Sixty-four consecutive patients with penetrating cardiac injuries were treated between January, 1977, and January, 1983, at the University of Maryland Hospital. Twenty-eight patients had major associated injuries of other organs. The patients were divided into groups according to their clinical status on arrival. An aggressive approach was utilized including early emergency room (ER) thoracotomy for "lifeless" or deteriorating patients. Three patients required immediate cardiopulmonary bypass for repair of their injuries. Twenty-one (57%) of the 37 patients undergoing ER thoracotomy survived; most of the deaths occurred in patients arriving "lifeless" from gunshot wounds. Twenty-four (89%) of the 27 patients who were in stable enough condition to undergo initial repair in the operating room (OR) survived. Overall survival was 45 patients (70%). Though superficial wound infections developed in 18 patients, there were no deep or systemic infections. None of the survivors sustained severe neurological sequelae. Five patients underwent late reoperations for closure of a ventricular septal defect (2), mitral valve replacement (1), and pericardiectomy (2) with no deaths. Though repair of penetrating cardiac injuries should preferably be carried out in the OR, immediate thoracotomy for "lifeless" or deteriorating patients can be performed in the ER with a low incidence of direct surgical complications and with high patient survival.