Persistence of eustachian valve-rare cause of intra cardiac shunting leading to neonatal cyanosis

Eustachian valve (EV) is an embryological remnant of the inferior vena cava (IVC) which helps in diverting oxygenated blood from IVC towards foramen ovale during fetal life. It usually regresses after birth however its persistence can lead to complications in the neonatal period. In this case report, we present a newborn with persistence of EV presenting with central cyanosis. Echo cardio graphic examination revealed right-to-left atrial level shunting through patent foramen ovale due to prominent/persistence of EV. The patient was managed conservatively and discharged in stable condition with regular cardiology follow up in clinic