Cryoablation of AVNRT in children and adolescents: early intervention leads to a better outcome.

INTRODUCTION: Currently, transcatheter cryoablation is a well-established technique for the treatment of atrioventricular nodal reentry tachycardia (AVNRT) in children. In the past decade, many studies have focused on identifying factors that may affect acute and long-term outcome, but none has been shown to be strongly predictive of treatment success. The aim of our study was to determine whether patient age and cryoablation method correlate with acute and long-term success.

METHODS AND RESULTS: We retrospectively reviewed 202 consecutive patients (98 male, mean age 11.5 years; range: 4-20 years) who underwent cryoablation for AVNRT at our institution from October 2002 to August 2012. Patients were divided into 2 groups according to age: group A <12 years (n = 101) and group B ≥12 years (n = 101). A single lesion or linear lesion technique was employed. A total of 217 cryoablation procedures were performed: 106 (49%) in group A and 111 (51%) in group B. All patients were evaluated in our postoperative follow-up program. The overall recurrence rate was 10.9% (22/202). AVNRT recurrence was significantly lower in group A than in group B (4.95% vs 16.8%, P = 0.000). No significant differences in recurrence rate were observed between groups when using the single lesion versus linear lesion technique. There were no permanent cryoablation-related complications.

CONCLUSION: Our findings show that cryoablation had no complications and a very good success rate. Type of cryolesion is not predictive of long-term success, whereas lower recurrence rate is achieved when cryoablation is performed at a younger age.