Abstract 4632: Left Atrial Size and Advancing Age Predict the Need to Restart Drug Therapy after AF Ablation to Maintain AF Control

Abstract

Background : While many patients (pts) remain free of atrial fibrillation (AF) without anti-arrhythmic drug(AAD) therapy after ablation, some pts require re-initiation of medications to control AF long-term. Factors associated with need for reinstituting AAD have not been identified. Methods: A total of 578 pts who underwent AF ablation and demonstrated AF control for at least 12months were included in this study. The ablation included proximal pulmonary vein (PV) isolation with entry and exit block and elimination of non PV triggers. AAD were reinitiated if with ECG documented AF recurrence after the 2 month blanking period. Confirmation of AF control was based on symptoms and transtelephonic ECG monitoring at 6 mos, 12 mos, and with symptoms. Clinical variables were compared between each group by univariate analysis to determine if significant differences existed. Significant parameters were included in a multivariate analysis to determine interaction between variables. Results: Table 1 delineates clinical parameters included in the analysis, with unadjusted P values for each variable. Multivariate analysis with forward and backward regression identified larger LA size and advancing age as only factors which correlated with the need for AAD therapy after ablation to maintain AF control. Conclusions: Increased LA size and advancing age are clinical parameters which suggest progressive fibrosis of the LA. In our analysis, these two variables strongly predicted the need to restart AAD therapy after proximal PV ablation and elimination of non PV triggers in order to maintain long-term control of AF. Table 1