Correlations between plasma concentration of brain natriuretic peptide and cardiac function in patients with heart failure

Objective:To demonstrate the relations of the plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) concentration with the severity of heart failure, the underling heart disease and the left ventricular function in patients with heart failure.Method: ① Plasma ANP and BNP concentrations of patients with heart failure (n=75) and of normal controls (n=60) were measured with immunoradiometricassay immediately after admission. ② Hemodynamic parameters were measured with Swan Ganz catheter in 75 patients on the same time. ③ Left ventricular ejection fraction was measured with 99m Tc gated ventriculography.Result:① The plasma ANP and BNP concentrations of patients were significantly higher than those of normal controls (P 0.01 ). They also increased according to the severity of heart failure classified by Forrester′s classification. The plasma ANP and BNP concentrations also had a significant positive and negative correlations with PCWP(r= 0.64 , P 0.01 ) and CI (r= -0.76 , P 0.01 ) respectively. In spite of same degree of CI, PCWP, LVEF and plasma level of ANP, the plasma BNP level was significantly higher in MI group than those in VHD and DCM group (P 0.01 ). The plasma BNP concentration had a significant correlation (r= -0.78 , P 0.01 ) with left ventricular ejection fraction.Conclusion:The plasma levels of ANP and BNP increase significantly according to the severity of heart failure classified by Forrester′s classification. The plasma BNP concentration is elevated more markedly in heart failure patients caused by myocardial infarction. The plasma BNP concentration may be a biochemical parameter for evaluating the left ventricular function.