Left atrial remodeling and voltage-guided ablation outcome in persistent atrial fibrillation patients according to CHA2DS2-VASc score

Abstract

Background: CHA₂DS₂-VASc score-related differences have been reported in atrial fibrotic remodeling and prognosis of atrial fibrillation (AF) patients after ablation. There are currently no data on the efficacy of low voltage zone (LVZ)-guided ablation in persistent AF patients according to CHA₂DS₂-VASc score. We assessed in a cohort of persistent AF patients the extent of LVZ, the regional distribution of LA voltage and the outcome of LA voltage-guided substrate ablation in addition to PVI according to CHA₂DS₂-VASc score.

Methods: 138 consecutive persistent AF patients undergoing a first voltage-guided catheter ablation were enrolled. 58 patients with CHAD₂DS₂-VASc score ≥ 3 and 80 patients with CHAD₂DS₂-VASc score ≤ 2 were included. LA voltage maps were obtained using 3D-electroanatomical mapping system in sinus rhythm. LVZ was defined as < 0.5 mV.

Results: In the high CHAD₂DS₂-VASc score group, LA voltage was lower (1.5 [1.1-2.5] vs. 2.3 [1.5-2.8] mV, p = 0.02) and LVZs were more frequently identified (40% vs. 18%), p < 0.01). Female with CHA₂DS₂-VASc score ≥ 3 (p = 0.031), LA indexed volume (p = 0.009) and P-wave duration ≥ 150 ms (p = 0.001) were predictors of LVZ. After a 36-month follow-up, atrial arrhythmia-free survival was similar between the two groups (logrank test, P = 0.676).

Conclusions: AF patients with CHAD₂DS₂-VASc score ≥ 3 display more LA substrate remodeling with lower voltage and more LVZs compared with those with CHAD₂DS₂-VASc score ≤ 2. Despite this atrial remodeling, they had similar and favorable 36 months results after one single procedure. Unlike male with CHAD₂DS₂-VASc score ≥ 3, female with CHAD₂DS₂-VASc score ≥ 3 was predictor of LVZ occurrence.

Keywords: Atrial bipolar voltage; Atrial fibrillation; Atrial remodeling; Bipolar voltage map; CHAD2DS2-VASc score; Catheter ablation; Low voltage zone.