At present, the thickness of stents used in clinic is relatively small. After surgical implantation, with the growth and healing of vascular endothelial cells, the stent is covered by vascular endothelium and cannot be taken out after implantation.
Supplementary knowledge:
Cardiac stent, also known as coronary stent, is a commonly used medical instrument in cardiac interventional surgery, which has the function of dredging arterial blood vessels. Heart stent first appeared in 1980s, and experienced the development of metal stent, coated stent and soluble stent. The main materials are stainless steel, nickel-titanium alloy or cobalt-chromium alloy. China is a big market for cardiac interventional surgery. However, on June 4th, 20 12, 10, Hu Dayi, a famous cardiovascular expert, said at the 23rd Great Wall International Cardiology Conference that half of the cardiac stents were unreliable and the profit was nine times. The materials used for heart stents are stainless steel, nickel-titanium alloy or cobalt-chromium alloy, and different types of stents have different structures.
Duration of use
Restenosis can occur 6 ~ 8 months after stent implantation, that is to say, restenosis can occur in the stent. The incidence of restenosis is about 20% (15% ~ 40%) at the initial stage of metal stent use. In the era of drug stent, the incidence of restenosis dropped to about 9%. If coronary angiography is reviewed half a year after operation, there is no in-stent restenosis, generally speaking, restenosis will rarely occur in the future. But that doesn't mean there will be no more narrowness. The reason for this situation is not necessarily entirely due to the stent itself. If after stent implantation, patients fail to take medicine, change their unhealthy lifestyle, and their blood pressure, blood lipid and blood sugar are not well controlled, then the original normal blood vessels may produce new lesions and restenosis at the stent site.