Electronic health record-embedded decision support to reduce stroke risk in patients with atrial fibrillation - Study protocol.

Background: Atrial fibrillation (AF) is the most common significant cardiac rhythm disorder and is a powerful common risk factor for stroke. Randomized trials have demonstrated that anticoagulation can reduce the risk of stroke in patients with AF. Yet, there continues to be widespread underutilization of this therapy. To address this practice gap locally and improve efforts to reduce the risk of stroke for patients with AF in our health system, we have designed a study to implement and evaluate the effectiveness of an Atrial Fibrillation Decision Support Tool (AFDST) embedded within our electronic health record.

Methods: Our intervention is provider-facing and focused on decision support. The clinical setting is ambulatory patients being seen by primary care physicians. Patients include those with both incident and prevalent AF. This randomized, prospective trial will enroll 800 patients in our University of Cincinnati Health System who are currently receiving less than optimal anticoagulation therapy as determined by the AFDST. Patients will be randomized to one of two arms - 1) usual care, in which the AFDST is available for use; 2) addition of a best practice advisory (BPA) to the AFDST notifying the clinician that their patient stands to gain a significant benefit from a change in their current thromboprophylactic therapy.

Results: The primary outcome is effectiveness of the BPA measured by change to "appropriate thromboprophylaxis" based on the AFDST recommendation at 3 months post randomization. Secondary endpoints include Reach and Adoption, from the RE-AIM framework for implementation studies. Sample size is based upon an improvement from inappropriate to appropriate anticoagulation therapy estimated at 4% in the usual care arm and ≥10% in the experimental arm.

Conclusion: Our goal is to examine whether addition of a BPA to an AFDST focused on primary care physicians in an ambulatory care setting will improve "appropriate thromboprophylaxis" compared with usual care. Results will be examined at 3 months post randomization and at the end of the study to evaluate durability of changes. We expect to complete patient enrollment by the end of June 2022.

Trial Registration: Clinicaltrials.gov NCT04099485.