RADIOFREQUENCY ABLATION FOR SUPRAVENTRICU LAR TACHYCARDIA IN PEDIATRICS

Supraventricular tachycardias (SVT) are the most frequent cause of tac hycardia in children. Its pharmacological treatment has adverse effect s, is not curative, and is not always effective. During the last few y ears radiofrequency ablation (RF-A) has changed the treatment. The pur pose of this study is to evaluate our experience in RF-A in children w ith SVT. Between 1990 and 1995, 92 patients (1 month to 17 years old) underwent electrophysiological study after the diagnosis of SVT. RF-A was attempted in 55 patients with accessory pathways (AP), slow-pathwa y of the atrioventricular node, or ectopic focus. The site of ablation was decided according to the electrical signals and the catheter posi tion. The success of the RF-A was confirmed by the interruption of the tachycardia, the change in the sequence of activation of the intracar diac signals, the regression of the preexcitation, and the inability t o reinduce tachycardia. RF-A was successful in 81% of the patients; 88 % in those with a left AP, 56% in those with a right AP, and 100% in t hose with nodal reentry. Complications were seen in 7% of the patients : 3 with arterial obstruction, one with a minimal pneumothorax, and on e with cardiac tamponade. During a follow up of 16.6 months there was no relapse nor late complications. We conclude that RF-A is a safe and effective procedure in pediatric patients with SVT.