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Objective: To evaluate the feasibility of adenosine-stress dynamic myocardial volume perfusion imaging with second generation dual source computed tomography (CT) for the qualitative and quantitative assessment of myocardial blood flow (MBF) compared with stress perfusion and viability magnetic resonance imaging (MRI)., Material and Methods: Ten patients (8 male, 2 female, mean age 62.7 +/- 7.1 years) underwent stress/rest perfusion and delayed-enhancement MRI, and a cardiac CT protocol comprising prospectively electrocardiogram -triggered coronary CT angiography, dynamic adenosine-stress myocardial perfusion imaging using a "shuttle" mode, and delayed enhancement acquisitions. Two independent observers visually assessed myocardial perfusion defects. For semi-quantitative evaluation, CT- and MRI-derived myocardial-to-left ventricular upslope indices were compared. Additionally, absolute MBF was quantified based on dynamic perfusion CT and correlated with semi quantitative CT measurements. Myocardial perfusion analysis was performed on a segmental basis. Analysis used paired t tests, Wilcoxon signed-rank test, linear correlation, and Bland-Altman statistics., Results: A total of 149 segments (93.1%) were suitable for analysis. Sensitivity, specificity, positive and negative predictive values for detection of myocardial perfusion defects at CT compared with MRI were 86.1%, 98.2%, 93.9%, and 95.7%, respectively. Semiquantitative analysis of CT data showed significant differences between ischemic and nonischemic myocardium with a signal intensity upslope that was comparable with MRI-derived values (CT: 5.2 +/- 2 SI/s, MRI: 4.8 +/- 2.3 SI/s, P > 0.05). Moderate correlation was observed between absolute CT quantification of MBF and semi-quantitative CT measurements. Mean total dose length product for the entire cardiac CT protocol was 1290.4 +/- 233.3 mGy cm., Conclusion: Adenosine-stress volumetric first pass CT perfusion imaging is feasible and may enable the evaluation of qualitative and semi quantitative parameters of myocardial perfusion in a comparable fashion as MRI.

Recent research suggests that multidetector-row CT may have potential as a standalone modality for integrative imaging of coronary heart disease, including the assessment of the myocardial blood supply. However, the technical prerequisites for volumetric, time-resolved imaging of the passage of a contrast medium bolus through the myocardium have only been met with latest generation wide-detector CT scanners. Second-generation dual-source CT enables performing electrocardiographic (ECG)-synchronized dynamic myocardial perfusion imaging by a dedicated "shuttle" mode. With this acquisition mode, image data can be acquired during contrast medium infusion at 2 alternating table positions with the table shuttling back and forth between the 2 positions covering a 73-mm anatomic volume. We applied this acquisition technique for detecting differences in perfusion patterns between healthy and diseased myocardium and for quantifying myocardial blood flow under adenosine stress in 3 patients with coronary heart disease. According to our initial experience, the addition of adenosine stress volumetric dynamic CT perfusion to a cardiac CT protocol comprising coronary artery calcium quantification, prospectively ECG-triggered coronary CT angiography, and delayed acquisition appears promising for the comprehensive assessment of coronary artery luminal integrity, cardiac function, perfusion, and viability with a single modality., (Copyright 2010 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)