Abstract 18516: Regional Dysfunction of Left Atrial Appendage and its Association with Stroke in Atrial Fibrillation
Background: Atrial Fibrillation (AF) is associated with an increased risk of cardioembolic stroke. Previous studies demonstrate that the Left atrial appendage (LAA) is the most common site of intracardiac thrombus, and the LAA morphology alone may determine the risk of stroke. We aimed to determine the association between LAA regional dysfunction using novel, noninvasive, image-based motion-estimation CT (iME) and prior history of stroke in patients with AF.
Methods: Among the patients with history of AF referred for ablation who underwent pre-ablation CT with retrospective ECG gating, we identified 18 patients with a prior history of stroke or TIA, and 18 age- and gender-matched controls. The patients in AF at the time of CT were excluded. Four-dimensional motion vector field was estimated from reconstructed CT images using iME at every 5% RR interval. To assess myocardial deformation, area change ratio and area change rate were calculated over the endocardial surface of the LA and LAA. Univariate and multivariate comparisons were made by using binary logistic regression model.
Results: A total of 36 patients (mean age 67.6 ± 8.1 years, 66.7% male, 16.7% persistent AF) were included in the study. Univariate analysis showed that the LA pre-atrial contraction area change ratio and LAA maximum area change ratio were significantly lower (P= 0.02 and 0.04, respectively) in the stroke/TIA group compared to the control group. These changes remained statistically significant in multivariate analysis (P=0.03 and 0.04, respectively) after adjusting for age, sex, body mass index, LV ejection fraction, type of AF, and CHADS score.
Conclusions: LAA regional dysfunction is associated with stroke/TIA in patients with AF. LAA regional dysfunction detected by iME could represent a marker for stroke and a possible therapeutic target.
Author Disclosures: A.A. Alissa: None. Y. Inoue: None. J. Cammin: None. Q. Tang: None. E. Fishman: None. K. Taguchi: None. H. Ashikaga: None.
- © 2014 by American Heart Association, Inc.