Background: The main approach to preventing stroke in patients with atrial fibrillation (AF) is anticoagulation (AC), but only about 60% of at-risk individuals are on AC. Patient-facing electronic health record-based interventions have produced mixed results. Little is known about the impact of health portal-based messaging on AC use.

Objective: The purpose of this study was describe a protocol we will use to measure the association between AC use and patient portal message opening. We also will measure patient attitudes toward education materials housed on a professional society Web site.

Methods: We will send portal messages to patients aged ≥18 years with AF 1 week before an office/teleconference visit with a primary care or cardiology provider. The message will be customized for 3 groups of patients: those on AC; those at elevated risk but off AC; and those not currently at risk but may be at risk in the future. Within the message, we will embed a link to UpBeat.org, a Web site of the Heart Rhythm Society containing patient educational materials. We also will embed a link to a survey. Among other things, the survey will request patients to rate their attitude toward the Heart Rhythm Society Web pages. To measure the effectiveness of the intervention, we will track AC use and its association with message opening, adjusting for potential confounders.

Conclusion: If we detect an increase in AC use correlates with message opening, we will be well positioned to conduct a future comparative effectiveness trial. If patients rate the UpBeat.org materials highly, patients from other institutions also may benefit from receiving these materials.