title: Multidetector CT coronary angiography for patient triage to invasive coronary angiography: Performance and cost in ambulatory patients with equivocal or suspected inaccurate noninvasive stress tests.
abstract: BACKGROUND
  Multidetector-CT angiography (MDCTA) differs from noninvasive stress tests by directly imaging coronary anatomy. The utility of MDCTA for invasive triage is undefined however. We evaluated MDCTA triage to invasive coronary angiography in outpatients with indeterminate or suspected inaccurate stress tests, and estimated cost savings by MDCTA in this role.
  
  
  METHODS
  Consecutive MDCTA patients were retrospectively compared with noninvasive stress tests if performed within 6 months of MDCTA. Twelve-month clinical follow up was obtained for patients not undergoing invasive angiography, and cost using MDCTA for triage to invasive coronary angiography was calculated.
  
  
  RESULTS
  MDCTA was performed in 385 patients who had noninvasive stress testing. Stress tests include included treadmill (n = 37), stress echo (n = 178), and nuclear perfusion imaging (n = 170). Invasive angiography was performed in 57 (14.8%). MDCTA compared to CA showed positive and negative predictive values of 94%/100% respectively for lesions found by invasive QCA. Stress testing compared to MDCTA showed positive/negative predictive values of 100%/67% for treadmill exercise, 60%/54% for stress echo, and 59%/55% of nuclear perfusion examinations respectively. One year clinical follow up in 314 patients showed no coronary events in 98% (309) of patients. Triage to invasive angiography by MDCTA showed a 4-fold cost reduction.
  
  
  CONCLUSIONS
  MDCTA shows excellent performance as a triage for invasive angiography in patients with stress tests that are equivocal or thought inaccurate. A negative CTA confers good 12-month prognosis. Substantial cost savings may accrue using MDCTA in this triage role.
authors.affiliation: Minneapolis Heart Institute Foundation, USA.
authors.forename: Madhav
authors.initials: M
authors.lastname: Menon
authors.forename: John R
authors.initials: JR
authors.lastname: Lesser
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Hara
authors.forename: Richard
authors.initials: R
authors.lastname: Birkett
authors.forename: Thomas
authors.initials: T
authors.lastname: Knickelbine
authors.forename: Terry
authors.initials: T
authors.lastname: Longe
authors.forename: Bjorn
authors.initials: B
authors.lastname: Flygenring
authors.forename: Jason
authors.initials: J
authors.lastname: Henry
authors.forename: Robert
authors.initials: R
authors.lastname: Schwartz
mesh_terms: D000368:Aged; D000553:Ambulatory Care / Q000191:economics*; D017023:Coronary Angiography / Q000191:economics* / Q000379:methods; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000191:economics; D017046:Cost Savings; D025401:Echocardiography, Stress; D005080:Exercise Test; D005260:Female; D017721:Hospital Costs; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000191:economics*