title: Evaluation of coronary artery in-stent patency using 64-slice computed tomography.
abstract: BACKGROUND
  Surveillance conventional coronary angiography (CCA) is recommended after stent supported percutaneous coronary intervention due to the unpredictable occurrence of in-stent restenosis (ISR). We explored the ability of 64-slice computed tomography angiography (CTA) to detect ISR after stenting of the coronary artery and analyzed the factors influencing imaging quality.
  
  
  METHODS
  Forty-five consecutive patients (29 stents) were examined by both CCA and 64-slice CTA after percutaneous coronary intervention. We analyzed the correlation between the image quality and heart rate, diameter, position, and stent-strut thickness. Compared with the CCA, the sensitivity, specificity, positive predictive value, and negative predictive value of 64-slice CTA for the detection of ISR were calculated. Between the patent group and ISR group, different computed tomography attenuation values of the in-stent lumen and artery 5 mm proximal and distal to the stent were also analyzed.
  
  
  RESULTS
  All stents were clearly visualized. With regard to the differences in heart rate, stent position, stent diameter, and stent-strut thickness among the different image quality groups, the P values were 0.47, 0.60, 0.04, and <0.01, respectively. Compared with CCA, the sensitivity, specificity, positive predictive value, and negative predictive value of 64-slice CTA were 100, 95.2, 88.9, and 100%, respectively. Between patent and ISR groups, the P values for the differences in CTA attenuation values of the in-stent lumen and artery 5 mm distal to the stent were 0.007 and 0.04, respectively.
  
  
  CONCLUSIONS
  We found that 64-slice spiral CTA is a reliable noninvasive diagnostic method that can display the stent lumen clearly and is especially helpful for patient follow-up.
authors.affiliation: Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Zheng
authors.forename: Youyou
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects / Q000295:instrumentation*; D002681:China; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000628:therapy*; D023903:Coronary Restenosis / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011474:Prosthesis Design; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D015607:Stents; D013997:Time Factors; D036542:Tomography, Spiral Computed; D016896:Treatment Outcome; D014654:Vascular Patency