title: Does stenosis severity of native vessels influence bypass graft patency? A prospective fractional flow reserve-guided study.
abstract: BACKGROUND
  After coronary bypass surgery, occlusion or narrowing of bypass grafts may occur over time. The present study prospectively evaluated the angiographic patency of bypass grafts after 1 year in relation to the preoperative angiographic and functionally severity of the coronary lesion assessed by fractional flow reserve measurement to test the hypothesis that grafting of less critical stenosis may be a risk factor for early dysfunction of the graft.
  
  
  METHODS
  The study comprised 164 patients eligible for coronary artery bypass surgery who were not suitable for percutaneous intervention and with at least one intermediate lesion. Fractional flow reserve was measured in all lesions to be grafted to establish if a lesion was functionally significant. The surgeon was blinded to the results of these measurements. One year after surgery, coronary angiography was performed to establish bypass graft patency.
  
  
  RESULTS
  At coronary angiography after 1 year, 8.9% of the bypass grafts on functionally significant lesions were occluded, and 21.4% of the bypass grafts on functionally nonsignificant lesions were occluded. There was no difference in angina class or repeat interventions between patients with or without occluded bypass grafts.
  
  
  CONCLUSIONS
  The patency of bypass grafts on functionally significant lesions is significantly higher than the patency of bypass grafts on nonsignificant lesions; however, this finding has no clinical relevance because patients with patent or occluded bypass grafts on nonsignificant lesions did not experience an excess of angina or repeat interventions.
authors.affiliation: Department of Cardiology, Catharina Hospital, Eindhoven, The Netherlands. bot.joost@wxs.nl
authors.forename: Cornelis J
authors.initials: CJ
authors.lastname: Botman
authors.forename: Jacques
authors.initials: J
authors.lastname: Schonberger
authors.forename: Sjaak
authors.initials: S
authors.lastname: Koolen
authors.forename: Olaf
authors.initials: O
authors.lastname: Penn
authors.forename: Hilde
authors.initials: H
authors.lastname: Botman
authors.forename: Nabil
authors.initials: N
authors.lastname: Dib
authors.forename: Eric
authors.initials: E
authors.lastname: Eeckhout
authors.forename: Nico
authors.initials: N
authors.lastname: Pijls
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure; D017023:Coronary Angiography; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D003326:Coronary Circulation; D023921:Coronary Stenosis / Q000601:surgery*; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors