Stents (wire props) are placed within narrowed (stenotic) or blocked (blood clotted) coronary arteries that feed the heart with oxygenated blood over 2 million times a year in the U.S., mostly among men and women with angina chest pain.
The use of a coronary artery stent may sometimes be worse than the patient's disease. The history of coronary artery stenting is one of presumed effectiveness. Stent-induced heart attacks and deaths have plagued this widely practiced intervention since its inception.
Since 1986 when the first stent (a cylindrical metallic wire device to prop open narrowing arteries that supply the heart to oxygenated blood) was implanted, it was presumed these implants were obviously effective. The Food & Drug Administration didn't officially approve of these devices till 1994.
Given that stents do not address the cause of coronary artery disease, it is not surprising to learn of their many drawbacks.
The need for stents became apparent after balloon angioplasty that involves the insertion of a wire with a balloon tip into coronary arteries. The balloon is inflated to break up a clot in a narrowed artery. Following balloon angioplasty, rebound occlusion occurred in 5-10% of patients within minutes to hours immediately following the procedure.
Today many stents are placed in coronary arteries solely based upon symptoms of sometimes incapacitating chest pain (angina).
Stents do not completely eliminate re-stenosis, that is, recurrence of arterial narrowing, and in-stent closure or collapse is reported. In fact, within-stent narrowing (re-stenosis) is as high as 20-30% of treated cases of angina.
Drug-eluting stents then were developed to overcome that problem but long-term follow-up revealed cases of stent thrombosis (stent-induced blood clots) which is now known to induce a severe heart attack in 50% of stents that do form thrombi with an accompanying 20% mortality rate. So anti-blood clotting therapies (aspirin, heparin, warfarin) were then employed with stenting, but this led to high rates of bleeding episodes that require long hospital stays.
The use of stents has grown to the point of absurdity. One patient had 67 stents placed in his heart. The patient's angina persisted and his cardiologist just kept implanting stents in an effort to relieve the unremitting pain. Where does this insanity stop?
All is not so happy in the land of coronary artery stents.
By 2007 the COURAGE trial shocked the cardiology profession. Stenting was no better than optimal drug therapy (aspirin, statins, blood thinners). Stenting did not reduce the rate of heart attack or death compared to medicines alone. This finding persisted through 15 years of follow-up. But the use of stents continued to rise exponentially.