Dynamic Myocardial CT Perfusion Imaging for Evaluation of Myocardial Ischemia as Determined by MR Imaging

• Published in: JACC. Cardiovascular imaging 2014-03, Vol.7 (3), p.267-277
• Main Authors: Bamberg, Fabian, MD, MPH, Marcus, Roy P., BS, Becker, Alexander, MD, Hildebrandt, Kristof, BS, Bauner, Kerstin, MD, Schwarz, Florian, MD, Greif, Martin, MD, von Ziegler, Franz, MD, Bischoff, Bernhard, MD, Becker, Hans-Christoph, MD, Johnson, Thorsten R., MD, Reiser, Maximilian F., MD, Nikolaou, Konstantin, MD, Theisen, Daniel, MD
• Format: Article
• Language: English
• Subjects: Aged; Cardiovascular; Coronary Angiography - methods; Coronary Artery Disease - diagnostic imaging; Coronary Artery Disease - physiopathology; Coronary Circulation; Diagnosis, Differential; Feasibility Studies; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Multidetector Computed Tomography; Myocardial Infarction - diagnostic imaging; Myocardial Infarction - physiopathology; Myocardial Perfusion Imaging - methods; Predictive Value of Tests; Prospective Studies; Regional Blood Flow
• ISSN: 1936-878X; 1876-7591
• DOI: 10.1016/j.jcmg.2013.06.008

Objectives 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.