272 Efficacy of cryocatheter ablation as alternative treatment for atrioventricular reentrant tachycardia: A randomized study

Abstract

Radiofrequency ablation (RF) of atrioventricular reentrant tachycardia (AVNRT) is an effective method for treating this arrhythmia. However, inadverted AV block requiring implantation of permanent pacemaker is a worrisome side effect Although permanent AV block seems to be rare nowadays, patients are by no means spared from this severe complication. Catheter cryoablation is emerging as an alternative technology with an excellent safety profile, but limited data exist regarding its efficacy. We conducted a randomized study among patients with AVNRT remited to our center for EP study and ablation between January 2008-June 2010. After given written consent, patients were randomized to conventional RF or cryoablation, unless specific preference of patients was stated. The primary outcomes were acute success, SVT recurrence and complications, including AV block. 119 patients were included in our study (60 cryoablation group, 59 conventional RF). There were no differences in demographic and clinical baseline data between groups, including mean age. Acute procedural success was achieve in 59 patients (98%) of cryoablation group, and 59 (100%) of RF. One patient in RF group underwent complete AV block and pacemaker implantation. Over a mean follow-up period of 256,6 days there was a significative difference in AVNRT recurrences between cryoablation and RF patients(15% vs 3.4% P = 0.03) Catheter cryoablation of AVNRT minimizes the risk of inadverted AV block during ablation, and is a clinically effective alternative to RF ablation, with excellent acute success rate, and low incidence of recurrences in long term follow up. These results suggest that cryoablation may be considered as first-line approach, specially in younger people.