Left atrial appendage closure for stroke prevention in atrial fibrillation: current status and perspectives

Graphical Abstract Rationale for left atrial appendage closure. Because of changing demographics, the number of atrial fibrillation patients is expected to double in industrialized countries within the next two decades. Patients with high risk for stroke have an indication for stroke preventive therapies consisting of either oral anticoagulation, percutaneous left atrial appendage closure in case of high bleeding risk, or surgical left atrial appendage closure in patients undergoing cardiac surgery. Several ongoing studies will more precisely define the optimal therapeutic approach for the individual patient. AF, atrial fibrillation, CABG, coronary artery bypass grafting; OAC, oral anticoagulation; LAAC, left atrial appendage closure. Atrial fibrillation (AF) is associated with an increased risk of stroke and systemic embolism, and the left atrial appendage (LAA) has been identified as a principal source of thromboembolism in these patients. While oral anticoagulation is the current standard of care, LAA closure (LAAC) emerges as an alternative or complementary treatment approach to reduce the risk of stroke or systemic embolism in patients with AF. Moderate-sized randomized clinical studies have provided data for the efficacy and safety of catheter-based LAAC, largely compared with vitamin K antagonists. LAA device iterations, advances in pre- and peri-procedural imaging, and implantation techniques continue to increase the efficacy and safety of LAAC. More data about efficacy and safety of LAAC have been collected, and several randomized clinical trials are currently underway to compare LAAC with best medical care (including non-vitamin K antagonist oral anticoagulants) in different clinical settings. Surgical LAAC in patients with AF undergoing cardiac surgery reduced the risk of stroke on background of anticoagulation therapy in the LAAOS III study. In this review, we describe the rapidly evolving field of LAAC and discuss recent clinical data, ongoing studies, open questions, and current limitations of LAAC.