title: Relative importance of patient, procedural and anatomic risk factors for early vein graft thrombosis after coronary artery bypass graft surgery.
abstract: OBJECTIVE
  The aim of the present study was to investigate the relative importance of a wide array of patient demographic, procedural, anatomic and perioperative variables as potential risk factors for early saphenous vein graft (SVG) thrombosis after coronary artery bypass graft (CABG) surgery.
  
  
  METHODS
  The patency of 611 SVGs in 291 patients operated on at four different hospitals enrolled in the Reduction in Graft Occlusion Rates (RIGOR) study was assessed six months after CABG surgery by multidetector computed tomography coronary angiography or clinically-indicated coronary angiography. The odds of graft occlusion versus patency were analyzed using multilevel multivariate logistic regression with clustering on patient.
  
  
  RESULTS
  SVG failure within six months of CABG surgery was predominantly an all-or-none phenomenon with 126 (20.1%) SVGs totally occluded, 485 (77.3%) widely patent and only 16 (2.5%) containing high-grade stenoses. Target vessel diameter ≤ 1.5 mm (adjusted OR 2.37, P=0.003) and female gender (adjusted OR 2.46, P=0.01) were strongly associated with early SVG occlusion. In a subgroup analysis of 354 SVGs in which intraoperative graft blood flow was measured, lower mean flow was also significantly associated with SVG occlusion when analyzed as a continuous variable (adjusted OR 0.984, P=0.006) though not when analyzed dichotomously, <40 mL/min versus ≥ 40 mL/min (adjusted OR 1.86, P=0.08).
  
  
  CONCLUSIONS
  Small target vessel diameter, female gender and low mean graft blood flow are significant risk factors for SVG thrombosis within six months of CABG surgery in patients on postoperative aspirin therapy. This information may be useful in guiding revascularization strategies in selected patients.
authors: Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors: R C
authors: RC
authors: McLean
authors: S M
authors: SM
authors: Nazarian
authors: T J
authors: TJ
authors: Gluckman
authors: S P
authors: SP
authors: Schulman
authors: D R
authors: DR
authors: Thiemann
authors: E P
authors: EP
authors: Shapiro
authors: J V
authors: JV
authors: Conte
authors: J B
authors: JB
authors: Thompson
authors: I
authors: I
authors: Shafique
authors: K W
authors: KW
authors: McNicholas
authors: T C
authors: TC
authors: Villines
authors: K M
authors: KM
authors: Laws
authors: J J
authors: JJ
authors: Rade
mesh_terms: D000368:Aged; D016009:Chi-Square Distribution; D017023:Coronary Angiography / Q000379:methods; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D003326:Coronary Circulation; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012039:Regional Blood Flow; D018570:Risk Assessment; D012307:Risk Factors; D012501:Saphenous Vein / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000637:transplantation*; D012737:Sex Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014481:United States; D014654:Vascular Patency; D020246:Venous Thrombosis / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology