Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Drive, Charleston, SC 29401, USA.
Eur J Radiol. 2008 Dec;68(3):423-33. doi: 10.1016/j.ejrad.2008.09.010. Epub 2008 Nov 12.
The introduction of coronary CT angiography (cCTA) has reinvigorated the debate whether management of patients with suspected coronary artery disease (CAD) should be primarily based on physiological versus anatomical testing. Anatomical testing (i.e., cCTA or invasive catheterization) enables direct visualization and grading of coronary artery stenoses but has shortcomings for gauging the hemodynamic significance of lesions for myocardial perfusion. Conversely, rest/stress myocardial perfusion imaging (MPI) has been extensively validated for assessing the clinical significance of CAD by demonstrating fixed or reversible perfusion defects but has only limited anatomical information. There is early evidence that contrast medium enhanced dual-energy cCTA (DECT) has potential for the comprehensive analysis of coronary artery morphology as well as changes in myocardial perfusion. DECT exploits the fact that tissues in the human body and iodine-based contrast media have unique absorption characteristics when penetrated with different X-ray energy levels, which enables mapping the iodine (and thus blood) distribution within the myocardium. The purpose of this communication is to describe the practical application of this emerging technology for the comprehensive diagnosis of coronary artery disease in the context of the currently used tomographic imaging modalities (cCTA, nuclear MPI, MR MPI).
冠状动脉 CT 血管造影（cCTA）的引入重新引发了这样的争论，即疑似冠心病（CAD）患者的管理是否应主要基于生理或解剖测试。解剖测试（即 cCTA 或有创导管插入术）能够直接可视化和分级冠状动脉狭窄，但对于评估病变对心肌灌注的血流动力学意义存在缺陷。相反，静息/负荷心肌灌注成像（MPI）已通过显示固定或可逆的灌注缺陷广泛验证了用于评估 CAD 的临床意义，但仅具有有限的解剖信息。有早期证据表明，对比增强双能 cCTA（DECT）具有分析冠状动脉形态以及心肌灌注变化的综合分析的潜力。DECT 利用了人体组织和碘基造影剂在穿透不同 X 射线能级时具有独特的吸收特性这一事实，从而能够绘制心肌内碘（因此也是血液）的分布图。本通讯的目的是描述这项新兴技术在目前使用的层析成像方式（cCTA、核 MPI、MR MPI）的背景下，用于全面诊断冠状动脉疾病的实际应用。
