Although there’s still ongoing debate on who should receive LAAO devices, new five year results from the Amulet IDE trial confirm that both Abbott’s Amulet occluder and Boston Scientific’s Watchman 2.5 are safe and effective in the long run.
- LAAO (left atrial appendage occlusion) devices help prevent stroke in patients with AFib by sealing off the left atrial appendage where blood clots can form.
- Devices like the Amulet and Watchman provide an alternative to anticoagulants for AFib stroke prevention in patients who cannot take blood thinners.
Amulet IDE set Abbott’s contender against Boston Scientific’s Watchman 2.5 (its three generation old model), randomizing 1.9k patients to receive either the Amulet or Watchman and found that both devices had similar five year clinical outcomes, although Amulet held an edge in a couple key categories.
- The Amulet and Watchman devices were nearly tied for the study’s composite rate of ischemic stroke or systemic embolism after five years (7.4% vs. 7.1%).
- Both devices also had a similar rate of major bleeding (20.1% for Amulet vs. 20.0% for Watchman), CV death (14.3% vs 15.4%), and all-cause death (28.7% vs 31.1%).
- However, Amulet beat the Watchman when it came to oral anticoagulation use, since more Amulet patients remained OAC free after five years (94% vs. 90.9%).
The results of Amulet IDE also suggest that patients who experienced stroke during the study faced less severe strokes with the Amulet (nondisabling = 38, disabling = 11, fatal = 11) than with the Watchman (nondisabling = 19, disabling = 22, fatal = 17).
While the jury is still out on which patients need LAAO, the study only included adults at a high risk of stroke or systemic embolism with a CHADS2 score ≥2 or CHA2DS2-VASc score ≥3.
The Takeaway
The five year results from the Amulet IDE trial confirm that whether it’s an Amulet or a Watchman, both LAAO devices are likely to do their jobs well, but we’ll probably need more studies to confirm whether Amulet truly has a stroke severity and OAC advantage.
