Prediction of spontaneous echocardiographic contrast within the left atrial appendage in cardiac computed tomography of patients with atrial fibrillation

This study aimed to assess the predictors of spontaneous echocardiographic contrast (SEC) using left atrial appendage (LAA) findings in cardiac computed tomography (CT) of patients with atrial fibrillation (AF). We retrospectively analyzed cardiac CT findings of the LAA, including morphology, volume, and filling defects, of 641 patients who underwent transesophageal echocardiography (TEE) prior to pulmonary vein isolation (PVI) from January 6, 2013 through December 16, 2019 at our institution. We investigated potential associated factors that might be predictors of SEC using cardiac CT findings and computed a receiver operator characteristic, choosing a threshold value at which the likelihood of SEC could be predicted based on the LAA volume indexed for body size. SEC correlated significantly with indexed LAA volume (P < 0.001; odds ratio [OR], 1.31; 95% confidence interval [CI], 1.17–1.48) of 7.75 cm³/m² or greater (sensitivity, 76.0%; specificity, 57.7%), LAA early filling defect (P = 0.005; OR, 2.72; 95% CI, 1.35–5.48), a history of persistent AF (P < 0.001; OR, 3.81; 95% CI, 1.86–7.80), and LAA flow velocity (P < 0.001; OR, 0.97; 95% CI, 0.96–0.99). Findings of LAA in cardiac CT can allow for the noninvasive estimation of SEC to determine the need for additional TEE investigation and the need to obtain additional information for risk stratification and management of thromboembolic events in patients with AF.