A 66-year-old woman presented with new-onset complete left bundle branch block and congestive heart failure. She had had chronic paranoid schizophrenia for 35 years and had been taking medications to control her psychiatric disorder for the past 10 years. A 2-dimensional echocardiogram performed at the onset of congestive heart failure showed dilated cardiomyopathy with global impairment of left ventricular function (ejection fraction <0.25). Despite withdrawal of the medications most likely responsible for the heart problems (perphenazine, 2 mg; and amitriptyline, 25 mg), the patient died of refractory congestive heart failure 2 years later. Histologic examination at autopsy showed evidence of persistent toxic myocarditis with fibrosis of the heart and persistent chronic hepatitis. These autopsy findings were considered to be drug related.