title: ST-segment recovery and outcome after primary percutaneous coronary intervention for ST-elevation myocardial infarction: insights from the Assessment of Pexelizumab in Acute Myocardial Infarction (APEX-AMI) trial.
abstract: BACKGROUND
  Primary percutaneous coronary angioplasty is an effective and widely adopted treatment for acute myocardial infarction. A simple method of determining prognosis after primary percutaneous coronary intervention (PCI) would facilitate appropriate care and expedite hospital discharge. Thus, we determined the prognostic importance of various measures of ST-segment-elevation recovery after primary PCI in a large, contemporary cohort of patients with ST-elevation myocardial infarction.
  
  
  RESULTS
  We analyzed ECG data describing the magnitude and extent of ST-segment elevation and deviation before and early after (ie, 30 minutes) primary PCI in the study cohort of 4866 subjects with electrocardiographically high-risk ST-elevation myocardial infarction enrolled in the Assessment of PEXelizumab in Acute Myocardial Infarction (APEX-AMI) trial. Associations among 6 methods for calculating ST-segment recovery, biomarker estimates of infarct size (ie, peak creatine kinase, creatine kinase-MB, and troponin I and T), and prespecified clinical outcomes (ie, rates of 90-day death and 90-day death, heart failure, or shock) were examined. All ST-segment-recovery methods provided strong prognostic information regarding clinical outcomes. A simple ST-segment-recovery method of residual ST-segment elevation measurement in the most affected lead on the post-PCI ECG performed as well as complex methods that required comparison of pre- and post-PCI ECGs or calculation of summed ST-segment deviation in multiple leads (ie, worst-lead residual ST elevation: adjusted hazard ratio for 90-day death rate [reference <1 mm]: 1 to <2 mm, 1.23 [95% CI 0.74 to 2.03]; > or =2 mm, 2.22 [95% CI 1.35 to 3.65], corrected c-index=0.832; 90-day death/congestive heart failure/shock [reference <1 mm]: 1 to <2 mm, 1.55 [95% CI 1.06 to 2.26]; > or =2 mm, 2.33 [95% CI 1.59 to 3.41], corrected c-index=0.802). Biomarker estimates of infarct size declined in association with enhanced ST-segment recovery.
  
  
  CONCLUSIONS
  An ECG performed early after primary PCI is a simple, widely available, inexpensive, and powerful prognostic tool applicable to patients with ST-elevation myocardial infarction.
authors.affiliation: Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Christopher E
authors.initials: CE
authors.lastname: Buller
authors.forename: Yuling
authors.initials: Y
authors.lastname: Fu
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Mahaffey
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Todaro
authors.forename: Peter
authors.initials: P
authors.lastname: Adams
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Westerhout
authors.forename: Harvey D
authors.initials: HD
authors.lastname: White
authors.forename: Arnoud W J
authors.initials: AW
authors.lastname: van 't Hof
authors.forename: Frans J
authors.initials: FJ
authors.lastname: Van de Werf
authors.forename: Galen S
authors.initials: GS
authors.lastname: Wagner
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Granger
authors.forename: Paul W
authors.initials: PW
authors.lastname: Armstrong
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000401:mortality*; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D015331:Cohort Studies; D003131:Combined Modality Therapy; D004562:Electrocardiography; D005260:Female; D006333:Heart Failure / Q000401:mortality; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000175:diagnosis / Q000401:mortality / Q000628:therapy; D011237:Predictive Value of Tests; D011379:Prognosis; D020127:Recovery of Function; D012770:Shock, Cardiogenic / Q000401:mortality; D057127:Single-Chain Antibodies; D016896:Treatment Outcome
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D057127:Single-Chain Antibodies; C402724:pexelizumab