Posterior box isolation as an adjunctive ablation strategy during repeat ablation with the second-generation cryoballoon for recurrence of persistent atrial fibrillation: 1-year follow-up

Abstract

The creation of a posterior box isolation of the left atrium (LAPWI) in addition to pulmonary vein isolation (PVI) with the second-generation cryoballoon (CB-A) seems to offer promising clinical outcome in patients affected by persistent atrial fibrillation (PersAF). This work aims to study the clinical outcome of an ablation strategy based on the creation of a LAPWI during repeat procedures for recurrent AF after an index CB-A procedure for PersAF. A total of 33 patients having undergone a repeat procedure consisting in redo PVI plus LAPWI for recurrent PersAF with the CB-A after an index PVI ablation were retrospective included in our study. Electrical reconnection could be documented in 18 veins (13%). The LAPW was successfully isolated solely by CB-A ablation in 30 out of 33 (91%) patients; in the remaining 3 patients, isolation of the LAPW was completed by focal tip-irrigated RF ablation. The mean number of CB-A applications required for the superior portion of the LAPW and the inferior portion of the LAPW creation were 5.4 ± 0.9 and 4 ± 0.6, respectively. After a mean follow-up of 11.8 ± 3months, 28 patients (85%) did not experience recurrence of any atrial arrhythmias during follow-up, without the need of further ablation or class I or III AADs. Left posterior wall isolation with the CB-A is feasible and safe during repeat ablation procedures for recurrent PersAF. In our study, the 12-month freedom from any arrhythmia was 85% following this ablation strategy.