Congenital Long QT Syndrome in an Infant

Long QT syndrome (LQTS) is a disorder of myocardial repolarization characterized by prolonged QT interval on ECG with prevalence close to 1/3000-1/5000. LQTS is characterized by the occurrence of syncopal episodes due to torsades de pointes ventricular tachycardia (VT) and by a high risk for sudden cardiac death among untreated patients (1, 2, 3). In 12% of patients with LQTS, sudden death is the first manifestation of the disease and only in 4% this happens in the first year of life (2). There is consensus that all symptomatic children with LQTS should be treated with β-blockers which are effective in preventing cardiac events and reducing mortality in 70%, but do not protect patients from sudden death completely (1,2,3,4). The prognosis is poor in untreated patients with annual mortality 20% and 10 year mortality up to 50% (1, 2). Here we present a case of relatively rare congenital heart rhythm disorders in an infant which required immediate treatment.