25 years after the first arterial switch procedure: mid-term results.

BACKGROUND: 25 years after the first successful arterial switch operation (ASO) for complete transposition of the great arteries (TGA), it is possible to evaluate the mid-term results after this procedure. PATIENTS AND METHODS: From March 1986 through December 1993, 188 patients with TGA underwent ASO (primary in 181 patients and secondary after previous banding of the pulmonary artery in 7 patients). Of the 181 patients with primary ASO, 152 had simple TGA or TGA with a small ventricular septal defect, 90 patients had TGA with a large ventricular septal defect, and 10 had a Taussig-Bing complex. Unselected subgroups of the patients were specifically examined with respect to general health, cognitive and motor development, exercise tolerance and cardiological status. Follow-up time was over 5 years except for the cardiac catheterizations, which were performed one year after ASO.
RESULTS: Early mortality was 6.4% in the total group and 5.5% in the 181 patients with primary ASO. 5 patients (2.7%) died late and 5 patients needed reoperation during the follow-up period. Cumulative survival for the whole group was 91% at 5 and 10 years after ASO. 96% of the patients were unlimited in their physical activity, and 99% received no medication. Intelligence was not different from a normal population, but motor and neurological impairment was more frequent (23% and 9%, respectively). The Bruce treadmill test was normal in 47 of 50 patients, but provoked signs of myocardial ischemia or salvos of ventricular tachycardia in 3. ECG and Holter ECG showed normal sinus rhythm in 94.5%, important ventricular ectopy in 2.8% and ischemic changes in 1.4%. Right heart catheterization in 67 patients revealed flattening of the pulmonary trunk and frequently mild or rarely moderate pulmonary artery branch stenosis. Left heart catheterization in 71 patients demonstrated significant enlargement of the aortic annulus and root as well as frequent mild aortic insufficiency. One child had unexpected coronary artery occlusion,and 2 showed a hypoplastic left anterior descending coronary artery. In all patients except one, left ventricular ejection fraction was normal, but 6 patients had regional wall motion abnormalities.
CONCLUSION: These results and those of other groups are encouraging, but prospective studies over a much longer follow-up time are necessary before definite conclusions can be drawn.