Chew N, Ngiam JN, Tan YQB, et al. - Given that atrial fibrillation (AF) causes the loss of atrial booster pump function as well as portends poorer result in aortic valve stenosis (AS), however, its features and influence on medically treated AS continued to be under-recognized, so, researchers compared these patients with AF vs sinus rhythm. This analysis involved 347 consecutive patients with medically treated severe AS (aortic valve area < 1cm²) and preserved left ventricular ejection fraction (> 50%). Lower body mass index, larger left ventricular mass index, and left atrial volume index were detected in AF patients. Atrial fibrillation was identified to be related to higher death, admissions for congestive cardiac failure, and poorer composite results. Follow-up revealed similar incidence of stroke in both groups. In this study, AF was identified as a crucial comorbidity influencing a quarter of patients with medically treated severe AS. It was shown to be independently related to poorer clinical results and may therefore help in prognostication as well as in management.