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Meta-analysis

Key outcomes of the WATCHMAN FLX™ LAAC Device vs. Amplatzer™ Amulet™ Occluder

Meta-analysis reveals superior safety and better left atrial appendage (LAA) closure with the WATCHMAN FLX Device vs. Amulet

Meta-analysis of 4,186 patients from 21 studies, examines how the WATCHMAN FLX Device compares to Amulet in acute safety and procedural success, short-term outcomes, and overall device performance.1*

Study design

  • 3,187 Amulet implants 
  • 999 WATCHMAN FLX Device implants 
  • CHA2DSC2-VASc: 4.3±1.5 for Amulet  
  • CHA2DSC2-VASc 4.2±1.5 for WATCHMAN FLX Device 
  • The first imaging study, conducted within three months, was used to assess peri-device leaks greater than 5mm and device-related thrombosis (DRT). 

Safety endpoint

The safety endpoint included the occurrence of death, stroke, major bleeding, myocardial infarction, major vascular complications, device embolization, or pericardial effusion, within seven days after the procedure.


 

The WATCHMAN FLX Device outperformed Amulet in safety, procedural success, and LAA closure, in the largest, head-to-head comparison.

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Superior procedural safety

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Higher procedural success

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Better LAA closure

Key results

Safety

The WATCHMAN FLX Device demonstrated superior safety with a significantly lower incidence of peri-procedural complications (p<0.01). 

Adverse Events graph

Key clinical outcomes  

The WATCHMAN FLX Device proved to be superior to Amulet across key measures: 

  • Primary safety endpoint: 0.6% WATCHMAN FLX Device vs. 4.7% Amulet (p<0.01)  
  • Overall pericardial effusion/tamponade: 0.1% WATCHMAN FLX Device vs. 2.5% Amulet (p<0.01)  
  • Clinically relevant pericardial effusion/tamponade: (0.01% WATCHMAN FLX Device vs. 0.7% Amulet, p=0.01)  
  • Peri-procedural major/intracranial bleeding: 0.1% WATCHMAN FLX Device vs. 2.3% Amulet (p=0.01)  
  • Device embolizations: zero cases with WATCHMAN FLX Device vs. 15 cases with Amulet   
  • Device-related thrombosis (DRT): 1% WATCHMAN FLX Device vs. vs 1.6% Amulet   
  • Mortality or stroke: No difference observed between groups  

Simplicity

The WATCHMAN FLX Device delivers streamlined procedures with high procedural success rates, showcasing its ease of use, safety and reliability.

99.9%

The WATCHMAN FLX Device exhibited a trend of higher procedural success (p=0.08).

Procedural success was achieved in 99.9% of WATCHMAN FLX patients (99.4% for Amulet, p=0.08). 

Seal

Delivering stronger LAA closure, the WATCHMAN FLX Device showed a trend towards more effective appendage closure, with significantly fewer peri-device leaks greater than 5mm compared to Amulet (0.01% vs. 0.34%, p=0.06) 

Rate of leaks greater than 5mm

Peri Device

Learn about the SEAL FLX study and key insights into the superior occlusion of the WATCHMAN FLX Device.

Explore SEAL FLX study results

* Meta-analysis is a statistical technique used to systematically merge the findings of previous studies to calculate an overall or ‘absolute’ effect.

References

1. Della Rocca, D., Magnocavallo, M., Gianni, C., Horton, R., Biase, L., Natale, A., Procedural and short-term follow-up outcomes of Amplatzer Amulet Occluder versus Watchman FLX Device: A Meta-Analysis, Heart Rhythm, February 2022, https://doi.org/10.1016/j.hrthm.2022.02.007