title: Hemodynamic evaluation of coronary artery bypass graft lesions using fractional flow reserve.
abstract: BACKGROUND
  Coronary angiography is limited by its inability to assess the hemodynamic significance of a coronary artery stenosis. The assessment of the physiological significance of saphenous vein graft (SVG) lesions with a pressure wire to determine the fractional flow reserve (FFR) is lacking.
  
  
  METHODS
  FFR was determined in 10 SVG lesions of 10 males who had stress myocardial perfusion imaging (MPI) prior to referral for percutaneous coronary intervention for clinical indications.
  
  
  RESULTS
  All SVGs had a diameter stenosis (DS) > 50% and 30% had a DS > or = 70%. A significant FFR was present in 30% of patients. Ischemia along the territory of the SVG was present in 20% of patients. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FFR < 0.75 for the detection of ischemia on stress MPI were 50, 75, 33, 85, and 70%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FFR < 0.75 for detecting > or = 70% DS on angiography were 33, 71, 33, 71, and 60%, respectively. There was no significant correlation between FFR and % DS (R(2) = 0.1, P = 0.35).
  
  
  CONCLUSIONS
  The use of FFR to assess the physiological significance of SVG lesions is feasible and provides an acceptable specificity and negative predictive value compared to stress MPI.
authors.affiliation: Birmingham VA Medical Center, Birmingham, AL, USA. raed.aqel@va.gov
authors.forename: Raed
authors.initials: R
authors.lastname: Aqel
authors.forename: Gilbert J
authors.initials: GJ
authors.lastname: Zoghbi
authors.forename: Fadi
authors.initials: F
authors.lastname: Hage
authors.forename: Louis
authors.initials: L
authors.lastname: Dell'Italia
authors.forename: Ami E
authors.initials: AE
authors.lastname: Iskandrian
mesh_terms: D000368:Aged; D003251:Constriction, Pathologic; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D023921:Coronary Stenosis / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D005240:Feasibility Studies; D053805:Fractional Flow Reserve, Myocardial; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D055414:Myocardial Perfusion Imaging; D011237:Predictive Value of Tests; D012501:Saphenous Vein / Q000473:pathology / Q000503:physiopathology / Q000637:transplantation*; D012680:Sensitivity and Specificity; D016896:Treatment Outcome