NPPB and heart failure: Worsening renal function affects clearance of NT-proBNP greater than BNP (Weber M and Hamm C, 2006), however deFilippi et al. have recently shown that the diagnostic accuracies of BNP and NT-proBNP in detecting decompensated heart failure are similar in patients with or without renal failure and that NT-proBNP is superior to BNP in predicting mortality (deFilippi CR et al. 2007).