title: Cardiovascular magnetic resonance perfusion imaging at 3-tesla for the detection of coronary artery disease: a comparison with 1.5-tesla.
abstract: OBJECTIVE
  This study was designed to establish the diagnostic accuracy of cardiovascular magnetic resonance (CMR) perfusion imaging at 3-Tesla (T) in suspected coronary artery disease (CAD).
  
  
  BACKGROUND
  Myocardial perfusion imaging is considered one of the most compelling applications for CMR at 3-T. The 3-T systems provide increased signal-to-noise ratio and contrast enhancement (compared with 1.5-T), which can potentially improve spatial resolution and image quality.
  
  
  METHODS
  Sixty-one patients (age 64 +/- 8 years) referred for elective diagnostic coronary angiography (CA) for investigation of exertional chest pain were studied (before angiogram) with first-pass perfusion CMR at both 1.5- and 3-T and at stress (140 microg/kg/min intravenous adenosine, Adenoscan, Sanofi-Synthelabo, Guildford, United Kingdom) and rest. Four short-axis images were acquired during every heartbeat using a saturation recovery fast-gradient echo sequence and 0.04 mmol/kg Gd-DTPA bolus injection. Quantitative CA served as the reference standard. Perfusion deficits were interpreted visually by 2 blinded observers. We defined CAD angiographically as the presence of > or =1 stenosis of > or =50% diameter in any of the main epicardial coronary arteries or their branches with a diameter of > or =2 mm.
  
  
  RESULTS
  The prevalence of CAD was 66%. All perfusion images were found to be visually interpretable for diagnosis. We found that 3-T CMR perfusion imaging provided a higher diagnostic accuracy (90% vs. 82%), sensitivity (98% vs. 90%), specificity (76% vs. 67%), positive predictive value (89% vs. 84%), and negative predictive value (94% vs. 78%) for detection of significant coronary stenoses compared with 1.5-T. The diagnostic performance of 3-T perfusion imaging was significantly greater than that of 1.5-T in identifying both single-vessel disease (area under receiver-operator characteristic [ROC] curve: 0.89 +/- 0.05 vs. 0.70 +/- 0.08; p < 0.05) and multivessel disease (area under ROC curve: 0.95 +/- 0.03 vs. 0.82 +/- 0.06; p < 0.05). There was no difference between field strengths for the overall detection of coronary disease (area under ROC curve: 0.87 +/- 0.05 vs. 0.78 +/- 0.06; p = 0.23).
  
  
  CONCLUSIONS
  Our study showed that 3-T CMR perfusion imaging is superior to 1.5-T for prediction of significant single- and multi-vessel coronary disease, and 3-T may become the preferred CMR field strength for myocardial perfusion assessment in clinical practice.
authors.affiliation: University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom.
authors.forename: Adrian S H
authors.initials: AS
authors.lastname: Cheng
authors.forename: Tammy J
authors.initials: TJ
authors.lastname: Pegg
authors.forename: Theodoros D
authors.initials: TD
authors.lastname: Karamitsos
authors.forename: Nick
authors.initials: N
authors.lastname: Searle
authors.forename: Michael
authors.initials: M
authors.lastname: Jerosch-Herold
authors.forename: Robin P
authors.initials: RP
authors.lastname: Choudhury
authors.forename: Adrian P
authors.initials: AP
authors.lastname: Banning
authors.forename: Stefan
authors.initials: S
authors.lastname: Neubauer
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Robson
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Selvanayagam
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003287:Contrast Media / Q000008:administration & dosage*; D017023:Coronary Angiography / Q000379:methods; D003324:Coronary Artery Disease / Q000175:diagnosis*; D005080:Exercise Test; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography / Q000379:methods; D019028:Magnetic Resonance Imaging, Cine / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011336:Probability; D011446:Prospective Studies; D012372:ROC Curve; D011856:Radiographic Image Enhancement; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D003287:Contrast Media