title: Use of new-generation oral anticoagulant agents in patients receiving antiplatelet therapy after an acute coronary syndrome: systematic review and meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  Despite receipt of dual antiplatelet therapy, patients after an acute coronary syndrome (ACS) remain at significant risk for thrombotic events. The role of orally activated Xa antagonist (anti-Xa) and direct thrombin inhibitors is debated in this setting. Our study objective was to evaluate the efficacy and safety of new-generation oral anticoagulant agents compared with placebo in patients receiving antiplatelet therapy after an ACS.
  
  
  METHODS
  Electronic databases were searched to identify prospective randomized placebo-controlled clinical trials that evaluated the effects of anti-Xa or direct thrombin inhibitors in patients receiving antiplatelet therapy after an ACS. Efficacy measures included stent thrombosis, overall mortality, and a composite end point of major ischemic events, while thrombolysis in myocardial infarction-defined major bleeding events were used as a safety end point. The net clinical benefit was calculated as the sum of composite ischemic events and major bleeding events.
  
  
  RESULTS
  For the period January 1, 2000, through December 31, 2011, we identified 7 prospective randomized placebo-controlled clinical trials that met the study criteria, involving 31 286 patients. Based on the pooled results, the use of new-generation oral anticoagulant agents in patients receiving antiplatelet therapy after an ACS was associated with a dramatic increase in major bleeding events (odds ratio, 3.03; 95% CI, 2.20-4.16; P < .001). Significant but moderate reductions in the risk for stent thrombosis or composite ischemic events were observed, without a significant effect on overall mortality. For the net clinical benefit, treatment with new-generation oral anticoagulant agents provided no advantage over placebo (odds ratio, 0.98; 95% CI, 0.90-1.06; P = .57).
  
  
  CONCLUSIONS
  The use of anti-Xa or direct thrombin inhibitors is associated with a dramatic increase in major bleeding events, which might offset all ischemic benefits in patients receiving antiplatelet therapy after an ACS.
authors.affiliation: Department of Interventional Cardiology, Heart Institute, University of Pécs, Pécs, Hungary. andras.komocsi@aok.pte.hu
authors.forename: András
authors.initials: A
authors.lastname: Komócsi
authors.forename: András
authors.initials: A
authors.lastname: Vorobcsuk
authors.forename: Dániel
authors.initials: D
authors.lastname: Kehl
authors.forename: Dániel
authors.initials: D
authors.lastname: Aradi
mesh_terms: D054058:Acute Coronary Syndrome / Q000628:therapy*; D000925:Anticoagulants / Q000627:therapeutic use*; D003328:Coronary Thrombosis / Q000517:prevention & control*; D006801:Humans; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D016032:Randomized Controlled Trials as Topic
chemical_list: D000925:Anticoagulants; D010975:Platelet Aggregation Inhibitors