BACKGROUND: The goal of this study was to evaluate the utility of plasma N-terminal pro-brain natriuretic peptide for the diagnosis of heart failure in patients presenting with shortness of breath. METHODS AND RESULTS: We measured plasma levels of N-terminal pro-brain natriuretic peptide in 119 patients presenting with shortness of breath. The patients were divided into two groups based on the Framingham criteria and echocardiographic results--those with heart failure and those not in heart failure. Plasma levels of N-terminal pro-brain natriuretic peptide were compared in the two groups. The mean N-terminal pro-brain natriuretic peptide concentration in patients with heart failure (n=73) was higher than that in those not in heart failure (389+/-148 fmol/ml v. 142+/-54 fmol/ml, p<0.001). N-terminal pro-brain natriuretic peptide values increased significantly as the functional severity of heart failure increased (p<0.001). The mean N-terminal pro-brain natriuretic peptide levels were 261+/-34 fmol/ml for patients in New York Heart Association functional class I, 300+/-161 fmol/ml for patients in New York Heart Association functional class II, 427+/-103 fmol/ml for patients in New York Heart Association functional class III and 528+/-170 fmol/ml for patients in New York Heart Association functional class IV. Using a cut-off value of 200 fmol/ml, the sensitivity of N-terminal pro-brain natriuretic peptide was 97%, specificity was 89% and accuracy for differentiating heart failure from other causes of shortness of breath was 93%. CONCLUSIONS: Our results suggest that N-terminal pro-brain natriuretic peptide can be reliably used for the diagnosis of heart failure in an outpatient setting, and this will improve the ability of clinicians to differentiate patients with shortness of breath due to heart failure from those with other causes of shortness of breath.
BACKGROUND: The goal of this study was to evaluate the utility of plasma N-terminal pro-brain natriuretic peptide for the diagnosis of heart failure in patients presenting with shortness of breath. METHODS AND RESULTS: We measured plasma levels of N-terminal pro-brain natriuretic peptide in 119 patients presenting with shortness of breath. The patients were divided into two groups based on the Framingham criteria and echocardiographic results--those with heart failure and those not in heart failure. Plasma levels of N-terminal pro-brain natriuretic peptide were compared in the two groups. The mean N-terminal pro-brain natriuretic peptide concentration in patients with heart failure (n=73) was higher than that in those not in heart failure (389+/-148 fmol/ml v. 142+/-54 fmol/ml, p<0.001). N-terminal pro-brain natriuretic peptide values increased significantly as the functional severity of heart failure increased (p<0.001). The mean N-terminal pro-brain natriuretic peptide levels were 261+/-34 fmol/ml for patients in New York Heart Association functional class I, 300+/-161 fmol/ml for patients in New York Heart Association functional class II, 427+/-103 fmol/ml for patients in New York Heart Association functional class III and 528+/-170 fmol/ml for patients in New York Heart Association functional class IV. Using a cut-off value of 200 fmol/ml, the sensitivity of N-terminal pro-brain natriuretic peptide was 97%, specificity was 89% and accuracy for differentiating heart failure from other causes of shortness of breath was 93%. CONCLUSIONS: Our results suggest that N-terminal pro-brain natriuretic peptide can be reliably used for the diagnosis of heart failure in an outpatient setting, and this will improve the ability of clinicians to differentiate patients with shortness of breath due to heart failure from those with other causes of shortness of breath.