ABSTRACT
<p><b>OBJECTIVE</b>To explore if reduced number of circulating endothelial progenitor cells (EPCs) is a risk factor for patients with coronary slow flow (CSF).</p><p><b>METHODS</b>Thirty patients with CSF and 30 age and gender matched control subjects with normal coronary angiography were included in the study. Mononuclear cells were isolated from peripheral blood by Ficoll density gradient centrifugation and plated on fibronectin-coated culture dishes. EPCs were characterized as adherent cells double positive for DiI-AcLDL-uptake and lectin-binding by converted fluorescence microscope (×200).</p><p><b>RESULTS</b>Smoking, diabetes mellitus, hypertension and the levels of plasma lipoprotein profile were similar between the two groups (all P > 0.05). The number of EPCs was significantly lower in patients with CSF compared with control subjects (35.7 ± 5.9 vs.53.2 ± 5.9, P < 0.01). TIMI frame counts was correlated with circulating EPCs number (OR = 0.424, 95%CI 0.358 - 0.621, P < 0.01) and not associated with gender, age, smoking, diabetes mellitus, hypertension and the levels of plasma lipoprotein profile.</p><p><b>CONCLUSION</b>Decreased circulating EPCs is an independent risk factor for CSF.</p>