title: Disruption of graft endothelium correlates with early failure after off-pump coronary artery bypass surgery.
abstract: BACKGROUND
  Saphenous vein graft failure after coronary artery bypass surgery may be as high as 5% to 10% in the first postoperative week. We hypothesized that identifying damage sustained by saphenous vein endothelium before grafting predicts early graft attrition after off-pump coronary artery bypass graft surgery.
  
  
  METHODS
  Intraoperative graft flow, platelet function, and endothelial integrity were analyzed in 125 patients undergoing off-pump coronary artery bypass graft surgery. Endothelial integrity was assessed in an excess vein segment from each graft using immunohistochemistry (CD31 staining). Platelet function was monitored just before and immediately after revascularization and on postoperative days 1 and 3 using whole blood aggregometry, thrombelastography, and platelet activated clotting time. Platelet activation was monitored using flow cytometry. Intraoperative conduit blood flow, measured by transit time ultrasonography, was used to detect and rectify anastomotic problems. Early graft patency was determined on postoperative day 5 using gated multichannel computed tomography angiography.
  
  
  RESULTS
  In 106 patients undergoing postoperative computed tomography evaluation, 10 vein grafts in 10 patients were discovered to have developed early thrombosis, representing 4% (10 of 217) of all vein grafts. Endothelial integrity was 10.75% +/- 17.56% in 10 grafts that failed early compared with 51.45% +/- 36.29% in patent grafts (p = 0.04). Perioperative platelet function and graft flow did not differ significantly between the two groups.
  
  
  CONCLUSIONS
  Although endothelial disruption predicts early failure of bypass grafts, the importance of a hypercoaguable state and low graft flow as a cause of early graft thrombosis after off-pump coronary artery bypass graft surgery was not supported by our preliminary results. A means to assess, prevent, and treat intraoperative vein graft damage will likely improve early graft patency.
authors.affiliation: Division of Cardiac Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA.
authors.forename: Jeffrey V
authors.initials: JV
authors.lastname: Manchio
authors.forename: Junyan
authors.initials: J
authors.lastname: Gu
authors.forename: Linda
authors.initials: L
authors.lastname: Romar
authors.forename: James
authors.initials: J
authors.lastname: Brown
authors.forename: James
authors.initials: J
authors.lastname: Gammie
authors.forename: Richard N
authors.initials: RN
authors.lastname: Pierson
authors.forename: Bartley
authors.initials: B
authors.lastname: Griffith
authors.forename: Robert S
authors.initials: RS
authors.lastname: Poston
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use; D047549:Coronary Artery Bypass, Off-Pump / Q000379:methods*; D003324:Coronary Artery Disease / Q000601:surgery; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006493:Heparin / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D015539:Platelet Activation; D011183:Postoperative Complications; D012307:Risk Factors; D012501:Saphenous Vein / Q000473:pathology* / Q000637:transplantation*; D019851:Thrombophilia; D013927:Thrombosis / Q000209:etiology; D016896:Treatment Outcome; D014654:Vascular Patency
chemical_list: D000925:Anticoagulants; D006493:Heparin