Regional cardiac expression and concentration of natriuretic peptides in patients with severe chronic heart failure

The purpose of this study was to examine the regional cardiac mRNA expressi on and concentration of brain natriuretic peptide (BNP) and atrial natriure tic peptide (ANP) in relation to the circulating peptide concentrations in patients with chronic heart failure (CHF). The myocardial mRNA levels and p eptide concentrations of BNP and ANP were analysed in seven different regio ns of the heart from patients undergoing cardiac transplantation. Autopsy s amples from individuals without known cardiovascular disease were used as c ontrols. The plasma levels of natriuretic peptides and their N-terminal pro peptides, Nt-proBNP and Nt-proANP, were measured in the CHF patients and he althy volunteers. In the autopsy specimens, the atrial regions appeared to contain the highest peptide levels for BNP as well as ANP, the atrioventric ular ratio being 12-262 and 72-637-fold, respectively. In the CHF patients there was a relative shift towards the ventricle for BNP, reducing the atri oventricular ratio to 6-16-fold. The circulating concentrations of BNP/Nt-p roBNP in the CHF patients correlated closely to the BNP mRNA expression in most myocardial regions including the left ventricle (r = 0.72, P < 0.001). For circulating concentrations of ANP/Nt-proANP, such correlation were lim ited to the left atrium free wail (r = 0.66. P < 0.002). Thus, of the two n atriuretic peptides, BNP/Nt-proBNP may be a better reflector of left ventri cular overload.