title: Additional value of dipyridamole stress myocardial perfusion by 64-row computed tomography in patients with coronary stents.
abstract: BACKGROUND
  Coronary computed tomography angiography (CTA) is a well-established diagnostic tool for coronary artery disease (CAD). However, coronary segments with prior stent implantation visualized with CTA may have limited evaluation and reduced accuracy.
  
  
  OBJECTIVE
  We assessed the incremental value of stress myocardial CT perfusion (CTP) over anatomical assessment by coronary CTA alone in patients with stents, using quantitative invasive coronary angiography (≥50%) as reference.
  
  
  METHODS
  Forty-six patients (56.9 ± 7.2 years; 28 men) referred to invasive coronary angiography were evaluated, combining coronary CTA and dipyridamole stress myocardial CTP with 64 detector-row CT. Coronary CTA was evaluated for ≥50% coronary stenosis, and myocardial CTP was used to potentially reclassify coronary territories, including those with stents and poorly evaluated stents because of artifacts.
  
  
  RESULTS
  We evaluated 138 coronary territories, 62 with ≥1 stent. From these, 21 (34%) territories had adequately evaluated stents, 28 (45%) had limitedly evaluated stents still allowing diagnosis, and 13 (21%) had inadequately evaluated stents (no luminal assessment possible). Sensitivity, specificity, positive predictive value, negative predictive value and accuracy for coronary CTA in stent territories were, respectively, 85%, 77%, 87%, 74%, and 81%, and the combined use of coronary CTA and myocardial CTP were 88%, 95%, 97%, 81%, and 91% (P = 0.0292). In territories with impaired stent evaluation (limited or inadequate), the diagnostic performance of coronary CTA alone was 83%, 72%, 79%, 76% and 77%, and combined with myocardial CTP were 87%, 94%, 95%, 85%, and 91% (P = 0.036).
  
  
  CONCLUSIONS
  The combined evaluation of coronary CTA and stress myocardial CTP improved the diagnostic accuracy for the detection of significant obstructive CAD in patients with stents.
authors.affiliation: Cardiovascular MR and CT Section, Heart Institute (InCor), University of São Paulo Medical School, Av. Dr. Enéas de Carvalho Aguiar, 44 Andar AB, Cerqueira Cesar, São Paulo, 05403-000, Brazil.
authors.forename: Tiago A
authors.initials: TA
authors.lastname: Magalhães
authors.forename: Roberto C
authors.initials: RC
authors.lastname: Cury
authors.forename: Alexandre C
authors.initials: AC
authors.lastname: Pereira
authors.forename: Valéria de Melo
authors.initials: Vde M
authors.lastname: Moreira
authors.forename: Pedro A
authors.initials: PA
authors.lastname: Lemos
authors.forename: Roberto
authors.initials: R
authors.lastname: Kalil-Filho
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Rochitte
mesh_terms: D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects / Q000295:instrumentation*; D016477:Artifacts; D001938:Brazil; D016009:Chi-Square Distribution; D017023:Coronary Angiography; D003326:Coronary Circulation; D023903:Coronary Restenosis / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D004176:Dipyridamole; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity; D015607:Stents; D036542:Tomography, Spiral Computed; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents; D004176:Dipyridamole