Cho MS, Choi KJ, Kim M, et al. - Researchers undertook this single-center cohort analysis to determine whether left atrial enlargement (LAE) on transthoracic echocardiography (TTE) could discriminate who need anticoagulation treatment among non-valvular atrial fibrillation (NVAF) patients with low/borderline clinical embolic risk. This study included 6,602 patients (median age, 56 years, 70.0% male). Following multivariable adjustment, a higher risk of thromboembolic event was observed in patients with moderate-severe LAE vs those with no LAE. This finding persisted in a subgroup study of anticoagulant-naïve patients. Patients with low clinical embolic risk and moderate-severe LAE did not have a different rate of thromboembolic events when compared with those with high clinical embolic risk without LAE. Overall, among NVAF patients at low/borderline clinical embolic risk, moderate-severe LAE on TTE was concluded to be a significant predictor of thromboembolic events.