Aortic arch in situ fenestration dedicated covered stent

Abstract

The present invention relates to the technical field of medical devices, and discloses a special covered stent for in situ fenestration of an aortic arch, wherein the proximal end of the aortic covered stent is provided with 2-3 Z-wave stent rings (proximal Z-wave stent ring group) and 1 proximal small-wave stent ring, the distal end is provided with 3-4 Z-wave stent rings (distal Z-wave stent ring group), the middle section of the aortic covered stent is provided with a saddle-shaped metal stent ring, the aortic stent is fully covered with a coating, and the coating has a grid-like reinforcing wire. The special covered stent for in situ fenestration of an aortic arch mainly provides a special covered stent for in situ fenestration for in situ fenestration technology, which improves the success rate of fenestration and reduces the probability of stenosis caused by compression of the branch stent by the angle of the metal ring.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a special covered stent for in situ fenestration of an aortic arch. Background Art

[0002] At present, endovascular technology has been applied to the treatment of aortic arch diseases, among which the most critical is the reconstruction of the branch vessels above the arch. The current technologies mainly include pre-fenestration technology, chimney technology, branch stent technology and in situ fenestration technology, each with its own advantages and disadvantages. Due to the following problems, in situ fenestration technology is currently the more ideal method:

[0003] Pre-windowing technology is to modify the commercial finished stent on the spot, that is, trim the film to form a window. This process will damage the normal structure of the stent, making it difficult to ensure the long-term stability of the stent. In addition, during the operation, the window position needs to be aligned with the branch artery opening in the circumferential and axial directions, but accurate alignment is difficult and it is easy to cover the branch opening on the arch, causing serious complications. This method is difficult to operate and difficult to promote and implement;

[0004] The chimney technique is to release the branch stent graft through the guidewire reserved in the branch artery after releasing the main stent graft in the aortic arch. The front half of the branch stent graft needs to be placed in parallel with the main stent graft, and the rear half is located in the branch artery. Because the main stent graft and the branch stent graft squeeze each other in the tube wall and cannot fit tightly, this method leads to a higher risk of endoleak (blood flow continues to flow into the diseased area along the gap between the main stent graft and the branch stent graft), aortic wall damage and branch stent graft occlusion;

[0005] Branched stent technology, this technology is that the main stent itself is designed with branches, which can reconstruct branch arteries at the same time. However, the existing single-branch stent is difficult to adapt to the reconstruction of 2 or 3 supra-arch branch vessels; the existing double-branch stent can simultaneously reconstruct the brachiocephalic artery and the left common carotid artery, but cannot directly reconstruct the left subclavian artery, and hybrid surgery is required to reconstruct the left subclavian artery, which is still relatively traumatic; there are currently no commercially available 3-branch stents, and the finished 3-branch is difficult to adapt to different vascular anatomy, and customized 3-branch requires a long wait; there are also research reports showing that the incidence of cerebral stroke is higher with branched stent technology;

[0006] Therefore, the above technologies are difficult to provide suitable tools for the clinical endovascular treatment of aortic arch diseases. The in situ fenestration technology uses the existing commercial thoracic aortic covered stent. Through the fenestration instrument (puncture catheter, radiofrequency catheter or laser catheter), a window is opened on the aortic stent in reverse from the patient's branch vessel access to reconstruct the supra-arch branch vessels. 1-3 supra-arch branch vessels can be reconstructed intracavitary as needed without changing the original anatomy. There is no need for precise alignment when releasing the main stent. The use of existing commercial stents does not require customization time and is easy to promote.

[0007] The prior art has the following defects and deficiencies:

[0008] However, existing stents used in in situ fenestration technology often cannot control the position of the metal frame relative to the branch opening. Windowing is often difficult because the head end of the fenestration instrument is located on the Z-shaped wave metal frame, or is located at the angle of the metal ring, resulting in limited window size. After the branch stent is released, it is compressed by the angle, causing local stenosis of the branch stent. Summary of the invention

[0009] In view of the deficiencies in the prior art, the present invention provides a special covered stent for in situ fenestration of the aortic arch, which can solve the problem that when the prior stent is used, the head end of the fenestration instrument is often located on the Z-shaped wave metal frame, resulting in difficulty in fenestration, and the fenestration position is located at the angle of the metal ring, resulting in limited fenestration size and then the branch stent is compressed by the angle after release, resulting in local stenosis of the branch stent; the present invention mainly provides an aortic covered stent for in situ fenestration technology, which improves the success rate of fenestration and reduces the probability of branch stent stenosis caused by compression of the angle of the metal stent.

