title: Variations in practice and outcomes in patients undergoing primary percutaneous coronary intervention in the United States and Canada: insights from the Assessment of Pexelizumab in Acute Myocardial Infarction (APEX AMI) trial.
abstract: BACKGROUND
  Information on practice patterns and outcomes in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary interventions (PCIs) in Canada vs United States is limited.
  
  
  METHODS
  We evaluated differences in clinical and angiographic features, practice patterns, and outcomes between Canada and United States in 2,086 patients with ST-elevation myocardial infarction undergoing primary PCI in the APEX AMI trial.
  
  
  RESULTS
  Of 2,086 patients, 335 (19%) were enrolled in Canada. Compared with US patients, Canadians were older with lower body mass index and creatinine clearance and less likely to have history of hypertension, smoking, or prior revascularization. Baseline infarct artery patency was higher, and the use of intra-aortic balloon pump and drug-eluting stents was lower in Canadian patients. Median door-to-PCI time was significantly shorter among Canadian patients (0.9 hours [interquartile range 0.6-1.3] vs 1.2 hours [interquartile range 0.8-1.7]). Clinical outcomes at 90 days were lower among Canadian patients, including shock (2.7% vs 4.2%), heart failure (3.6% vs 5.6%), bleeding (3.6% vs 9.6%), and atrial (3.6% vs 7.4%) and ventricular (3.0% vs 6.4%) arrhythmias. However, 90-day mortality (2.7% vs 4.8%, adjusted hazard ratio 0.62, 95% CI 0.47-1.28) and composite of death, shock, or heart failure (6.8% vs 11.5%, adjusted hazard ratio 0.77, 95% CI 0.47-1.27) were similar in the 2 cohorts.
  
  
  CONCLUSIONS
  Compared with US patients, Canadian patients had shorter door-to-PCI time but similar 90-day outcomes. These data suggest an opportunity for US sites to examine and learn from the Canadian systems of processes of care and implement changes so as to improve the timeliness of primary PCI.
authors.affiliation: Duke Clinical Research Institute, Durham, NC 27715, USA. raj.mehta@dm.duke.edu
authors.forename: Rajendra H
authors.initials: RH
authors.lastname: Mehta
authors.forename: Padma
authors.initials: P
authors.lastname: Kaul
authors.forename: Renato D
authors.initials: RD
authors.lastname: Lopes
authors.forename: Manesh R
authors.initials: MR
authors.lastname: Patel
authors.forename: Yinggan
authors.initials: Y
authors.lastname: Zheng
authors.forename: Karen S
authors.initials: KS
authors.lastname: Pieper
authors.forename: Robert C
authors.initials: RC
authors.lastname: Welsh
authors.forename: Paul W
authors.initials: PW
authors.lastname: Armstrong
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Granger
mesh_terms: D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D015906:Angioplasty, Balloon, Coronary / Q000379:methods* / Q000401:mortality; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use*; D002170:Canada; D003131:Combined Modality Therapy; D016001:Confidence Intervals; D017023:Coronary Angiography / Q000379:methods; D004562:Electrocardiography / Q000379:methods; D004630:Emergencies; D005069:Evaluation Studies as Topic; D005260:Female; D005500:Follow-Up Studies; D017052:Hospital Mortality / Q000639:trends*; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000401:mortality* / Q000628:therapy*; D010818:Practice Patterns, Physicians'; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012737:Sex Factors; D057127:Single-Chain Antibodies / Q000627:therapeutic use*; D015607:Stents; D015996:Survival Rate; D016896:Treatment Outcome; D014481:United States
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D057127:Single-Chain Antibodies; C402724:pexelizumab