title: Characteristics of ST Elevation Myocardial Infarction Patients Who Do Not Undergo Percutaneous Coronary Intervention After Prehospital Cardiac Catheterization Laboratory Activation.
abstract: OBJECTIVE
  To assess the clinical and electrocardiographic characteristics of patients diagnosed with ST elevation myocardial infarction (STEMI) that are associated with an increased likelihood of not undergoing percutaneous coronary intervention (PCI) after prehospital Cardiac Catheterization Laboratory activation in a regional STEMI system.
  
  
  METHODS
  We performed a retrospective analysis of prehospital Cardiac Catheterization Laboratory activations in Mecklenburg County, North Carolina, between May 2008 and March 2011. Data were extracted from the prehospital patient record, the prehospital electrocardiogram, and the regional STEMI database. The independent variables of interest included objective patient characteristics as well as documented cardiac history and risk factors. Analysis was performed using descriptive statistics and logistic regression.
  
  
  RESULTS
  Two hundred thirty-one prehospital activations were included in the analysis. Five independent variables were found to be associated with an increased likelihood of not undergoing PCI: increasing age, bundle branch block, elevated heart rate, left ventricular hypertrophy, and non-white race. The variables with the most significance were any type of bundle branch block [adjusted odds ratios (AOR), 5.66; 95% confidence interval (CI), 1.91-16.76], left ventricular hypertrophy (AOR, 4.63; 95% CI, 2.03-10.53), and non-white race (AOR, 3.53; 95% CI, 1.76-7.08). Conversely, the only variable associated with a higher likelihood of undergoing PCI was the presence of arm pain (AOR, 2.94; 95% CI, 1.36-6.25).
  
  
  CONCLUSIONS
  Several of the above variables are expected electrocardiogram mimics; however, the decreased rate of PCI in non-white patients highlights an area for investigation and process improvement. This may guide the development of prehospital STEMI protocols, although avoiding false positive and inappropriate activations.
authors.affiliation: From the *Department of Emergency Medicine, Indiana University School of Medicine, Indianapolis, IN; †Mecklenburg Emergency Medical Services Agency, Charlotte, NC; and ‡Department of Emergency Medicine, Carolinas Medical Center, Charlotte, NC.
authors.forename: Paul I
authors.initials: PI
authors.lastname: Musey
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Studnek
authors.forename: Lee
authors.initials: L
authors.lastname: Garvey
mesh_terms: D001741:Black or African American; D000367:Age Factors; D000368:Aged; D002037:Bundle-Branch Block / Q000453:epidemiology; D006328:Cardiac Catheterization; D016507:Cardiology Service, Hospital; D015897:Comorbidity; D004562:Electrocardiography; D004632:Emergency Medical Services; D005260:Female; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology / Q000503:physiopathology / Q000601:surgery*; D009657:North Carolina; D016017:Odds Ratio; D062645:Percutaneous Coronary Intervention / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D013610:Tachycardia / Q000453:epidemiology; D044465:White People