Postapproval registry (EMERGE LAA) of the first 12,180 patients with attempted Amulet occluder implantation for left atrial appendage occlusion (LAAO) in nonvalvular atrial fibrillation, captured in the US NCDR LAAO Registry between August 2021 and December 2023. Implantation success was 96.0% — 88.9% in patients with prior failed LAAO attempt. Clinically relevant closure (peridevice leak ≤3 mm) at day 45 was 97.2%. The composite safety endpoint (death, ischaemic stroke, embolism, device-/procedure-related events) occurred in 0.9%. Major adverse events at day 45 decreased with operator experience (8.4% at <10 cases to 5.8% at ≥30; p<0.001). At 1 year: 1.6% all stroke, 6.3% major bleeding, 2.9% CV/unknown-cause death, 7.9% all-cause death. The real-world data confirm safety and effectiveness of the Amulet occluder and highlight the impact of the learning curve on procedural outcomes.
The Amulet occluder is indicated to reduce the risk for thrombus embolization from the left atrial appendage in patients with nonvalvular atrial fibrillation.
The aim of this analysis was to evaluate outcomes through 1 year with the Amulet occluder in the EMERGE LAA postapproval study.
Patients with commercial Amulet occluder implantation attempts between August 14, 2021, and December 15, 2023, and entered into the National Cardiovascular Data Registry LAAO (Left Atrial Appendage Occlusion) Registry were included. The safety endpoint composite included all-cause death, ischemic stroke, systemic embolism, and device- or procedure-related events requiring open cardiac surgery or endovascular intervention between device implantation and 7 days or hospital discharge (whichever was later). Major adverse events were also reported through 1 year and stratified by operator experience and prior LAAO attempt.
A total of 12,180 patients underwent attempted Amulet occluder implantation (median follow-up 1 year (Q1-Q3: 1-1 year). Implantation success was 96.0% (11,693 of 12,180) (88.9% [353 of 397] in patients with prior failed LAAO attempts) with clinically relevant closure (peridevice leak ≤3 mm) achieved in 97.2% of patients (4,293 of 4,418) at 45 days postprocedure. A safety endpoint composite event occurred in 0.9% of patients (112 of 12,180). Any major adverse event through 45 days decreased with increased operator experience (<10 cases, 8.4% [166 of 1,969]; 10-29 cases, 6.5% [274 of 4,224]; ≥30 cases, 5.8% [348 of 5,987]; P < 0.001). At 1 year, Kaplan-Meier event rates of 1.6% for all stroke (n = 143), 6.3% for major bleeding (n = 610), 2.9% for cardiovascular-related death or death of unknown cause (n = 257), and 7.9% for all-cause death (n = 693) were observed.
One-year outcomes from EMERGE LAA for the first 12,180 patients demonstrated the success, safety, and effectiveness of the Amulet occluder in the real-world setting. Short-term rates of safety events were acceptable and decreased with operator experience, and 1-year outcomes demonstrate a low incidence of thromboembolic events.
