NT-proBNP in monitoring treatment of patients with congestive heart failure

OBJECTIVE: The aim of this study was to assess the utility of plasma N-terminal proBrain Natriuretic Peptide (NT-proBNP) assay in monitoring the therapy of congestive heart failure patients. BACKGROUND: Treatment of congestive heart failure aims to improve left ventricular function by reducing the pressure and volume overload. The human heart secretes brain natriuretic peptide in response to increased intracardiac volume or pressure. Therefore the therapy of congestive heart failure could have an effect on the plasma natriuretic peptide level. METHODS: The study included 149 patients with heart failure admitted to the Al-Assad and Al-Mowasah Hospitals, Damascus, Syria, during a 19-month period from February 2004 to September 2005. The age of the patients was between 35-85 years (mean+/-SD: 57+/-13.5). The patients were clinically divided into 4 groups according to the New York Heart Association Classification. Plasma NT-proBNP levels were measured and echocardiography was performed in all patients. We repeated physical examination, echocardiography, the patient's history, and the NT-proBNP assay in 46 patients from different stages after 3 months of drug treatment. The monitored patients were divided into three subgroups according to the clinical state: (A) 21 patients who clinically improved; (B) 18 patients with no clinical improvement; (C) 7 patients who were clinically stable. Plasma NT-proBNP levels were measured by electrochemiluminescence immunoassay (Roche). Statistical analysis was carried out by T-distribution, and the difference was considered to be significant at P < 0.05. RESULTS: The plasma NT-proBNP levels significantly decreased (P < 0.001) in clinically improved patients after 3 months of treatment, and this was accompanied by improvement of the echocardiographic data and symptoms. In contrast, the plasma NT-proBNP levels increased in patients with no clinical improvement and a decrease in the ejection fraction after 3 months of therapy, but the difference was not statistically significant (P > 0.05). There was also no statistically significant difference (P>0.05) between the plasma NT-proBNP level at diagnosis and after 3 months of treatment in clinically stable patients. CONCLUSION: The plasma NT-proBNP levels alter in response to drug therapy and can be used in monitoring treated patients with congestive heart failure.