title: Reoperative coronary bypass surgery: effect of patent grafts and retrograde cardioplegia.
abstract: OBJECTIVE
  To determine the effects of patent or diseased aorta-coronary bypass grafts and retrograde cardioplegia on mortality during reoperative coronary bypass surgery.
  
  
  METHODS
  We conducted a retrospective review of prospectively gathered data, supplemented by systematic chart review, of all patients (n = 744) undergoing reoperative coronary bypass surgery at our institution between 1990 and 1997. Independent predictors of survival were determined by stepwise logistic regression analysis.
  
  
  RESULTS
  At least one patent or stenosed graft to the left anterior descending artery was present in 50% of patients, to the circumflex territory in 27% of patients, and to the right coronary artery territory in 33% of patients. The previous left anterior descending graft was a saphenous vein in 82% and a left internal thoracic artery in 18% of patients. In-hospital mortality occurred in 42 (5.6%) patients. Patent or diseased grafts of any coronary artery territory did not significantly increase the risk of mortality. Retrograde cardioplegia use increased in more recent years, was more frequent in patients with stenosed grafts, and was associated with improved survival. Independent predictors of mortality were as follows (with odds ratios and 95% confidence intervals in parentheses): failure to use retrograde cardioplegia (odds ratio 2.81; 1.28-6.20), New York Heart Association class (odds ratio 2.69; 1.25-5.81), peripheral vascular disease (odds ratio 2.60; 1.25-5.41), and left ventricular grade (2.07; 1.31-3.27).
  
  
  CONCLUSIONS
  In this series, patent or stenosed grafts were not associated with an increased risk of mortality during reoperative coronary bypass surgery, possibly because of increased use of retrograde cardioplegia in this patient group. We strongly recommend the routine use of retrograde cardioplegia during redo coronary bypass surgery.
authors.affiliation: Division of Cardiovascular Surgery, Toronto General Hospital, University Health Network, Ontario, Canada.
authors.forename: M A
authors.initials: MA
authors.lastname: Borger
authors.forename: V
authors.initials: V
authors.lastname: Rao
authors.forename: R D
authors.initials: RD
authors.lastname: Weisel
authors.forename: A A
authors.initials: AA
authors.lastname: Floh
authors.forename: G
authors.initials: G
authors.lastname: Cohen
authors.forename: C M
authors.initials: CM
authors.lastname: Feindel
authors.forename: H E
authors.initials: HE
authors.lastname: Scully
authors.forename: L L
authors.initials: LL
authors.lastname: Mickleborough
authors.forename: T M
authors.initials: TM
authors.lastname: Yau
mesh_terms: D001026:Coronary Artery Bypass / Q000379:methods* / Q000401:mortality; D003327:Coronary Disease / Q000401:mortality / Q000601:surgery*; D006083:Graft Occlusion, Vascular / Q000401:mortality / Q000601:surgery*; D006324:Heart Arrest, Induced / Q000401:mortality; D006801:Humans; D011379:Prognosis; D012008:Recurrence; D012086:Reoperation; D012189:Retrospective Studies; D015996:Survival Rate; D013895:Thoracic Arteries / Q000637:transplantation*