title: Differences in baseline characteristics, practice patterns and clinical outcomes in contemporary coronary artery bypass grafting in the United States and Europe: insights from the SYNTAX randomized trial and registry.
abstract: OBJECTIVE
  To investigate the until now undefined extent of differences in baseline characteristics, practice patterns and clinical outcomes of patients undergoing coronary artery bypass grafting (CABG) for complex coronary artery disease in the USA versus Europe.
  
  
  METHODS
  The impact of geographic enrollment on clinical outcomes was explored using the as-treated population of 1510 patients with de novo left main and/or three-vessel disease who underwent CABG in either the SYNTAX randomized trial or registries, and who were followed up for 5 years.
  
  
  RESULTS
  There were 259 (17%) patients enrolled in the USA. Patients in the USA had more comorbidities. Off-pump procedures were more frequent in the USA (32 vs 13% in Europe; P < 0.001), and crystalloid cardioplegia was used less often (17 vs 38% in Europe; P < 0.001). In the USA, more grafts per patient were used (3.1 ± 0.8 vs 2.7 ± 0.7 in Europe; P < 0.001), with less complete arterial grafting (5 vs 18% in Europe; P < 0.001) but more complete revascularization (80 vs 66% in Europe; P < 0.001). At 5-year follow-up, patients treated in the USA versus Europe had comparable rates of major adverse cardiac and cerebrovascular events (MACCEs: 28.7 vs 24.3%, respectively; P = 0.11) and the composite safety endpoint of death, stroke and myocardial infarction (MI; 15.3 vs 17.5%, respectively; P = 0.43), but a significantly higher rate of repeat revascularization (15.0 vs 9.8%, respectively; P = 0.011) driven by repeat percutaneous coronary intervention (14.6 vs 9.2%; P = 0.005) and not repeat CABG (0.4 vs 0.8%; P = 0.48). Rates of graft occlusion were significantly higher in the USA versus Europe (8.7 vs 3.2%; P < 0.001). In multivariate analysis, enrollment in the USA was a non-significant predictor of MACCE [hazard ratio (HR) = 1.31, 95% confidence interval (95% CI) 1.00-1.73; P = 0.053], but independently predicted repeat revascularization (HR = 1.66, 95% CI 1.12-2.46; P = 0.011) and graft occlusion (HR = 2.65, 95% CI 1.52-4.62; P = 0.001). It was also a non-significant predictor of reduced rates of MI (HR = 0.38, 95% CI 0.14-1.06; P = 0.064). Differences between the USA and Europe were most pronounced among patients who underwent off-pump CABG.
  
  
  CONCLUSIONS
  Repeat revascularization rates following CABG in the USA versus Europe were increased at 5 years, particularly in off-pump patients. There was no significant difference in the rate of death, stroke and MI.
authors.affiliation: Department of Cardiothoracic Surgery, Erasmus University Medical Center, Rotterdam, Netherlands.
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Head
authors.affiliation: Department of Cardiothoracic Surgery, Erasmus University Medical Center, Rotterdam, Netherlands.
authors.forename: Catalina A
authors.initials: CA
authors.lastname: Parasca
authors.affiliation: The Heart Hospital, Baylor Health Care Systems, Plano, TX, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Mack
authors.affiliation: Department of Cardiac Surgery, Herzzentrum Universität Leipzig, Leipzig, Germany.
authors.forename: Friedrich W
authors.initials: FW
authors.lastname: Mohr
authors.affiliation: Department of Cardiology, Institut Cardiovasculaire Paris Sud, Massy, France.
authors.forename: Marie-Claude
authors.initials: MC
authors.lastname: Morice
authors.affiliation: Department of Cardiovascular Disease, Mayo Clinic, Rochester, MN, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Holmes
authors.affiliation: Department of Cardiology, NorthShore University Health System, Evanston, IL, USA.
authors.forename: Ted E
authors.initials: TE
authors.lastname: Feldman
authors.affiliation: Boston Scientific Corporation, Natick, MA, USA.
authors.forename: Keith D
authors.initials: KD
authors.lastname: Dawkins
authors.affiliation: Department of Cardiology, San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Colombo
authors.affiliation: Department of Cardiology, Erasmus University Medical Center, Rotterdam, Netherlands.
authors.forename: Patrick W
authors.initials: PW
authors.lastname: Serruys
authors.affiliation: Department of Cardiothoracic Surgery, Erasmus University Medical Center, Rotterdam, Netherlands a.kappetein@erasmusmc.nl.
authors.forename: A Pieter
authors.initials: AP
authors.lastname: Kappetein
mesh_terms: D000368:Aged; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000401:mortality / Q000706:statistics & numerical data; D005060:Europe / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012042:Registries; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology
keywords: Coronary artery bypass grafting; Country; Europe; Geographic; SYNTAX; USA