title: Additional value of adenosine-stress dynamic CT myocardial perfusion imaging in the reclassification of severity of coronary artery stenosis at coronary CT angiography.
abstract: OBJECTIVE
  To assess the additional value of adenosine-stress dynamic computed tomography (CT) perfusion (ASDCTP) imaging compared with coronary CT angiography (CCTA) alone to detect significant coronary artery stenosis for each threshold of 50% and 70% diameter stenosis.
  
  
  METHODS
  The study included 34 patients (65 ± 11 years, 79% men) with suspected coronary artery diseases who underwent ASDCTP imaging using a 128-section dual-source CT (DSCT) and invasive coronary angiography (ICA). Two investigators classified coronary artery stenosis on CCTA as severe or not. If appropriate image quality could not be acquired due to artefacts, the segment was classified as a lesion with significant stenosis. After the interpretation of ASDCTP imaging, the degree of stenosis was reclassified. All parameters of diagnostic accuracy were calculated before and after ASDCTP analysis for detection of significant coronary artery stenosis with ICA as the reference standard.
  
  
  RESULTS
  The diagnostic accuracy parameters per vessel for the detection of ≥50% stenosis before and after ASDCTP analysis changed as follows: sensitivity, from 80% to 83%; specificity, from 83% to 98%; positive predictive value (PPV), from 87% to 98%; and negative predictive value (NPV), from 75% to 80%. The addition of ASDCTP resulted in reclassification from one class of stenosis severity to another in a significant number of vessels with threshold of 50% stenosis [net reclassification improvement (NRI), 0.176; p < 0.01]. Conversely, the addition of ASDCTP did not result in significant reclassification of stenosis severity in vessels with threshold of 70% stenosis (NRI, 0.034; p = 0.51).
  
  
  CONCLUSIONS
  ASDCTP imaging provides incremental value in the detection of significant coronary artery stenosis using a threshold of 50%.
authors.affiliation: Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; Cardiovascular Imaging Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: S M
authors.initials: SM
authors.lastname: Kim
authors.forename: J-H
authors.initials: JH
authors.lastname: Choi
authors.forename: S-A
authors.initials: SA
authors.lastname: Chang
authors.forename: Y H
authors.initials: YH
authors.lastname: Choe
mesh_terms: D000241:Adenosine; D000368:Aged; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000145:classification / Q000000981:diagnostic imaging* / Q000473:pathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D000241:Adenosine