A case of variant angina and myocardial infarction 6 months after successful bypass surgery.

A 61-year-old man with variant angina underwent bypass surgery to the left anterior descending artery (LAD) which had a 90% narrowing in the proximal segment. The postoperative course was favorable, but 6 months after surgery, the calcium antagonist, diltiazem, with which the patient had been continuously treated since surgery, was stopped because of hepatitis. Immediately after discontinuation of the calcium antagonist, the patient had an acute anterior myocardial infarction. An angiogram demonstrated a patent graft and an anteroapical infarction. The infarction is thought to have been caused by a severe, prolonged spasm of the LAD distal to the graft or diffuse spasm of the LAD throughout its entire length. Thus, after bypass surgery calcium antagonists should be given continuously to patients with variant forms of angina pectoris.