Abstract 207: VITAL-AF: A Pragmatic Trial Integrating Routine Screening for Atrial Fibrillation During Primary Care Visits
Authors: Ashburner Jeffrey M , Atlas Steven J , McManus David D , Chang Yuchiao , Trisini Lipsanopoulos Ana T , Borowsky Leila H , Guan Wyliena , He Wei , Ellinor Patrick T , Singer Daniel E , Lubitz Steven A 
Published: April 2019

Background:
Atrial fibrillation (AF) is a common age-related arrhythmia associated with increased risk of ischemic stroke. Novel technology may permit efficient and effective AF screening among undiagnosed, at-risk individuals to reduce ischemic stroke through use of guideline-indicated oral anticoagulants (OAC). We designed VITAL-AF (ClinicalTrials.gov NCT03515057) as a pragmatic cluster-randomized trial in a large primary care network in the United States, with the primary objective of assessing the benefit of population-based screening for AF in older patients using a single-lead ECG as part of routine care.

Methods:
VITAL-AF was designed to be generalizable, implementable, and pragmatic. VITAL-AF includes all patients ≥ 65 years of age attending an outpatient visit in a participating site with a physician or nurse practitioner, embeds screening as part of routine assessment of vital signs at each encounter, utilizes clinic medical assistants rather than research personnel to conduct screening, and assesses outcomes using electronic health record data. Practices were randomized to the screening intervention or control arm. Control practices continue with true usual care that may include pulse palpation and rhythm assessment based upon physician standard practice. Here we present historical data from the network about the size, visit patterns, and characteristics of the eligible population prior to trial enrollment starting July 31, 2018.

Results:
Overall, 142,291 patients were seen in network practices in the prior 3 years. There were 35,856 (25%) eligible patients ≥ 65 years of age seen in 16 participating study sites (hospital, community and health center clinics) including 4,704 (13%) patients with known AF. In 2017, 93% of eligible patients ≥ 65 years completed at least one primary care outpatient visit, with 67% completing multiple visits. This population has many risk factors for AF including: 41% ≥ 75 years of age, 43% male, 70% with hypertension, 19% with coronary artery disease, 18% with diabetes, and 8% with heart failure. Among those without prevalent AF on OAC, 93% had a CHA2DS2-VASc score ≥ 2 with 40% having a score ≥ 4. The trial is in progress and subject accrual is expected to be complete as of late fall 2019.

Conclusion:
VITAL-AF is a pragmatic, population-based trial of a screening program for undiagnosed AF in older at-risk patients within a primary care network. To emphasize generalizability, ease of implementation, and to facilitate screening uptake across a range of primary care clinics, VITAL-AF uses a single, age-based eligibility criterion. A small percentage of patients with low CHA2DS2-VASc score or with prevalent AF will be screened. Outcome assessment will evaluate rates of new AF detection and appropriate use of OACs among all patients ≥ 65 years of age seen in a participating clinic.