Fetal arrhythmias: Ten years’ experience and review of the literature

Objective: Fetal arrhythmias complicate 1-2% of all pregnancies. Ultrasound evaluation and Doppler technology are indispensable in both diagnosis and management. Digoxin, sotalol, flecainide and amiodarone are widely accepted antiarrhythmic agents that are frequently. We reviewed the maternal and fetal outcomes in cases with fetal arrhythmia in a tertiary care center in the last decade. Materials and Methods: Fetal arrhythmias were classified under three main groups: Irregular rhythms, tachyarrhythmia and bradyarrhythmia. Detailed anatomical evaluation and fetal echocardiography were performed in all cases to determine whether a structural cardiac and extracardiac anomaly accompanied fetal arrhythmia and the type of fetal arrhythmia. Digoxin was started primarily as first-line therapy in patients with persistent fetal tachyarrhythmia. In cases, not responding to digoxin, other antiarrhythmic agents (sotalol, flecainide) were combined with treatment without discontinuing digoxin. Results: Fetal arrhythmia was detected in 36 cases during the study period. 50% (n=18/36) of the cases had supraventricular tachycardia, whereas 28% (n=10/36) of them were fetal bradyarrhythmia and 22% (n=8/36) of them were with various irregular rhythms. Transplacental therapy was initiated in 13 patients with persistent supraventricular tachycardia and atrial flutter regardless of the presence of hydrops. The success rate in transplacental therapy was 77% (n=10/13). Conclusion: Successful transplacental therapy was achieved in approximately 80% of cases and delivery could be postponed to advanced gestational weeks, confirming the crucial role of this treatment for the management of tachyarrhythmia.