title: Utility of a genomic-based, personalized medicine test in patients presenting with symptoms suggesting coronary artery disease.
abstract: OBJECTIVE
  Better methods are needed to assess patients presenting with symptoms suggestive of obstructive coronary artery disease (CAD). We hypothesized that the use of a gene expression score (GES) would lead to a change in the diagnostic evaluation.
  
  
  METHODS
  The Primary Care Providers Use of a Gene Expression Test in Coronary Artery Disease Diagnosis (IMPACT-PCP) trial (clinical trial identifier NCT01594411, clinicaltrials.gov) was a prospective study of stable, nonacute, nondiabetic patients presenting with chest pain and related symptoms at 4 primary care practices. All patients underwent GES testing, with clinicians documenting their planned diagnostic strategy both before and after GES. The GES was derived from a peripheral blood draw measuring expression of 23 genes and has been shown to have a 96% negative predictive value for excluding the diagnosis of obstructive CAD.
  
  
  RESULTS
  Of the 251 study patients, 140 were women (56%); the participants had a mean age of 56 years (standard deviation, 13.0) and a mean body mass index of 30 mg/kg(2) (standard deviation, 6.7). The mean GES was 16 (range, 1-38), and 127 patients (51%) had a low GES ([ltqeu]15). A change in the diagnostic testing pattern before and after GES testing was noted in 145 of 251 patients (58% observed vs. 10% predefined expected change; P < .001).
  
  
  CONCLUSIONS
  Incorporation of the GES into the diagnostic workup showed clinical utility above and beyond conventional clinical factors by optimizing the patient's diagnostic evaluation.
authors.affiliation: Johns Creek Primary Care, Suwanee, GA; Family Care Clinic, Bonham, TX; Carolina Family Healthcare, Weddington, NC; The Lipid Center, Baton Rouge, LA; CardioDx, Inc., Palo Alto, CA; and Vanderbilt University, Nashville, TN.
authors.forename: Lee
authors.initials: L
authors.lastname: Herman
authors.forename: James
authors.initials: J
authors.lastname: Froelich
authors.forename: Dino
authors.initials: D
authors.lastname: Kanelos
authors.forename: Robert
authors.initials: R
authors.lastname: St Amant
authors.forename: May
authors.initials: M
authors.lastname: Yau
authors.forename: Brian
authors.initials: B
authors.lastname: Rhees
authors.forename: Mark
authors.initials: M
authors.lastname: Monane
authors.forename: John
authors.initials: J
authors.lastname: McPherson
mesh_terms: D000328:Adult; D000368:Aged; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000235:genetics; D005260:Female; D005500:Follow-Up Studies; D020869:Gene Expression Profiling; D005819:Genetic Markers; D005820:Genetic Testing / Q000379:methods*; D023281:Genomics; D006801:Humans; D008297:Male; D008875:Middle Aged; D057285:Precision Medicine / Q000379:methods*; D011237:Predictive Value of Tests; D011446:Prospective Studies
chemical_list: D005819:Genetic Markers
keywords: Cardiovascular Abnormalities; Genetics; Medical Decision Making; Practice-based Research; Technology Assessment