Residual leaks following percutaneous left atrial appendage occlusion: assessment and management implications

Left atrial appendage (LAA) closure for stroke prevention in the setting of non-valvular atrial fibrillation is an alternative to oral anticoagulation in patients with increased bleeding risk. It allows similar reduction in thromboembolic events, in particular stroke, compared to warfarin. A common clinical dilemma is the management of patients with peri-device leak after LAA occlusion. This has been documented in both percutaneous as well as surgical approaches. The specific definitions of leak severity, and the longer-term clinical implications are poorly understood. Here we review the mechanisms of incomplete occlusion for the different percutaneous closure devices, the data regarding thromboembolic risk in patients with incomplete appendage closure for both percutaneous and surgical strategies, and provide recommendations for management in these patients.