging stent can be implanted more rapidly.

It will be appreciated that in other embodiments, the branch stent 92 may be an open structure. As shown in fig. 20 and 21, the branch stent 92 has a sheet-like structure having an arc-shaped curved surface, and the cross-sectional profile of the branch stent is C-shaped. Wherein the two sides between the proximal and distal ends of the branch stent 92 are connected to the inner surface of the main body stent, such that the space enclosed by the branch stent 92 and the inner surface of the main body stent constitutes the lumen of the branch stent 92. Because there is no other coating between the inner cavity of the branch stent 92 and the inner surface of the main stent, the material of the part is reduced, the overall thickness of the part of the coated stent is reduced, and the assembly difficulty of the coated stent is correspondingly reduced.

In other embodiments, when two bridging stents are required to be placed at one end of the inscribed stent, the branched stent may also have the structure shown in fig. 22, i.e., one end of the branched stent has one opening and the other end has two openings. With reference to fig. 22 and 23, the branch stent 102 is generally hollow and tubular in structure, including a first section 1021 and a second section 1022. The end of the first section 1021 far away from the second section 1022 is provided with an opening, the end of the second section 1022 far away from the first section 1021 is provided with two openings, the end of the first section 1021 far away from the second section 1022 is connected with the inscribed coating, and the end of the second section 1022 far away from the first section 1021 is a free end. In this way, the device is equivalent to only one branch stent connected with the inscription tectorial membrane, but two bridging stents can still be implanted, so that the internal leakage caused by stitching between openings of the branch stents is avoided.

It will be appreciated that in other embodiments, the extension direction of the branch stent disposed at the distal end of the inscribed stent graft may be at an angle greater than 0 degrees with respect to the length extension direction of the stent graft, or the branch stent connected to the distal end of the inscribed stent graft may extend toward the central axis of the stent graft, thereby facilitating implantation of the branch vessel bridging stent on the arch and reducing the degree of bending of the bridging stent.

Example five

The stent graft structure of this embodiment is substantially the same as that of the first embodiment, except for the inscription of the stent graft. As shown in fig. 24, the inscription film 114 is provided with a supporting unit 116, and the supporting unit 116 makes the bottom of the inscription film at least partially parallel to the plane where the first edge and the second edge of the window lie, or protrudes outwards from the plane, or is concave relative to the plane.

As shown in fig. 25, in this embodiment, the supporting unit 116 includes a suture line, which is formed from a position on the main body cover film adjacent to the first edge of the window as a starting point, and then is fixed to the main body cover film 1112 of the main body bracket around the second edge after passing through the upper and lower surfaces of the inner cover film 114 to the second edge of the window, that is, the suture line wraps around the inner cover film and the edge of the main body cover film adjacent to the second edge and the first edge of the window. The suture material can be selected from a high polymer material or a metal material, preferably a thinner flexible wire material, so that the compression loading of the covered stent is not influenced.

During stitching, the stitching thread penetrates from the inner surface of the main body coating film to the outer surface of the main body coating film, then bypasses the edge of the main body coating film, passes through the inner coating film from the upper surface of the inner coating film to the lower surface of the inner coating film, then penetrates the stitching thread back and forth on the inner coating film, then, after penetrating from the inner surface of the inner coating film to the outer surface close to the second edge, the stitching thread bypasses the main body coating film and the edge of the inner coating film, and penetrates the main body coating film from the outer surface of the main body coating film to the inner surface of the main body coating film, and a section of circumferential stitching is completed.

When the suture thread is threaded back and forth on the upper and lower surfaces of the inner joint coating, a plurality of suture points are formed on the surface of the inner joint coating. To reduce the effect of the suture on the bridge stent-graft lead-in, the suture points should not be too sparse, preferably the distance L2 between two adjacent suture points is less than 2 millimeters, and the distance L3 between the suture point on the inscription cover 114 closest to the first or second edge of the window is also less than 2 millimeters, and the distance L4 between the suture point on the body cover 1112 and the first or second edge of the window is also less than 2 millimeters.

In addition, the support unit 116 enhances the overall stability of the inscribed coating 114, reducing the deformability of the bottom of the inscribed coating 114. As shown in fig. 26, the axial length of the inscription membrane 114 in the natural state is denoted by L5, the length of the inscription membrane 114 when it is stretched under a force (for example, when the stent graft is used to bend a blood vessel) is denoted by L6, and the elongation θ is the ratio of the change in length of the inscription membrane 114 before and after stretching to the natural state. Because the support unit 116 limits the deformation degree of the inscription tectorial membrane 114, the inscription tectorial membrane elongation rate of the embodiment is smaller than 0.1 and larger than 0.01, so that the inscription tectorial membrane can adapt to the curved blood vessel on one hand and is not torn, and the other convenience can also ensure that the inscription tectorial membrane is not deformed too much and collapses.

It will be appreciated that in other embodiments, the support unit of the inscribed coating may also be a wave-shaped support structure resembling the support unit of the main body, i.e. the support unit is attached to the surface of the inscribed coating by stitching or heat treatment after being formed separately. Or the support unit may be integrally woven with the window support. Because the wave-shaped supporting structure has a certain wave height (namely axial length), the integrity of the supporting unit is better, and the supporting effect on the inscribed tectorial membrane and the deformation limiting effect are better. It will be appreciated that the support unit may be integrally formed with the body support, or a portion of the support unit may be integrally formed with the body support and a portion of the support unit may be integrally formed with the window support. Or a part of the supporting unit and the main body supporting piece are integrally formed, and a part of the window supporting piece and the main body supporting piece are integrally formed.

