Relationship of the percentage of circulating endothelial progenitor cell to the severity of coronary artery disease

Previous study demonstrated that the percentage of circulating endothelial progenitor cells was reduced in patients with coronary artery disease. However, the relationship of the percentage of circulating endothelial progenitor cells to the severity of coronary artery disease has not been investigated. The percentages of circulating endothelial progenitor cells were measured in 78 consecutive patients with unstable angina, as well as in 32 healthy volunteers. Dual-stained cells expressing CD34 and vascular endothelial growth factor receptor-2 were judged to be endothelial progenitor cells and were analyzed using flow cytometry. On stepwise multiple linear regression analysis, the percentages of circulating endothelial progenitor cells were independently decreased in patients with unstable coronary artery disease compared with those in the healthy volunteers (P < 0.05). Among patients with unstable coronary artery disease, the percentage of patients with at least one occluded vessel was significantly higher in patients with multi-vessel disease than in patients with single-vessel disease (P < 0.04). On stepwise multiple linear regression analysis, the percentages of circulating endothelial progenitor cells were independently decreased in patients with multi-vessel coronary artery disease compared with those in patients with single-vessel coronary artery disease (P < 0.03). Among patients with unstable coronary artery disease, the percentage of circulating endothelial progenitor cells was significantly related to the severity of coronary artery disease.