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Close up view of the WATCHMAN implant on a blue background

SEAL FLX

The first study to exclusively compare left atrial appendage (LAA) closure performance between the WATCHMAN FLX™ LAAC Device and Amplatzer™ Amulet™ device using cardiac computed tomography (CT).

Assessing LAA Occlusion: WATCHMAN FLX Device vs. Amulet

Conducted at Aarhus University Hospital in Denmark, this 300-patient, single-center, retrospective study evaluated left atrial appendage (LAA) occlusion performance following WATCHMAN FLX or Amplatzer Amulet implantation, between 2017 and 2020. 


 

Study design

  • Complete LAA occlusion is defined as no visible peri-device leak (PDL) and the absence of contrast patency in the distal LAA 
  • 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 occlusion* based on CT imaging


 

WATCHMAN FLX Device demonstrated statistically superior complete occlusion* vs. Amulet (p<0.001) 

Complete occlusion* based on CT imaging

Complete LAA Occlusion graph

WATCHMAN FLX Device achieves full seal in all CT views, providing confident closure of the LAA  

CT imaging confirms complete occlusion1

CT imaging coronal

Coronal

CT imaging device face

Device face

CT imaging sagittal

Sagittal

Peri-device leak by LAA anatomy 

Peri-device leak by LAA anatomy chart

The WATCHMAN FLX Device demonstrated superior complete occlusion across all anatomies analyzed.* 

Leak size (mm2) 

Leak size (mm2) chart

Amulet exhibited a significantly greater leak size than the WATCHMAN FLX Device (p=0.019). 


 

The WATCHMAN FLX Device achieves a stronger seal with its one-component design 

Simplified sizing

10-30% compression

WATCHMAN FLX Device

Single landing zone and overlapping treatment ranges

closeup of the Amplatzer Amulet measurements

Amplatzer Amulet2

Complicated, mis-matched measurements 

Simplified placement

an image of the WATCHMAN device being implanted in the heart

WATCHMAN FLX Device

Precision placement control 

closeup of the Amplatzer Amulet placement

Amplatzer Amulet3

Trade-off between disc and lobe placement 

Simplified assessment

closeup of the WATCHMAN implant

WATCHMAN FLX Device1

Full visibility

closeup of the Amplatzer Amulet hidden leaks

Amplatzer Amulet1

Hidden leaks

Learn more about the WATCHMAN FLX™ Pro LAAC Device

Explore the WATCHMAN FLX Pro Device

* 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) 

References

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, https://doi.org/10.1093/ehjci/jev067