title: Deficiency of Endothelial Progenitor Cells Associates with Graft Thrombosis in Patients Undergoing Endovascular Therapy of Dysfunctional Dialysis Grafts.
abstract: BACKGROUND
  The deficiency of endothelial progenitor cells has been demonstrated to be associated with cardiovascular events in patients undergoing dialysis. However, their correlation with dialysis graft outcomes remains unknown. The objective of this study was to investigate the relationship between circulating endothelial progenitor cells and dialysis graft outcomes.
  
  
  METHODS
  After excluding 14 patients with acute coronary syndrome, decompensated heart failure or graft thrombosis in the prior three months, a total of 120 patients undergoing dialysis who underwent endovascular therapy of dysfunctional dialysis grafts were prospectively enrolled. Blood was sampled from study subjects in the morning of a mid-week non-dialysis day. Surface makers of CD34, KDR, and CD133 were used in combination to determine the number of circulating endothelial progenitor cells. All participants were prospectively followed until June 2013.
  
  
  RESULTS
  The median follow-up duration was 13 months, within which 62 patients experienced at least one episode of graft thrombosis. Patients with graft thrombosis had lower CD34+KDR+cell counts compared with patients without graft thrombosis (median 4.5 vs. 8 per 105mononuclear cells, p = 0.02). Kaplan-Meier analysis demonstrated thrombosis-free survival was lower in the low CD34+KDR+cell count group (30%) than in the high CD34+KDR+cell count group (61%; p = 0.007). Univariate analysis showed diabetes, high sensitive C-reactive protein, lesion length and CD34+KDR+cell counts associated with graft thrombosis. Multivariate analyses confirmed an independent association between low CD34+KDR+cell counts and graft thrombosis (hazard ratio, 2.52; confidence interval, 1.43-4.44; p = 0.001).
  
  
  CONCLUSIONS
  Our study demonstrated an independent association between low circulating endothelial progenitor cell counts and dialysis graft thrombosis.
authors.affiliation: Cardiovascular Center, National Taiwan University Hospital, Hsinchu Branch, Hsinchu.
authors.forename: Tsung-Yan
authors.initials: TY
authors.lastname: Chen
authors.affiliation: Cardiovascular Center, National Taiwan University Hospital, Hsinchu Branch, Hsinchu.
authors.forename: Lin
authors.initials: L
authors.lastname: Lin
authors.affiliation: Cardiovascular Center, National Taiwan University Hospital, Hsinchu Branch, Hsinchu; ; College of Medicine, National Taiwan University.
authors.forename: Mu-Yang
authors.initials: MY
authors.lastname: Hsieh
authors.affiliation: Cardiovascular Center, National Taiwan University Hospital, Hsinchu Branch, Hsinchu.
authors.forename: Jui-Cheng
authors.initials: JC
authors.lastname: Kuo
authors.affiliation: Cardiovascular Center, National Taiwan University Hospital, Hsinchu Branch, Hsinchu.
authors.forename: Chia-Ling
authors.initials: CL
authors.lastname: Wang
authors.affiliation: Cardiovascular Center, National Taiwan University Hospital, Hsinchu Branch, Hsinchu.
authors.forename: Ren-Huei
authors.initials: RH
authors.lastname: Wang
authors.affiliation: Cardiovascular Center, National Taiwan University Hospital, Hsinchu Branch, Hsinchu; ; College of Medicine, National Taiwan University.
authors.forename: Chao-Lun
authors.initials: CL
authors.lastname: Lai
authors.affiliation: School of Medicine, National Yang-Ming University, Taipei.
authors.forename: Po-Hsun
authors.initials: PH
authors.lastname: Huang
authors.affiliation: Cardiovascular Center, National Taiwan University Hospital, Hsinchu Branch, Hsinchu; ; College of Medicine, National Taiwan University; ; School of Medicine, National Yang-Ming University, Taipei; ; National Tsing-Hua University, Institute of Biomedical Engineering, Hsinchu, Taiwan.
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Wu
keywords: Endothelial progenitor cell; Graft; Hemodialysis; Thrombosis