Rapid control of foetal supraventricular tachycardia with digoxin and flecainide combination treatment.

OBJECTIVES: To evaluate the efficacy of flecainide and digoxin combination in foetal supraventricular tachycardia.

SETTING: This study was carried out in a tertiary referral centre.

METHODS: We conducted a retrospective review of 29 patients diagnosed with supraventricular foetal tachycardia between 2001 and 2009. Mode of presentation, foetal cardiac function, maternal anti-arrhythmic serum levels, drug tolerance, and maternal electrocardiogram recordings were assessed. The postnatal outcome of each infant was also evaluated for tachycardia recurrence.

RESULTS: In all, 27 foetuses were treated with digoxin and flecainide combination, and two foetuses were delivered without any treatment. Of the 27 foetuses treated, six [corrected] had atrial flutter and the remaining 21 [corrected] had atrioventricular re-entry tachycardia. There were eight foetuses with hydrops (27%), of whom three had atrial flutter and five had atrioventricular re-entry tachycardia; 26 foetuses (96%) responded to flecainide and digoxin combination, with restoration of sinus rhythm in 22 (81.4%) and rate control in the other four. In one severely hydropic foetus, there was no response to treatment. In all, 26 treated infants were delivered alive, but one pregnancy was terminated for non-cardiac causes when the foetus was in sinus rhythm. There was no intrauterine death due to tachycardia. Although there were minor side effects to anti-arrhythmic medications, none of the pregnant women developed proarrhythmia.

CONCLUSION: Flecainide and digoxin combination treatment offers a safe and effective treatment for foetal supraventricular tachycardia with fast restoration of sinus rhythm.