Idiopathic severe constriction of the fetal ductus arteriosus: a possible underestimated pathophysiology

Idiopathic intrauterine constriction/closure of the ductus arteriosus, which is distinct from that secondary to maternal exposure to non-steroidal anti-inflammatory drugs, such as indomethacin, or structural cardiac defect, is an uncommon event that often results in severe fetal-neonatal morbidity and mortality. We reported a case of idiopathic fetal ductal constriction, in which the diagnosis was confirmed by documentation of an abnormal four-chamber view of the fetal heart at 38 weeks of gestation on obstetric ultrasound examination. A female infant weighing 2,816 g was born by Cesarean section, and her postnatal course was mild; transient tachypnea requiring only several days of supplemental oxygen with spontaneous regression of the abnormal echocardiographic findings by 3 months of age. The incidence of idiopathic constriction/closure of the fetal ductus arteriosus may be underestimated, particularly with a negative history of maternal drug exposure and mild postnatal clinical presentation.