Background: Silent brain infarction (SBI) is an independent risk factor for subsequent symptomatic stroke in general population. Although aortic stenosis (AS) is also known to be associated with increased risk of future symptomatic stroke, little is known regarding the prevalence of SBI and its risk factors in patients with severe AS.Methods: This study population consisted of 85 neurologically asymptomatic patients (mean age, 75 ± 7 years) with severe AS (mean aortic valve area, 0.70 ± 0.14 cm) who were scheduled for surgical aortic valve replacement. All patients underwent brain magnetic resonance imaging to screen for SBI prior to the day of surgery. Comprehensive transthoracic and transesophageal echocardiography were performed to evaluate left atrial (LA) abnormalities such as LA enlargement, spontaneous echo contrast, or abnormal LA appendage emptying velocity (< 20cm/s) and complex plaques in the aortic arch defined as large (≥ 4mm), ulcerated or mobile plaques.Results: Forty (47%) patients showed SBI. In univariate analysis, hypertension, lower estimated glomerular filtration rate (eGFR), complex arch plaque, and CHA2DS2-VASc score were significantly associated with SBI (P < 0.05), whereas the parameters of LA abnormality were not. Multiple logistic regression analysis indicated that CHA2DS2-VASc score (odds ratio, 1.58; 95% CI, 1.09-2.29; P < 0.05) and eGFR (odds ratio, 0.98; 95% CI, 0.96-0.99; P < 0.05) remained independently associated with SBI. When patients were divided into 4 groups according to CHA2DS2-VASc score and eGFR, the group with higher CHA2DS2-VASc score (≥ 4) and lower eGFR (< 60 ml/min/1.73m) had greater risk of SBI compared with the group with lower CHA2DS2-VASc score (< 4) and higher eGFR (≥ 60 ml/min/1.73m) (relative risk, 4.17; 95% CI, 1.58-11.02; P < 0.05).Conclusions: AS is associated with a higher prevalence of SBI. Higher CHA2DS2-VASc score and renal impairment, rather than LA abnormalities, are associated with SBI in patients with severe AS. The combination of CHA2DS2-VASc score and renal impairment has additional predictive value for SBI. Intensive intervention for these high-risk patients may avoid SBI and consequently reduce the risk of subsequent stroke.