Differences in the durability of left atrial posterior wall isolation based on the isolation process

Abstract

Purpose: The best strategy for durable left atrial posterior wall isolation (PWI) after completion of pulmonary vein isolation (PVI) is not yet determined. This study aimed to examine the differences in the durability of PWI based on the isolation process and the predictors of the reconduction of PWI.

Methods: Among the 221 patients (mean age, 65 ± 11 years) with consecutive non-paroxysmal atrial fibrillation (AF) who completed PVI and PWI, 50 patients undergoing repeat AF ablation were enrolled and divided into the following groups based on how PWI was achieved at the initial procedure: by only the first line on the roof and floor line (group A), by additional gap ablation to the first line or second liner ablation next to the first line (group B), and by adjunct ablation inside the PW revealing the earliest activation (group C).

Results: Reconduction of PWI occurred in 24 of the 50 patients (48%). The durability of PWI in groups A, B, and C was 81% (17 of 21 patients), 75% (6 of 8 patients), and 14% (3 of 21 patients), respectively (p < 0.01). In a multivariate analysis, the ablation inside the PW for PWI was the independent predictor of the reconduction of PWI (p < 0.001).

Conclusion: PWI achieved by the ablation inside the PW resulted in a high rate of reconduction. It may be necessary to aim to achieve the PWI without ablating the inside of the PW to prevent reconduction.

Keywords: Ablation; Atrial fibrillation; Durability; Epicardial connection; Lesion transmurality; Posterior wall isolation.