title: Assessment of coronary artery stent patency by electron-beam CT.
abstract: Following coronary angioplasty and stent implantation, restenosis remains common and its outcome difficult to predict. We set out to determine the diagnostic accuracy of electron-beam computed tomography (EBCT) for the non-invasive detection of stent obstruction. In a prospective, blinded investigation, we included 152 coronary artery segments in 117 patients treated with a stent implant. All segments were evaluated by a dynamic EBCT study that depicted contrast bolus passage distal to the stent and a CT angiographic study of the entire coronary arteries. It was found that delayed contrast enhancement in the distal segment correlated with angiographic stent obstruction (Spearman's rank correlation, P=0.008), while all other indicators of stent occlusion did not correlate with angiographic diagnosis. However, direct comparison of patients with obstruction of less vs. more than 75% of luminal diameter did not yield any statistically significant differences of distal enhancement delay, and for the detection of >90% occlusion, the sensitivity was 72% at a specificity of 60%. Although delayed contrast enhancement distal to the stent upon EBCT did correlate with angiographical obstruction, the correlation did not suffice to appear clinically satisfactory.
authors.affiliation: Department of Radiology, Charité, Campus Virchow-Klinikum, Humboldt-University, Augustenburger Platz 1, 13353 Berlin, Germany. Friedrich.Knollmann@charite.de
authors.forename: Friedrich D
authors.initials: FD
authors.lastname: Knollmann
authors.forename: Jörg
authors.initials: J
authors.lastname: Möller
authors.forename: Axel
authors.initials: A
authors.lastname: Gebert
authors.forename: Christian
authors.initials: C
authors.lastname: Bethge
authors.forename: Roland
authors.initials: R
authors.lastname: Felix
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000008:administration & dosage; D017023:Coronary Angiography / Q000295:instrumentation / Q000379:methods*; D003326:Coronary Circulation / Q000502:physiology; D023903:Coronary Restenosis / Q000175:diagnosis*; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015607:Stents; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014654:Vascular Patency / Q000502:physiology
chemical_list: D003287:Contrast Media