In a 52-year-old man with severe chest pain of 3 hours duration and ST-segment elevation in leads V1 and V2, a nondominant right coronary artery was recanalized by an intracoronary infusion of urokinase. Coronary cineangiography revealed a total occlusion of the nondominant right coronary artery and no significant narrowing of the left coronary artery. Hemodynamic studies during the acute phase of myocardial infarction demonstrated an increase of right atrial mean pressure in association with normal pulmonary capillary wedge pressure. Following the recanalization, chest pain disappeared and hemodynamic alterations were corrected. The purpose of this report is to document a case of isolated right ventricular infarction due to a nondominant right coronary artery occlusion.