Multiple direct fetal amiodarone administration for supraventricular tachycardia with hydrops fetalis: a case report

BACKGROUND: Fetal supraventricular tachycardia (SVT) is the most common fetal tachyarrhythmia and can cause fetal heart failure and intrauterine death. The management varies within institution and usually based on published case series, institutional experience. CASE SUMMARY: Fetal SVT with hydrops (ascites and subcutaneous edema) was diagnosed at 26 weeks of gestational age. The first direct injection of fetal amiodarone into the umbilical vein resulted in temporary cardioversion to the sinus rhythm and mild transient maternal adverse event. The second direct fetal amiodarone to the fetal peritoneal cavity resulted in conversion to sinus rhythm, resolution of fetal hydrops, and normal fetal growth until delivery at 39 weeks gestational age. DISCUSSION: Treatment of fetal SVT often requires prolonged maternal antiarrhythmic treatment and carries a significant risk of maternal adverse events. Direct fetal antiarrhythmic treatment often requires achieving adequate therapeutic drugs, especially in hydropic fetus. Amiodarone is one of drugs options for fetal SVT with hydrops because it has been shown to be highly effective with low fetal mortality. Continuous vital sign and ECG monitoring should be performed during direct fetal antiarrhythmic administration.