BACKGROUND:: The aims of this study were to evaluate the relationship of the CHA2DS2-VASc score and risk categories with transesophageal echocardiographic (TEE) risk factors for thromboembolism and to compare the CHA2DS2-VASc and CHADS2 risk stratification schemes with respect to their ability to predict these risk factors in a multiethnic US population with nonvalvular atrial fibrillation. METHODS:: Transesophageal echocardiograms of 167 patients (mean age, 66.3 ± 11.6 years; 146 men [87%]; 100 whites [60%]; 40 Hispanics [24%]; 27 blacks [16%]) with nonvalvular atrial fibrillation were retrospectively reviewed for smoke, sludge, thrombus, and left atrial appendage (LAA) emptying velocity ≤20 cm/sec. The patientsʼ CHA2DS2-VASc and CHADS2 risk scores and categories were also calculated. RESULTS:: Any LAA abnormality, smoke, sludge, thrombus, and abnormal LAA emptying velocity were present in 45%, 38%, 13%, 3%, and 22% of patients, respectively. Heart failure (P < .001), age (P < .001 for age ≥75 vs ≤64 years, P = .013 for age 65–74 vs ≤64 years), and diabetes (P = .019) were independent predictors of LAA abnormalities, while ethnicity was not. The prevalence of TEE risk factors for thromboembolism increased with increasing CHA2DS2-VASc score and risk category. The CHADS2 risk categories of 35 patients (21%) were upgraded by the CHA2DS2-VASc scheme. Using the latter scheme, fewer patients were classified as at intermediate risk compared with the CHADS2 system (21 [13%] vs 46 [28%]). Patients classified as at low risk by either scheme had almost no TEE risk factors. Of 30 intermediate-risk patients by CHADS2 score upgraded to high risk using CHA2DS2-VASc score, eight (27%) had at least one TEE risk factor for thromboembolism. C-statistics, sensitivity, and specificity for predicting any LAA abnormality were 0.607 (95% confidence interval, 0.549–0.665), 92.0%, and 28.9% for CHA2DS2-VASc score and 0.685 (95% confidence interval, 0.615–0.755), 81.3%, and 54.2% for CHADS2 score. CONCLUSIONS:: CHA2DS2-VASc score is associated with TEE risk factors for thromboembolism in a multiethnic US population. Compared with CHADS2 score, it has increased sensitivity, decreased specificity, and lower ability for predicting TEE risk factors in this population.