RESUMO
PURPOSE: Rapid diagnosis of congestive heart failure (CHF) is important for prompt and appropriate treatment, but is often difficult. The B-type natriuretic peptide (BNP) has been described as a powerful diagnostic test for heart failure. The goal of this study was to determine the diagnostic cutoff values of BNP, to evaluate useful factors for the diagnosis of CHF, and to develope a diagnostic algorithm for CHF with acute dyspnea patients. METHODS: BNP levels were obtained in 721 patients presenting to the emergency medical center with acute dyspnea from January 2001 to December 2002. With the use of inclusion criteria, 305 patients were excluded. Blood samples were collected by venipuncture and were analyzed by using Triage BNP assay. Included patients underwent echocardiography to evaluate the left ventricular (LV) dysfunction. RESULTS: The mean BNP concentration was higher in patients with CHF (n=214) than in those with other diagnose (517.31+/-37.70 pg/mL vs 75.53+/-11.25 pg/mL, p<0.001). At a blood concentration of 100 pg/mL, BNP showed a sensitivity of 79 %, a specificity of 83 %, a positive predictive value of 83%, and a negative predictive value of 79%. CONCLUSION: The BNP measurement is a useful tool in the diagnosis of CHF in patients presenting with dyspnea. We propose a diagnostic algorithm for CHF based on the BNP assay.