Department of Radiology, College of Medicine, Dong-A University, Busan, Korea.
Department of Cardiology, College of Medicine, Dong-A University, Busan, Korea.
Korean J Radiol. 2020 Dec;21(12):1285-1293. doi: 10.3348/kjr.2019.0908. Epub 2020 Aug 4.
To evaluate the effects of vasodilators on contrast enhancement and transluminal attenuation gradient (TAG) of coronary arteries at coronary computed tomography angiography (CCTA).
We retrospectively reviewed CCTA scans of patients who underwent double-acquisition CCTA; CCTA without a vasodilator, and CCTA during a intravenous (IV) infusion of nitrate. Among them, we enrolled 19 patients who had no significant atherosclerotic lesions or coronary spasms. In the control group, 28 patients were enrolled who showed normal coronary arteries on CCTA, which was acquired by a conventional method (sublingual vasodilator). We measured the TAG and Hounsfield units for each of the three major epicardial coronary arteries (reported as 'ProxHU') and then compared the results between the nitrate administration methods (CT without vasodilator [CT], CT with IV vasodilator [CT], and CT with sublingual vasodilator [CT]).
The mean TAG showed a significant difference between the coronary arteries (right coronary artery [RCA] > left anterior descending artery [LAD] > left circumflex artery [LCX], < 0.05), while there was no difference in ProxHU of each coronary artery in all three types of nitrate administration methods ( > 0.05). The TAG of CT group showed steeper slope than those of vasodilator groups (CT and CT) on LAD and LCX ([LAD: CT = -22.1 ± 6.66, CT = -16.76 ± 5.78, and CT = -16.47 ± 5.78, = 0.005], [LCX: CT = -31.26 ± 17.43, CT = -23.74 ± 14.06, and CT = -20.94 ± 12.15, = 0.051]), while that of RCA showed no significant differences ( = 0.600). When comparing proxHU, CT showed higher proxHU than that of CT or CT, especially on LCX (CT = 426.7 ± 68.3, CT = 467.9 ± 84.9, and CT = 404.9 ± 63.3, = 0.013). ProxHU showed a negative correlation with TAG on all three of methods (r = -0.280, < 0.001).
TAG in CCTA was significantly affected by vasodilator administration. Both TAG and ProxHU of coronary arteries tend to increase with vasodilator administration on CCTA.
评估血管扩张剂对冠状动脉 CT 血管造影（CCTA）中对比增强和管腔衰减梯度（TAG）的影响。
我们回顾性分析了行双期 CCTA 检查的患者的 CCTA 扫描资料，其中包括无血管扩张剂的 CCTA 检查和静脉（IV）输注硝酸盐后的 CCTA 检查。在这些患者中，我们纳入了 19 名无明显动脉粥样硬化病变或冠状动脉痉挛的患者。在对照组中，我们纳入了 28 名 CCTA 显示正常冠状动脉的患者，这些患者接受了常规方法（舌下含服血管扩张剂）的检查。我们测量了三支主要心外膜冠状动脉的 TAG 和亨氏单位（报告为“ProxHU”），然后比较了三种硝酸盐给药方法（无血管扩张剂 CT [CT]、IV 血管扩张剂 CT [CT]和舌下含服血管扩张剂 CT [CT]）之间的结果。
三支冠状动脉的 TAG 存在显著差异（右冠状动脉 [RCA]＞左前降支 [LAD]＞左回旋支 [LCX]， < 0.05），而三种硝酸盐给药方法下的各支冠状动脉的 ProxHU 无差异（ > 0.05）。与血管扩张剂组（CT 和 CT）相比，CT 组的 LAD 和 LCX 的 TAG 斜率更陡（[LAD：CT = -22.1 ± 6.66，CT = -16.76 ± 5.78，CT = -16.47 ± 5.78， = 0.005]，[LCX：CT = -31.26 ± 17.43，CT = -23.74 ± 14.06，CT = -20.94 ± 12.15， = 0.051]），而 RCA 的 TAG 无显著差异（ = 0.600）。在比较 ProxHU 时，CT 显示的 ProxHU 高于 CT 或 CT，尤其是在 LCX（CT = 426.7 ± 68.3，CT = 467.9 ± 84.9，CT = 404.9 ± 63.3， = 0.013）。在三种方法中，ProxHU 与 TAG 均呈负相关（r = -0.280， < 0.001）。
CCTA 中的 TAG 明显受血管扩张剂给药的影响。在 CCTA 中，随着血管扩张剂的给药，冠状动脉的 TAG 和 ProxHU 均呈上升趋势。
