Aims Anaemia is prevalent in the chronic heart failure (CHF) population, but its cause is often unknown. The present study aims to investigate the relation between anaemia, renal perfusion, erythropoietin production, and fluid retention in CHF patients.

Methods and results We studied 97 patients with CHF, of which 15 had anaemia (Hb <13.0 g/dL in men and Hb <12.0 g/dL in women), without haematinic deficiencies. Glomerular filtration rate (GFR) and extracellular volume (ECV) were measured as the clearance and the distribution volume of constantly infused (125)I-iothalamate, respectively. Effective renal plasma flow (ERPF) was determined as the clearance of (131)I-hippuran. Anaemic CHF patients displayed significantly reduced GFR (P = 0.002), ERPF (P = 0.005) and EPO production (P = 0.001), and an elevated ECV (P = 0.015). Multivariable analysis demonstrated that lower GFR (P = 0.003), lower ERPF (P = 0.004), lower EPO production (P = 0.006), and a higher ECV (P = 0.001) were significant independent predictors of lower haemoglobin levels.

Conclusion Anaemia in CHF is not only independently associated with impaired renal perfusion and blunted EPO production, but to fluid retention as well.