Abstract 12160: Predicting Atrial Fibrillation Recurrence After Thoracoscopic Ablation by Left Atrium Appendage Emptying Velocity

Introduction: Totally thoracoscopic ablation (TTA) is the latest tool for in patient with persistent or long-standing atrial fibrillation (AF). Left atrium appendage (LAA) emptying velocity is known related with maintenance sinus rhythm after successful cardioversion and catheter ablation. There were no studies about the value of LAA emptying velocity in thoracoscopic ablation since now. Hypothesis: We assessed the hypothesis that LAA emptying velocity could predict AF recurrence also in patient who underwent TTA. Methods: Between February 2012 and March 2015, 150 patients underwent TTA in a tertiary center in South Korea. The primary outcome was AF recurrence detection in either 12-lead electrocardiogram or holter during 3 years after TTA, excluding initial 3 months of blanking period. After baseline characteristics comparison between no AF recurrence group and AF recurrence group, main contributing factor for AF recurrence was analyzed with multivariable cox regression. Additionally, time-dependent ROC (receiver operating characteristic) analysis was done to estimate predictive power of LAA emptying velocity for AF recurrence. Results: Proportion of paroxysmal AF and LAA emptying velocity were higher in no AF recurrence group. LA volume size was larger in AF recurrence group. Except these values, other clinical characteristics like age, sex, underlying disease, CHA 2 DS 2 -VASc score, history of RFCA, use of antiarrhythmic drug or surgical method were not significantly different. In multivariable cox regression, female sex (HR 2.474, 95% CI [1.036-5.905], p value=0.041) and LAA emptying velocity (HR 0.941, 95% CI [0.915-0.967], p value<0.001) were meaningful contributing factor for AF recurrence. Also, LAA emptying velocity showed modest degree predictive performances for predicting AF recurrence (AUC 0.754, 95% CI [0.675 - 0.834])(figure 1). Conclusions: In conclusion, LAA emptying velocity could predict AF recurrence after TTA.