Volume and morphology of left atrial appendage as determinants of stroke subtype in patients with atrial fibrillation

BACKGROUND Atrial fibrillation (AF) is a leading cause of stroke, but not all cases of stroke in patients with AF are due to AF. OBJECTIVE The purpose of this study was to determine whether morphometric or volumetric parameters of left atrial appendage (LAA) would be related to the development of cardioembolism in subjects with AF. METHODS A total of 433 consecutive patients with acute ischemic stroke underwent multidetector cardiac computed tomography (MDCT). Of these patients, 88 with AF were divided into cardioembolic stroke (CES; n = 57) and non-CES (n = 31) groups, and 95 age- and sex-matched patients with non-CES without AF served as controls. Clinical factors, echocardiographic findings, and MDCT parameters were evaluated. RESULTS Brain infarct volume, LAA orifice diameter, and LAA volume were larger in patients with CES with AF than in those with non-CES with AF (P < .05 in all cases), but no difference was observed between patients with non-CES with AF and those with non-CES without AF. MDCT and echocardiographic parameters of left atrial (LA) dysfunction were different depending on the presence of AF but not between patients with CES with AF vs non-CES with AF. After adjusting for covariates, LAA orifice diameter (odds ratio 1.19, 95% confidence interval 1.06-1.33, P = .004) and LAA volume (odds ratio 12.20, 95% confidence interval 2.58-57.79, P = .002) were independently associated with CES with AF, as was infarct volume. CONCLUSION In patients with AF, LAA orifice diameter and LAA volume, but not left atrial dysfunction, were determinants of CES and were useful for stratifying noncardioembolic risk in patients with AF.