BACKGROUND The need for cardiopulmonary bypass in the treatment of penetrating heart injuries is debated. OBJECTIVES To review our experience with penetrating heart injuries and determine the indications and outcome for cardiopulmonary bypass. DESIGN Retrospective review. SETTING A university-based, level I trauma center. PATIENTS All victims of penetrating heart injury presenting between July 1, 1989, and December 31, 1995. METHODS Medical records were reviewed for demographic and physiological data, operative findings, and outcome. RESULTS Overall survival for 106 patients with penetrating heart injury was 55%. In an effort to resuscitate the heart, 4 patients with unresponsive cardiogenic shock were placed on cardiopulmonary bypass; none survived. Of 30 patients with multiple-chamber injuries, 11 presented with signs of life and 7 survived. Cardiopulmonary bypass was essential to repair complex injuries in 2 of the 7 survivors. CONCLUSION Cardiopulmonary bypass was ineffective in salvaging patients with cardiogenic shock but was essential in some patients with complex multiple-chamber cardiac injuries that could not be exposed and repaired by other means.