Which Device for LAA Closure? Takeaways from SWISS-APERO Trial

The SWISS-APERO trial1 is one of the first studies to compare device performance and safety outcomes between the Amulet device and the newer generation Watchman FLX. Enrolling fewer patients than the contemporary Amulet-IDE study,2 which compared Amulet and Watchman 2.5, more than 77% of patients of the Watchman group in the SWISS-APERO study received the newer generation Watchman FLX device. The study did not reach predefined superiority of Amulet compared to Watchman devices in its primary outcome as a composite of justified crossover to the non-randomly allocated device and left atrial appendage (LAA) patency at 45-day with coronary computed tomography angiography (67.6% vs. 70%, p = 0.71). Fewer mixed leaks but more intradevice leak was detected in the Amulet group. Peridevice leak evaluated by transesophageal echocardiography was also significantly lower in the Amulet group (13.7% vs. 27.5%, p = 0.02). Despite better device performance, Amulet was found to have more procedure related complications, mostly in the form of Bleeding Academic Research Consortium (BARC) 3-5 major bleeding. The ultimate goal for left atrial appendage (LAA) occlusion is to eliminate leaks of any form. The clinical significance of the lower leaks with Amulet needs to be investigated in larger, prospective randomized trials with adequate follow-up. However, the SWISS-APERO study has established that Amulet is a solid alternative to Watchman for operators to consider in percutaneous LAA occlusion procedures.


  1. Galea R, De Marco F, Meneveau N, et al. Amulet or Watchman device for percutaneous left atrial appendage closure: primary results of the SWISS-APERO randomized clinical trial. Circulation 2021;Nov 6:[Epub ahead of print].
  2. Lakkireddy D, Thaler D, Ellis CR, et al. Amplatzer Amulet left atrial appendage occluder versus Watchman device for stroke prophylaxis (Amulet IDE): a randomized, controlled trial. Circulation 2021;144:1543-52.

Clinical Topics: Noninvasive Imaging, Echocardiography/Ultrasound, Arrhythmias and Clinical EP

Keywords: TCT21, Transcatheter Cardiovascular Therapeutics, Atrial Appendage, Echocardiography, Transesophageal, Prospective Studies, Follow-Up Studies, Computed Tomography Angiography, Hemorrhage

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