Prenatal closure of the foramen ovale in complete transposition of great vessels. Observations in a case with intact ventricular septum and normally developed left heart chambers.

A rare case is reported of premature closure of the foramen ovale in d-transposition of the great vessels with intact ventricular septum and normal development of the left side of the heart. Asphyxia neoatorum and cardiac failure were the manifestations in the early neonatal period. Balloon atrial septostomy during cardiac catheterization would be unsuccessful in infants with this condition, and closed atrial septectomy (Blalock-Hanlon procedure) would be necessary for survival.