Preferably, the bottom of the inscription membrane is convex or planar, which ensures that the lumen of the body stent is not too small in size at the location where the inscription membrane is disposed, so as not to affect hemodynamics within the aorta.

In this embodiment, the inscription tectorial membrane and the main part tectorial membrane also splice the continuous after the shaping alone, like this, when setting up the supporting element on inscription tectorial membrane again, the preparation is more convenient.

It will be appreciated that, to allow for the open configuration of the inner-linked film turnover, the opening of the turnover may be slightly concave, that is, the turnover may be closer to the central axis of the film support than the bottom, and the support unit may be disposed only at the bottom of the inner-linked film. Because the axial length of the turndown is significantly less than the axial length of the bottom, even if the turndown is concave, the hemodynamics flowing through the body stent lumen will not be affected.

Example six

The stent graft structure of this embodiment is substantially the same as that of the second embodiment except for the stiffening members of the fold-over portion. To better maintain the folded portion in a good open configuration, as shown in fig. 27, the stent graft of the present embodiment includes a reinforcing member 127, and the reinforcing member 127 is disposed at an upper edge 1243 of the folded portion. In this embodiment, the stiffener 127 is a separate closed structure that is disposed around the opening of the flip, supporting the opening of the flip, reducing the deformability of the opening. The reinforcement 127 may be a wave-like structure similar to the body support or a closed structure surrounded by a wire. When the stiffener 127 is in a closed configuration, as shown in fig. 28, the portion connected to the upper edge 1243 of the folded portion is curved to accommodate the main body stent, and the opposite portion may be concave toward the central axis of the stent graft, or may be convex outward from the central axis of the stent graft or parallel to the central axis of the window and the stent graft.

It will be appreciated that in other embodiments, the stiffener may be of a simple open construction, that is, the stiffener has two circumferential free ends or edges, in which case the stiffener may be curved or curvilinear, or may be planar or linear in projection on a cross-section perpendicular to the central axis of the stent graft. In this case, the reinforcing member may be provided at any one of the opening sections of the turnup, that is, on the upper surface of the turnup where the upper edge is located (i.e., the upper turnup unit), on the lower surface of the turnup opposite to the upper edge (i.e., the lower bottom unit), or across the upper surface and the lower surface.

It will also be appreciated that the stiffening member may be formed separately, integrally with the window support, or integrally with the body support.

The above specific embodiments are only some embodiments of the present invention, and not limiting, and the present disclosure is not intended to be exhaustive or to limit all embodiments of the inventive concept, and some features of the above different embodiments may be replaced with each other or combined, and those skilled in the art may simply replace the features according to the actual needs, so that the inventive concept is subject to the scope of protection claimed.

Claims

1. A coated stent, comprising a main body coating, wherein a window is formed on the surface of the main body coating, characterized in that the window comprises a first edge and a second edge extending along the length extension direction of the coated stent, the coated stent also comprises an inscribed coating, the edge of the inscribed coating is connected to the main body coating, the inscribed coating and the main body coating are separately formed and then spliced together; the inscribed coating comprises a bottom and a folding portion located between the first edge and the second edge, the folding portion is provided at the end of the bottom, and the folding portion is provided on the inner surface of the main body coating.

2. The coated bracket according to claim 1 is characterized in that a support unit is provided on the inscribed coating, and the support unit makes the bottom at least partially convex outward or partially concave relative to the plane where the first edge and the second edge are located or parallel to the plane.

3. The coated bracket according to claim 2 is characterized in that the support unit includes a suture, and the suture passes around the first edge and the edge of the inner coating, passes through the upper and lower surfaces of the inner coating to the second edge, and then passes around the second edge and the other edge of the inner coating to connect the inner coating and the main bracket.

4 . The coated stent according to claim 1 , wherein the elongation of the inscribed coating is greater than 0.01 and less than 0.1.

5. The coated stent according to claim 2, characterized in that the support unit includes a corrugated support structure, and the corrugated support structure is connected to the surface of the inscribed coating.

6. The coated bracket according to claim 5 is characterized in that the coated bracket includes a window support, the window support is arranged outside the inner coating and protrudes outward from the surface of the inner coating, and the corrugated support structure is integrally formed with the window support.

7. The coated stent according to claim 2 is characterized in that the folding portion includes a proximal folding portion and a distal folding portion, and the proximal folding portion and the distal folding portion are respectively arranged at two ends of the bottom, and at least one of the proximal folding portion and the distal folding portion is arranged on the inner surface of the main body coating; the support unit is arranged at the bottom, and the folding portion is closer to the central axis of the coated stent than the bottom.

8. The coated bracket according to any one of claims 6 or 7, characterized in that a sunken section is formed on the surface of the window support, and the cross-sectional area of the coated bracket where the sunken section is located is smaller than the cross-sectional area of other parts of the coated bracket away from the sunken section.

9. The coated stent according to any one of claims 6 or 7 is characterized in that the coated stent also includes a main body support member, the main body support member is connected to the main body coating, the window support member is a part of the main body support member, and on the same cross-section, the circumferential proportion of the window support member is smaller than the circumferential proportion of the main body support member.

10. The stent graft according to any one of claims 6 or 7, wherein the window support comprises a network structure having meshes, and the size of the meshes can be changed by external force.

11. The stent graft according to any one of claims 6 or 7, wherein the proximal end and/or the distal end of the window support extends beyond the edge of the window in the length direction of the stent graft.