Shin SY, Han SJ, Kim JS, et al. – In this investigation involving patients who suffered atrial fibrillation (AF)-related stroke, researchers determined the proportion of “clinically low-risk” patients using a nongender CHA₂DS₂-VASc (ie, CHA₂DS₂-VA) score of 0 to 1. They also assessed markers related to stroke in “clinically low-risk” patients. Participants (n = 3,033) were recruited retrospectively from 9 institutes in Korea and included nonvalvular AF patients who experienced an embolic stroke. Comparison of AF patients with CHA₂DS₂-VA score of 0 to 1 at the time of stroke vs “clinically low-risk” AF patients without stroke was carried out. The presence of CHA₂DS₂-VA score of 0 to 1 was reported in 583 patients (19.2%). An independent link with stroke was demonstrated by age (≥ 60 years), N-terminal pro B-type natriuretic peptide (≥ 300 pg/mL), creatinine clearance (< 50 mL/min), and left atrial dimension (≥ 45 mm) in multivariate analysis. A c-index of 0.858 was generated by the combined application of these four factors to the “clinically low-risk” patients. Overall, the investigators’ findings offer a novel insight into how stroke risk differentiation among AF patients initially classified as “clinically low-risk” could be further improved via the additional use of markers.