Left atrial appendage exclusion: state-of-the-art.

It is postulated that the source of thromboembolism in 90% of patients with non-valvular atrial fibrillation (AF) arises from the left atrial appendage (LAA). Anticoagulation with warfarin is the standard medical therapy for stroke prevention in patients with AF. However, chronic warfarin therapy is contraindicated in 14 to 44% of patients with AF who are at risk for stroke. Mechanical exclusion of the LAA may prevent thrombus formation in the appendage and hence reduce the risk of stroke. Recently, several studies of percutaneous transcatheter delivery of dedicated LAA exclusion devices such as the PLAATO device, Watchman device and the Amplatzer cardiac plug, have shown encouraging results as an alternative to warfarin therapy for selected patients. This article aims to review the current evidence for LAA exclusion in patients with AF.