Clinical impact and indication of novel devices and surgical procedures for left atrial appendage closure

The left atrial appendage (LAA) has been shown to be the most common source for intracardiac thrombi that cause cerebral and systemic thromboembolism in patients with AF. From the end of 1950s, approximately 30 years before the maze procedure was performed as the first non-pharmacological rhythm control therapy for AF combined with LAA resection in 1987, surgical resection and closure of the LAA using a suture technique had been already performed in conjunction with mitral valve surgery to prevent thromboembolism in AF patients. Thoracoscopic resection of the LAA by stapling was introduced as an isolated procedure for non-valvular AF patients in 2000. Recently, a specially designed clip (AtriClip) was developed for epicardial non-resection closure of the LAA and now has been used for the patients with non-valvular AF and those undergoing off-pump coronary artery bypass grafting or other cardiac procedures with or without PV isolation to prevent postoperative thromboembolism. More recently, novel devices have been developed to occlude the LAA intracardially or intrapericardially. The intracardiac LAA closure device (Watchman) has been shown to prevent thromboembolic events and hemorrhagic complications due to anticoagulant therapy.

The risk of thromboembolism varies among different AF patients, depending on age, gender, type of AF, presence of underlying heart diseases, cardiac systolic and diastolic function, LA size, and other multiple parameters. The indication of LAA closure, selection of the optimal closure device and technique, and combination with a rate control ablation procedure should be discussed based on the risk of thromboembolism of the AF patients, and safety and efficacy of the occlusion devices.