Abstract 16003: Atrial Fibrillation Complicated With Thrombus Formation in LA Appendage During Anticoagulation: Incidence, Clinical Characteristics and Efficacy of Catheter Ablation
Backgrounds: Although CHADS2 score has been widely accepted as a risk stratification method of cerebral embolism in patients (pts) with atrial fibrillation (AF), characteristics of AF with LA appendage (LAA) thrombus (LAA-T) formation identified by trans-esophageal echocardiography (TEE) have not been precisely described.
Purposes: To assess clinical characteristics and efficacy of catheter ablation (CA) in AF pts with LAA thrombus.
Methods: In consecutive 1547 AF pts (paroxysmal 1020, non-paroxysmal 527) who had been anticoagulated for more than 4 weeks, TEE was performed within 24 hours before scheduled CA procedure. They were divided into 2 groups according to presence (Group-1: 23 pts (1.5%)) or absence of LAA-T (Group-2: 1524 pts (98.5%)). In Group-1, strengthened warfarinization (PT-INR>2.5) was initiated soon after thrombus identification and CA was performed only after confirmation of thrombus dissolution on follow-up TEE. Clinical characteristics and post-ablation clinical outcomes were compared between the groups.
Results: At the time first LAA-T was identified, Group-1 pts were taking warfarin in 13, dabigatran in 8 (220mg/day in all) and other NOACs in 2 pts. Group-1 exhibited significantly higher incidence of non-PAF (87 vs 33%; P<0.0001), higher HbA1C and BNP level, lower LAA flow velocity and higher incidence of spontaneous echo contrast on TEE (67 vs. 7%; P<0.0001), larger LA diameter (45±5 vs. 40±6; P=0.0004), lower LV ejection fraction (69±10 vs. 73±9; P=0.04) and higher CHADS2 score (1.8±1.0 vs. 1.0±1.0; P<0.0001) than Group-2. In Group-1, CHADS2 score was 0-1 in 8 pts (35%). Multivariate logistic regression analysis revealed that non-paroxysmal AF was the only independent predictor of LAA-T formation (OR: 6.3 (95% CI: 1.01-124.61), P=0.048). In 14 Group-1 pts, LAA-T dissolution was confirmed after sufficient warfarinization. After 1.4±0.6 CA procedures, Group-2 exhibited significantly higher recurrence-free survival than Group-1 (94.4 vs. 92.9%; P<0.0001) during follow-up period of 398±245 days after last CA procedure.
Conclusions: Non-paroxysmal AF was the independent predictor of LAA-T formation. Efficacy of CA in those with history of LAA-T formation was inferior to that in those without.
Author Disclosures: K. Otomo: None. K. Takizawa: None. N. Inoue: None. T. Meguro: None.
- © 2014 by American Heart Association, Inc.