Correlation of CHADS2 and CHA2DS2-VASc scores with transesophageal echocardiography risk factors for thromboembolism in a multiethnic United States population with nonvalvular atrial fibrillation

Abstract

Background: The aims of this study were to evaluate the relationship of the CHA(2)DS(2)-VASc score and risk categories with transesophageal echocardiographic (TEE) risk factors for thromboembolism and to compare the CHA(2)DS(2)-VASc and CHADS(2) 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 patients' CHA(2)DS(2)-VASc and CHADS(2) 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 CHA(2)DS(2)-VASc score and risk category. The CHADS(2) risk categories of 35 patients (21%) were upgraded by the CHA(2)DS(2)-VASc scheme. Using the latter scheme, fewer patients were classified as at intermediate risk compared with the CHADS(2) 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 CHADS(2) score upgraded to high risk using CHA(2)DS(2)-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 CHA(2)DS(2)-VASc score and 0.685 (95% confidence interval, 0.615-0.755), 81.3%, and 54.2% for CHADS(2) score.

Conclusions: CHA(2)DS(2)-VASc score is associated with TEE risk factors for thromboembolism in a multiethnic US population. Compared with CHADS(2) score, it has increased sensitivity, decreased specificity, and lower ability for predicting TEE risk factors in this population.