Forewarned is forearmed: The critical role of prenatal diagnosis in managing high-risk neonates with transposition of great arteries-intact ventricular septum

Most neonates with prenatally detected d-transposition of great arteries with intact ventricular septum (TGA-IVS) have a relatively standard preoperative course, but some patients with restrictive foramen ovale (FO) or ductus arteriosus tend to have severe hypoxemia after birth, posing a significant risk of mortality in the first few hours after birth. Poor mixing of oxygenated and deoxygenated blood leads to severe cyanosis and death. We present two prenatally diagnosed neonates with TGA-IVS who presented with significant desaturation, necessitating emergency balloon atrial septostomy (BAS). In both patients, the resultant mixing was inadequate; ductal stenting had to be resorted to restore oxygenation. These cases highlight the importance of prenatal identification of high-risk features, such as restrictive FO or ductal constriction, in fetuses with TGA-IVS. A small proportion of these babies who have inadequate mixing despite an anatomically adequate BAS can be further stabilized before surgery by means of ductal stenting.