Background: B-type natriuretic peptide (BNP) has been largely validated in the etiologic diagnosis of acute dyspnea. Nevertheless, its reliability in the setting of a preserved left ventricular systolic function (ejection fraction >50%) has not been adequately established.
Objective: the study addressed the usefulness of BNP in the diagnosis of new-onset heart failure with a preserved systolic function in hypertensive patients hospitalized for acute dyspnea.
Methods: 59 consecutive hypertensive patients without history of heart failure and coronary disease were included. BNP was measured at presentation with the Triage system. Noninvasive estimation of left ventricular filling pressures by bedside tissue Doppler echocardiography at presentation was incorporated in the diagnostic criteria.
Results: the 30 patients with heart failure were not significantly different from the 29 patients with noncardiac cause of acute dyspnea regarding age, gender, body mass index and ejection fraction. Median levels of BNP were significantly higher in heart failure (447 [245-644] versus 87 [43-139] pg/mL). By multivariate logistic regression analysis, BNP (odds ratio of 44, [3.6-531], p=0.003) provided independent and incremental diagnostic information over the clinical score of Boston criteria (2.25, [1.3-3.9], p=0.0037). A BNP value of >142 pg/mL (area under the ROC curve of 0.89, p<0.0001) was 93 sensitive and 79% specific for the diagnosis of heart failure in this setting.
Conclusion: BNP is a reliable biomarker of new-onset heart failure with a preserved systolic function in hypertensive patients, in particular older, hospitalized for acute dyspnea and can be safely integrated in the diagnostic strategy.