Ten-year experience with the arterial switch operation.

BACKGROUND: Arterial level repair is considered the most appropriate procedure for transposition of the great arteries. This report describes our experience with the arterial switch operation over the past decade.

METHODS AND RESULTS: From January 1991 to January 2001, a total of 299 patients underwent an arterial switch operation for transposition of the great arteries or double-outlet right ventricle. Group I (n=169, 56.5%) comprised patients with transposition of the great arteries in whom the ventricular septum was essentially intact. Group II patients (n=130, 43.5%) had transposition of the great arteries with an additional significant ventricular septal defect or had double-outlet right ventricle with a subpulmonic ventricular septal defect. Of the total, 245 (82%) were males and 54 (18%) were females. In group I, the ages ranged from 2 days to 18 years (median 19 days) and weight ranged from 1.7 to 68 kg (median 2.5 kg). In group II, the ages ranged from 4 days to 4 years (median 90 days) and weight ranged from 2.5 to 17 kg (median 4 kg). Fifteen percent of the patients (25/169) in group I and 30% of the patients (39/130) in group II had features of bacteriologic infection. Arterial switch operation was performed on standard lines. In group I, 141 patients (83.4%) had a primary arterial switch operation while 28 (16.6%) underwent a rapid two-stage repair. Twenty-three patients required concomitant relief of associated anatomic left ventricular outflow tract obstruction. Operative mortality was 8.8% (15/169) in group I and 33% (44/130) in group II with an overall mortality of 19% (59/299). The major causes of operative mortality included pulmonary arterial hypertensive crisis (n=21), sepsis and related complications (n=16), and left ventricular failure (n=8). Coexisting arch anomalies, longer cross-clamp time, late presentation, and preoperative bacteriologic infections were incremental risk factors. Follow-up ranged from 1 to 10 years and was 87% complete. On follow-up, 91% of the patients were asymptomatic and off all medications. There were 3 late deaths and 5 patients required reoperation.

CONCLUSIONS: Excellent long-term results are obtained in operative survivors following the arterial switch operation. However. operative mortality remains a concern in our set-up.