Introduction and Objectives. The immediate postoperative period is a critical phase in heart transplantation. Severe complications occur that may influence short-term and medium-term morbidity and mortality in these patients. The aim of this study was to analyze the incidence of severe complications in emergency and nonemergency transplantations. Materials and Methods. We studied 152 patients who underwent heart transplantation between 2001 and 2007. Combined transplantations and retransplantations were excluded. Two groups were considered: emergency transplantations (36 patients, 24%) and elective transplantations. We compared survival and occurrence of infection, primary graft failure (PGF), renal and hepatic failure, respiratory complications, cardiac tamponade, arrhythmias, reoperation, and intensive care unit (ICU) stay. Results. The emergency transplantation group had a greater number of ischemic patients, with a more prolonged cardiopulmonary bypass time, and a larger proportion of donors were women. Overall mortality in the intensive care unit was 2.6%, with no differences between groups. However, emergency procedures were significantly associated with a higher incidence of PGF, need for intraaortic balloon pump, and a more prolonged mechanical ventilation time, as well as a greater number of bacterial infections and a significantly longer ICU stay. Conclusions. In our series, emergency transplantation showed no greater perioperative mortality. We observed a greater number of severe complications, such as PGF, bacterial infection, and more prolonged mechanical ventilation time.