Management of Pediatric Supraventricular Arrhythmias

Background: Supraventricular tachycardia is the most common symptomatic arrhythmia in children.
Objective: To evaluate the incidence of supraventricular tachycardia in children, to identify the etiology and the predisposing factors and to propose an effective treatment strategy.
Method: Between January 2004 and December 2009, children with supraventricular arrhythmias treated in Pediatric Cardiology Clinic Tirgu-Mures, were included in this retrospective study. The arrhythmia was diagnosed with clinical examination, 12-leads ECG and/or 24 hours Holter monitoring, echocardiography for identification of associated cardiac malformations. In all cases the followed parameters were: age of onset, predisposing factors, underlying mechanism of arrhythmia, efficacy of treatment.
Results: 87 children with supraventricular arrhythmias with a median age of 9 years were included. Supraventricular tachycardias were the most frequent in children at school age and adolescents (70.1%); the incidence decreased in younger children and infants. Predisposing factors were cardiac malformations, cardiac surgery, dilatative cardiomyopathy, myocarditis. Trigger factors were physical exercises, infections, fever and emotions. The commonest underlying mechanism was atrioventricular nodal reentrant tachycardia (85.71%). The emergency treatment: vagal stimulation successful in 12 patients, medical treatment in 72 patients, electric cardioversion 3 patients. 90% of patients benefits of long-term treatment; the most used were betablockers and class III antiarrhythmics. Only 12% of patients present breakthrough episodes.
Conclusions: The incidence of supraventricular tachycardias in children is high, they are occurring frequently on structurally normal heart, but they have also many predisposing factors. The underlying mechanism is important in selection of effective medication. Class III antiarrhythmics were effective in cases refractory to other medications.