Combination Therapies of Amiodarone and Digoxin for Refractory Supraventricular Tachycardia Accompanied by Congenital Heart Diseases in a Preterm Infant with Hydrops Fetalis

Fetal tachycardia is at risk for developing low cardiac output, non-immune hydrops fetalis and ultimately fetal death. Spontaneous resolution of supraventricular tachycardia (SVT) is common during the first year of age, but some infants need long-term antiarrhythmic therapy. In almost neonatal tachyarrhythmia including SVT, adenosine is the drug of the first choice. Digoxin is used to treat the SVT which is not controlled with adenosine. Class Ic and III antiarrhythmic drugs are additionally recommended for the disease unresponsive to digoxin. Intravenous amiodarone is highly effective and safe in an infant with refractory or life threatening tachycardia. Some cases have been reported that amiodarone combined with digoxin therapy is effective for treating tachycardia. We herein report a case of a preterm infant-born at 32 weeks of gestational age-with hydrops fetalis and life-threatening refractory SVT accompanied by multiple congenital heart diseases. SVT was initially not responsive to adenosine therapy, however, it was then successfully controlled with combination therapies of amiodarone and digoxin.