[Arterial switch operation: late results and a future perspective]

Intermediate results of the arterial switch operation for variety of cardiac anomaly with the transposed great arteries were studied to elucidate late results and problems. Seventy-five survivors of the arterial switch operation at our institute between 1991 and January 2007 were studied retrospectively. Mean follow-up time was 7.5 years. There were 2 late deaths, 3 reoperations, and 9 cases of catheter intervention, resulting in actuarial survival of 97%, and event-free rate of 83% at 16 years. Seventy patients (93%) were medication free and had no restriction on physical activities. Moderate pulmonary stenosis in 2 patients and mild pulmonary stenosis in 14 were observed. Moderate aortic regurgitation in 2 and mild aortic regurgitation in 20 were observed. Risk factors for right ventricular outflow obstruction were a diagnosis of double outlet right ventricle (DORV), association with aortic arch obstruction, and prior pulmonary artery banding (PAB). Risk factors for branch pulmonary artery stenosis (PS) were not clear; however, scar formation with use of xenograft patch and in-fold formation by redundant autologous pericardial patch for closure of the defects in the old aortic root seemed to be related with the stenosis. Risk factors for aortic regurgitation were age at operation and prior PAB. Early primary arterial switch operation may resolve these problems.