ARTERIAL SWITCH OPERATION FOR SIMPLE AND COMPLEX TGA-INDICATION CRITERIA AND LIMITATIONS RELEVANT TO SURGERY

Since 1983, 505 patients underwent the arterial switch operation (ASO). 326 (28 days) had transposition of the great arteries with an intact ventricular septum (TGA/IVS) and 179 had a ventricular septal defect (TGA/VSD). Mean age at ASO was 7 +/- 5 days. Total mortality in the neonatal group was 7%. In the last 150 neonates, there was no operative mortality. Two late deaths were due to coronary obstruction 6 and 7 weeks after ASO. Cardiac catherisation in 106 late survivors revealed a mean gradient form RV to PA of 20 +/- 20 mmHg, and from LV to aorta of 5 +/- 8 mmHg. Mean PA pressure was 13 +/- 4 mmHg; enddiastolic pressure in the left ventricle was 8 +/- 3 mmHg. Cardiac index was 4.0 +/- 1.2 L/min. Sinus node recovery time was normal in 97%. Asymptomatic occlusion of a coronary artery was present in 3 patients. Aortic regurgitation was moderate in 1%. Rapid two-stage ASO (preliminary PA banding and shunt followed by ASO after 7 days) was carried out successfully in 29/30 patients with TGA/IVS, the oldest being 28 months of age. The ASO, as a primary operation, is our treatment of choice for neonates with TGA/IVS and TGA/VSD. The rapid two-stage approach is applicable for older patients with TGA/IVS.