BNP is a cardiac neurohormone secreted from the ventricles in response to ventricular volume expansion and pressure overload (Moe, 2006), whereby its increased presence in the blood is indicative of a higher risk of heart attack, heart failure or death (Lainchbury et al., 2009; Pfisterer et al., 2009; Porapakkham et al., 2010). Here, NPPB is linked to heart failure.