Ivabradine for Incessant Atrial Tachycardia in a 1-Year-Old Child After Tetralogy of Fallot Repair.

Background: Ivabradine is a novel drug with the ability to reduce heart rate without compromising myocardial contractility or blood pressure. Studies on this drug exist mainly for heart failure and coronary artery disease; for arrhythmia, the studies are limited to small sample trials and case series, mostly unrandomized. Additionally, its evidence for arrhythmia in pediatric patients is limited. Here, we present a case of successful ivabradine administration for incessant atrial tachycardia in a 1-year-old child following tetralogy of Fallot (TOF) repair. Case: A 1-year-old child experienced incessant tachyarrhythmia episodes after TOF repair. Multiple standard therapies, including adenosine, amiodarone, multiple cardioversions, beta-blockers, and digoxin, failed to convert the rhythm. Considering the limited therapy options and existing case reports, ivabradine was administered at a dose of 0.1 mg/kg. Subsequently, sinus rhythm was restored 8 h after its administration, with the heart rate significantly decreased, and the patient returned to a stable hemodynamic status. Discussion: Ivabradine may be an option for incessant atrial tachycardia in pediatric patients. Although most tachyarrhythmias following TOF repair occur due to a reentry mechanism, focal mechanisms can also occur, suggested by timing, gradual acceleration after cardioversion and its response to ivabradine. Future studies are needed to further understand the safety and efficacy of ivabradine for atrial tachycardia in pediatric patients.