Dwivedi Girish, Liu Yingwei, Tewari Shrankhala, Inacio Joao, Pelletier-Galarneau Matthieu, Chow Benjamin J W
*Department of Medicine (Cardiology), University of Ottawa Heart Institute Departments of ‡Medicine †Radiology, University of Ottawa, ON, Canada.
J Thorac Imaging. 2016 Nov;31(6):373-379. doi: 10.1097/RTI.0000000000000236.
Coronary computed tomography (CT) angiography (CCTA) has the ability to detect, characterize, and quantify atherosclerotic plaques. The aim of our study was to evaluate the prognostic power of CCTA-quantified plaque subtypes.
A total of 36 patients with adverse events and 36 Morise score-matched patients who remained event free on follow-up were identified. Using CCTA images, plaque subtype volumes in the major epicardial arteries were analyzed using predetermined attenuation ranges in Hounsfield units (HU): 1 to 30 HU (low attenuating), 31 to 70 HU (intermediate attenuating), 71 to 150 HU (high attenuating), and mean coronary lumen+2 SD to 1000 HU (calcified). Each epicardial artery was divided into proximal, mid, and distal segments, and plaque volumes were normalized for arterial segment length.
The baseline characteristics of the 2 cohorts were similar. Low-attenuation and intermediate-attenuation plaque volumes were greater in the proximal segments as well as in the entire length in the adverse event compared with the event-free group. High-attenuation plaque volume was increased only in the proximal segments in the adverse event group. There was no difference in the volume of calcified plaque between the 2 groups. The log rank test using a cutoff of 3.99 mm/mm for combined intermediate and low plaque volume showed more adverse events in patients with a plaque volume of ≥3.99 mm/mm.
Adverse events appear to be associated with greater volumes of low-attenuation and intermediate-attenuation plaques that reflect lipid and fibrous atherosclerosis. The difference between the 2 groups is most apparent in the proximal epicardial arteries.
冠状动脉计算机断层扫描（CT）血管造影（CCTA）能够检测、表征和量化动脉粥样硬化斑块。我们研究的目的是评估CCTA量化的斑块亚型的预后能力。
共纳入36例发生不良事件的患者以及36例Morise评分匹配且随访期间无事件发生的患者。使用CCTA图像，根据预先设定的亨氏单位（HU）衰减范围分析主要心外膜动脉中的斑块亚型体积：1至30 HU（低衰减）、31至70 HU（中等衰减）、71至150 HU（高衰减）以及平均冠状动脉管腔+2标准差至1000 HU（钙化）。将每条心外膜动脉分为近端、中段和远端节段，并将斑块体积按动脉节段长度进行标准化。
两组的基线特征相似。与无事件组相比，不良事件组近端节段以及整个长度的低衰减和中等衰减斑块体积更大。不良事件组仅近端节段的高衰减斑块体积增加。两组之间钙化斑块体积无差异。使用中等和低斑块体积总和的截断值3.99 mm/mm进行对数秩检验显示，斑块体积≥3.99 mm/mm的患者不良事件更多。
不良事件似乎与反映脂质和纤维性动脉粥样硬化的低衰减和中等衰减斑块体积增大有关。两组之间的差异在心外膜动脉近端最为明显。