[0010] In order to achieve the purpose of improving the success rate of fenestration with the above-mentioned special covered stent for in situ fenestration of the aortic arch and reducing the probability of stenosis caused by compression of the branch stent by the angle of the metal stent, the present invention provides the following technical solutions: a special covered stent for in situ fenestration of the aortic arch, comprising an aortic covered stent, which can be used in combination with a branch stent, one end of the aortic covered stent is set to the proximal end, and the other end of the aortic covered stent is set to the distal end, a proximal Z-shaped wave stent ring group and a proximal small wave stent ring are arranged on the proximal end, a distal Z-shaped wave stent ring group is arranged on the distal end, a saddle-shaped metal stent ring group is arranged in the middle section of the aortic covered stent, the aortic covered stent is fully covered with a coating, a mesh reinforcing wire is arranged on the surface of the coating, and the mesh reinforcing wire is arranged with mutually matching latitude and warp threads inside.

[0011] Preferably, the aortic stent graft has an overall length of 80-200 mm and has no reinforcing ribs. The aortic stent graft is fully covered with a coating, wherein the most proximal Z-wave stent ring of the proximal Z-wave stent ring group is exposed for 0-50% of its length.

[0012] Preferably, the number of Z-wave support rings in the proximal Z-wave support ring group is 2-3, the spacing between the Z-wave support rings in the proximal Z-wave support ring group is 1mm-20mm, the nearest Z-wave support ring in the proximal Z-wave support ring group is a low-amplitude and multi-wave number Z-wave support ring, the nearest Z-wave support ring in the proximal Z-wave support ring group is 1mm-15mm away from the second Z-wave support ring, the surface of the nearest Z-wave support ring in the proximal Z-wave support ring group is coated to cover 50%-100% of the height, the amplitude of the proximal Z-wave support ring is 5-20mm, and the wire diameter of the proximal Z-wave support ring is 0.3-1.0mm.

[0013] Preferably, the number of the distal Z-wave support ring groups is 3-4, the distal Z-wave support ring groups are all covered with a film, the spacing between the Z-wave support rings of the distal Z-wave support ring group is 1mm-20mm, the amplitude of the Z-wave support rings of the distal Z-wave support ring group is 5-20mm, and the diameter of the metal wire of the distal Z-wave support ring group is 0.3-1.0mm.

[0014] Preferably, the number of the saddle-shaped metal bracket rings is 3-10, the spacing between the saddle-shaped metal bracket rings is 5mm-20mm, the overall section length of the saddle-shaped metal bracket ring is 50mm-120mm, the amplitude of the saddle-shaped metal bracket ring is 5-20mm, the metal wire diameter of the saddle-shaped metal bracket ring is 0.3-1.0mm, and the saddle-shaped metal bracket ring group is fully covered with a film.

[0015] Preferably, the coating material is eptfe, i.e. expanded polytetrafluoroethylene film, the coating thickness is 0.2-1.0mm, the mesh reinforcement wire material is eptfe with higher strength, and the mesh size of the mesh reinforcement wire is 5*5-10*10mm.

[0016] Compared with the prior art, the present invention provides a special covered stent for in situ fenestration of the aortic arch, which has the following beneficial effects:

[0017] 1. This is a special stent graft for in situ fenestration of the aortic arch. The overall length of the aortic stent graft is 80-200mm, without reinforcing ribs, to reduce the straightening force;

[0018] 2. This is a special stent graft for in situ fenestration of the aortic arch. The proximal end of the aortic stent graft is provided with a proximal Z-wave stent ring group to increase the sealing performance of the stent. The most proximal Z-wave stent ring of the proximal Z-wave stent ring group is a Z-wave stent ring with low amplitude and multiple waves. The coating covers 50%-100% of the height, which can reduce the stress concentration and damage of the proximal stent ring to the tube wall and enhance the sealing effect of the stent. The distal end is provided with a distal Z-wave stent ring group, which is fully covered with a coating to enhance the distal sealing effect and prevent distal end leakage.

