Transposition of the great vessels (TGV) occurs in approximately 20% of children who die with congenital heart disease.1With rare exceptions, patients with this lesion die in the first 6 months of life (50% within the first month). Approximately 40% of patients with TGV have an otherwise normal heart. In recent years, various types of complete corrections for this lesion have been attempted. Mustard et al2has simplified these procedures and has reduced mortality to reasonable levels. Best results are obtained in children well beyond 6 months of age. Therefore, it is imperative to provide early palliation that is effective until the optimal age for complete correction and that does not interfere significantly with subsequent surgery. Creation of an interatrial communication seems the best available choice to suit these requirements. The Blalock-Hanlon technique,3or some modified version, is commonly used to remove a portion of the atrial