ABSTRACT VENTRICULAR TACHYCARDIA is usually adequately controlled by various medications—procainamide hydrochloride and quinidine being the most effective. Recently external electric countershock has been recommended for patients failing to respond to drugs.1 This is a report of a man with a recent myocardial infarction who developed refractory ventricular tachycardia which was treated by external electric countershock.Report of a Case A 73-yr-old male had an acute posterior myocardial infarction in November, 1960. After an uncomplicated hospital course he was discharged on 5 mg of warfarin sodium daily. He remained well until May 25, 1962, at which time he suddenly developed dull, nonradiating lower anterior chest pain and upper abdominal pain of increasing severity. On May 28, 1962, because of pain and tachycardia, he was hospitalized. An electrocardiogram showed changes suggestive of ventricular tachycardia. The prothrombin content was 12% (38 sec with control of 14 sec); blood urea nitrogen was 21 mg%;