close up of WATCHMAN FLX device on white background


The first head-to-head comparison of occlusion properties of the WATCHMAN FLX device and the Amplatzer Amulet device using cardiac computed tomography (CT).

Study Design

  • Single-center, retrospective study of LAAO implantation at Aarhus 
 University Hospital (Denmark) between 2017-2020.
    1st cohort: Amplatzer Amulet (n=150) 2017 – 2019
    2nd cohort: WATCHMAN FLX (n=150) 2019 – 2020
  • Cardiac CT was performed 8 weeks after LAAO
Primary Outcome Complete Seal* Based on CT Imaging

WATCHMAN FLX Demonstrated Statistically Superior Complete Occlusion* vs Amulet (p<0.001)

Complete Occlusion*

Complete LAA Occlusion graph

Complete Occlusion* on CT Imaging1

The Superior Complete Occlusion* of the WATCHMAN FLX Device Was Consistent Across All Anatomies Analyzed

Peri-Device Leak
Peri Device Leak graph

Leak Measurements were Significantly Larger with Amulet than WATCHMAN FLX (p=0.019)

Leak Size (mm2)
Peri Device Leak graph

WATCHMAN FLX’s One-Component Design Translates to Clear Sealing Advantages

Simplified Sizing


WATCHMAN FLX sizing icon

Single Landing Zone and Overlapping Treatment Ranges


Amplatzer Amulet sizing icon

Complicated, Mis-Matched Measurements

Simplified Placement


WATCHMAN FLX placement icon

Precision Placement Control


Amplatzer Amulet placement icon

Trade-off Between Disc and Lobe Placement

Simplified Assessment


WATCHMAN FLX assessment icon

Full Visibility


Amplatzer Amulet assessment icon

Hidden Leaks

WATCHMAN FLX device with decorative teal overlay

1. Korsholm-K et al. Left atrial appendage sealing performance of the Amplatzer Amulet and Watchman FLX device. J Interv Card Electrophysiol. 2022 Aug 11. doi: 10.1007/s10840-022-01336-4.
2. Lakkireddy, Amulet Tips and Tricks in Simple and Complex Anatomy, TVT 2018.
3. Saw, Cardiac CT angiography for device surveillance after endovascular left atrial appendage closure, European Heart Journal - Cardiovascular Imaging, Volume 16, Issue 11, November 2015, Pages 1198–1206,
* Complete LAA occlusion defined as no visible peri-device leak (PDL) and absence of contrast patency in the distal LAA (LAA/left atrium Hounsfield ratio <0.25)