[Coronary spasm as a mechanism of ischemia or myocardial necrosis immediately after coronary surgery. Considerations on 5 cases and review of the literature].

Several recent reports suggest that coronary artery spasm may represent a major complication of coronary artery bypass surgery, and that it may have gone unrecognized in the past. During a three-year interval ending July 1983 we have encountered 5 cases in whom reversible S-T changes, angina, arterial hypotension, major arrythmias and/or angiography prompted the diagnosis of coronary arterial spasm early after aorto-coronary bypass surgery. Our experience and the review of 15 previously reported cases reveals that in most cases the clinical presentation was that of an acute, severe, ischemic cardiac event that occurred few hours after termination of cardiopulmonary bypass. A more benign course took place in a minority of cases, although some of them showed evidence of myocardial necrosis on ECG and/or left ventriculography. The mortality rate in the collective series was 20%, and the rate of perioperative non fatal myocardial infarction was 25%. Glyceryl trinitrate administration into the ascending aorta or into the spastic coronary artery appeared to be the most effective way of treating this condition, while the same drug was seemingly uneffective when administered intravenously. The use of calcium antagonists was associated with a favourable outcome in some patients, but on the whole the results were unpredictable. Prompt consideration of the possibility of coronary artery spasm and aggressive treatment are required in order to minimize its impact on perioperative mortality and morbidity rates.