Intracardiac Adenosine Triphosphate for Cardioversion of Supraventricular Tachycardia in a Hydropic Fetus: a case report

Abstract Background Fetal supraventricular tachycardia (SVT) can cause fetal hydrops and demise if untreated. Transplacental therapy often fails in severe SVT with fetal hydrops due to impaired placental drug transfer. In the present study, we report the first successful cardioversion of recalcitrant SVT in a hydropic fetus by intracardiac adenosine triphosphate (ATP) administration. Case Summary A 34-year-old woman at 28+6 weeks of gestation was admitted for persistent fetal tachycardia, subsequently diagnosed as fetal SVT. After combined transplacental therapy with digoxin and sotalol, the fetal tachycardia remained uncontrolled, with progressive hydrops and deteriorating cardiac function. Ultimately, intracardiac ATP administration was performed and achieved successful cardioversion of the fetal SVT. No procedure-related complications occurred. After the procedure, maternal oral digoxin and sotalol were continued to maintain fetal sinus rhythm. Discussion Intracardiac ATP administration offers a last-resort salvage therapy for terminating recalcitrant SVT with fetal hydrops, which should be reserved for highly selected patients and performed at specialized centers. The larger studies with longer follow-up are needed to validate this procedure’s efficacy and safety.