Abstract

BACKGROUND: Cryoablation is increasingly used to treat atrioventricular nodal reentry tachycardia (AVNRT) due to its safety profile. However, cryoablation may have higher recurrence than radiofrequency ablation (RFA) and the optimal procedural endpoint remains undefined.OBJECTIVE: The purpose of this study was to identify the association of cryoablation procedural endpoints with post-procedural AVNRT recurrence.METHODS: We performed a single-center, retrospective analysis of pediatric patients following successful first-time cryoablation for AVNRT between 1/1/2011 and 12/31/2019. Pre-ablation inducibility of AVNRT was recorded. Procedural endpoints, including slow pathway (SP) conduction (presence of jump or echo beats) with and without isoproterenol, were identified. Recurrence established from clinical notes and/or direct patient contact.RESULTS: Of 256 patients, 147(57%) were assessed on isoproterenol pre-cryoablation, and 171(47%) were assessed on isoproterenol post-cryoablation. Mean cryolesion time was 2586±1434 seconds. Following ablation, 104(41%) had some evidence of residual SP conduction. With median follow up time of 1.9[0.7-3.7] years, recurrence occurred in 14(5%) patients. Complete elimination of SP conduction (with and without isoproterenol) had a HR for recurrence of 1.26(95% CI 0.42-3.8, P=.68) on univariate analysis and 1.39(95% CI 0.36-5.4, P=.63) on multivariate analysis (including demographics, ablation time, 8mm cryocatheter and baseline inducibility).CONCLUSION: The observed AVNRT recurrence rate after cryoablation was comparable to RFA. The presence of residual SP conduction was not associated with recurrence. This suggests that jump or single echo beat may be an acceptable endpoint in AVNRT cryoablation.

View details for DOI 10.1016/j.hrthm.2021.09.031

View details for PubMedID 34601128