Analysis Of Correlated Factors On Low NT-proBNP Levels In Acute Heart Failure

BackgroundPlasma amino-terminal pro-brain natriuretic peptide (NT-proBNP) is elevated in patients with acute heart failure (AHF). However low NT-proBNP levels were showed in selected patients with acute heart failure. We aim to investigate the correlated factors on low NT-proBNP levels among acute heart failure (AHF) patients in emergency department (ED).MethodsPatients admitted to hospital for AHF were studied. We analyzed various clinical variables of patients according to plasma NT-proBNP level. Moreover, comparison of NT-proBNP levels between ischemic and non-ischemic AHF and analysis of correlated factors was conducted.ResultsIn this study,154 acute heart failure patients met the study criteria (117 male, median 74 years old). The lowest NT-proBNP group was associated with more ischemic AHF patients, higher LVEF levels, lower NYHA class than other groups. The plasma NT-proBNP levels were lower in ischemic group than non-ischemic group (p< 0.01). Moreover, the NT-proBNP concentrations were lower in patients with normal LVEF values, lower NYHA class, without AF and with first heart failure than in patients with reduced LVEF values (p< 0.001), higher NYHA class (p< 0.001), with AF (p< 0.05) and previous heart failure (p< 0.05). Meanwhile, there was a positive correlation between the NT-proBNP levels and time from onset to ED.ConclusionsThe NT-proBNP levels were relatively low in patients during early phases of AHF hospitalization and increased with the time interval. In AHF patients with early phases, low NT-proBNP levels may infer an ischemic etiology especially in patients with nomal LVEF.