Our purpose was to evaluate the impact of coronary pattern on survival and reintervention in patients who underwent the arterial switch operation with a single coronary artery.We conducted a retrospective analysis of 53 patients with a single coronary artery who underwent the arterial switch operation between 1983 and 2000 at Children's Hospital Boston. Recent follow-up information was obtained for 40 of the 46 long-term survivors (mean follow-up 7.3 +/- 4.5 years).Thirty-five patients had a single right coronary artery, with the left coronary artery posterior to the pulmonary artery in 27. Eighteen patients had a single left coronary artery (16 with the right coronary artery anterior to the aorta). Six of 7 total patients who died had a single right coronary artery; all died before 1992. There were 5 early deaths, all with a single right coronary artery, with 4 deaths due to coronary malperfusion. Survivals for all patients were 91% at 6 months and 87% at 1, 5, and 10 years after the arterial switch operation. Survival figures were lower for patients having a single right ostium with the left main coronary artery posterior to the pulmonary artery compared with all other subtypes (P =.02, log-rank test). Seven patients had reintervention, 4 because of right ventricular outflow tract obstruction, 1 for heart transplantation, 1 for mitral valve repair and 1 for pacemaker implantation. Freedom from reintervention for all patients was 96% at 6 months, 92% at 1 year, 86% at 5 years, and 82% at 10 years after the arterial switch operation, with lower rates for patients having a single left ostium with the right coronary artery anterior to the aorta (P =.0003, log-rank test).In the current era, the arterial switch operation with a single coronary artery can be performed safely irrespective of the coronary anatomy. Risk of reintervention is higher in patients having a single left ostium with the right coronary artery anterior to the aorta.