Burden-based classification of atrial fibrillation predicts multiple-procedure success of pulmonary vein isolation

Catheter ablation of atrial fibrillation (AF) by means of pulmonary vein isolation (PVI) focuses on the PVs as the putative trigger of AF. However, which classification should be used to identify patients that are most suitable for PVI is uncertain. The aim of the study was to evaluate rhythm-, burden-, and anatomically-based classification schemes to predict success rates after up to two procedures of an ablation strategy strictly aimed at isolation of the PVs.

Patients with paroxysmal or non-longstanding persistent AF undergoing PVI-only ablation with the option of one repeat PVI in case of AF recurrence were included. An AF burden score (AFB) was determined based on frequency, episode duration, and number of previous cardioversions and then categorized as minimal, mild, moderate, or severe. Two- and three-dimensional anatomical assessment of the left atrium (LA) was performed based on pre-interventional imaging by computed tomography or magnetic resonance imaging.

Of 195 patients analyzed, 24 presented with recurrence after the last intervention (12%, median follow up: 16±11 months). In multivariable analysis, a more than 6-fold increase of risk for AF recurrence was identified for patients with a severe compared to a mild AFB [hazard ratio: 6.241 (95% confidence interval: 1.914-20.167, p=0.002)]. In contrast to univariable analysis, no other parameter was associated with recurrence in multivariable analysis.

Burden-based (AFB) classification was identified as a significant predictor for AF recurrence even after repeat PVI, while neither anatomical parameters nor the established rhythm-based classification of paroxysmal and persistent AF did.