title: Clinical benefit of adenosine as an adjunct to reperfusion in ST-elevation myocardial infarction patients: An updated meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  Adenosine administered as an adjunct to reperfusion can reduce coronary no-reflow and limit myocardial infarct (MI) size in ST-segment elevation myocardial infarction (STEMI) patients. Whether adjunctive adenosine therapy can improve clinical outcomes in reperfused STEMI patients is not clear and is investigated in this meta-analysis of 13 randomized controlled trials (RCTs).
  
  
  METHODS
  We performed an up-to-date search for all RCTs investigating adenosine as an adjunct to reperfusion in STEMI patients. We calculated pooled relative risks using a fixed-effect meta-analysis assessing the impact of adjunctive adenosine therapy on major clinical endpoint including all-cause mortality, non-fatal myocardial infarction, and heart failure. Surrogate markers of reperfusion were also analyzed.
  
  
  RESULTS
  13 RCTs (4273 STEMI patients) were identified and divided into 2 subgroups: intracoronary adenosine versus control (8 RCTs) and intravenous adenosine versus control (5 RCTs). In patients administered intracoronary adenosine, the incidence of heart failure was significantly lower (risk ratio [RR] 0.44 [95% CI 0.25-0.78], P=0.005) and the incidence of coronary no-reflow was reduced (RR for TIMI flow<3 postreperfusion 0.68 [95% CI 0.47-0.99], P=0.04). There was no difference in heart failure incidence in the intravenous adenosine group but most RCTs in this subgroup were from the thrombolysis era. There was no difference in non-fatal MI or all-cause mortality in both subgroups.
  
  
  CONCLUSIONS
  We find evidence of improved clinical outcome in terms of less heart failure in STEMI patients administered intracoronary adenosine as an adjunct to reperfusion. This finding will need to be confirmed in a large adequately powered prospective RCT.
authors.affiliation: The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, NIHR University College London Hospitals Biomedical Research Centre, University College London, Chenies Mews, London, WC1E 6HX, UK; The Heart Hospital, 16-18 Westmoreland Street, London W1G 8PH, UK.
authors.forename: Heerajnarain
authors.initials: H
authors.lastname: Bulluck
authors.affiliation: The Heart Hospital, 16-18 Westmoreland Street, London W1G 8PH, UK.
authors.forename: Alex
authors.initials: A
authors.lastname: Sirker
authors.affiliation: University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
authors.forename: Yoon K
authors.initials: YK
authors.lastname: Loke
authors.affiliation: Cardiology Department, Valld'Hebron Hospital, Universitat Autónomade Barcelona, Barcelona, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Garcia-Dorado
authors.affiliation: The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, NIHR University College London Hospitals Biomedical Research Centre, University College London, Chenies Mews, London, WC1E 6HX, UK; The Heart Hospital, 16-18 Westmoreland Street, London W1G 8PH, UK; Cardiovascular and Metabolic Disorders Program, Duke-NUS Graduate Medical School, Singapore, Singapore; National Heart Research Institute Singapore, National Heart Centre Singapore. Electronic address: d.hausenloy@ucl.ac.uk.
authors.forename: Derek J
authors.initials: DJ
authors.lastname: Hausenloy
mesh_terms: D000241:Adenosine / Q000008:administration & dosage*; D004562:Electrocardiography; D006801:Humans; D009203:Myocardial Infarction / Q000503:physiopathology / Q000628:therapy*; D015425:Myocardial Reperfusion / Q000379:methods*; D062645:Percutaneous Coronary Intervention / Q000379:methods*; D016032:Randomized Controlled Trials as Topic; D014665:Vasodilator Agents / Q000008:administration & dosage
chemical_list: D014665:Vasodilator Agents; D000241:Adenosine
keywords: Adenosine; Adjunctive therapy; Primary percutaneous coronary intervention; Reperfusion injury; ST-segment elevation myocardial infarction