Carmustine (BCNU), a nitrosourea derivative, is an antineoplastic agent used recently for the treatment of human solid tumors and lymphomas in high doses with autologous bone marrow transplantation. Cardiac toxicity related to BCNU has not been described well. Three patients are reported without a history of angina pectoris who had clinical and electrocardiographic evidence of myocardial ischemia during and immediately after BCNU infusion. The incidence, cause, and mechanism of such a side effect are unknown but should be considered in patients receiving high-dose carmustine infusions.