Abstract 12176: Oral Anticoagulant Therapy Following Single-Lead ECG Screening Among Older Patients With Atrial Fibrillation: The VITAL-AF Trial

Abstract

Introduction: A substantial proportion of patients with atrial fibrillation do not take oral anticoagulants (OAC). Point of care ECG testing at primary care visits may prompt reassessment of OAC eligibility in patients with AF. Methods: VITAL-AF (NCT035115057) was a cluster-randomized trial of AF screening using single-lead handheld electrocardiograms within 16 primary care practices affiliated with Massachusetts General Hospital. The goal of VITAL-AF was to screen for undiagnosed AF. For pragmatic reasons the trial included all individuals aged ≥ 65 years, including those with an established diagnosis of AF. We evaluated screening uptake among prevalent AF patients in the screening arm, OAC initiation among both screening and control patients with prevalent AF, and OAC initiation by screening result (adjusted for stroke/bleed risk factors compared to all patients not screened). OAC use was identified using electronic health record medication lists during the 1-year prior to and following a patient’s study index visit. Results: Prevalent AF was present in 2,250 patients (75% on OAC) in the screening arm and 2,343 patients (76% on OAC) in the control arm. 90% of patients in the screening arm were screened at least once during the study period (mean 2.4 times screened). 31.5% had a “Possible AF” and 17.2% had an “Unclassified” automated algorithm screening result during their first screening encounter (40.1% “Possible AF” and 27.4% “Unclassified” during any encounter). Overall, OAC initiation was similar among prevalent AF patients from the screening arm and control arm ( Table ). OAC initiation was higher among screened patients who had a “Possible AF” automated result (Adjusted Odds Ratio 1.14, 95% CI: 1.05-1.24). Conclusions: Point of care cardiac rhythm assessment was not associated with significant changes in the use of OAC in patients with a history of AF. However, screened patients not on OAC who had a positive single-lead ECG were more likely to initiate OAC.