Patients with LVEF >40%, elevated N-terminal pro B-typenatriuretic peptide (NT-proBNP) concentrations (i.e., >300 pg/mL in patients without and >900 pg/mL in patients with atrial fibrillation) along with evidence of structural changes in the heart or documented history of heart failure hospitalization. NYHA II-IV. Here, NPPB is linked to atrial fibrillation.