OBJECTIVE The presence of single coronary artery (CA) in the arterial switch operation (ASO) for neonatal treatment with transposition of the great arteries (TGA) has been reported to be an independent risk factor for early death after surgical repair and late reintervention. The study objective was to evaluate the mortality and the CA stenosis risk at early and long term in neonatal ASO for TGA and single CA. METHODS Between January 1987 and January 2010, 979 neonates underwent an ASO, of which 73 had a single CA (7.5% of all cohort): right ostium with posterior left CA loop was the most frequent pattern (63%), followed by left ostium with an anterior right CA loop (26%). Mean age at operation was 9.3 ± 5.7 days. Mean follow-up was 9.8 years (range: 1-20 years). RESULTS Eight patients (11%) died, 6 of coronary-related death. Overall, survival was 90.1 ± 1.9% at 1 year and 88.6% ± 3.8% at 2, 5, 10 and 15 years, respectively. Independent risk factor for mortality was associated surgery before 2001. Freedom from coronary events was 91.6 ± 3.3% at 1 year and 88.7 ± 3.8% at 5, 10 and 15 years respectively. No patients required late reintervention for CA surgery or angioplasty. CONCLUSIONS All coronary-related death occurred within the first 6 months after ASO, and all patients but 1 were operated before 2001. In our experience, it appears that a single CA is not any more a risk factor for early and late mortality after ASO for TGA. Mortality has drastically reduced since 2001 and is now close to that found in TGA with standard coronary patterns. The acquired experience shared between the surgeons and the institution offsets the undeniable surgical difficulty.