Up to one-third of all coronary bypass surgery may be unnecessary, and could even be hastening the death of the patient.
Researchers from 14 major heart hospitals around the world have concluded that the procedure may not be appropriate with patients at low risk of suffering a fatal heart attack.
Their conclusion is based on seven randomized trials that have studied the effectiveness of the procedure between 1972 and 1984. Of those who took part in the trials, about one-third were low-risk cases.
While there was inadequate data to make a conclusion, there was evidence that those patients would have lived longer if they had received drugs therapy rather than surgery.
Research team leader Prof Yusuf Zucker from the Hamilton General Hospital in Ontario, Canada said the data overwhelmingly supported the view that bypass surgery improves the chances of survival over general medical management with patients in high and medium-risk categories. It is also a more effective procedure among patients with left main artery disease (The Lancet, 27 August 1994).
Balloon angioplasty has longer-lasting benefits if implants called stents are fitted into the arteries during the operation.
Angioplasty is a relatively new procedure which involves the threading of a tiny "balloon" through the arteries, thus expanding them and pressing fatty plaques against the coronary wall (see WDDTY, vol 4, no 2).
Unfortunately, stenosis or the narrowing of the artery can reoccur within six months.
Researchers from a number of European heart centres have concluded,
after carrying out research among 520 heart patients, that stenosis is less likely to happen if a stent is fitted. Stents keep the coronary
However, stents also increased the risk of complications, necessitating longer hospital stays.
The study group decided that these drawbacks may prevent stents from becoming an accepted part of the procedure. (New Eng J Med, 25 August, 1994).