Dara Baker is a 2020–2021 Doximity Research Review Fellow. Nothing in this article is intended nor implied to constitute professional medical advice or endorsement. The views expressed in this article are those of the author and do not necessarily reflect the views/position of Doximity.
The first year following a diagnosis of AFib is a tenuous one. During this time, known as “early AFib,” patients remain at an increased risk of cardiovascular complications despite adequate anticoagulation and rate control, which constitutes the standard of care. Given the significant morbidity and mortality associated with the condition, the investigators of the EAST-AFNET 4 trial sought to compare rhythm control methods to the status quo. While previous trials comparing medical rate control to rhythm control demonstrated no superiority in patients with established AFib, this is the first trial to specifically examine patients with early AFib and to include targeted ablation as part of management. These findings may herald a new frontier in the guidelines for treating early AFib.
The trial enrolled 2,789 patients, all over 75 years old with a history of treatment for transient ischemic attack or stroke or with two other specified comorbidities (e.g., renal or heart failure). Patients were randomized to rhythm control or usual care in a 1:1 ratio. At the third interim data evaluation, when 75% of the events had occurred, the trial was stopped early for efficacy, indicating significant benefit in the findings. Compared to usual care, the rhythm control group experienced significantly fewer first primary outcomes (3.9 per 100 person-years versus 5.0 per 100 person-years), including cardiovascular-related death, stroke, or hospitalization for worsening heart failure or acute coronary syndrome. Moreover, the two groups remained similar in rates of hospital night stays, the second primary outcome, and primary safety outcomes such as all-cause mortality, stroke, or a unique serious adverse event.
The results suggest that rhythm control, including treatment with antiarrhythmics and cardiac ablation, is associated with fewer serious cardiovascular events than rate control in this population. While the trial was limited by its necessarily open design, in which researchers and participants knew which treatment was being administered, the blinded assessment of primary outcomes reduced bias, strengthening confidence in the results. These conclusions may alter guidelines for the management of early AFib.
Dara Baker is a fourth-year medical student at GW SMHS, returning from her yearlong fellowship at NIH as part of the Medical Research Scholars Program, 2019–2020. She is an aspiring physician-scientist, excited about research in stem cell-based medicine, immunology, small molecule regulatory pathways, and genetics.