Value of B-type natriuretic peptide for identifying significantly elevated pulmonary artery wedge pressure in patients treated for established chronic heart failure secondary to ischemic or idiopathic dilated cardiomyopathy

It has been suggested that plasma B-type natriuretic peptide (BNP) level may be used as a noninvasive biomarker of the adequacy of long-term heart failure therapy. The effect of contemporary therapy on the relation between BNP measured using modern commercially available assays and cardiac filling pressures has not been studied in detail, because most of the original studies predate these developments. The investigators sought to assess the diagnostic accuracy of BNP to identify significantly elevated pulmonary capillary wedge pressure (PCWP) in a group of patients with severe chronic heart failure on treatment. BNP correlated well with PCWP (r = 0.50, p <0.001), but the diagnostic accuracy of the test to identify patients with PCWP >15 mm Hg was only 74%, largely because of poor sensitivity or a large number of false-negative test results. Maximizing medical therapy irrespective of plasma BNP results remains the best approach to managing chronic heart failure.