Meta-analysis of B-type natriuretic peptide in diagnosis of congestive heart failure in different clinical settings

Background: B-type natriuretic peptide (BNP) is a neurohormone released from the left ventricle in response to ventricular wall stress and pressure overload. BNP testing has been developed, and aids in identification of patients with suspected congestive heart failure (CHF). The objective of this study was to evaluate the role of BNP as a diagnostic marker of CHF, and determine its value in different clinical settings. Methods: A systematic review and meta-analysis of clinical studies regarding BNP and CHF was conducted. A comprehensive search of Medline, the Cochrane Library, and the reference sections of the primary studies was done. The methodologic quality of each study that met the inclusion criteria was assessed. The results of individual studies were described. The pooled sensitivity and specificity were calculated. Estimation of the diagnostic accuracy was done using meta-regression of the diagnostic odds ratio and summarized by a summary receiver-operating curve (S-ROC). Results: In total, 32 studies (n= 11054) met the inclusion criteria. The overall sensitivity and specificity at the optimum cutoff point are 81% (95% confidence interval: 0.76-0.86) and 86% ( 95% confidence interval: 0.81-0.89), respectively. The area under the S-ROC for all studies is 0.92.Nine papers included patients with dyspnea. The pooled negative likelihood ratio for this group was 0.12. Five studies included patients with chronic CHF and another seven studies included patients who were referred for echocardiography. The remaining studies were patients from the general population, patients with stable coronary artery disease, and patients referred for cardiac catheterization. Conclusion: BNP is a valuable tool in the diagnosis of CHF. It should be applied in the appropriate clinical setting. The strongest evidence of benefit for use of BNP is in patients presenting to the emergency room with dyspnea.