Left atrial appendage isolation using percutaneous (endocardial/epicardial) devices: Pre-clinical and clinical experience

Atrial fibrillation (AF) is the most common arrhythmia in the elderly population and it is associated with a four-fold to five-fold increased risk of thromboembolic events. It was not until the mid-1950s that the left atrial appendage (LAA) was identified as the main location of thrombus formation, particularly in patients with non-valvular AF. In this review, we explain at some extent its embryology, anatomy and physiology, and as well as the clinical and pre-clinical trials published to date testing the safety and efficacy of most LAA closure devices. Among those devices, the most studied include the PLAATO system (ev3 Endovascular, Plymouth, MN), the Amplatzer cardiac plug (St Jude, Golden Valley, MN; St. Jude Medical, Minneapolis, MN), the WATCHMAN device (Boston Scientific, Plymouth, MN; Atritech Inc., Plymouth, MN), and the LARIAT device (SentreHEART, Palo Alto, CA). Similarly, newer LAA closure devices currently under investigation such as the Transcatheter Patch (Custom Medical Devices, Athens, Greece), AEGIS, and the Coherex WaveCrest (Salt Lake City, UT) will also be discussed. Future perspectives and the need for well-designed prospective studies between devices and new oral anticoagulant drugs are also proposed.