Heart team approach for left atrial appendage therapies: in addition to stroke prevention-is electrical isolation important?

Background The left atrial appendage (LAA) has been identified as a culprit for thromboembolic complications in the setting of atrial fibrillation (AF). LAA amputation has been integral to surgical treatment of AF since its early inception. As such, strategies to eliminate blood flow within the LAA have been developed and have proven their efficacy in preventing thromboembolic complications (1). These techniques are based on creating a mechanical barrier eliminating the LAA from blood flow, thereby preventing stasis that will cause thrombus formation. This mechanical barrier can be placed either endocardially (using either catheter-based techniques or sutures during open heart surgery) or epicardially. The main difference between these two approaches is that epicardial techniques involve the external application of mechanical force at the base of the LAA, hence truly closing the neck of LAA at its orifice, which over time leads to irreversible LAA fibrosis and subsequent disappearance (2). Only recently has the focus shifted towards the LAA, due to thromboembolic complications after oral anticoagulation in patients with elevated CHADS-VASC scores (1). But more importantly, the negative electrophysiological properties of the LAA might become a game changer as endocardial and epicardial LAA exclusion strategies produce different electrophysiological results.