This study aimed to evaluate the clinical applicability of the plasma copeptin level to assess heart failure with reduced left ventricular ejection fraction (HFrEF). One hundred thirty-one patients with HFrEF, 127 patients with heart failure with preserved left ventricular ejection fraction (HFpEF), and 119 healthy candidates were involved. The basic data and examination results of patients were collected. The heart function of the patients with HFrEF and HFpEF were graded on the basis of the criteria of New York Heart Association (NYHA) classification. The plasma copeptin and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were tested using enzyme-linked immunosorbent assays (ELISAs). The copeptin and NT-proBNP levels were higher in the HFrEF group than in the HFpEF group. The copeptin and NT-proBNP values increased as the NYHA grade increased in the patients with HFrEF. However, for the patients with HFpEF, the copeptin levels did not change markedly as the NYHA grade increased. The copeptin levels were positively correlated with the NT-proBNP levels in the patients with HFrEF; however, there was no correlation between the copeptin and NT-proBNP values in the patients with HFpEF. Copeptin is involved in the process of progression in patients with HFrEF and the copeptin values might be useful for HFrEF prediction and assessment in the clinic.