[0019] 3. This is a special covered stent for in situ fenestration of the aortic arch. The design of the stent is to reduce the influence of the metal skeleton of the fenestration section on the fenestration. 3-5 saddle-shaped metal stent rings are designed in the middle section of the aortic covered stent, which can minimize the probability of metal wire blocking the fenestration device. The angle of the saddle-shaped metal stent ring without limiting the balloon expansion window can not only help to form a better shape of the window but also prevent the stent from being compressed by the angle to cause local stenosis. At the same time, the saddle-shaped metal stent ring has a certain radial support force to prevent the stent from collapsing. The spacing between the saddle-shaped metal stent rings is 5mm-20mm, which can provide sufficient flexibility for the stent and provide more metal-free area for fenestration.

[0020] 4. This is a special covered stent for in situ window opening of aortic arch. The coating is made of eptfe, that is, expanded polytetrafluoroethylene film, which is formed by overlapping hot pressing. The coating thickness is 0.2-1.0mm. The coating is designed with mesh reinforcement wires, which can effectively prevent the unlimited tearing of the coated window and the extension of the rupture caused by balloon expansion. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention from one angle (in a usage example).

[0022] In the figure: 1. Aortic stent graft; 2. Branch stent; 3. Proximal end; 4. Distal end. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] See also Figure 1 A special covered stent for in situ fenestration of an aortic arch comprises an aortic covered stent 1, which can be used in combination with a branch stent 2, one end of the aortic covered stent 1 is set as a proximal end 3, and the other end of the aortic covered stent 1 is set as a distal end 4, the proximal end 3 is provided with a proximal Z-shaped wave stent ring group and a proximal small-wave stent ring, the distal end 4 is provided with a distal Z-shaped wave stent ring group, the middle section of the aortic covered stent 1 is provided with a saddle-shaped metal stent ring group, the aortic covered stent 1 is fully covered with a coating, a mesh reinforcing wire is provided on the surface of the coating, and the mesh reinforcing wire is provided with mutually matching latitudes and warps.

[0025] In summary, the overall length of the aortic covered stent 1 is 80-200mm, without reinforcement ribs, the aortic covered stent 1 is covered with a membrane throughout, wherein the first Z-wave stent ring at the most proximal end of the proximal Z-wave stent ring group is exposed 0-50% of the length, and the aortic covered stent 1 has no reinforcement ribs to reduce the recoil force; the number of Z-wave stent rings in the proximal Z-wave stent ring group is 3-4, the spacing between the Z-wave stent rings in the proximal Z-wave stent ring group is 1mm-20mm, the most proximal Z-wave stent ring of the proximal Z-wave stent ring group is a Z-wave stent ring with low amplitude and multiple waves of 8-16, and the most proximal first Z-wave stent of the proximal Z-wave stent ring group The distance between the ring and the second Z-wave bracket ring is 1mm-15mm. The first Z-wave bracket ring at the most distal end of the proximal Z-wave bracket ring group is a Z-wave bracket ring with low amplitude and multiple waves. The coating covers 50%-100% of the height, which can reduce the stress concentration and damage of the proximal bracket ring to the tube wall, and can also enhance the sealing effect of the bracket. The number of Z-wave bracket rings in the distal Z-wave bracket ring group is 3-4, and the distal Z-wave bracket ring group is fully covered with a coating. The distance between the Z-wave bracket rings of the distal Z-wave bracket ring group is 1mm-20mm, the amplitude of the Z-wave bracket ring of the distal Z-wave bracket ring group is 5-20mm, and the wire straightness of the distal Z-wave bracket ring is 1mm-20mm. The diameter is 0.3-1.0mm, and it is fully covered with a film to enhance the distal sealing effect and prevent distal internal leakage; the number of saddle-shaped metal stent rings is 3-10, the spacing between the saddle-shaped metal stent rings is 5mm-20mm, and the overall length of the saddle-shaped metal stent ring is 50mm-120mm, which can minimize the probability of metal wire blocking the window opening device. There is no angle on the saddle-shaped metal stent ring that limits the balloon expansion window, which can be conducive to forming a better window shape and prevent the branch stent from being compressed by the angle and causing local stenosis. At the same time, the saddle-shaped metal stent ring has a certain radial support force to prevent the stent from collapsing. The spacing between the saddle-shaped metal stent rings is 5m The m-20mm wide distance design can provide sufficient flexibility for the stent and provide more metal-free area for window opening; the coating material is eptfe, that is, expanded polytetrafluoroethylene film, the coating thickness is 0.2-1.0mm, the mesh reinforcement wire material is eptfe with higher strength, the mesh size of the mesh reinforcement wire is 5*5-10*10mm, the coating 9 is made of eptfe material, that is, expanded polytetrafluoroethylene film, overlapping hot pressing forming, the coating 9 thickness is 0.2-1.0mm, the coating is designed with mesh reinforcement wire warp and weft lines, which are higher strength eptfe lines, which can effectively prevent the balloon expansion from causing unlimited tearing of the coating window and extension of the rupture.

