Plasma brain natriuretic peptide and atrial natriuretic peptide concentrations correlate with left ventricular end‐diastolic pressure

The present study was designed to investigate whether brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) plasma concentrations correlate with left ventricular end-diastolic pressure (LVEDP), pulmonary capillary wedge pressure (PCWP), diastolic pulmonary arterial pressure (DPAP), right atrial pressure (RAP), or ejection fraction (EF). Plasma BNP and ANP levels were determined by commercial radioimmunoassays (Peninsula) after Sep Pak C18 extraction in blood samples withdrawn from the pulmonary artery and the left ventricle or from the left ventricle and the femoral vein in 85 patients undergoing diagnostic cardiac catheterization. Linear and nonlinear regression analysis and the paired sample t-test were applied to the data. Pulmonary arterial plasma BNP and ANP levels showed a close nonlinear correlation with LVEDP (BNP: r = 0.94, p < 0.001; ANP: r = 0.81, p < 0.001), a significant linear correlation with PCWP, DPAP, and RAP, and a significant negative correlation with EF. ANP concentrations decreased significantly from the pulmonary artery to the left ventricle and from the left ventricle to the femoral vein (p < 0.001). BNP levels also decreased significantly between the left ventricle and the femoral vein (p < 0.001), but there was no significant difference between pulmonary arterial and left ventricular BNP concentrations. BNP and ANP concentrations correlated significantly between pulmonary arterial and left ventricular blood samples (BNP: r = 0.99, ANP: r = 0.93, p < 0.001) and between left ventricular and peripheral blood samples (BNP: r = 0.99, ANP: r = 0.94, p < 0.001). The present data suggest that peripheral plasma BNP and ANP levels are useful non-invasive indices of cardiac performance.