Hyperuricemia and Transesophageal Echocardiographic Thromboembolic Risk in Patients With Atrial Fibrillation at Clinically Low-Intermediate Risk

Background: There is no clear consensus on thromboprophylaxis in patients with nonvalvular atrial fibrillation (AF) at low-intermediate thromboembolic risk. Although hyperuricemia is a risk factor for cardiovascular diseases, the relationship between serum uric acid (UA) levels and thromboembolic risk has not been fully elucidated in patients with AF. Methods and Results: Serum UA levels and the score for congestive heart failure, hypertension, age, diabetes mellitus, prior stroke/transient ischemic attack, vascular disease and sex (ie, CHA(2)DS(2)-VASc score) were determined in 470 patients with nonvalvular AF who underwent transesophageal echocardiography (TEE) to evaluate their risk of thromboembolism. Serum UA levels were similar between the low-intermediate risk (CHA2DS2-VASc score=0 or 1) and high-risk (>= 2) groups, although serum D-dimer levels were lower in the low-intermediate risk than in the high-risk group. Among patients at low-intermediate risk, serum UA levels were higher in those with TEE thromboembolic risk (TEE risk: low left atrial appendage flow, spontaneous echo contrast, thrombi, or aortic atherosclerosis) than in those without TEE risk. On multivariate analysis, the serum UA level was an independent predictor of TEE risk in AF patients at low-intermediate risk (odds ratio, 1.45; 95% confidence interval 1.09-2.00; P=0.016). Conclusions: The serum UA level was associated with thromboembolic risk on TEE in patients with nonvalvular AF at low-intermediate risk stratified by clinical risk factors.