[0026] The working use process and installation method of the present invention are as follows: when the special covered stent for in situ fenestration of the aortic arch is used for intracavitary treatment of aortic arch diseases and reconstruction of the three-branch arteries on the arch is required, first establish temporary extracorporeal circulation via the axillary femoral artery bypass. The stent of the present invention is compressed and entered into the conveyor, introduced into the conveyor through the femoral artery and delivered to the aortic arch. The head end of the conveyor enters the ascending aorta, and the conveyor is controlled to release the stent of the present invention. After the stent is completely released, the proximal Z-shaped wave stent ring group of the stent is located in the ascending aorta and the proximal end of the opening of the brachiocephalic artery, the middle saddle-shaped stent ring group is located in the aortic arch, and the distal Z-shaped wave stent ring group is located in the descending aorta and the distal end of the opening of the left subclavian artery. At this time, the temporary extracorporeal circulation is turned on. Further, a fenestration instrument is introduced through the right carotid artery to the opening of the brachiocephalic trunk, a "window" is made on the membrane of the aortic stent graft, and a small stent is implanted; similarly, a fenestration instrument is introduced through the left carotid artery to the opening of the left common carotid artery, a "window" is made on the membrane of the aortic stent graft, and a small stent is implanted; similarly, a fenestration instrument is introduced through the left brachial artery to the opening of the left subclavian artery, a "window" is made on the membrane of the aortic stent graft, and a small stent is implanted; in this way, the special stent of the present invention is used to complete the intracavitary treatment of the aortic arch through the in situ fenestration technology, while maintaining the blood supply of the three branch arteries on the arch;

[0027] The present invention relates to a special covered stent for in situ fenestration of the aortic arch. The aortic covered stent 1 has an overall length of 80-200 mm and no reinforcing ribs, thereby reducing the straightening force. The proximal end 3 of the aortic covered stent 1 is provided with a proximal Z-wave stent ring group to increase the sealing performance of the stent. The most proximal end of the proximal Z-wave stent ring group is a Z-wave stent ring with low amplitude and multiple waves, and the covering covers 50%-100% of the height, which can reduce the stress concentration and damage of the proximal stent ring to the tube wall and also enhance the sealing effect of the stent. The distal end 4 is a distal Z-wave stent ring group structure, which is fully covered with a film to enhance the distal sealing effect and prevent distal internal leakage. The stent design is to reduce the impact of the metal skeleton in the fenestration section on the fenestration, the metal wire blocking the fenestration part of the fenestration device or the metal angle limiting the expansion of the window. 3-5 saddle-shaped metal stent rings are designed in the middle section of the aortic covered stent 1 to minimize the probability of the metal wire blocking the fenestration device. The saddle-shaped metal stent ring has no angle that limits the balloon expansion window, which can be conducive to forming a window with a better shape and prevent the stent from being compressed by the angle to cause local stenosis. At the same time, the saddle-shaped metal stent ring has a certain radial supporting force to prevent the stent from collapsing. The saddle-shaped metal stent ring is designed with a wide distance of 5mm-20mm to provide sufficient flexibility for the stent and provide more metal-free area for the fenestration. The coating is made of eptfe material, that is, expanded polytetrafluoroethylene film, which is overlapped and hot-pressed. The coating thickness is 0.2-1.0mm, and the coating is designed with mesh reinforcing wire warp and weft, which is a higher strength eptfe line, which can effectively prevent balloon expansion from causing unlimited tearing of the coated window and extension of the rupture.

