Fetal supraventricular tachycardias: diagnosis and management.

In the majority of cases, the diagnosis of an isolated fetal tachyarrhythmia results in a favorable perinatal outcome. Although there is general consensus on the management of fetal extrasystoles, refractory supraventricular tachycardia, and atrial flutter and fibrillation, the optimal approach to supraventricular tachycardia without hemodynamic compromise remains uncertain. The benefits of conservative management without antiarrhythmic therapy must be weighed carefully against the lack of reliable predictors for the development of fetal hydrops and associated neurologic complications.