title: The impact of renal dysfunction on outcomes in the ExTRACT-TIMI 25 trial.
abstract: OBJECTIVE
  The ExTRACT-TIMI 25 (Enoxaparin and Thrombolysis Reperfusion for Acute Myocardial Infarction Treatment-Thrombolysis In Myocardial Infarction 25) trial provided the opportunity to evaluate the impact of renal dysfunction on outcomes in patients with ST-segment elevation myocardial infarction (STEMI) and compare enoxaparin (ENOX) and unfractionated heparin (UFH).
  
  
  BACKGROUND
  It is unclear how renal dysfunction influences the balance between benefit and risk of antithrombotic therapy.
  
  
  METHODS
  In the ExTRACT-TIMI 25 trial, 20,479 patients were randomized to UFH or ENOX. A reduced ENOX dose was administered to patients age > or =75 years and those with an estimated creatinine clearance (CrCl) <30 ml/min.
  
  
  RESULTS
  A powerful relationship was observed between the severity of renal dysfunction (per 10 ml/min decrement in CrCl) and death, stroke, intracranial hemorrhage, and major and minor bleeding (p < 0.001 for each). There was a progressive increase in the treatment benefit with ENOX on death or nonfatal myocardial infarction (p < 0.01) with better renal function. Net clinical benefit (death, nonfatal MI, or nonfatal major bleeding) was significantly superior with ENOX (p < 0.001) for patients with a CrCl >60 ml/min (79.1% of the study population). Major bleeding and intracranial hemorrhage did not differ for patients with preserved renal function (CrCl >90 ml/min), but in those with renal dysfunction there was a progressively greater increase in the risk of major and minor bleeding with ENOX.
  
  
  CONCLUSIONS
  Enoxaparin was superior to UFH for the majority of subjects. With more severe renal dysfunction, the net clinical benefit between ENOX and UFH did not differ, despite the rise in adverse events in both treatment groups. Future studies should take renal dysfunction into account when assessing antithrombotic regimens.
authors.affiliation: University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Keith A A
authors.initials: KA
authors.lastname: Fox
authors.forename: Elliott M
authors.initials: EM
authors.lastname: Antman
authors.forename: Gilles
authors.initials: G
authors.lastname: Montalescot
authors.forename: Stefan
authors.initials: S
authors.lastname: Agewall
authors.forename: Bhupathi
authors.initials: B
authors.lastname: SomaRaju
authors.forename: Freek W A
authors.initials: FW
authors.lastname: Verheugt
authors.forename: Jose
authors.initials: J
authors.lastname: Lopez-Sendon
authors.forename: Hanoch
authors.initials: H
authors.lastname: Hod
authors.forename: Sabina A
authors.initials: SA
authors.lastname: Murphy
authors.forename: Eugene
authors.initials: E
authors.lastname: Braunwald
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003404:Creatinine / Q000652:urine; D004311:Double-Blind Method; D017984:Enoxaparin / Q000627:therapeutic use*; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006493:Heparin / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000188:drug therapy*; D051437:Renal Insufficiency / Q000150:complications*; D015912:Thrombolytic Therapy
chemical_list: D017984:Enoxaparin; D005343:Fibrinolytic Agents; D006493:Heparin; D003404:Creatinine