Elevated NT-ProBNP levels in patients with increased left ventricular filling pressure during exercise despite preserved systolic function

Background: The role of brain natriuretic peptides in the detection of mild forms of isolated diastolic dysfunction is still uncertain. We therefore investigated the plasma levels of the N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with heart failure symptoms during exercise, despite preserved systolic cardiac function. Methods and Results: Fifteen control subjects and 15 symptomatic patients with preserved left ventricular ejection fraction of >= 50%, near normal Doppler echocardiographic indices, and left and right heart catheter indices at rest but increased filling pressures during exercise were studied. Plasma NT-proBNP levels and surrogate parameters of diastolic function were determined simultaneously. The median NT-proBNP plasma level was elevated (median, 145.2 pg/mL [range, 69.7-273.4 pg/mL] vs 38.3 pg/mL [range, 22.1-64.7 pg/ml]; P <.0001) in patients with increased filling pressure during exercise and correlated strongly with the pulmonary capillary wedge pressure (r = 0.78; P <.001). Conclusion: NT-proBNP levels are increased in patients with increased filling pressures during exercise and useful for the detection of diastolic dysfunction in patients with exertional dyspnea.