Quantitative Assessment of Coronary Plaques by Coronary CT Angiography: High Inter-Reader and Intra-Reader Agreement is Achieved but Inter-Scanner Variability should not be Ignored

Abstract

CitationSun Z. Quantitative assessment of coronary plaques by coronary CT angiography: High inter-reader and intra-reader agreement is achieved but inter-scanner variability should not be ignored. Heart Res Open J. 2017; 4(1): e1-e5. doi: 10.17140/HROJ-4-e007 ABSTRACTThis editorial discusses a recent paper published in the December issue of Radiology 2016 on the quantitative assessment of coronary plaques by coronary computed tomography (CT) angiography. Three main findings are discussed in the editorial: First, coronary CT angiography is an accurate imaging modality for analysis of plaque volume as well as monitoring volume change, with excellent inter-and intra-reader agreement with use of the state-of-the-art CT scanners. Second, the reliability of coronary CT angiography is noticed for low scan variability when plaque volume assessment is performed with the same vendor, but with high variability of nearly 30% when assessment is conducted with different vendors at baseline and follow-up scans. Finally, a large sample size is required to assess non-calcified plaques, in particular with use of different vendors.KEY WORDS: Coronary artery disease; Coronary CT angiography; Coronary plaque; Volume measurement; Variability.Coronary CT angiography (CCTA) is currently a widely used imaging modality for the diagnostic assessment of patients with suspected coronary artery disease (CAD) with high diagnostic accuracy reported in the literature.1-5 Rapid technological developments on cardiac CT imaging have occurred over the last decade which have led to the development and improvement of diagnostic spectrum of CCTA in the quantitative analysis of coronary plaques, in addition to the diagnostic value of coronary artery stenosis. These included characterization of plaque features and the corresponding clinical outcomes such as prediction of major adverse cardiac events, in addition to the routine assessment of coronary lumen stenosis. [6][7][8][9] Detection of plaque components, in particular, differentiation of non-calcified (vulnerable) from calcified (stable) plaques is more significant than detection of lumen stenosis because close association has been reported between plaque composition and myocardial ischemia and development of adverse cardiac events.10-13 Therefore, the current research direction of CCTA has primarily focused on the quantitative assessment of plaque features instead of coronary lumen analysis because the degree of lumen stenosis is not always associated with myocardial ischemic changes. 14,15Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) are two imaging modalities which allow excellent plaque characterization by providing intravascular views of plaque components, however, both are invasive, thus, they are not commonly performed in clinical practice. As a less invasive modality with widespread use in daily practice, CCTA is able to provide quantitative assessment of plaque morphology and components which add

Quantitative Coronary Plaque Characterization With Multidetector Ct Angiography

“…There is a growing evidence to show that CTCA has good correlation with IVUS in the quantitative plaque analysis (3) .…”

“…Non-calcified or low-attenuating plaques were more often seen in patients associated with acute coronary syndrome or development of major adverse cardiac events when compared to those with stable angina pectoris. Therefore, assessment of non-calcified plaque in terms of total plaque volume has significant clinical value (3) .…”