Between July 1980 and November 1982, there were 935 coronary angioplasties attempted at Emory University Hospital. Of these patients, 20 developed acute occlusion. Of these 20, 19 presented within 3 hr of surgery or within 3 hr after stopping a continuous heparin infusion. Five patients required emergency surgery, but in 15 nitrates, nifedipine, and/or repeat angioplasty reopened the artery and...