Percutaneous Left Atrial Appendage Closure

Left atrial appendage (LAA) closure is a rapidly emerging field in stroke prevention for patients with atrial fibrillation. Several percutaneous and surgical devices are now approved worldwide, and many more are in clinical development and being evaluated in research trials. The current most widely used endovascular devices worldwide are the WATCHMAN and Amplatzer Cardiac Plug (Amulet, 2nd generation) devices, which received CE Mark in 2005 and 2008, respectively. In addition, the WATCHMAN device recently received FDA approval in March 2015 in the United States for patients at high-risk of stroke who are suitable for warfarin, and who have appropriate rationale for non-pharmacologic stroke prevention alternative.

Results from several early pre-clinical and clinical research studies have ascertained the safety and efficacy of percutaneous LAA closure in stroke prevention, including randomized controlled trials with the WATCHMAN device that showed superiority in comparison to warfarin. Further pre-clinical and clinical research trials and data are rapidly accumulating with this and other devices. Although these initial randomized trials evaluated patients who are candidates for oral anticoagulation, the current predominant real-world application for this procedure is mostly restricted to patients who have contraindications to anticoagulation. Even this restricted indication have substantial implications on application of this procedure, since over 40% of patients with atrial fibrillation who have guideline indications for anticoagulation are not on anticoagulation because of contraindications, intolerance, or were felt to be poor candidates for anticoagulation. Broader application to patients without these restrictions is anticipated as this procedure and technology matures, and further clinical trial data becomes available.

In summary, LAA closure has evolved to become an important alternative to oral anticoagulation in patients with atrial fibrillation, and is expected to remain a dominant technology for stroke prevention with this prevalent arrhythmia.