The left atrial appendage: from embryology to prevention of thromboembolism.

The left atrial appendage (LAA) is the main source of thromboembolism in patients with non-valvular atrial fibrillation (AF). As such, the LAA can be the target of specific occluding device therapies. Optimal management of patients with AF includes a comprehensive knowledge of the many aspects related to LAA structure and thrombosis. Here we provide baseline notions on the anatomy and function of the LAA, and then focus on current imaging tools for the identification of anatomical varieties. We also describe pathogenetic mechanisms of LAA thrombosis in AF patients, and examine the available evidence on treatment strategies for LAA thrombosis, including the use of non-vitamin K antagonist oral anticoagulants and interventional approaches.