title: β-blocker Therapy is Not Associated with Reductions in Angina or Cardiovascular Events After Coronary Artery Bypass Graft Surgery: Insights from the IMAGINE Trial.
abstract: OBJECTIVE
  To evaluate whether β-blockers were associated with a reduction in cardiovascular events or angina after Coronary Artery Bypass Graft (CABG) surgery, in otherwise stable low-risk patients during a mid-term follow-up.
  
  
  METHODS
  We performed a post-hoc analysis of the IMAGINE (Ischemia Management with Accupril post-bypass Graft via Inhibition of angiotensin coNverting Enzyme) trial, which tested the effect of Quinapril in 2553 hemodynamically stable patients with left ventricular ejection fraction (LVEF) >40 %, after scheduled CABG. The association between β-blocker therapy and the incidence of cardiovascular events (death, cardiac arrest, myocardial infarction, revascularizations, angina requiring hospitalization, stroke or hospitalization for heart failure) or angina that was documented to be due to underlying ischemia was tested with Cox regression and propensity adjusted analyses.
  
  
  RESULTS
  In total, 1709 patients (76.5 %) were using a β-blocker. Patients had excellent control of risk factors; with mean systolic blood pressure being 121 ± 14 mmHg, mean LDL cholesterol of 2.8 mmol/l, 59% of patients received statins and 92% of patients received antiplatelet therapy. During a median follow-up of 33 months, β-blocker therapy was not associated with a reduction in cardiovascular events (hazard ratio 0.97; 95 % confidence interval 0.74-1.27), documented angina (hazard ratio 0.85; 95 % confidence interval 0.61-1.19) or any of the individual components of the combined endpoint. There were no relevant interactions for demographics, comorbidities or surgical characteristics. Propensity matched and time-dependent analyses revealed similar results.
  
  
  CONCLUSIONS
  β-blocker therapy after CABG is not associated with reductions in angina or cardiovascular events in low-risk patients with preserved LVEF, and may not be systematically indicated in such patients.
authors.affiliation: Department of Cardiology, University Medical Center Groningen, Hanzeplein 1, P O Box 30001, 9700 RB, Groningen, The Netherlands, hg.booij@umcg.nl.
authors.forename: Harmen G
authors.initials: HG
authors.lastname: Booij
authors.forename: Kevin
authors.initials: K
authors.lastname: Damman
authors.forename: J Wayne
authors.initials: JW
authors.lastname: Warnica
authors.forename: Jean L
authors.initials: JL
authors.lastname: Rouleau
authors.forename: Wiek H
authors.initials: WH
authors.lastname: van Gilst
authors.forename: B Daan
authors.initials: BD
authors.lastname: Westenbrink
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000368:Aged; D000787:Angina Pectoris / Q000503:physiopathology* / Q000628:therapy; D001026:Coronary Artery Bypass / Q000401:mortality; D004311:Double-Blind Method; D005260:Female; D006323:Heart Arrest / Q000503:physiopathology* / Q000628:therapy; D006333:Heart Failure / Q000188:drug therapy / Q000401:mortality / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology* / Q000628:therapy; D000077583:Quinapril; D012307:Risk Factors; D020521:Stroke / Q000188:drug therapy / Q000503:physiopathology*; D044005:Tetrahydroisoquinolines / Q000627:therapeutic use
chemical_list: D000319:Adrenergic beta-Antagonists; D044005:Tetrahydroisoquinolines; D000077583:Quinapril