title: Reduced circulating endothelial progenitor cells in the coronary slow flow phenomenon.
abstract: BACKGROUND
  Endothelial progenitor cells (EPCs) are important for maintaining the normal function and structure of endothelial cells. We tested the hypothesis that patients with coronary slow flow (CSF) have reduced circulating EPCs that may contribute to the pathogenesis of the CSF phenomenon.
  
  
  METHODS
  Twenty patients with angiographically proven normal coronary flow (the control group; mean age=55.6±8.2 years) and 20 patients with angiographically proven CSF in any coronary artery (the patient group; mean age=56.6±9.7 years) were included in the study. The thrombolysis in myocardial infarction (TIMI) frame count technique was used to document the coronary flow rates for all of the patients. Ficoll density gradient centrifugation was used to isolate mononuclear cells from peripheral blood cells. An inverted fluorescence microscope and direct fluorescent antibody staining were used to identify EPCs.
  
  
  RESULTS
  The number of EPCs was significantly reduced in the CSF patient group compared with the control group (36.95±6.1 vs. 53.95±6.7 EPCs/×200 field, P<0.01). A multivariate stepwise regression showed a significant negative correlation between the mean TIMI frame counts and the numbers of EPCs (regression coefficient B=-0.65, P<0.01).
  
  
  CONCLUSIONS
  The number of EPCs was reduced and correlated negatively with the TIMI frame count in the CSF patients. Reduced EPCs may be associated with the pathophysiological process of CSF phenomenon.
authors.affiliation: Department of Cardiology, The Affiliated Hospital of Guilin Medical College, Guangxi, China. drquanzhongli@yahoo.com.cn
authors.forename: Quanzhong
authors.initials: Q
authors.lastname: Li
authors.forename: Jinjie
authors.initials: J
authors.lastname: Han
authors.forename: Hua
authors.initials: H
authors.lastname: Chen
authors.forename: Xinling
authors.initials: X
authors.lastname: Mo
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D002469:Cell Separation / Q000379:methods; D002478:Cells, Cultured; D002499:Centrifugation, Density Gradient; D002932:Cineangiography; D017023:Coronary Angiography; D003326:Coronary Circulation; D015536:Down-Regulation; D042783:Endothelial Cells / Q000473:pathology*; D005260:Female; D019085:Fluorescent Antibody Technique, Direct; D006801:Humans; D008297:Male; D008856:Microscopy, Fluorescence; D008875:Middle Aged; D015999:Multivariate Analysis; D054318:No-Reflow Phenomenon / Q000097:blood / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D012044:Regression Analysis; D013234:Stem Cells / Q000473:pathology*