title: Dynamic myocardial CT perfusion imaging for evaluation of myocardial ischemia as determined by MR imaging.
abstract: OBJECTIVE
  The aim of this study was to determine the feasibility of computed tomography (CT)-based dynamic myocardial perfusion imaging for the assessment of myocardial ischemia and infarction compared with cardiac magnetic resonance (CMR).
  
  
  BACKGROUND
  Sequential myocardial CT perfusion imaging has emerged as a novel imaging technique for the assessment of myocardial hypoperfusion.
  
  
  METHODS
  We prospectively enrolled subjects with known coronary artery disease who underwent adenosine-mediated stress dynamic dual-source CT (100 kV, 320 mAs/rot) and CMR (3-T). Estimated myocardial blood flow (eMBF) and estimated myocardial blood volume (eMBV) were derived from CT images, using a model-based parametric deconvolution technique. The values were independently related to perfusion defects (ischemic and/or infarcted myocardial segments) as visually assessed during rest/stress and late gadolinium enhancement CMR. Conventional measures of diagnostic accuracy and differences in eMBF/eMBV were determined.
  
  
  RESULTS
  Of 38 enrolled subjects, 31 (mean age 70.4 ± 9.3 years; 77% men) completed both CT and CMR protocols. The prevalence of ischemic and infarcted myocardial segments detected by CMR was moderate (11.6%, n = 56 and 12.6%, n = 61, respectively, of 484 analyzed segments, with 8.4% being transmural). The diagnostic accuracy of CT for the detection of any perfusion defect was good (eMBF threshold, 88 ml/mg/min; sensitivity, 77.8% [95% confidence interval (CI): 69% to 85%]; negative predictive value, 91.3% [95% CI: 86% to 94%]) with moderate positive predictive value (50.6% [95% CI: 43% to 58%] and specificity (75.41% [95% CI: 70% to 79%]). Higher diagnostic accuracy was observed for transmural perfusion defects (sensitivity 87.8%; 95% CI: 74% to 96%) and infarcted segments (sensitivity 85.3%; 95% CI: 74% to 93%). Although eMBF in high-quality examinations was lower but not different between ischemic and infarcted segments (72.3 ± 18.7 ml/100 ml/min vs. 73.1 ± 31.9 ml/100 ml/min, respectively, p > 0.05), eMBV was significantly lower in infarcted segments compared with ischemic segments (11.3 ± 3.3 ml/100 ml vs. 18.4 ± 2.8 ml/100 ml, respectively; p < 0.01).
  
  
  CONCLUSIONS
  Compared with CMR, dynamic stress CT provides good diagnostic accuracy for the detection of myocardial perfusion defects and may differentiate ischemic and infarcted myocardium.
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany; Munich Heart Alliance, Munich, Germany. Electronic address: fbamberg@med.lmu.de.
authors: Fabian
authors: F
authors: Bamberg
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany.
authors: Roy P
authors: RP
authors: Marcus
authors: Department of Cardiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany.
authors: Alexander
authors: A
authors: Becker
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany.
authors: Kristof
authors: K
authors: Hildebrandt
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany.
authors: Kerstin
authors: K
authors: Bauner
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany; Munich Heart Alliance, Munich, Germany.
authors: Florian
authors: F
authors: Schwarz
authors: Department of Cardiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany.
authors: Martin
authors: M
authors: Greif
authors: Department of Cardiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany.
authors: Franz
authors: F
authors: von Ziegler
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany.
authors: Bernhard
authors: B
authors: Bischoff
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany; Munich Heart Alliance, Munich, Germany.
authors: Hans-Christoph
authors: HC
authors: Becker
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany.
authors: Thorsten R
authors: TR
authors: Johnson
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany; Munich Heart Alliance, Munich, Germany.
authors: Maximilian F
authors: MF
authors: Reiser
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany; Munich Heart Alliance, Munich, Germany.
authors: Konstantin
authors: K
authors: Nikolaou
authors: Department of Clinical Radiology, Ludwig-Maximilians-University, Klinikum Grosshadern, Munich, Germany; Munich Heart Alliance, Munich, Germany.
authors: Daniel
authors: D
authors: Theisen
mesh_terms: D000368:Aged; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003326:Coronary Circulation; D003937:Diagnosis, Differential; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000503:physiopathology; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012039:Regional Blood Flow
keywords: cardiac CT; cardiac MR; infarct; ischemia; myocardial perfusion