The efficacy of drug-coated stents and bare metal stents is different. With drug-coated stents, it is necessary to take two antiplatelet drugs orally for a longer period of time, such as aspirin+Bolivir or aspirin+Tiglitazarol. With bare metal stents, oral administration of two antiplatelet drugs for 1 year is also advocated. The difference is that after implantation of a bare metal stent, the endothelium can grow onto the surface of the bare metal stent more quickly because there are no drugs to inhibit the growth of the endothelium. the vast majority of the stent can be covered by endothelium in about 1 month, and by 3 months the stent is more completely covered by endothelium.
Two, bare metal stents and drug-eluting stents which is better
In fact, now in the clinic is almost all drug-coated stents, the era of bare metal stents is over, but can not simply evaluate which is better, they are in the treatment of the heart class of the basic road of merit.
Cardiac intervention technology has now gone through three eras, and is now moving toward the epoch of biodegradable stents, but of course the future is bright and the road is bumpy, and at present, biodegradable stents are still encountering certain difficulties. You can come together to review the development of cardiac intervention, strictly speaking, the era of coronary intervention, because there are many cardiac interventions.
(I) Balloon dilatation
The first case of balloon dilatation was done in 1977, but then it was observed that there were serious problems with balloon dilatation:
1. After balloon dilatation, restenosis is likely to occur, and the restenosis rate reaches 30%-50%.
2. During balloon dilatation, it may lead to vessel tearing and vascular occlusion, resulting in acute myocardial infarction.
(2) Improvements were made and bare metal stents were used
Bare metal stenting became safer. It is safer than balloon dilatation, when a blockage occurs in a blood vessel. Immediately holding the vessel open with a stent relieves the danger, but the stenosis rate is about 10-20%.
(C) Continued improvement with drug-coated stents
Drugs that inhibit cell proliferation are coated onto the stent so that the drugs can be slowly released about 3 months after the stent is implanted, keeping the stent open and preventing restenosis from occurring, and the restenosis rate of drug-coated stents is only 5-10%.
(D) Continue to improve and use biodegradable stents
There are currently two main types of drugs used in drug-coated stents, rapamycin and paclitaxel, and the vast majority of stents currently use rapamycin, or a derivative of rapamycin. Drug-coated stents require longer oral doses of two dual antiplatelet drugs, aspirin + clopidogrel or tegretol, for a minimum of a year to a year and a half.
Are bare metal stents completely out of the history books? For the time being, no, because the bare stent has its own strengths, some patients suffer from other diseases, urgent need for surgical treatment, but at the same time found to have coronary artery disease, can only be put stent treatment, such a situation the vast majority of cases to be put on the metal bare stent, stent implantation can be discontinued 1-3 months after the use of dual antiplatelet drugs, and wait until after the completion of surgical procedures and then carry out antiplatelet therapy. In conclusion, for most patients who need stents, the first choice of drug-coated stents, but for individual special patients, we still use bare stents.