The Amulet device (Abbott, Chicago, IL) for left atrial appendage occlusion (LAAO) has been studied previously to reduce the risk of atrial fibrillation-related stroke in patients with an appropriate rationale for seeking an alternative to anticoagulation. The manufacturer-sponsored CATALYST trial seeks to elevate Amulet to a first-line therapy. CATALYST will enroll 2650 subjects with CHA2DS2-VASc scores > 3 and without contraindications to anticoagulation at up to 150 sites. Subjects will be randomized 1:1 to left atrial appendage occlusion (LAAO) with the Amulet device or a direct oral anticoagulant (DOAC). Patients will be followed for 24 months for two co-primary outcomes: one, a composite of thromboembolic events and cardiovascular death, (non-inferiority) and the other, the rate of non-procedural bleeding (superiority). Boston Scientific is conducting a similar trial of the Watchman FLX device called CHAMPION-AF.

ClinicalTrials.gov Identifier:  NCT04226547