Raising Hemoglobin levels is not always an unmitigated belssing. Studies in dialysis patients showed an increased risk of complications when Hb is raised above HB of 10-22. Meta-analysis of reported randomized clincal trials(RCT)s conclude that normalization of hemoglobin with erythropoietin is harmful.
The connection between heart failure(HF) and Hb levels appears to exist but it is not certain that low Hb worsens heart failure. Three studies have looked at raising Hb in HF, one with transfusion and two with erythropietin and produced inconsistent results, with only one of them, by Mancini et al, a randomized study, but it was a small study.
Erythropoietin receptors are present in a variety of tissues, including the heart, and erythropoietin may have anti-inflammatory and antiapoptotic properties. Recently published studies have demonstrated that treatment with rHuEPO favorably attenuated ischemia-reperfusion injury in a mouse model. Whether these findings will have physiologic relevance in humans remains unknown, but they do suggest an additional potential mechanism for beneficial effects of erythropoietin treatment in human HF. On the other hand, higher Hb levels may increase the physiologic stress on the heart and increase hypertension and stroke. Several studies are ongoing . Clearly, routine adoption of erythropoietic agents to treat HF and cardiomyopathy is premature.
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