The use of erythropoiesis-stimulating agents (ESA), specifically recombinant human erythropoietin- epoetin-alfa and epoetin-beta and the analogue darbepoetin alfa, has been evidenced in improving anemia in chronic kidney disease and malignancies prompting exploration of their potential effects on the treatment of anemia due to heart failure [51]. This evidence concerns the gene EPO and anemia (phenotype).