B-type natriuretic peptide in heart failure: diagnostic, prognostic, and therapeutic use.

Chronic heart failure affects nearly 5 million people living in the United States, and the majority of economic burden is the result of hospitalizations for acute decompensated congestive heart failure. Patient history and symptom assessment, physical examination, and chest radiography remain the cornerstones of diagnosis and prognostic assessment. Evaluation of endogenous B-type natriuretic peptide (BNP) has emerged as a useful addition to standard methods for diagnosis and risk stratification of suspected congestive heart failure, and final diagnosis requires integration of BNP assays with traditional methods. BNP levels >500 pg/mL are more likely to be comfirmative of a primary diagnosis of heart failure and are also important predictors for long-term adverse prognosis; >100 pg/mL but <500 pg/mL suggests a reasonable likelihood for the diagnosis of heart failure but does require thoughtful exclusion of other potential confounders such as pulmonary disease resulting in right heart failure; and <100 indicates that heart failure is very unlikely. Positive physiological effects of BNP, including improvements in hemodynamics, suppression of neurohormonal activity, preservation of renal function, diuresis and natriuresis, and balanced arterial and venous dilatation have suggested that this peptide also may have therapeutic use in congestive heart failure. In clinical trials, treatment of patients with acute decompensated congestive heart failure with nesiritide, a recombinant form of human BNP, was shown to significantly reduce pulmonary capillary wedge pressure versus placebo plus standard care, as well as provide a significant improvement in dyspnea versus placebo. Diagnostic, prognostic, and therapeutic applications of BNP can be integrated easily with standard methods to provide physicians with a useful evaluation and treatment algorithm that may result in faster identification of patients likely to benefit from early therapy, including nesiritide, thereby leading to the potential for more favorable patient outcomes.