Objective: The aim of this study was to assess the short- and long-term outcomes of patients who underwent the arterial switch operation (ASO) at Siriraj Hospital in Thailand, and to identify postoperative complications and factors that significantly affect patient survival.

Methods: We retrospectively studied all patients with dextro-transposition of the great arteries and anatomic variants who underwent the ASO from January 1995 to December 2020. Twenty-year overall survival and 15-year freedom from reoperation/reintervention were estimated using the Kaplan-Meier method. Univariate and multivariate Cox regression analyses were used to identify factors independently associated with 30-day mortality.

Results: Of the 171 patients included, there were 116 males (67.84%). The median (minimum, maximum) age at operation was 33.5 (3-4,499) days, and the median (minimum, maximum) bodyweight was 3.4 (2.2-44.9) kg. Most patients (115/171, 67.25%) had an intact ventricular septum, whereas 48/171 (28.07%), had ventricular septal defects. The typical coronary anatomic pattern (1LCx-2R) was found in 120 patients (70.1%). Early mortality was 8.7% ± 4.4%, and there was no late death up to 20 years postoperatively with a median follow-up of five years. Fifteen-year freedom from reoperation or reintervention was 85.7%. Atypical coronary pattern was an independent factor for survival with an adjusted hazard ratio of 5.1 (95% confidence interval: 1.22-21.4; P = .026).

Conclusions: The results of this study revealed excellent short- and long-term outcomes of the ASO at our center. Atypical coronary anatomy was found to be the only factor that independently predicted 30-day mortality.