title: Incremental value of an integrated adenosine stress-rest MDCT perfusion protocol for detection of obstructive coronary artery disease.
abstract: BACKGROUND
  Preliminary studies have shown the potential of myocardial computed tomography perfusion (CTP) analysis for ischemia detection in both animals and humans.
  
  
  OBJECTIVE
  To provide validation data on stress-rest CTP protocols as additive tools to improve the accuracy of multidetector computed tomography (MDCT) for coronary artery disease (CAD) in symptomatic patients.
  
  
  METHODS
  Ninety symptomatic patients with suspected CAD (62 ± 8 years, 66% males) underwent both MDCT and invasive coronary angiography (XA). The MDCT protocol included a prospective calcium score acquisition, a helical acquisition with retrospective gating during infusion of adenosine (140 μg/kg/min) and a prospective scan for computed tomography angiography (CTA) at rest (total effective radiation dose: 5.1 ± 0.8 mSv). Significant and higher-grade CADs were defined by the presence of ≥50% or ≥70% stenosis in at least one coronary artery, as evaluated by quantitative coronary angiography (QCA) using XA images.
  
  
  RESULTS
  On a patient-based model, CTA sensitivity, specificity, and positive (PPV) and negative predictive values (NPV) to detect ≥50% or ≥70% stenosis were 98%, 71%, 80%, and 97% (global accuracy 86%) and 100%, 60%, 64%, and 100% (accuracy 77%), respectively. An integrative approach of CTA and CTP results had the best performance for detection of CAD with sensitivity of 83%, specificity of 98%, PPV of 98%, and NPV of 84% (accuracy 84%) for detection of 50% stenosis and 97%, 90%, 88%, and 98% (accuracy 93%), respectively, for the 70% threshold. The integration of results had the best overall performance in all scenarios but was particularly advantageous in the prediction of higher-grade CAD, with an area under the curve of 0.93, compared with 0.80 for isolated CTA and 0.82 for CTP and in patients with severe calcifications (sensitivity 92%, specificity 87%, overall accuracy of 90%).
  
  
  CONCLUSIONS
  The integration of functional and morphological data using CTA and CTP improved MDCT accuracy for detection of clinically relevant CAD at both thresholds of 50% and 70% in this intermediate to high pretest probability population.
authors.affiliation: Department of Cardiology, Centro Hospitalar de Gaia/Espinho, EPE, Rua Conceição Fernandes, 4434-502 Vila Nova de Gaia, Portugal. bettencourt.n@gmail.com
authors.forename: Nuno
authors.initials: N
authors.lastname: Bettencourt
authors.forename: João
authors.initials: J
authors.lastname: Rocha
authors.forename: Nuno
authors.initials: N
authors.lastname: Ferreira
authors.forename: Gustavo
authors.initials: G
authors.lastname: Pires-Morais
authors.forename: Mónica
authors.initials: M
authors.lastname: Carvalho
authors.forename: Daniel
authors.initials: D
authors.lastname: Leite
authors.forename: Bruno
authors.initials: B
authors.lastname: Melica
authors.forename: Lino
authors.initials: L
authors.lastname: Santos
authors.forename: Alberto
authors.initials: A
authors.lastname: Rodrigues
authors.forename: Pedro
authors.initials: P
authors.lastname: Braga
authors.forename: Madalena
authors.initials: M
authors.lastname: Teixeira
authors.forename: Lino
authors.initials: L
authors.lastname: Simões
authors.forename: Adelino
authors.initials: A
authors.lastname: Leite-Moreira
authors.forename: Silva
authors.initials: S
authors.lastname: Cardoso
authors.forename: Eike
authors.initials: E
authors.lastname: Nagel
authors.forename: Vasco
authors.initials: V
authors.lastname: Gama
mesh_terms: D000241:Adenosine; D000328:Adult; D000368:Aged; D017023:Coronary Angiography; D003326:Coronary Circulation; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D011174:Portugal; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D036542:Tomography, Spiral Computed; D061205:Vascular Calcification / Q000000981:diagnostic imaging / Q000503:physiopathology; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents; D000241:Adenosine