Epo serum levels in patients with and without coronary heart disease are related to EPC number and function. In patients with coronary heart disease (n = 38), Epo serum levels significantly correlated with the number of EPCs in the EPC culture assay (A), the number of CD34⁺/KDR⁺ cells (B), the number of CD34⁺/CD133⁺ cells (C), and the migratory capacity of cultivated EPCs (D). In patients with ischemic cardiomyopathy (n = 9), the number of hematopoietic bone marrow stem and progenitor cells (E-F) was significantly associated with Epo serum levels.