title: Long-Term Survival and Freedom From Reintervention After Off-Pump Coronary Artery Bypass Grafting: A Propensity-Matched Study.
abstract: BACKGROUND
  The long-term outcomes of off-pump coronary artery bypass grafting (CABG) are the subject of speculation. Our institution has >15 years of experience performing CABG both off-pump (OPCAB) and on cardiopulmonary bypass (CPB). Our null hypothesis was that there would be no difference in a long-term composite of death and revascularisation between the 2 methods.
  
  
  METHODS
  We performed a retrospective cohort study of all isolated CABG at our institution from 2001 to 2015. We used an intention-to-treat analysis, performing risk adjustment with adjustment for and matching to propensity score. In total, 13 226 patients had CABG: 5882 had OPCAB and 7344 had CPB, with a median follow-up of 6.2 years.
  
  
  RESULTS
  Of the 5882 OPCAB, 76 (1.3%) converted to CPB. One-, 5-, and 10-year survivals in each group were similar (OPCAB vs CPB: 96.7%, 87.9%, 72.1% vs 96.2%, 87.4%, 72.8%). No difference was found in long-term survival (adjusted hazards ratio [HR] 1.03; 95% confidence interval [CI]: 0.94-1.11 for OPCAB vs CPB; P=0.56) or freedom from death and reintervention (HR 0.98; 95% CI: 0.92-1.06 for OPCAB vs CPB; P=0.23). Patients receiving OPCAB had higher EuroSCOREs (median [quartiles]: 2.81 [1.53-5.57] vs 2.73 [1.51-5.22]; P=0.01), fewer grafts (mean±SD: 3.0±0.9 vs 3.3±0.9; P<0.001), but more total arterial grafting (45.9% vs 8.4%; P<0.001). OPCAB also had more trainee first operators (15.3% vs 12.5%), lower cardiac enzyme rise, shorter length of stay, and fewer complications (such as myocardial infarction).
  
  
  CONCLUSIONS
  OPCAB is associated with similar long-term outcomes to CABG performed on CPB in our institution. Our low conversion rate to CPB, while training junior surgeons, demonstrates that OPCAB can be taught safely. The number of grafts performed between the 2 approaches is clinically comparable, if statistically different, and appears to provide equal benefits to survival and freedom from reintervention as on-pump CABG.
authors: From the Department of Cardiothoracic Surgery, Liverpool Heart and Chest Hospital, United Kingdom (B.H.K., A.D.M.); MRC Population Health Research Unit, Clinical Trial Service Unit & Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, United Kingdom (M.V.H.); and Clinical Trial Service Unit & Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, United Kingdom (M.V.H.). drkirmani@gmail.com.
authors: Bilal H
authors: BH
authors: Kirmani
authors: From the Department of Cardiothoracic Surgery, Liverpool Heart and Chest Hospital, United Kingdom (B.H.K., A.D.M.); MRC Population Health Research Unit, Clinical Trial Service Unit & Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, United Kingdom (M.V.H.); and Clinical Trial Service Unit & Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, United Kingdom (M.V.H.).
authors: Michael V
authors: MV
authors: Holmes
authors: From the Department of Cardiothoracic Surgery, Liverpool Heart and Chest Hospital, United Kingdom (B.H.K., A.D.M.); MRC Population Health Research Unit, Clinical Trial Service Unit & Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, United Kingdom (M.V.H.); and Clinical Trial Service Unit & Epidemiological Studies Unit (CTSU), Nuffield Department of Population Health, University of Oxford, United Kingdom (M.V.H.).
authors: Andrew D
authors: AD
authors: Muir
mesh_terms: D047549:Coronary Artery Bypass, Off-Pump / Q000401:mortality*; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D015996:Survival Rate
keywords: cardiopulmonary bypass; coronary artery bypass graft; off-pump surgery; outcome