A NEW ASPECT OF CORONARY-ARTERY SPASM INDUCED BY CARDIAC-SURGERY

Five patients developed coronary artery spasm during open heart surgery in our institute between 1984 and 1988. One patient was undergoing coronary artery bypass grafting and the other four valvular surgery or surgery for congenital heart disease. In one of the patients undergoing non-coronary surgery, the preoperative induction of right coronary artery spasm by ergonovine had been documented angiographically while the remaining three patients did not possess organic or functional coronary disease. All five patients exhibited a sudden onset of hemodynamic collapse with ventricular tachyarrhythmias or ST elevation during the early period of reperfusion, the time to onset being 89.2 +/- 84.8 minutes after unclamping of the aorta. In addition, contraction of the right ventricular free wall was severely impaired. Although one patient died due to left ventricular rupture caused by direct cardiac massage, the early mortality thus being 20 per cent, the other four were successfully treated with the intravenous administration of nitroglycerin and diltiazem. Three patients required the assistance of intraaortic balloon pumping for severe cardiac failure. Thus, during open heart surgery, coronary artery spasm can occur even in patients without organic coronary lesions and the possible mechanisms of this condition are discussed herein.