Interim results after arterial switch operation in transposition of the great arteries

Question: The arterial switch operation is the procedure of choice for the neonatal anatomical repair of a simple transposition of the great arteries. Whereas short term prognosis is good, long-term prognosis is uncertain. Method: Between 1986 und 1993 165 children with a mean age of 9+/-7 days underwent arterial switch operation for transposition of the great arteries (closure of a ventricular septal defect simultaneously performed in 15 patients). To obtain more detailed insight into the prognosis of children after the arterial switch operation, we analyzed the clinical outcome of our patients (mean follow-up period 43+/-24 months), especially considering the prognosis of postoperative complications. Results: Early mortality was 5.5% (9 patients),and there were 3 late deaths. During follow-up electrocardiographic signs of myocardial infarction persisted in 4 patients. Significant supravalvular pulmonary stenosis was noted in 18 children (pressure gradient 30-50 mmHg: n=14; >50 mmHg: n=4). Twelve patients had a second operation:9 for aortic coarctation, 2 for supra-and subvalvular pulmonary stenosis respectively, and 1 for occlusion of the left coronary artery. Neuromotor function is normal in 131 children while 22 children are suspected to have a developmental delay. Post-hemorrhagic hydrocephalus requiring a ventriculoperitoneal shunt occured in 2 patients. After two yea rs of life on ly 1 patient is medicated (for exercise-induced ventricular arrhythmia). Conclusion: Interim results after the arterial switch operation for transposition of the great arteries are encouraging. Further observations should clarify the long term prognosis of affected children.