A Real-World Comparison of Left Atrial Appendage Occlusion Using Two Commercially Available Devices

Abstract

Amplatzer and Watchman devices are the most used left atrial appendage occlusion (LAAO) systems. Real-world studies comparing their newer generation systems, the Amulet and Watchman FLX, are scarce. The goal of this study is to compare procedural and clinical outcomes of Amulet and Watchman FLX recipients. We analyzed the early adoption of the Amulet (n = 131) at a large health system between 9/2021 and 6/2023 and compared it to Watchman FLX (n=194) cases for procedural success, presence of peri-device leak (PDL) and device-related thrombosis (DRT) as well as clinical outcomes during follow-up. Procedural success rates were similar between the 2 devices (97.7% vs 96.4%, p = 0.5) with slightly longer procedural times for Amulet cases (69.4 ± 28.4 vs 57.2 ± 42.2 min, p = 0.002). Major (5.6% vs 2.6%, p = 0.24) and minor (16% vs 17.5%, p = 0.72) in-hospital complications were also statistically comparable. At 45 days, presence of PDL was not different (24.6% vs 23.4%, p = 0.81), with a mean PDL size of 2.4 ± 1.4 mm and 2.6 ± 1.1 mm (p = 0.51) in Amulet and Watchman FLX recipients, respectively, and 1 (0.8%) PDL > 5 mm in the Amulet group. Likewise, rates of DRT were comparable (3.3% vs 3.3%, p = 0.99). All-cause mortality (7.6% vs 3.8%, p = 0.24), cardioembolic (2.3% vs 1.1%, p = 0.6) and major bleeding (17.2% vs 10.6%, p = 0.13) events at 6 months were similar. In conclusion, despite early experience, the Amulet device exhibited comparable results to the Watchman FLX in a real-world setting. The learning curve with a new deployment technique likely accounts for longer procedural times with the Amulet.