Systemic embolism with left atrial thrombus occurring four years after left atrial appendage closure in a patient with atrial fibrillation

Dear editor, The left atrial appendage (LAA) is the most common site for thrombus formation in patients with atrial fibrillation (AF).[1] We present the case of a patient with AF who underwent LAA closure (LAAC) with Watchman (Atritech, Boston Scientific, USA), in whom extracranial systemic embolic events (SEEs) with left atrial thrombus were observed after 4 years, and discuss relevant literature to improve the understanding of SEEs.