Measuring plasma B-type natriuretic peptide in heart failure

Elevated plasma brain natriuretic (BNP) concentrations correlate with increased cardiac filling pressures. Therefore, increased BNP has been proposed as a marker for asymptomatic ventricular dysfunction, as an aid in the diagnosis of cardiac dyspnea, as an end point to assess the efficacy of heart failure therapy, and as a prognostic marker in heart failure. An understanding of the utility of BNP requires an appreciation of the sensitivity, specificity, and diagnostic accuracy of BNP in each of these clinical situations. At this time, there is strong evidence for the value of BNP in the evaluation of dyspnea of uncertain cause. Further population studies will need to be performed to refine the application of BNP to community cohorts and to determine its clinical value and cost-effectiveness as a screening tool in the early diagnosis of ventricular dysfunction. To make optimal use of BNP for the assessment of heart failure therapy and prognosis in individual patients, physicians will require additional information on the biological variability of BNP. Studies comparing the sensitivity, specificity, and predictive value of the available BNP and N-terminal pro-BNP assays need to be conducted in each of these clinical settings.