A quantification of different forms of acute myocardial necrosis, myocardial leukocytic infiltrates and myocardial fibrosis was accomplished in 26 chronic cocaine abusers who died of cocaine intoxication and compared to 45 normal subjects who died from head trauma and 38 who died of acquired immunodeficiency syndrome. The findings were: absence of infarct necrosis, a similar frequency and extent of coagulative myocytolysis (contraction band necrosis) and leukocytic infiltrates in cocaine abusers and normal controls, and an absence of myocardial fibrosis in cocaine abusers. These findings question both the acute and chronic cardiotoxicity of cocaine. The infarct-like pattern in some predisposed subjects may be due to an excess of catecholamine release induced by the drug resulting in coagulative myocytolysis and platelet thrombi.