title: beta-blockers before percutaneous coronary intervention do not attenuate postprocedural creatine kinase isoenzyme rise.
abstract: BACKGROUND
  beta-blocker (BB) use reduces infarct size in spontaneously occurring nonreperfused infarcts but probably does not change infarct size in patients treated with reperfusion therapy. A recent observational study suggested that BB use concurrent with percutaneous coronary intervention (PCI) decreased the risk of creatine kinase (CK)-MB elevation. The cogency of such a conclusion is dependent on the ability to risk-adjust for the multiple differences in patients treated with and without BBs.
  
  
  RESULTS
  Using propensity score and multivariate regression analyses, 6200 consecutive patients were analyzed to assess the relationship between BB use before PCI and per protocol-measured CK and CK-MB rise. There were several highly significant (P<0.001) differences between patients with and without BB treatment (eg, age, prior infarction, unstable angina). Maximum CK and CK-MB levels were higher in patients taking BBs (CK median, 95 U [interquartile range: 61, 175]; CK-MB, 3 U [2, 5]) than in patients not taking BBs (CK, 91 U [60, 157]; CK-MB, 3 U [2, 4]) (P=0.011 and P=0.021 for CK and CK-MB, respectively). After adjustment for significant differences in baseline characteristics there was no difference in either maximum CK rise (P=0.21) or maximum CK-MB rise (P=0.99).
  
  
  CONCLUSIONS
  The results of this large observation study do not support the contention that BB use before PCI decreases myocardial injury.
authors.affiliation: Department of Cardiology, The Cleveland Clinic Foundation, Cleveland, Ohio, USA. elliss@ccf.org
authors.forename: S G
authors.initials: SG
authors.lastname: Ellis
authors.forename: S J
authors.initials: SJ
authors.lastname: Brener
authors.forename: A M
authors.initials: AM
authors.lastname: Lincoff
authors.forename: D J
authors.initials: DJ
authors.lastname: Moliterno
authors.forename: P L
authors.initials: PL
authors.lastname: Whitlow
authors.forename: J P
authors.initials: JP
authors.lastname: Schneider
authors.forename: E J
authors.initials: EJ
authors.lastname: Topol
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects; D015331:Cohort Studies; D003327:Coronary Disease / Q000097:blood / Q000201:enzymology* / Q000628:therapy; D003402:Creatine Kinase / Q000097:blood*; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000097:blood; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D015425:Myocardial Reperfusion; D011183:Postoperative Complications / Q000517:prevention & control*; D011300:Preoperative Care; D011446:Prospective Studies; D018570:Risk Assessment; D017211:Treatment Failure; D016896:Treatment Outcome
chemical_list: D000319:Adrenergic beta-Antagonists; D007527:Isoenzymes; D003402:Creatine Kinase