[Brain natriuretic peptide (BNP) in coronary insufficiency: relationship with left ventricular filling and exercise tolerance].

Brain natriuretic peptide (BNP) is a recently discovered peptide, secreted by the atria and ventricles in response to parietal distension. It was recently proposed as a screening test for left ventricular failure. The authors assayed this peptide at rest in 37 patients with chronic heart failure due to left ventricular systolic dysfunction and another 20 patients with various diseases (respiratory failure, cirrhosis, heart transplantation, "diastolic" heart failure) but normal left ventricular systolic function. A significant increase compared to normal values was observed not only in the group of heart failure patients, but also in patients with all other diseases. BNP was significantly higher in NYHA class IV patients. The relationship between plasma BNP levels and ejection fraction was not significant. On the other hand, a good correlation was observed between BNP and left ventricular filling parameters evaluated by cardiac Doppler: E wave deceleration time (r = -0.53, p = 0.001), E/A ratio: r = 0.57 p = 0.005) or VO2 max (r = -0.55, p < 0.005).