Three-Year Outcomes From the Amplatzer Amulet Left Atrial Appendage Occluder Randomised Controlled Trial (Amulet IDE)

The Amulet IDE trial is the largest randomised trial evaluating the safety and effectiveness of the Amulet LAA occluder compared with the Watchman 2.5 device through five years. This analysis reports three-year outcomes from the trial comparing the two devices. Medication regimen and key clinical outcomes were reported through three years including: 1) composite of ischaemic stroke or systemic embolism; 2) composite of all strokes, systemic embolism (SE), or cardiovascular (CV) death; 3) major bleeding; and 4) all-cause death and CV death. A total of 1,878 patients at 108 sites were randomised. A significantly higher percentage of patients were free of oral anticoagulation usage at three years with the Amulet occluder (96.2%) versus the Watchman device (92.5%) (p<0.01). Clinical outcomes were comparable for the composite of ischaemic stroke or SE (5.0% vs 4.6%, p=0.69), composite of all strokes, SE, or CV death (11.1% vs 12.7%, p=0.31), major bleeding (16.1% vs 14.7%, p=0.46), all-cause death (14.6% vs 17.9%, p=0.08), and CV death (6.6% vs 8.5%, p=0.14) for the Amulet occluder and the Watchman device, respectively. Through three years, device factors (device-related thrombus or peri-device leak ≥3 mm) preceded ischaemic stroke events and CV deaths more frequently in Watchman device compared with Amulet occluder patients. The Amulet occluder demonstrated continued safety and effectiveness through three years in a high-risk population compared to the Watchman device. Device factors more frequently preceded ischaemic stroke events and CV deaths in the Watchman device group compared to the Amulet occluder.