Left atrial appendage morphology and silent cerebral ischemia in patients with atrial fibrillation

Abstract

Background: Left atrial appendage (LAA) is the major source of cardiac thrombi in atrial fibrillation (AF) and plays a major role in cardioembolic events.

Objective: To investigate the correlation between LAA morphology and the burden of silent cerebral ischemia (SCI) as a new thromboembolic risk marker in patients with AF.

Methods: A total of 348 patients with AF undergoing transcatheter ablation were enrolled. A cerebral magnetic resonance (MR) was performed to assess SCI burden, while LAA morphology was studied by MR or computed tomography and categorized as follows: cactus in 52 (14.9%) patients, chicken wing in 177 (50.9%), wind sock in 101 (29.0%), and cauliflower in 18 (5.2%).

Results: SCIs were detected in 295 (84.8%) patients, with a median number of lesions of 23. SCI burden was related to LAA complexity: 30.8% and 17.3% patients with cactus, 30.5% and 22.0% with chicken wing, 13.9% and 27.7% with wind sock, and 16.7% and 38.9% with cauliflower LAA morphologies were in the first and fourth quartiles of number of SCI per patient, respectively (P = .035). After adjustment for potential confounders, only age (β 0.12; 95% CI 0.08-0.16; P < .001), chicken wing (β -0.28; 95% CI -0.51 to -0.04; P = .021), wind sock (β 0.38; 95% CI 0.12-0.65; P = .005), and cauliflower (β 0.61; 95% CI 0.07-1.14; P = .026) LAA morphologies were significantly related to SCI burden.

Conclusion: LAA morphology relates to the burden of SCI in AF patients. Future research should corroborate if accessible methods (eg, echocardiography) are able to describe LAA morphology, permitting its use within universal thromboembolic risk predictors in AF patients.

Keywords: AF; Atrial fibrillation; CT; Cardiac computed tomography; Cardiac magnetic resonance; Cerebral magnetic resonance; LA; LAA; Left atrial appendage; MR; SCI; Silent cerebral ischemia; atrial fibrillation; computed tomography; left atrial appendage; left atrial/atrium; magnetic resonance; silent cerebral ischemia.