Prenatal Diagnosis of Ventricular Tachycardia Initiated from Bradycardia

Fetal ventricular tachycardia (VT) is an extremely rare condition. Because sustained VT is highly associated with perinatal morbidity and mortality, prenatal management with antiarrhythmic drugs is crucial. A 33-year-old woman was referred to our hospital for fetal bradycardia at 25.2 weeks of gestation. Initial echocardiography showed bradycardia with irregular atrial beats, which was suspected as blocked atrial bigeminy. Four weeks later, the fetal tachycardia was accompanied by no atrioventricular conduction. Therefore, VT was diagnosed. The fetus developed hydrops. Despite the use of antiarrhythmic drug, the neonate died a few hours after birth because of persistent VT. Only few cases of fetal VT have been reported worldwide, and no case has been reported in Korea. Here, we report a case of fetal VT and discuss the prenatal management using antiarrhythmic drugs, reviewing previous reports.