ALB and atrial fibrillation: In the 8 phenogroups, key variables included LA and LV size and LVEF under echocardiographic features; age, sex, history of atrial fibrillation, chronic kidney disease, implantable cardioverter-defibrillator implantation, and degree of frailty under patient demographics; and N-terminal pro-B-type natriuretic peptide levels, hemoglobin levels, D-dimer, estimated glomerular filtration rate, albumin levels, and free triiodothyronine under laboratory features (Figure 1).