Aortocoronary bypass operation as an emergency intervention after transluminal coronary angioplasty. Which factors prevent the incidence of a major infarct?

Abstract

Among 830 patients in whom transluminal coronary angioplasty (TCA) was undertaken there were 41 (4.9%) who required an aortocoronary bypass operation for acute complications (vessel dissection with markedly reduced flow; complete occlusion or contrast-medium extravasation). The group of 41 was divided into two, based on angiography (25) or ECG (16) criteria. Group 1 comprised 30 patients, who developed no or only a small infarct peri-operatively; group 2 had eleven patients with large infarcts. The patients of group 1 had a greater exercise tolerance pre-operatively than those of group 2 (118 +/- 28 vs 91 +/- 45 Watt; P less than 0.05) and had a higher revascularization time (interval between end of the cardiac catheterization and onset of reperfusion: 154 +/- 58 vs 264 +/- 173 min; P less than 0.05). Collaterals to the area supplied by the treated vessel were observed only in group 1 patients (10), but not of those in group 2. Age, history of previous infarction, number of diseased coronary arteries, ischaemic reaction during ergometry, initial left-ventricular ejection fraction and symptoms after onset of complications were without significance. It is concluded that an aortocoronary bypass operation should be performed as early as possible after post-TCA vascular complication in order to prevent the development of larger infarcts.