Background: Direct comparison of transcardiac increase in brain natriuretic peptide (BNP) and NT-pro-BNP has not been performed previously.
Aims: To evaluate the relation between BNP and NT-pro-BNP secretion, plasma levels and renal function.
Methods: We measured the plasma levels of BNP and NT-pro-BNP in the aortic root and coronary sinus in 326 consecutive patients with chronic heart failure (CHF). Patients were divided into two groups [group I: estimated glomerular filtration rate (eGFR)>or=60 mL/min and group II: eGFR<60 mL/min].
Results: The molar level of the transcardiac increase in NT-pro-BNP is lower than that of BNP. There were no differences in haemodynamics or the transcardiac gradient of BNP and NT-pro-BNP between group I and group II. The molar ratio of the plasma NT-pro-BNP to BNP was significantly higher in group II than in group I. By stepwise multivariate analyses, not only the left ventricular (LV) ejection fraction and LV end-diastolic pressure, but also eGFR, LV mass index (LVMI) and haemoglobin were independent predictors of plasma NT-pro-BNP and BNP.
Conclusion: The molar level of the transcardiac increase in NT-pro-BNP is lower than that of BNP; however, the influence of renal function on plasma NT-pro-BNP is greater than that on BNP.