title: Systematic review of the accuracy of dual-source cardiac CT for detection of arterial stenosis in difficult to image patient groups.
abstract: OBJECTIVE
  To assess the diagnostic performance of dual-source cardiac (DSC) computed tomography (CT) newer-generation CT instruments for identifying anatomically significant coronary artery disease (CAD) in patients who are difficult to image by using 64-section CT.
  
  
  METHODS
  A literature search comprised bibliographic databases (January 1, 2000, to March 22, 2011, with a pragmatic update on September 6, 2012), trial registries, and conference proceedings. Only studies using invasive coronary angiography as reference standard were included. Risk of bias was assessed (QUADAS-2). Results were stratified according to patient group on the basis of clinical characteristics. Summary estimates of sensitivity and specificity of DSC CT for detecting 50% or greater arterial stenosis were calculated by using a bivariate summary receiver operating characteristic or random-effects model.
  
  
  RESULTS
  Twenty-five studies reported accuracy of DSC CT for diagnosing CAD in difficult to image patients; in 22 studies, one of two CT units of the same manufacturer (Somatom Definition or Somatom Definition Flash) was used, and in the remaining three, a different CT unit of another manufacturer (Aquilion One) was used. The pooled, per-patient estimates of sensitivity were 97.7% (95% confidence interval [CI]: 88.0%, 99.9%) and 97.7% (95% CI: 93.2%, 99.3%) for patients with arrhythmias and high heart rates, respectively. The corresponding pooled estimates of specificity were 81.7% (95% CI: 71.6%, 89.4%) and 86.3% (95% CI: 80.2%, 90.7%), respectively. All data were acquired by using Somatom Definition. In two studies with Somatom and one study with Aquilion One, sensitivity estimates of 90% or greater were reported in patients with previous stent implantations; specificities were 81.7% and 89.5% for Somatom and 81.0% for Aquilion One. In patients with high coronary calcium scores, previous bypass grafts, or obesity, only per-segment or per-artery data were available. Sensitivity estimates remained high (>90% in all but one study), and specificities ranged from 79.1% to 100%. All data were acquired by using Somatom Definition.
  
  
  CONCLUSIONS
  DSC CT may be sufficiently accurate to diagnose clinically significant CAD in some or all difficult to image patients.
  
  
  BACKGROUND
  http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.13121136/-/DC1.
authors: Kleijnen Systematic Reviews Ltd, Unit 6, Escrick Business Park, Riccall Road, Escrick, York YO19 6FD, England.
authors: Marie E
authors: ME
authors: Westwood
authors: Heike D I
authors: HD
authors: Raatz
authors: Kate
authors: K
authors: Misso
authors: Laura
authors: L
authors: Burgers
authors: Ken
authors: K
authors: Redekop
authors: Stefan K
authors: SK
authors: Lhachimi
authors: Nigel
authors: N
authors: Armstrong
authors: Jos
authors: J
authors: Kleijnen
mesh_terms: D001145:Arrhythmias, Cardiac / Q000150:complications / Q000503:physiopathology; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D012372:ROC Curve; D012307:Risk Factors; D012680:Sensitivity and Specificity; D015607:Stents; D014057:Tomography, X-Ray Computed / Q000379:methods*