Comparison of Transplacental Treatment of Fetal Supraventricular Tachyarrhythmias With Digoxin, Flecainide, and Sotalol

Abstract

Background-Fetal tachyarrhythmia may result in low cardiac output and death. Consequently, antiarrhythmic treatment is offered in most affected pregnancies. We compared 3 drugs commonly used to control supraventricular tachycardia (SVT) and atrial flutter (AF). Methods and Results-We reviewed 159 consecutive referrals with fetal SVT (nϭ114) and AF (nϭ45). Of these, 75 fetuses with SVT and 36 with AF were treated nonrandomly with transplacental flecainide (nϭ35), sotalol (nϭ52), or digoxin (nϭ24) as a first-line agent. Prenatal treatment failure was associated with an incessant versus intermittent arrhythmia pattern (nϭ85; hazard ratio [HR]ϭ3.1; PϽ0.001) and, for SVT, with fetal hydrops (nϭ28; HRϭ1.8; Pϭ0.04). Atrial flutter had a lower rate of conversion to sinus rhythm before delivery than SVT (HRϭ2.0; Pϭ0.005).Cardioversion at 5 and 10 days occurred in 50% and 63% of treated SVT cases, respectively, but in only 25% and 41% of treated AF cases. Sotalol was associated with higher rates of prenatal AF termination than digoxin (HRϭ5.4; Pϭ0.05) or flecainide (HRϭ7.4; Pϭ0.03). If incessant AF/SVT persisted to day 5 (nϭ45), median ventricular rates declined more with flecainide (Ϫ22%) and digoxin (Ϫ13%) than with sotalol (Ϫ5%; PϽ0.001). Flecainide (HRϭ2.1; Pϭ0.02) and digoxin (HRϭ2.9; Pϭ0.01) were also associated with a higher rate of conversion of fetal SVT to a normal rhythm over time. No serious drug-related adverse events were observed, but arrhythmia-related mortality was 5%. Conclusion-Flecainide and digoxin were superior to sotalol in converting SVT to a normal rhythm and in slowing both AF and SVT to better-tolerated ventricular rates and therefore might be considered first to treat significant fetal tachyarrhythmia. (Circulation. 2011;124:1747-1754.)

First‐Line Antiarrhythmic Transplacental Treatment for Fetal Tachyarrhythmia: A Systematic Review and Meta‐Analysis

“…A, Flecainide vs digoxin in termination of supraventricular tachycardia 4, 6, 8, 9, 21, 24, 26. B, Digoxin vs sotalol in termination of supraventricular tachycardia 8, 9, 24.…”

“…Sotalol vs digoxin in the termination of atrial flutter 9, 24. CI indicates confidence interval; RR, relative risk.…”

“…The side effects of the flecainide were nausea, dizziness, visual disturbances, heightened alertness, Brugada pattern on ECG, and headache, whereas the side effects of digoxin were nausea, dizziness, visual disturbances, and first‐degree atrioventricular block 4, 21. The side effects of sotalol were nausea, dizziness, and bradycardia 9. The majority of the maternal side effects were minor and did not require drug changes.…”

“…A, Maternal side effects during treatment with digoxin vs flecainide 4, 9, 21. B, Maternal side effects during treatment with digoxin vs sotalol 9, 24.…”

“…Digoxin, sotalol, flecainide, amiodarone, and other antiarrhythmic agents have been described as successful interventions to treat fetal SVT and AF in multiple studies. These studies were mostly single‐center studies, and had small sample sizes 8, 9, 10, 11. Secondary to this gap in the literature, recent statements from the American Heart Association acknowledged the lack of consensus on the most effective and best tolerated first‐line agent for fetal SVT or AF 12…”