stent graft

Abstract

A covered stent comprising a supporting structure and a covering film coated on the supporting structure; wherein the covering film is composed of at least two layers of allogeneic decellularized tissue matrix membranes, and the smooth surface of each layer of matrix membrane faces the supporting structure. The rough side faces outward; the adjacent two layers of matrix membrane are arranged in such a way that the growth direction of collagen fiber bundles intersects to form a certain angle. Among the at least two layers of allogeneic decellularized tissue matrix membranes, except for the innermost matrix membrane, the other matrix membranes are provided with multiple perforations, and the pore diameter gradually increases from the inner layer to the outer layer. Adopting the covered stent of the present invention can effectively reduce the formation of thrombus and endothelial hyperplasia; can effectively enhance the strength of the covered film and can reduce the axial contraction of the covered film when the covered stent is released; can effectively adhere to endothelial cells to promote cell differentiation to promote Tissues and blood vessels grow in, accelerating the endothelialization of the aneurysm lesion, so as to achieve a more effective treatment of aneurysm disease.

Description

technical field [0001] The invention relates to medical equipment, in particular to a covered stent. Background technique [0002] Aneurysm is caused by the partial weakening of the arterial wall due to disease, injury or congenital factors. Under the impact of blood flow, the weak point of the arterial wall protrudes outwards and gradually expands to form. Round, oval, or prismatic cystic enlargement. An aneurysm is a potentially life-threatening condition in which the aneurysm grows continuously under the impact of blood flow, compressing surrounding organs or tissues and causing symptoms. Rapid bleeding occurs when an aneurysm ruptures due to increased blood pressure or other factors. Aneurysms can occur in different parts of the body, the most common being abdominal aortic aneurysms and intracranial aneurysms. In order to avoid the high risk of surgery, endovascular interventional therapy has gradually become the main method for treating aneurysms. Endovascular interv...

AI Technical Summary

Problems solved by technology

Among them, the former has poor biocompatibility and cannot be degraded by the human body, and it will cause serious inflammatory reactions when implanted in the human body; the latter has better biocompatibility, but poor mechanical properties, and the surface porosity is low, so it is difficult to Facilitate cell attachment and proliferation and delay endothelialization and healing of lesions

The structural strength of the single-layer film is poor, and the film is easily damaged during the process of crimping, releasing, and bending of the stent graft. In addition, due to the single-layer film pore structure, the film will be stretched when the stent is released. , the void structure is deformed so that the phenomenon of axial shortening is prone to occur, which eventually leads to the inability to completely cover the lesion, etc.

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