Switchable aortic fenestration stent

Abstract

This invention discloses a "switchable" aortic fenestration stent, specifically relating to the technical field of medical devices. The "switchable" aortic fenestration stent includes a main stent, a covered local tubular structure, and a support extension arm switching structure. The main stent is composed of a metal support and a covering. The covered local tubular structure forms a potential channel connecting the inside and outside of the stent. The support with the extension arm controls the opening and closing of the covered tubular structure by retracting and releasing, providing a channel for establishing stent branches. This invention allows for adjustment of the number of fenestrations and does not require precise alignment of the fenestration sites, simplifying the branch stent reconstruction process.

Description

Technical Field

[0001] This invention relates to the technical field of medical devices, and in particular to a "switchable" aortic fenestration stent. Background Technology

[0002] Aortic dissection and aneurysm are serious diseases that threaten people's lives. Rupture of aortic dissection and aneurysm can lead to sudden death. Currently, the mainstream treatment for aneurysms is minimally invasive intraluminal placement of a covered stent to isolate the diseased artery. However, lesions involving aortic branches, such as the brachiocephalic artery in the neck, the left common carotid artery, the left subclavian artery, and the visceral arteries in the abdominal cavity, present greater challenges because the covered stent will cover the branch vessels.

[0003] Currently, there are several methods for treating branched blood vessel sites:

[0004] 1. Chimney stent technique, which involves inserting a covered stent into a branch vessel, parallel to the main stent within the aorta. The chimney stent creates a blood flow channel outside the main stent to flow into the branch vessel. Its biggest problem is the complication of endoleak around the covered stent.

[0005] 2. Window opening technology: including external pre-windowing and internal in-situ windowing technology.

[0006] The pre-fenestration technique involves pre-cutting an opening outside the body at the site corresponding to the branch vessel of the covered stent, ensuring the opening aligns perfectly with the branch vessel during deployment. A drawback of this technique is that the pre-fenestration site and the branch vessel opening may not align precisely, potentially resulting in incomplete coverage of the branch vessel opening. This risk is even greater when multiple fenestrations are present for multiple branch vessels.

[0007] In-situ fenestration is primarily used for the reconstruction of the three branch vessels in the neck. This technique involves placing a covered stent in the aorta, then puncturing the stent via a branch vessel using a laser or a sharp guidewire. Balloon dilation is used to expand the stent cover before inserting the branch stent. The main challenges of this technique are the difficulty of puncturing through the branch vessel, the risk of aortic damage from the guidewire or laser leading to massive bleeding, and the need to establish an alternative pathway to maintain blood supply to the head. This increases the risk of intraoperative cerebrovascular accidents, making the procedure lengthy and complex.

[0008] 3. Commercialized branch support

[0009] Currently, there are no fully mature branch stents. COOK has launched an abdominal aortic fenestration stent, which requires preoperative measurement of the location of the visceral vessel openings in the abdominal aorta for customization by the manufacturer. Due to its complexity in manufacturing and long waiting time, this product is not widely used clinically. Several branch stents for the thoracic aorta are also available abroad. The commercially available thoracic aortic branch stent in China is the Caster stent, a single-branch stent designed to connect a branch covered stent to a main covered stent. A common drawback of branch stents, both domestic and international, is their poor versatility; different stent models are required for single-branch, two-branch, and three-branch reconstructions. Summary of the Invention

[0010] The present invention aims to provide a "switchable" aortic fenestration stent, which solves the problem that existing aortic endovascular stent grafts lack commercially available branch stents, and clinical practice can only perform non-standard branch vessel reconstruction, resulting in difficult surgery and high complication rates.

[0011] To achieve the above objectives, the technical solution of the present invention is as follows: a "switch-type" aortic fenestration stent, comprising a main stent, a covered local tubular structure, and a support extension arm switch structure. The main stent is composed of a metal support and a covering membrane disposed within the metal support. The covered local tubular structure is sutured to the inner wall of the covering membrane, forming a potential channel connecting the inside and outside of the stent. The support extension arm switch structure connects to the covered local tubular structure, and the support extension arm switch structure regulates the opening and closing of the covered local tubular structure by retracting and releasing.

[0012] Furthermore, the number of the coated local tubular structures is three, and the three coated local tubular structures are located on the same axis.

[0013] The above setup can be used for the reconstruction of branch vessels in the thoracic aorta.

[0014] Furthermore, the number of the coated local tubular structures is three, and the three coated local tubular structures are distributed in an isosceles triangle, with the coated local tubular structure located at the vertex of the isosceles triangle positioned in the center of the main support.

[0015] The above setup can be used for the reconstruction of renal arteries and superior mesenteric arteries, branches of the abdominal aorta.

[0016] Compared with existing technologies, the beneficial effects of this solution are:

[0017] 1. This solution has a simple structure and the branch reconstruction operation is simple and easy to perform. The "switch-type" channel can reconstruct different numbers of branches as needed, and can also be used as a general-purpose covered stent without branches, which has good versatility.

