Abstract 16591: Left Atrial Appendage Morphology and Thromboembolic Risk After Catheter Ablation for Atrial Fibrillation. Does Shape Really Matter?
Background: In patients with atrial fibrillation (AF), left atrial appendage (LAA) morphology has been suggested to modify risk for embolic events. In this case-control study we tested the hypothesis that embolic risk after AF catheter ablation (CA) is associated with LAA characteristics.
Methods: Of 2,069 patients who underwent CA, 15 patients had a stroke, transient ischemic attack (TIA) or systemic embolism during follow-up (excluding periinterventional events within 30 days). Those patients were matched for the CHA2DS2VASc score criteria with 115 thromboembolic event-free patients and CT (n=120) or MRI (n=10) data were compared. LAA volume, morphology (cactus, chicken wing, windsock, cauliflower) and takeoff of the superior or inferior edge in relation (higher or lower) to the respective takeoff of the adjacent pulmonary vein (PV) were determined. Follow-up was performed with clinical evaluation and serial 7 day-Holter ECG at 6, 12, 24 and 36 moths after CA. Oral anticoagulation was used according to current guidelines. AF recurrence was defined as any AF episode >30 seconds.
Results: After 27±15 months, 66% of the patients remained in sinus rhythm. Patients with embolic complications had a higher AF recurrence rate (73% vs. 28%, p=0.001), and a higher incidence of superior LAA takeoff (i.e. higher than the left superior PV; 80% vs. 37%, p=0.002) while LAA morphologies (27% cactus, 20% chicken wing, 20% windsock, 33% cauliflower vs. 23%, 20%, 19%, 38% respectively, p=0.98), inferior takeoff (73% vs. 54%, p=0.22), and LAA volume (7±3 vs. 8±4ml, p=0.35) were similar between groups. Logistic regression revealed AF recurrence (OR: 9.1, 95% CI: 2.4 to 33.7, p=0.001) and superior takeoff of LAA (OR: 6.7, 95% CI: 1.6 to 27.7, p=0.008) as independent predictors of thromboembolic events after AF-CA.
Conclusion: AF recurrence and higher LAA takeoff are associated with thromboembolism after AF catheter ablation while LAA morphology is not. These findings may have implications for post-ablation management.
- © 2013 by American Heart Association, Inc.