Left atrial appendage occlusion: A mechanical approach to treat patients with high thrombotic risks in whom anticoagulation is contraindicated

Abstract: LAAO has been a relatively mainstream option as an alternative to oral anticoagulation in patients ineligible for same since 2010. Since then evidence has increased incrementally over the years proving relative efficacy. Currently LAAO carries a 2B indication (ESC/AHA) for patients ineligible for the standard care of anticoagulation.

Objective: The aim of this MD is to outline the issues surrounding AF, the thromboembolic pathophysiology, and the historical treatment options available. It will primarily address the alternative treatment of LAAO, going into the history and development of some of the main devices including trial data. It will showcase the developmental processes involved in engineering new devices in animal studies. Finally, and more importantly, it will present the retrospective registry data from Beaumont hospital as a study of real world efficacy of LAAO.

Methods: A retrospective search was made from all recorded implants in Beaumont Hospital since 2005 to December 2021. A total of 272 out of 400 plus patients were included, with a follow-up period set at 5 years. Mortality data was obtained from various sources, and key end point events from hospital charts. Analyses for outcomes were measured across device type, AF type, gender, and some echo parameters. Primary endpoints include all-cause mortality, CV event and all-cause CVA events. Statistical analysis was calculated using Data Tab and main outcomes were plotted against a Kaplan-Meier curve with Cox proportional hazards. Regression analysis was used to potentially assess for causality on some echo parameters.

Results: 5 year MACE events (n=174) demonstrated an all-cause mortality rate of 87 (9.9 per 100PY), cardiovascular mortality of 18 (2 per 100PY), all CVA Events at 24 (2.7 per 100PY) Non-Fatal MI at 11 (1.2 per 100PY) Fatal MI at 10 (1.1 per 100PY ) and embolic CVA at 9 (1 per 100PY).These findings are consistent with known international registries.