We examined 41 patients with ischemic heart disease (n=26) and dilated cardiomyopathy (DCM) (n=15). Control group comprised 15 practically healthy subjects. We found no substantial differences in the presence of CD34+CD133- and CD34+CD133-VEGFR-2+ cells in peripheral blood of patients with chronic heart failure (CHF) but noted lowering of level of CD34-CD133+VEGFR-2+ cells mainly in DCM group. Most significant factors determining lowering of number of circulating endothelial precursor cells (EPC) were age, level of low density lipoprotein cholesterol, and intima media thickness of common carotid arteries. We found lowering of colony forming ability of EPC in patients with CHF first of all in the group of patients with DCM. Abnormality of qualitative and quantitative composition of EPC can be considered as one of risk factors of endothelial dysfunction, pathological remodeling of cardiovascular system and CHF progression.