Left atrial anatomy, atrial fibrillation burden, and P-wave duration-relationships and predictors for single-procedure success after pulmonary vein isolation.

Abstract

Atrial fibrillation (AF) is associated with changes in left atrial (LA) volume, but the relationship between LA size, AF burden, and electrical conduction behaviour is still uncertain. The aim of this study was to quantify the association and impact of these parameters on the single-procedure outcome after circumferential antral ablation for pulmonary vein isolation. Left atrial assessment was performed in 129 consecutive patients using pre-procedural imaging in three dimensions (sphericity, indexed volume), two dimensions (diameters), and from echocardiography in one dimension (long axis). Atrial fibrillation burden was classified based on the clinical assessment as paroxysmal and persistent and based on a validated scoring system including frequency, duration of AF episodes, and number of cardioversions into four grades (minimal, mild, moderate, and severe). P-wave duration and PR interval was measured on the 12-lead electrocardiogram at the end of the procedure. Atrial fibrillation burden score (AFB) was minimal (2%), mild (75%), moderate (9%), and severe (14%) and 65% had paroxysmal and 35% had persistent AF. The recurrence rate was significantly higher in patients with persistent AF, with higher AFB, with prolonged P-wave, and with an indexed LA volume > 55 mL/m2. In multivariable analysis, AFB (hazard ratio: 2.018(1.383-2.945), P > 0.001) and a prolonged P-wave (hazard ratio: 2.612(1.248-5.466), P = 0.011) were identified as significant predictors for AF recurrence. In our cohort of patients with symptomatic AF, the AFB and the P-wave duration but none of the anatomical parameter revealed to be independent predictors for AF/AT recurrence after circumferential antral pulmonary vein isolation.