title: Clinical utility of coronary CT angiography: coronary stenosis detection and prognosis in ambulatory patients.
abstract: BACKGROUND
  Multislice CT coronary angiography (MSCTA) accurately detects stenosis in patients undergoing coronary arteriography, but its accuracy in clinical outpatients is less certain. This study retrospectively analyzed MSCTA performance in a large outpatient cohort and examined 6-month clinical follow-up in those without invasive CA.
  
  
  METHODS
  Patients underwent MSCTA for clinical indications including symptoms or noninvasive results being either equivocal or suspected as incorrect by referring clinicians. Standard 16-slice CT scanner techniques were used, and results were analyzed on the basis of both patient and vessel. Patients were treated medically or sent to invasive angiography on the basis of MSCTA results and judgment of referring clinicians. All invasive angiograms were analyzed using quantitative coronary angiography. Six-month clinical follow-up was determined in patients without CA.
  
  
  RESULTS
  One thousand fifty-three consecutive patients were referred for MSCTA, resulting in 994 interpretable scans. Mean age was 58+/-13 years, 55% were male, 50% had prior noninvasive testing, and 90% had symptoms. Invasive angiography was performed in 160 patients, with significant stenoses present in 69%. MSCTA demonstrated 87% and 89% accuracy by patient- and vessel-based analysis, respectively, and was most accurate in the left main and right coronary arteries. Only two patients not referred for angiography had significant stenosis in those undergoing 6-month follow-up.
  
  
  CONCLUSIONS
  MSCTA accurately detects obstructive coronary stenosis in clinical patients with possible cardiac symptoms, and effectively triages them for invasive angiography. Negative results are highly accurate in ruling out obstructive disease. Six-month prognosis is excellent in patients without significant disease determined by MSCT.
authors.affiliation: Minneapolis Heart Institute and Foundation, Minneapolis, Minnesota 55407, USA.
authors.forename: John R
authors.initials: JR
authors.lastname: Lesser
authors.forename: Bjorn
authors.initials: B
authors.lastname: Flygenring
authors.forename: Thomas
authors.initials: T
authors.lastname: Knickelbine
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Hara
authors.forename: Jason
authors.initials: J
authors.lastname: Henry
authors.forename: Ayesha
authors.initials: A
authors.lastname: Kalil
authors.forename: Kimberly
authors.initials: K
authors.lastname: Pelak
authors.forename: Jana
authors.initials: J
authors.lastname: Lindberg
authors.forename: Jamie
authors.initials: J
authors.lastname: Pelzel
authors.forename: Robert S
authors.initials: RS
authors.lastname: Schwartz
mesh_terms: D000368:Aged; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010045:Outpatients; D011379:Prognosis; D012042:Registries; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed