Chen ML, et al. - Researchers investigated whether the observed lower rates of clinically apparent atrial fibrillation (AF) among black individuals vs other racial groups in the US is a true finding or is simply a result of more undiagnosed AF cases. Including patients aged ≥66 years with at least 1 documented Current Procedural Terminology code for interrogation of an implantable pacemaker, cardioverter-defibrillator, or loop recorder and no documented history of AF, atrial flutter, or stroke before their first device interrogation, they performed this retrospective cohort study. They used inpatient and outpatient claims from 2009 to 2015 for a 5% nationally representative sample of Medicare beneficiaries. Findings revealed a reduced incidence of AF—in spite of a greater burden of vascular risk factors and a greater stroke risk—in black patients who were Medicare beneficiaries with implanted cardiac devices capable of detecting atrial rhythm.