Sotalol prophylaxis was efficient and safe for supraventricular tachycardia in early infancy.

Abstract

There is no consensus on the best prophylaxis for supraventricular tachycardia (SVT) in infancy. We studied the efficacy and safety of sotalol. This retrospective study comprised infants diagnosed with SVT before 1 year of age and treated with sotalol during 2002-2018 in Stockholm, Sweden. The patients' characteristics, comorbidities, sotalol dosages, QT intervals and outcomes were extracted from their medical records. We studied 85 infants (65% boys) with a median age of eight (range 0-288) days at the time of diagnosis, including 78 with re-entry tachycardia. Sotalol was completely or partially successful in the 67/75 patients who completed the treatment, as well as in four of the seven patients with other tachycardia mechanisms. The 48 infants with postnatal debut had significantly higher success rates than the 27 with foetal debut (96% vs. 78%, p = 0.04). Prolongation of corrected QT (QTc) intervals of ≥450 ms occurred in 16% of the total cohort and two patients with QTc intervals of ≥500 ms had their treatment changed. There were no cases of proarrhythmia after sotalol treatment. Sotalol provided effective and safe prophylaxis for SVT during infancy. QTc prolongation rarely caused treatment discontinuation and there were no cases of proarrhythmia.