title: Functional compared to anatomical imaging in the initial evaluation of patients with suspected coronary artery disease: An international, multi-center, randomized controlled trial (IAEA-SPECT/CTA study).
abstract: To test the hypothesis that, in the initial evaluation of patients with suspected coronary artery disease (CAD), stress myocardial perfusion imaging (MPI) would result in less downstream testing than coronary computed tomographic angiography (CCTA).
  
  
  
  In this international, randomized trial, mildly symptomatic patients with an intermediate likelihood of having CAD, and asymptomatic patients at intermediate risk of cardiac events, underwent either initial stress-rest MPI or CCTA. The primary outcome was downstream noninvasive or invasive testing at 6 months. Secondary outcomes included cumulative effective radiation dose (ERD) and costs at 12 months.
  
  
  
  We recruited 303 patients (151 MPI and 152 CTA) from 6 centers in 6 countries. The initial MPI was abnormal in 29% (41/143) and CCTA in 56% (79/141) of patients. Fewer patients undergoing initial stress-rest MPI had further downstream testing at 6 months (adjusted OR 0.51, 95% CI 0.28-0.91, P = 0.023). There was a small increase in the median cumulative ERD with MPI (9.6 vs. 8.8 mSv, P = 0.04), but no difference in costs between the two strategies at 12 months.
  
  
  
  In the management of patients with suspected CAD, a strategy of initial stress MPI is substantially less likely to require further downstream testing than initial testing with CCTA.
  
  
  
  clinicaltrials.gov identification number NCT01368770.
authors: Department of Cardiology, All India Institute of Medical Sciences, New Delhi, 110029, India. karthik2010@gmail.com.
authors: Ganesan
authors: G
authors: Karthikeyan
authors: Department of Nuclear Medicine, University Medical Centre Ljubljana, Ljubljana, Slovenia.
authors: Barbara
authors: B
authors: Guzic Salobir
authors: Department of Vascular Medicine, University Medical Centre Ljubljana, Ljubljana, Slovenia.
authors: Borut
authors: B
authors: Jug
authors: Indian Institute of Public Health-Delhi, Gurgaon, India.
authors: Niveditha
authors: N
authors: Devasenapathy
authors: Department of Nuclear Medicine, Ignacio Chávez National Institute of Cardiology, Mexico City, Mexico.
authors: Erick
authors: E
authors: Alexanderson
authors: Quanta Diagnóstico & Terapia, Curitiba, Brazil.
authors: Joao
authors: J
authors: Vitola
authors: Department of Nuclear Medicine, Faculty Hospital Ostrava, Ostrava, Czech Republic.
authors: Otakar
authors: O
authors: Kraft
authors: Department of Nuclear Medicine, Ankara University Medical Faculty, Ankara, Turkey.
authors: Elgin
authors: E
authors: Ozkan
authors: Indian Institute of Public Health-Delhi, Gurgaon, India.
authors: Saket
authors: S
authors: Sharma
authors: Department of Cardiology, All India Institute of Medical Sciences, New Delhi, 110029, India.
authors: Gaurav
authors: G
authors: Purohit
authors: Department of Nuclear Medicine, University Medical Centre Ljubljana, Ljubljana, Slovenia.
authors: Maja
authors: M
authors: Dolenc Novak
authors: Department of Radiology, Ignacio Chávez National Institute of Cardiology, Mexico City, Mexico.
authors: Aloha
authors: A
authors: Meave
authors: Department of Nuclear Medicine, Ignacio Chávez National Institute of Cardiology, Mexico City, Mexico.
authors: Sergio
authors: S
authors: Trevethan
authors: Quanta Diagnóstico & Terapia, Curitiba, Brazil.
authors: Rodrigo
authors: R
authors: Cerci
authors: Quanta Diagnóstico & Terapia, Curitiba, Brazil.
authors: Sandra
authors: S
authors: Zier
authors: Department of Cardiology, Faculty Hospital Ostrava, Ostrava, Czech Republic.
authors: Lucia
authors: L
authors: Gotthardtová
authors: Department of Radiology, Faculty Hospital Ostrava, Ostrava, Czech Republic.
authors: Tomáš
authors: T
authors: Jonszta
authors: Department of Cardiology, Ankara University Medical Faculty, Ankara, Turkey.
authors: Timucin
authors: T
authors: Altin
authors: Department of Nuclear Medicine, Ankara University Medical Faculty, Ankara, Turkey.
authors: Cigdem
authors: C
authors: Soydal
authors: Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India.
authors: Chetan
authors: C
authors: Patel
authors: Department of Cardiac Radiology, All India Institute of Medical Sciences, New Delhi, India.
authors: Gurpreet
authors: G
authors: Gulati
authors: Division of Human Health, Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Vienna, Austria.
authors: Diana
authors: D
authors: Paez
authors: Division of Human Health, Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Vienna, Austria.
authors: Maurizio
authors: M
authors: Dondi
authors: Division of Human Health, Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Vienna, Austria.
authors: Ravi
authors: R
authors: Kashyap
mesh_terms: D000072226:Computed Tomography Angiography / Q000379:methods*; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000473:pathology*; D042241:Early Diagnosis; D005260:Female; D006334:Heart Function Tests / Q000379:methods*; D006801:Humans; D038622:Internationality; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Myocardial perfusion imaging—SPECT; computed tomography; coronary artery disease