[0028] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0029] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A special covered stent for in situ fenestration of aortic arch, characterized by: The invention comprises an aortic stent graft (1), wherein the aortic stent graft (1) can be used in combination with a branch stent (2), wherein one end of the aortic stent graft (1) is set as a proximal end (3), and the other end of the aortic stent graft (1) is set as a distal end (4), wherein the proximal end (3) is provided with a proximal Z-shaped wave stent ring group and a proximal small wave stent ring, and the distal end (4) is provided with a distal Z-shaped wave stent ring group, and the middle section of the aortic stent graft (1) is provided with a saddle-shaped metal stent ring group, wherein the saddle-shaped metal stent rings in the saddle-shaped metal stent ring group have no angle that restricts the balloon expansion window, and the aortic stent graft (1) is covered with a coating throughout, and a mesh reinforcing wire is provided on the surface of the coating, and mutually matching latitudes and warps are provided inside the mesh reinforcing wire; the number of Z-shaped wave stent rings in the proximal Z-shaped wave stent ring group is 2-3, and the Z-shaped wave stent rings in the proximal Z-shaped wave stent ring group are 2-3. The spacing between the Z-shaped wave bracket rings is 1mm-20mm, the nearest Z-shaped wave bracket ring of the proximal Z-shaped wave bracket ring group is a Z-shaped wave bracket ring with low amplitude and multiple wave numbers, the nearest Z-shaped wave bracket ring of the proximal Z-shaped wave bracket ring group is 1mm-15mm away from the second Z-shaped wave bracket ring, the surface coating of the nearest Z-shaped wave bracket ring of the proximal Z-shaped wave bracket ring group covers 50%-100% of the height, the amplitude of the proximal Z-shaped wave bracket ring is 5-20mm, and the metal wire diameter of the proximal Z-shaped wave bracket ring is 0.3-1.0mm; the number of the saddle-shaped metal bracket rings is 3-10, the spacing between the saddle-shaped metal bracket rings is 5mm-20mm, the overall section length of the saddle-shaped metal bracket ring is 50mm-120mm, the amplitude of the saddle-shaped bracket ring is 5-20mm, the metal wire diameter of the saddle-shaped metal bracket ring is 0.3-1.0mm, and the saddle-shaped bracket ring group is fully covered with a coating.

2. The stent graft for in situ fenestration of the aortic arch according to claim 1, characterized in that: The aortic stent graft (1) has an overall length of 80-200 mm and has no reinforcing ribs. The aortic stent graft (1) is fully covered with a coating, wherein the most proximal Z-shaped wave stent ring of the proximal Z-shaped wave stent ring group is exposed for 0-50% of its length.

3. The stent graft for in situ fenestration of the aortic arch according to claim 1, characterized in that: The number of the distal Z-wave bracket ring groups is 3-4, and the distal Z-wave bracket ring groups are all covered with a film. The spacing between the Z-wave bracket rings of the distal Z-wave bracket ring group is 1mm-20mm, the wave amplitude of the Z-wave bracket ring of the distal Z-wave bracket ring group is 5-20mm, and the metal wire diameter of the distal Z-wave bracket ring group is 0.3-1.0mm.

4. The stent graft for in situ fenestration of the aortic arch according to claim 1, characterized in that: The coating material is eptfe, i.e. expanded polytetrafluoroethylene film, the coating thickness is 0.2-1.0mm, the mesh reinforcement wire material is eptfe with higher strength, and the mesh size of the mesh reinforcement wire is 5*5-10*10mm.

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