Possible refinement of clinical thromboembolism assessment in patients with atrial fibrillation using echocardiographic parameters

Aim Some transoesophageal echocardiogram (TEE) findings are associated with an increased risk of stroke in patients with atrial fibrillation (AF). This study was designed to evaluate and compare the accuracy of CHADS2 and CHA2DS2-VASc in the prediction of these findings and test the additive value of transthoracic echocardiogram (TTE)-derived parameters as a possible refinement for these classifications. Methods and results Cross-sectional study of 405 consecutive patients who underwent TTE and TEE evaluation during AF. Stroke risk assessment was performed using the CHADS2 and CHA2DS2-VASc scores, alone and alongside with the addition of two TTE-derived parameters (left atrium area and left ventricle global systolic function). Comparisons regarding the presence of left atrial appendage thrombi (LAA T), dense spontaneous echo contrast (SEC), and left atrial appendage (LAA) low flow velocities (LFV) were performed using receiver operating characteristic curves. In low-risk patients, as assessed through the CHA2DS2-VASc score and CHADS2 and CHA2DS2-VASc scores plus echo parameters, no high-risk features were found on TEE. In subjects classified as low risk using CHADS2, this figure rose to 10%. No significant differences were found between CHADS2 and CHA2DS2-VASc in the prediction of LAA T, dense SEC, and LAA LFV. The addition of TTE-derived parameters to the previous clinical-risk scores resulted in improved prediction of the TEE endpoints. Conclusion These findings suggest that the use of TTE-derived parameters may be a valuable way of refining the available clinical risk schemes for the detection of surrogate markers of stroke. Follow-up studies using clinical endpoints will be necessary to confirm this hypothesis.