Background: Transcatheter ablation represents the first line therapy for atrio-ventricular nodal re-entrant tachycardia (AVNRT). Both radiofrequency (RF) and cryoablation (CRYO) have been shown to be effective, with a better safety profile for CRYO. Data on very long-term efficacy are scarces.
Purpose: to review our experience in AVNRT ablation performed in the last ten years and evaluate safety, efficacy and very long-term outcome of RF and CRYO.
Methods: We retrospectively analyzed all patients who underwent AVNRT ablation (RF or CRYO) between January 2013 and May 2023 at our centre. The majority of procedures were performed under electro-anatomical mapping (EAM) guidance to reduce radiation exposure. Acute efficacy endpoint was defined as slow pathway ablation, while long-term outcome was defined as the absence of AVNRT recurrence.
Results: A total of 387 consecutive patients (60,5% F; mean age 48 ± 19 years) were included; CRYO was performed in 241 patients (62%), RF in 131 patients (34%), hybrid approach (CRYO+RF) in 15 patients (4%). AVNRT induction was obtained during EPS in 295 cases (76%), in 25,4% after isoprotenerol administration. No significant differences for baseline characteristics were observed between the two groups except for age (CRYO: 42,2 ± 18 years vs RF 57,19 ± 16,5 years p <0.001). In pediatric population CRYO was performed in 93% of procedures. Figure 1 shows the distribution of RF/CRYO over 10 years at our centre, with a trend of significant increase in CRYO utilizations in the last years. Acute success was achieved in all 387 cases (100%; delta WP 28,5 ± 23,1 ms, delta AVN ERP 72,4 ± 44,7 ms). No permanent AV block or major periprocedural complications occurred, however transient AH prolongation was observed in 0.8% in CRYO pts vs 2,8% RF pts. The mean follow-up was 73±45 months, range 6-129 months. Overall long-term success rate was 93,3%, ranging from 91,3 % in CRYO and 96,6% in RF. Recurrence occurred in 26 cases (6,7%) after a median time of 20 months (4-40months). Recurrent AVNRT were treated with RF in the majority of cases, CRYO in 6 procedures, hybrid in only 1 case. Conclusions: Transcatheter ablation is a safe and effective therapy for AVNRT. Our very long-term outcome data confirmed very high success rate even after 10 years follow-up. The increasing choice for CRYO may be due to the increasing number of pediatric and young patient referred to our centre.
