[What is necessary for improvement of arterial switch operation?]

We report long-term results of the arterial switch operation (ASO) and postoperative complications related to operative procedure. Between 1998 and 2007, ASO were performed in 42 patients [transposition of the great arteries (TGA) with intact ventricular septum:21, TGA with ventricular septal defect (VSD):13, Taussig-Bing anomary (TBA):7, and double outlet right ventricle with noncommitted VSD:1]. Hospital death occurred in 1 patient (2.4% mortality rate) due to low cardiac output syndrome (LOS) caused by prolonged aortic clamp, who had TGA with VSD, coactation of aortic arch and right ventricular outflow obstruction. Four patients required re-operation (freedom from re-operation rate was 84.7%). Two had pulmonary stenosis and 1 needed right ventricular outflow tract (RVOT) reconstruction with transannular patch. His pulmonary valve used for previous VSD closure was diminished. The other required muscle resection of RVOT. Five patients presented grade II or more neo-aortic insufficiency and 2 of them were TBA. Both these TBA, rerouting of left ventricular outflow tract (LVOT) to the aorta was challenging, they showed LVOT obstruction postoperatively. One underwent aortic valve plasty and the other had residual VSD closure. None had coronary event or abnormality in coronary arteriography. Selection of surgical procedure should be based on morphologic features in order to improve surgical outcome.