Atrioventricular nodal re-entrant tachycardia is an uncommon arrhythmia in children. The natural history of this disturbance is poorly known in young patients.

We analyzed the clinical and electrophysiological features, and the final outcome, in 19 children affected by typical atrioventricular nodal re-entrant tachycardia diagnosed by a transoesophageal electrophysiological study.

Of the cohort, 12 patients were female and 7 male, with a mean age of 11 years. Dual atrioventricular nodal physiology was demonstrated in 14 children (73%). The mean length of the tachycardia cycle was 297 milliseconds, with periods of 2 to 1 atrioventricular block during tachycardia noted in 5 children (26%). The mean cycle length was significantly shorter in the children who presented episodes of 2 to 1 atrioventricular block than in those who did not. After diagnosis, 12 children were not treated, 6 were treated with medical therapy, and 1 was submitted to radiofrequency transcatheter ablation. During a mean follow-up period of 41 months, 2 children with rare, but sustained, episodes of tachycardia that initially had not been treated were submitted to radiofrequency transcatheter ablation. Among children treated pharmacologically, 1 teenager was submitted to radiofrequency transcatheter ablation on the basis of parental choice, 3 children have discontinued medical therapy recording only sporadic episodes of tachycardia, and 2 children are still treated with antiarrhythmic drugs. At the last follow-up visit, 13 children (68%) were without any treatment, 4 had been successfully ablated, and 2 were still on medical treatment.

Our data indicates a relatively benign outcome in this group of children and adolescents with atrioventricular nodal re-entrant tachycardia.