Circulating Endothelial Progenitor Cells In Patients With Heart Failure With Preserved Versus Reduced Ejection Fraction

Background: Heart failure with preserved ejection fraction (HFpEF) is a common clinical entity, with a mechanism that appears to involve endothelial dysfunction of the cardiac micro-circulation. Endothelial progenitor cells (EPC) are bone marrow derived cells that are able to differentiate into functional endothelial cells and participate in endothelial surface repair.Objectives: To compare the level and function of EPCs in patients with HFpEF compared with heart failure with reduced ejection fraction (HFrEF) and control subjects.Methods: We enrolled 21 patients with HFpEF (LVEF >= 50%, age 74.5 +/- 9.9 years, 43% men, 48% diabetes), 20 patients with HFrEF (LVEF < 40%, age 70 +/- 11.5 years, 90% men, 60% diabetes), and 11 control subjects with cardiovascular risk factors (age 53.3 +/- 6.1 years, 90% men, 64% diabetes). Circulating EPC levels were evaluated by expression of vascular endothelial growth factor receptor-2 (VEGFR-2), CD34, and CD133 by flow-cytometry. EPCs colony forming units (CPUs) were quantified after 7 days in culture.Results: The proportion of cells that co-expressed VEGFR-2 and CD34 or VEGFR-2 and CD133 was similar among the HF-pEF and HFrEF groups, and significantly lower than in the controt group. The number of EPC-CFUs was also similar among the two heart failure groups and significantly lower than the control group.Conclusions: Patients with HFpEF, like HFrEF, have significant reduction in EPC level and function.