title: Diagnostic Yield of Triple-Rule-Out CT in an Emergency Setting.
abstract: OBJECTIVE
  The objective of the present study is to quantify the diagnostic yield of triple-rule-out (TRO) CT for the evaluation of acute chest pain in emergency department patients.
  
  
  METHODS
  All TRO CT studies performed at our institution from 2006 to 2015 were reviewed. Scans were performed on a 256-MDCT scanner, with the use of ECG gating and a biphasic contrast injection. Radiology reports were reviewed to identify diagnoses that could explain chest pain, including coronary and noncoronary diagnoses, and significant incidental findings that did not account for the patient's presentation. The total numbers of coronary and noncoronary diagnoses and incidental findings were calculated.
  
  
  RESULTS
  Four of 1196 total cases that were identified were excluded from the study because of inadequate image quality. A total of 970 patients (81.4%) had a negative study result without a significant coronary or noncoronary diagnosis. A total of 139 patients (11.7%) had significant coronary artery disease (50% stenosis or greater). One hundred six patients (8.9%) had a noncoronary diagnosis that could explain chest pain (p < 0.02), most commonly pulmonary embolism (28 patients [2.3%]), aortic aneurysm (24 patients [2.0%]), or pneumonia (20 patients [1.7%]). Thirty cases (27.3%) of pulmonary embolism and aortic pathologic findings would not have been detected with coronary CT angiography because of unopacified right-side circulation or limited z-axis coverage. A total of 528 incidental findings not considered to explain chest pain were noted in 418 patients (35.1%).
  
  
  CONCLUSIONS
  In 8.9% of patients, TRO CT detected a significant noncoronary diagnosis that could explain acute chest pain, including pathologic findings that would not be identified on dedicated coronary CT angiography.
authors.affiliation: 1 Both authors: Department of Radiology, Thomas Jefferson University, 132 S 10th St, Philadelphia, PA 19104.
authors.forename: Amelia M
authors.initials: AM
authors.lastname: Wnorowski
authors.affiliation: 1 Both authors: Department of Radiology, Thomas Jefferson University, 132 S 10th St, Philadelphia, PA 19104.
authors.forename: Ethan J
authors.initials: EJ
authors.lastname: Halpern
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography / Q000379:methods; D055424:Cardiac-Gated Imaging Techniques; D002318:Cardiovascular Diseases / Q000000981:diagnostic imaging; D002637:Chest Pain / Q000000981:diagnostic imaging*; D003287:Contrast Media; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media
keywords: acute chest pain; acute coronary syndrome; pulmonary embolism; triple-rule-out CT