Comparative Analysis Between NTproBNP and BNP on the Prediction for Congestive Heart Failure

ABSTRACT

PURPOSE: The BNP (B-type natriuretic peptide) test is a widely used diagnostic tool to differentiate congestive heart failure (CHF) from other diseases in patients with acute dyspnea in the emergency department. However, limited data exist regarding the effects of the left ventricular ejection fraction (LVEF) on NT-proBNP and BNP levels in acute CHF. We compared NT-proBNP with BNP in relation to the LVEF and correlated these levels to the CHF severity. METHODS: We assessed 113 patients who underwent BNP testing and echocardiography (Echo) during April 2005 and 127 patients who underwent NT-proBNP testing and Echo during May 2005. There were minimal differences with regard to epidemiologic data, past histories, clinical symptoms, New York Heart Association (NYHA) classifications, and final diagnoses between the two groups. We compared the sensitivity between BNP and NT-(pro)BNP in the diagnosis of heart failure, the change in BNP levels according to severity of CHF, and the optimal cutoff values of BNP and NT-proBNP. RESULTS: NT-(pro)BNP (AUC 95% confidence interval 0.875 - 0.965) was found to be superior to BNP (AUC 95% CI 0.675 - 0.851) in predicting CHF, it trended to be statistically significant. The BNP value correlated both with the severity of CHF (classified by NYHA) and LVEF gradings. The cutoff values for BNP and NT-(pro)BNP were 129 pg/mL and 451 pg/mL respectively. CONCLUSION : NT-proBNP is a more powerful predictor of acute CHF in patients presenting to the emergency department with acute dyspnea. Furthermore, NT-(pro)BNP tests may be useful in diagnosing and evaluating the severity of CHF.