Is drug-eluting stents safe?

The article was professionally consulted with Specialist Doctor II Nguyen Quoc Viet - Interventional Cardiologist - Department of Medical Examination & Internal Medicine - Vinmec Danang International General Hospital.

Drug-eluting coronary stents represent a major advance in interventional cardiology. Drug-eluting stents help limit restenosis in patients with significant coronary artery stenosis. However, the use of drug-eluting stents increases the risk of stent thrombosis and increases the risk of anticoagulation-induced bleeding.

A coronary stent is a highly abrasion and oxidation resistant metal stent placed in the lumen of a coronary artery, for the purpose of recanalizing or widening the narrowed coronary lumen and keeping it from narrowing again.
Drug-coated coronary stents are coated with a special drug to prevent endothelium growth. This class of drug will be released gradually into the blood vessels after stenting, keeping the lumen always smooth and reducing the rate of coronary artery re-stenosis after the intervention.

There are four types of coronary stents:
Common metal stents are also known as bare metal stents. This is a first-generation coronary stent, without a drug coating. The possibility of coronary re-stenosis after bare metal stenting is quite high, about 20-25% of patients, within 6 months after placement.

Drug-eluting stents are coronary stents that are coated with drugs (first-generation stents: sirolimus, paclitaxel; second-generation stents: everolimus, zotarolimus) on the surface of a metal framework to prevent vascular endothelium from increasing overbirth to reduce the risk of restenosis in the stent. The rate of coronary restenosis with drug-eluting coronary stents is approximately 10%, significantly lower than with conventional metal stents.` Drug-eluting stents such as:
First-generation drug-eluting stents: Taxus (Paclitaxel coated) and Cypher (Sirolimus coated). Many studies have shown that the indigestible polymer layer of first-generation drug-eluting stents can cause delayed hypersensitivity reactions, chronic inflammation, accumulation of fibrin fibers and consequent poor endothelialization of the vessel wall and thrombosis in the stent. Compared with bare metal stents, first-generation drug-eluting stents showed no difference in mortality, but increased the risk of late stent thrombosis. Second-generation drug-eluting stents: further advances in design. The second-generation drug-eluting stent framework is thinner (mostly made of Cobalt Chromium alloy) and the drug-carrying polymer layer is either absorbable or bioavailable. This type of stent is safer because of a significant reduction in early and late stent thrombosis compared with non-drug-eluting stents and other drug-eluting stents. Absorbent stent (biological stent): is a drug-eluting stent with a completely self-absorbable framework after a period of stent placement, which promotes vascular remodeling and the coronary artery will return to its normal biological characteristics, such as: : elasticity, coronary artery reconstruction, after self-dissolving does not obstruct the lateral branch, the soft frame makes blood flow easier at the corner, reducing the reaction of blood vessels at the beginning and end of the stent. In initial studies, self-absorbable drug-eluting stents demonstrated clinical outcomes comparable to second-generation drug-eluting stents. However, the cost of this type of stent is very high.
Dual therapy stents: is the newest drug-eluting coronary stent that reduces the risk of restenosis and thrombosis in the stent, promoting wound healing. With those advantages, dual therapy stents are the type of stents. most expensive drug coverage.

Drug-eluting coronary stents represent a major advance in interventional cardiology. More and more patients are being treated successfully and prolonging life with drug-eluting stents. However, the following precautions should be taken if the patient is given a drug-eluting stent:
Drug-eluting stents carry the risk of intravascular thrombosis. Although new-generation stents have many advantages over older-generation stents, the risk of stent thrombosis and restenosis after stenting is still possible. Stent thrombosis is an acute complication that can occur early or late after coronary stenting and has a high mortality rate. To prevent the risk of blood clot formation, patients need to take antiplatelet drugs such as aspirin, clopidogrel, .. regularly and do not quit on their own. Many large studies in the UK and the US have shown that smoking cessation is strongly associated with restenosis and increased mortality. However, prolonged use of antiplatelet agents is associated with an increased risk of bleeding, especially gastric bleeding. The risk of bleeding is increased if the patient has a history of peptic ulcer disease or other bleeding disorders. Drug-eluting stents only limit but not completely prevent coronary re-stenosis. Therefore, although the rate is very low, coronary re-stenosis after a period of drug-eluting stents can still occur, especially in patients who do not take medication regularly. With adequate and appropriate medical treatment, drug-eluting stents are relatively safe and prolong life for patients. Coronary stenting technique has been implemented at Vinmec International General Hospital with a success rate of up to 98%. The technique is performed by a team of highly qualified cardiologists with many years of experience in the profession. With a modern cath lab system, sterile medical equipment, and a quiet space, it helps patients recover quickly and minimize risks after stenting.
Cardiovascular Center - Vinmec International General Hospital is also applying very effectively and safely techniques of coronary angiography, balloon angioplasty, angioplasty and coronary stenting; meet the needs of timely and effective examination and treatment of acute diseases such as acute myocardial infarction, cardiogenic shock, bradyarrhythmias requiring emergency medical equipment.