The Impact of CHA₂DS₂-VASc and HAS-BLED Scores on Clinical Outcomes in the Amplatzer Amulet Study

Objectives: The aim of this study was to evaluate the impact of CHA₂DS₂-VASc and HAS-BLED scores on ischemic and bleeding events of patients enrolled in the Amplatzer Amulet Observational Study.

Background: Baseline CHA₂DS₂-VASc and HAS-BLED scores have been validated in atrial fibrillation patients to guide about anticoagulation but not in patients treated by left atrial appendage occlusion (LAAO).

Methods: Subjects were stratified according to CHA₂DS₂-VASc and HAS-BLED scores. Clinical outcomes were collected through 2 years and adjudicated by an independent committee.

Results: Subjects were considered at low (n = 156), moderate (n = 715), and high (n = 215) risk for ischemic stroke, corresponding to CHA₂DS₂-VASc scores of <3, 3 to 5, and ≥6, respectively. The annual rates of ischemic stroke were 1.1%, 2.0%, and 3.5%, respectively. When compared with the predicted rate, LAAO reduced the risk of ischemic stroke by 56%, 69%, and 68%. Device-related thrombus occurred in 0.7%, 1.5%, and 3.0% of subjects at low, moderate, and high risk for ischemic stroke, respectively. The HAS-BLED score was ≤3 in 629 subjects and >3 in 456 subjects, respectively. Non-peri-procedural major bleeding was reduced by 11% and 9% compared with predicted rates in the low and high bleeding risk groups, respectively.

Conclusions: LAAO with the Amplatzer Amulet reduced the risk of ischemic stroke compared with the predicted rate, with a greater magnitude among patients at high thromboembolic risk without increasing the bleeding risk. (Amplatzer™Amulet™ Post-Market Study [Amulet™PMS]; NCT02447081).