P25-1 - Left Atrial Function: A Predictor of Poor Outcome After Catheter Ablation for Atrial Fibrillation

Abstract

Background: Left atrium (LA) have reservoir, booster and conduit function. We investigated which LA function play the most important role for atrial fibrillation (AF) recurrence after catheter ablation (CA). Methods: We studied 64 patients (39 males, age 65 ± 8 yrs) who underwent CA for non-paroxysmal AF. Transthoracic echocardiography (TTE) was performed during sinus rhythm at the next day after CA. LA functions were calculated using the following formula: (1) Reservoir function = {[maximum LA volume (LAVmax) − minimum LA volume (LAVmin)]/LAVmin} × 100, (2) Booster function = {[Pre-A volume (LAVpre-A) − LAVmin]/LAVpre-A} × 100, LAVpre-A was defined as LA volume at the onset of the P-wave on electrocardiogram. (3) Conduit function = [(LAVmax − LAVpre-A)/LAVmax] × 100. Results: Recurrent AF was detected in 24/64 (38%) during the follow-up period (11.5 ± 7.0 month). Univariate analysis revealed lower reservoir function, decreased booster function, larger LA diameter, and elevated E wave as significant variables. On multivariate analysis, booster function was only independently associated with recurrent AF (P = .0279, OR 1.140 for each 1% decrease in LA booster function, 95%CI 1.024–1.301). Moreover, patients with decreased LA booster function (<10.6%) had a higher risk of recurrent AF (log-rank P = .0009). Conclusion: LA booster dysfunction immediately after the CA might predict a recurrence after CA for non-paroxysmal AF.