title: Clinical outcomes following stent thrombosis occurring in-hospital versus out-of-hospital: results from the HORIZONS-AMI (Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction) trial.
abstract: OBJECTIVE
  The study sought to determine whether rapid access to medical care and reperfusion results in a better prognosis in patients with in-hospital compared with out-of-hospital stent thrombosis (ST) in patients with ST-segment elevation myocardial infarction (STEMI) in the HORIZONS-AMI (Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction) trial.
  
  
  BACKGROUND
  Whether the prognosis of in-hospital and out-of-hospital ST are similar is uncertain, with conflicting data reported from prior studies.
  
  
  METHODS
  A total of 3,602 STEMI patients undergoing primary percutaneous coronary intervention (PCI) were randomized to bivalirudin (n = 1,800) versus unfractionated heparin (UFH) plus a glycoprotein IIb/IIIa inhibitor (GPI) (UFH+GPI; n = 1,802). Stents were implanted in 3,202 patients, 156 (4.9%) of whom developed Academic Research Consortium definite/probable ST during 3-year follow-up. We investigated the 1-year clinical outcomes after ST in 54 patients with in-hospital ST compared with 102 patients with out-of-hospital ST.
  
  
  RESULTS
  One year after the ST event, patients with in-hospital compared with out-of-hospital ST had significantly greater mortality (27.8% vs. 10.8%, p < 0.01); most deaths in both groups occurred within 1 week of the ST event. Patients with in-hospital ST also had higher rates of major bleeding (21.2% vs. 6.0%, p < 0.01), but a lower rate of myocardial infarction (56.6% vs. 77.5%, p < 0.01). Subgroup analysis within both in-hospital and out-of-hospital ST groups indicated that subacute ST had the highest mortality. By multivariable analysis, 1-year mortality was significantly increased in patients with in-hospital compared with out-of-hospital ST (adjusted hazard ratio: 4.62, 95% confidence interval: 1.98 to 10.77, p < 0.01). Additional correlates of increased mortality after an ST event included diabetes and randomization to UFH+GPI (vs. bivalirudin).
  
  
  CONCLUSIONS
  Following primary PCI for STEMI, more than one-third of all ST events during 3-year follow-up occurred during the index hospital phase. Mortality and major bleeding were significantly higher after in-hospital ST compared with out-of-hospital ST. (Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction; NCT00433966).
authors.affiliation: Department of Cardiology, Mount Sinai Medical Center, New York, New York 10029, USA. george.dangas@mssm.edu
authors.forename: George D
authors.initials: GD
authors.lastname: Dangas
authors.forename: Bimmer E
authors.initials: BE
authors.lastname: Claessen
authors.forename: Roxana
authors.initials: R
authors.lastname: Mehran
authors.forename: Sorin
authors.initials: S
authors.lastname: Brener
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Brodie
authors.forename: Dariusz
authors.initials: D
authors.lastname: Dudek
authors.forename: Bernhard
authors.initials: B
authors.lastname: Witzenbichler
authors.forename: Jan Z
authors.initials: JZ
authors.lastname: Peruga
authors.forename: Giulio
authors.initials: G
authors.lastname: Guagliumi
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Moses
authors.forename: Alexandra J
authors.initials: AJ
authors.lastname: Lansky
authors.forename: Ke
authors.initials: K
authors.lastname: Xu
authors.forename: Gregg W
authors.initials: GW
authors.lastname: Stone
mesh_terms: D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006629:Hirudins; D017052:Hospital Mortality / Q000639:trends*; D006760:Hospitalization / Q000639:trends; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality* / Q000601:surgery*; D009204:Myocardial Revascularization / Q000009:adverse effects* / Q000379:methods; D010446:Peptide Fragments / Q000627:therapeutic use; D011994:Recombinant Proteins / Q000627:therapeutic use; D012189:Retrospective Studies; D015607:Stents / Q000009:adverse effects*; D013927:Thrombosis / Q000209:etiology / Q000401:mortality*; D016896:Treatment Outcome
chemical_list: D006629:Hirudins; D010446:Peptide Fragments; D011994:Recombinant Proteins; C074619:bivalirudin