Prenatal Echocardiographic Assessment of Foramen Ovale Appearance in Fetuses with D-Transposition of the Great Arteries and Impact on Neonatal Outcome

Introduction: Neonates with D-transposition of the great arteries (dTGA) may die at birth because of the inadequate intracardiac mixing due to a misdiagnosed restrictive foramen ovale. We reviewed our experience in echocardiographic assessment and perinatal management of fetuses with dTGA searching for new features that may predict the need for urgent balloon atrial septostomy (BAS) immediately after birth. Patients and Methods: We included fetuses diagnosed with dTGA between January 2000 and December 2014. We assessed pre- A nd postnatal appearance of the foramen ovale, ductus arteriosus and pulmonary veins. Both the diagnostic findings at the time of last prenatal echocardiogram and those findings deriving from a retrospective reevaluation of stored videos were considered. BAS was defined as urgent if performed in neonates with restrictive foramen ovale and severe hypoxemia. Results: We reviewed 40 fetuses with dTGA. 20/40 fetuses received urgent BAS at birth. Not only the restrictive but also the hypermobile and the redundant appearance of the foramen ovale was significantly associated with urgent BAS (p < 0.0001, p = 0.002 and p = 0.0001, respectively). Conclusions: Prenatal evaluation of the foramen ovale appearance in fetuses with dTGA is still challenging. Based on our experience, also the redundant foramen ovale appearance may need urgent BAS at birth