The clinical and angiographic variables of 26 coronary artery disease patients at the University of Alberta Hospitals requiring emergency coronary artery bypass grafting (CABG) for failed percutaneous transluminal coronary angioplasty (PTCA) were reviewed. Emergency CABG was judged necessary in 2% of 1300 consecutive patients undergoing PTCA. The most frequent indication for an emergency operation was dissection and acute closure of eccentric bend point target lesions associated with clinically severe, unremitting chest pain and ST-T abnormalities suggestive of impending myocardial infarction. The mortality rate for the combined procedures of failed PTCA and CABG was low (3.8%). The incidence of periprocedural infarction was high (61%); it was, however, associated with a benign clinical course and electrocardiographic evidence of significant reversibility of acute phase damage. Thus, overall, emergency CABG appears to be a clinically efficacious treatment for patients with threatened or impending infarction as a consequence of failed PTCA.