[0018] 2. This solution addresses the lack of commercially available fenestrated aortic stent grafts, which necessitates non-standardized branch vessel reconstruction in clinical practice, leading to difficult surgeries and high complication rates. It also overcomes the challenges posed by the complex structure and difficult operation of currently under-development branched aortic stents. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the "switch-type" aortic fenestration stent of Example 1;

[0020] Figure 2 This is a schematic diagram of the "switch-type" aortic fenestration stent in Example 1 when it is partially released;

[0021] Figure 3 This is a schematic diagram of the branch stent placed into the "switch-type" aortic fenestration stent in Example 1;

[0022] Figure 4 This is a schematic diagram of the structure of the "switch-type" aortic fenestration stent in Example 1 when it is fully deployed and cooperates with the branch stent;

[0023] Figure 5 This is a schematic diagram of the "switch-type" aortic fenestration stent in Example 2;

[0024] Figure 6 This is a schematic diagram of the fenestrated stent used in the thoracic aorta according to Example 2;

[0025] Figure 7 This is a schematic diagram of the "switch-type" aortic fenestration stent in Example 3;

[0026] Figure 8 This is a schematic diagram of the fenestrated stent of Example 3 applied to the abdominal aorta. Detailed Implementation

[0027] The present invention will be further described in detail below through specific embodiments:

[0028] The reference numerals in the accompanying drawings include: 1. Covered partial tubular structure; 2. Support extension arm switch structure; 3. Supporting metal unit; 4. Cover; 5. Inner hole; 6. Outer hole; 7. Branch bracket.

[0029] Example 1

[0030] like Figures 1 to 4As shown, the "switch-type" aortic fenestration stent includes a main stent, a covered local tubular structure 1, and a support extension arm switch structure 2. The main stent consists of multiple spaced-apart metal supports and a covering 4 covering the metal supports. The covered local tubular structure 1 is a long tubular covering structure sutured to the inner wall of the covering 4, forming a local tubular structure in the covering 4. This structure forms an inner hole 5 leading into the lumen and an outer hole 6 leading out of the wall. A subsequent metal support on the main stent forms a support extension arm switch structure 2, extending to below the preceding metal support and sutured to the covered local tubular structure 1. When the preceding metal support unfolds and the subsequent metal support connected to the support extension arm switch structure 2 retracts, the covered local tubular structure 1 opens, and the inner hole 5 and outer hole 6 open to form a potential channel connecting the inside and outside of the stent. A branch stent 7 can be inserted through this channel, and the branch stent 7 can be released to establish a branch.

[0031] Example 2

[0032] As attached Figure 5 and Figure 6 As shown, the "switch-type" aortic fenestration stent includes a main stent, a covered local tubular structure 1, and a support extension arm switch structure 2. The main stent consists of multiple spaced-apart metal supports and a covering membrane 4 covering the metal supports. The covered local tubular structure 1 is a long tubular covering structure sutured to the inner wall of the covering membrane 4, forming a local tubular structure in the covering membrane 4. This structure forms an inner hole 5 leading into the lumen and an outer hole 6 leading out of the wall. A subsequent metal support on the main stent forms a support extension arm switch structure 2, extending to below the preceding metal support and sutured to the covered local tubular structure 1. When the preceding metal support unfolds and the subsequent metal support connected to the support extension arm switch structure 2 retracts, the covered local tubular structure 1 opens, and the inner hole 5 and outer hole 6 connect, forming a potential channel communicating between the inside and outside of the stent. A branch stent 7 can be inserted through this channel, and the branch stent 7 can be released to establish a branch. In this embodiment, there are three local tubular structures 1 covered with film, and the three local tubular structures 1 covered with film are located on the same axis.

[0033] The fenestrated stent of this embodiment can be applied to the establishment of branch vessels of the thoracic aorta. The procedure for inserting the branch stent 7 is the same as in Embodiment 1.

[0034] Example 3

[0035] As attached Figure 7 and 8As shown, the "switch-type" aortic fenestration stent includes a main stent, a covered local tubular structure 1, and a support extension arm switch structure 2. The main stent consists of multiple spaced-apart metal supports and a covering 4 that covers the metal supports. The covered local tubular structure 1 is a long, tubular covering 4 structure sutured to the inner wall of the covering 4, forming a local tubular structure within the covering 4. This structure forms an inner hole 5 leading into the lumen and an outer hole 6 leading out of the wall. A subsequent metal support on the main stent forms a support extension arm switch structure 2, extending to below the preceding metal support and sutured to the covered local tubular structure 1. When the preceding metal support unfolds and the subsequent metal support connected to the support extension arm switch structure 2 retracts, the covered local tubular structure 1 opens, and the inner hole 5 and outer hole 6 connect, forming a potential channel communicating between the inside and outside of the stent. A branch stent 7 can be inserted through this channel, and the branch stent 7 can be released to establish a branch.

[0036] There are three membrane-coated local tubular structures 1, which are distributed in an isosceles triangle, and the membrane-coated local tubular structure 1 located at the vertex of the isosceles triangle is positioned in the center of the main support.

[0037] The fenestrated stent of this embodiment can be applied to the establishment of branch vessels in the abdominal aorta. The procedure for inserting the branch stent 7 is the same as in Embodiment 1.

[0038] The above are merely embodiments of the present invention, and common knowledge such as specific structures and / or characteristics in the solutions are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A "switchable" aortic fenestration stent, characterized in that: The device includes a main support frame, a membrane-covered partial tubular structure, and a support extension arm switch structure. The main support frame consists of a metal support body and a membrane disposed within the metal support body. The membrane-covered partial tubular structure is sewn onto the inner wall of the membrane, forming a potential channel connecting the inside and outside of the support frame. The support extension arm switch structure connects to the membrane-covered partial tubular structure, and the support extension arm switch structure controls the opening and closing of the membrane-covered partial tubular structure by retracting and releasing.

2. The "switchable" aortic fenestration stent according to claim 1, characterized in that: The number of the coated local tubular structures is three, and the three coated local tubular structures are located on the same axis.

3. The "switchable" aortic fenestration stent according to claim 1, characterized in that: The number of the membrane-coated local tubular structures is three, and the three membrane-coated local tubular structures are distributed in an isosceles triangle, with the membrane-coated local tubular structure located at the vertex of the isosceles triangle positioned in the center of the main support.

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