Angioplasty the surgical technique for unblocking arteries is not quite the modern wonder of the medical world it has been claimed to be.

The survival rate among patients in the first year is lower than those who had major bypass surgery, and often requires a second operation within the year to clear the arteries again. Angioplasty patients will also need to be on more medication than those given a bypass.

Although doubts about angioplasty have been on the increase in the last couple of years, the absolute proof has come in the world's major study into the relative benefits of angioplasty and bypass surgery.

The study, known as CABRI, looked at the benefits over the first year. Another study, carried out by the London School of Hygiene, found that angioplasty patients who could survive the first year had as good a chance of survival as bypass patients.

The CABRI trial involved 1,054 patients selected from 26 heart centres around Europe. Of these, 513 angina patients had coronary bypass surgery, and 541 had angioplasty.

After one year, 2.7 per cent of bypass patients had died, compared to 3.9 per cent of those given angioplasty. This means that angioplasty patients are 1.42 times more likely to die within the first year than bypass patients.

More people in the angioplasty group also needed a further operation in the first year than did the bypass group. Only 66 per cent of the angioplasty group reached the end of the first year without having further medical intervention, compared with 93.5 per cent of the bypass group.

Angioplasty patients were also given more medication, and were more likely to suffer major angina after treatment.

The London School of Hygiene trial involved 3,371 patients, 1,661 of whom had bypass surgery and 1,710 angioplasty. Like the CABRI trial, it discovered that angioplasty patients faced a 1.08 times greater risk of dying than bypass patients, and that 17.8 per cent needed additional surgery within the first year. After that, the rate fell to just 2 per cent.

The finding is a significant blow to angioplasty, which was seen as a major step forward in heart treatment because it is far less traumatic than bypass surgery, is less expensive and is easier to perform with fewer complications (see WDDTY, vol 4, no 2).

Surgeons must reveal these facts to the patient before any treatment is started, the CABRI report concludes (The Lancet, November 4, 1995).