Antithrombotic Therapy and Cardiovascular Outcomes After Transcatheter Aortic Valve Replacement in Patients With Atrial Fibrillation.

Objectives: The study sought to determine the patterns of antithrombotic therapy and association with clinical outcomes in patients with atrial fibrillation (AF) and CHA ₂ DS ₂ -VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65-74 years, sex category) score ≥2 following transcatheter aortic valve replacement (TAVR).
Background: The impact of antithrombotic regimens on clinical outcomes in patients with AF and severe aortic stenosis treated with TAVR is unknown.
Methods: In the randomized PARTNER II (Placement of Aortic Transcatheter Valve II) trial and associated registries, 1,621 patients with prior AF and CHA ₂ DS ₂ -VASc score ≥2 comprised the study cohort. Outcomes were analyzed according to antithrombotic therapy.
Results: During the 5-year enrollment period, 933 (57.6%) patients were discharged on oral anticoagulant therapy (OAC). Uninterrupted antiplatelet therapy (APT) for at least 6 months or until an endpoint event was used in 544 of 933 (58.3%) of patients on OAC and 77.5% of patients not on OAC. At 2 years, patients on OAC had a similar rate of stroke (6.6% vs. 5.6%; p = 0.53) and the composite outcome of death or stroke (29.7% vs. 31.8%; p = 0.33), compared with no OAC. OAC with APT was associated with a reduced rate of stroke (5.4% vs. 11.1%; p = 0.03) and death or stroke (29.7% vs. 40.1%; p = 0.01), compared with no OAC or APT. Following adjustment, OAC with APT and APT alone were both associated with reduced rates of stroke compared with no OAC or APT (hazard ratio for OAC+APT: 0.43, 95% confidence interval: 0.22 to 0.85; p = 0.015; hazard ratio for APT alone: 0.32, 95% confidence interval: 0.16 to 0.65; p = 0.002), while OAC alone was not.
Conclusions: Among patients with prior AF undergoing TAVR, antiplatelet with or without anticoagulant therapy was associated with a reduced risk of stroke at 2 years, implicating multifactorial stroke mechanisms in this population.
(Copyright © 2019 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)