Covered stent and preparation method thereof

Abstract

The invention provides a covered stent and a preparation method thereof. The covered stent comprises a stent body and a covered pipe material which sleeves the stent body, wherein the covered pipe material is in a retracted state and is fitted to an outer surface of the stent body; the covered pipe material can be tightly fitted to the surface of the stent without the need of additional sewing and spinning processes and the like; one covered pipe material can be applicable to stents with different specifications, so that the applicability of the covered stent is improved; only one layer of the stent and one layer of the covered pipe material are adopted, so that the outer diameter size of the covered stent is small and the trafficability and smoothness of the covered stent are improved. The invention further provides the preparation method of the covered stent; the stent body, which is sleeved with the covered pipe material, is put into a medium with pre-set temperature, and the covered pipe material is retracted and fitted to the outer surface of the stent body, so that the covered stent can be prepared before surgeries; multi-specification goods preparation is not needed, and the cost of clinical goods preparation is low.

Description

technical field [0001] The invention relates to the technical field of medical devices, in particular to a covered stent and a preparation method thereof. Background technique [0002] Common vascular diseases include aneurysms, ruptured blood vessels, perforated blood vessels, and narrowed blood vessels. Aneurysm is caused by the thinning of arterial wall due to disease, injury or congenital factors. Under the impact of blood flow, the weak blood vessel gradually protrudes outward into a circular shape, and then becomes an aneurysm, which will compress the surrounding tissue organ. Moreover, the continuous growth of the aneurysm may cause the rupture of the aneurysm blood vessel, acute bleeding, and life-threatening. [0003] Endovascular interventional therapy has the advantages of less trauma, less complications, high safety, and less pain for patients, and has gradually become the main method for aneurysm treatment. Among them, the stent graft method is a commonly use...

AI Technical Summary

Problems solved by technology

In addition, because most of the stents are permanent stents, the PTFE covering material exists in the coronary artery for a long time, which will lead to occlusion of the side branch of the coronary artery perforation site.

More importantly, due to the barrier of PTFE membrane, it cannot effectively adhere to endothelial cells and induce cell differentiation, which limits the endothelialization of the scaffold, triggers endothelial exfoliation, and leads to platelet aggregation, inflammatory response, proliferation and migration of vascular smooth muscle cells, and extracellular matrix. Formation of a series of pathological reactions, and may increase the risk of delayed thrombosis

Clinical studies have found that the restenosis rate of implanted PTFE stents is higher, which is similar to that of bare metal stents. Therefore, the incidence of thrombosis is higher, and the time of antiplatelet therapy needs to be prolonged after implantation, and the stents are expensive.

In addition, since the PTFE membrane is generally connected to the stent by suturing, it is difficult to suture small-sized stents technically, and small-diameter blood vessels are the most prone to sudden diseases such as coronary perforation

However, for large vessel diameters, cath labs are usually equipped with stents of different diameters and lengths according to the diameter and length of the blood vessel, resulting in high clinical stocking costs, resulting in most cath labs not being able to equip suitable stent grafts. Failure to provide effective and timely treatment in an emergency

[0010] 2) Autologous vascular covered stent, which is taken from the autologous vein and fixed on the stent with sutures, and then released at the perforation site through percutaneous intervention to achieve the effect similar to the covered stent. Its advantages are good biocompatibility, rapid endothelialization, and disadvantages The operation is time-consuming, the surgical trauma is large, and the outer diameter of the stent before expansion is large, so a large-lumen guiding catheter is required

However, due to the existence of two layers of coating, there are also poor flexibility of the stent, the outer diameter of the stent before expansion is large, the specifications are incomplete, there is a lack of small diameter specifications, and the cost of stocking is expensive, etc., and the problem of blockage of the opening of the side branch of the blood vessel cannot be solved.

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