The findings that DPPIV catalytic activity, as well as its binding properties, are associated with increased sodium reabsorption [26,39,40], inflammation [41,42,43] and cardiac fibrosis [32,33,36,37,38] are consistent with the hypothesis that increased DPPIV activity plays a role in the pathophysiology of HF. The gene discussed is DPP4; the disease is hydrops fetalis.