Chronic heart failure leads to an expanded plasma volume and pseudoanaemia, but does not lead to a reduction in the body's red cell volume

Abstract

Aims: Chronic heart failure (CHF) is frequently associated with a decreased haemoglobin level, whereas the mechanism remains largely unknown. Methods and results: One hundred consecutive CHF patients without anaemia or renal dysfunction based on non-cardiac reasons were enrolled. We explored determinants of anaemia (as iron parameters, erythropoietin, hepcidin and kidney function) including red cell volume (RCV) (by a 51 Cr assay) as well as related markers and plasma volume. The influence of each factor on haemoglobin concentrations was determined in a multiple regression model. Mean haemoglobin concentrations were 11.7 ± 0.8 mg/dL in anaemic CHF patients and 14.4 ± 1.2 mg/dL in non-anaemic patients. Corrected reticulocytes were lower in anaemic patients (35.1 ± 15.7 vs. 50.3 ± 19.2 G/L, P = 0.001), but the RCV was not reduced (1659.3 ± 517.6 vs. 1826.4 ± 641.3 mL, P = 0.194). We found that plasma volumes were significantly higher in anaemic CHF patients (70.0 ± 2.4 vs. 65.0 ± 4.0%, P < 0.001). Plasma volume was the best predictor of haemoglobin concentrations in the regression model applied (B = -0.651, P < 0.001, R2 = 0.769). Conclusion: Haemodilution appears to be the most potent factor for the development of low haemoglobin levels in patients with CHF. Our data support an additional independent, but minor influence of iron deficiency on haemoglobin concentrations in CHF patients. © The Author 2008. All rights reserved.