Transplacental Flecainide Therapy for Fetal Supraventricular Tachycardia in a Twin Pregnancy

Abstract

We present the case of a twin pregnancy in which 1 fetus developed hydrops secondary to supraventricular tachycardia at 30 weeks' gestation. Transplacental flecainide administration successfully treated the condition without evidence of maternal or fetal side-effects. The case raises ethical and possibly legal issues that present when 1 fetus in a twin pregnancy develops a condition the management of which could cause complications to the other twin and/or the mother.

Fetal arrhythmias: Natural history and management

“…These series achieved therapeutic serum levels in 91.5% of cases and a success rate of 59% to 95% (Simpson and Sharland 1998;Krapp et al 2002). Because of the maternal and fetal side effects (Kleiman et al 1999;Edwards et al 1999), including neurologic impairment thought to be due to dysregulation of cerebral perfusion secondary to sudden modification of the fetal heart rate (Krapp et al 2002), flecainide is indicated only in the presence of hydrops. In our series, treatment with digoxin was successful in all four cases of SVT with cardiac failure and normal cardiac anatomy.…”

Transplacental flecainide therapy in the treatment of fetal supraventricular tachycardia

“…Fetal arrhythmias can complicate approximately 2% of all pregnancies during the third trimester (Edwards et al, 1999). The most significant consequence of fetal tachyarrhythmias is the development of non-immune hydrops and its associated perinatal mortality of 50-98% (Allan et al, 1991;Owen and Cameron, 1997).…”

“…This trial studied the risk of serious arrhythmias developing in patients treated with flecanide (and ecainide) for resolution of ventricular ectopics following a myocardial infarction. It was discontinued before its completion due to the increased mortality rates in patients treated with these drugs; however, it must be recognised that this trial is not directly applicable to the use of flecanide in healthy pregnant women and no significant maternal adverse effects have been reported (Edwards et al, 1999).…”

“…Resolution has been shown to occur in over 85 per cent of fetuses when flecainide is used (Edwards et al, 1999). The main concerns in its use, however, are its recognised side effects and as a result, digoxin still remains a valid choice in the fetuses with no hydropic changes.…”

Diagnosis, Treatment, Observation and Outcome of Fetal Supraventricular Tachycardia in a Twin Pregnancy

“…At a critical heart rate of more than 210 bpm the risk of cardiac failure, nonimmune hydrops, and eventual intrauterine death increases [2] . Although prenatal anti-arrhythmic treatment is now well established, few published reports describe this condition in the setting of multiple pregnancies [3] . There is still discussion about the best treatment option for SVTs.…”