Mor-Avi Victor, Lodato Joseph A, Kachenoura Nadjia, Chandra Sonal, Freed Benjamin H, Newby Barbara, Lang Roberto M, Patel Amit R
University of Chicago Medical Center, Chicago, IL 60637, USA.
J Comput Assist Tomogr. 2012 Jul-Aug;36(4):443-9. doi: 10.1097/RCT.0b013e31825833a3.
The ability of multidetector computed tomography (MDCT) to detect stress-induced myocardial perfusion abnormalities is of great clinical interest as a potential tool for the combined evaluation of coronary stenosis and its hemodynamic significance. We tested the hypothesis that quantitative 3-dimensional (3D) analysis of myocardial perfusion from MDCT images obtained during regadenoson stress would more accurately detect the presence of significant coronary artery disease (CAD) than identical analysis when performed on resting MDCT images.
We prospectively studied 50 consecutive patients referred for CT coronary angiography (CTCA) who agreed to undergo additional imaging with regadenoson (0.4 mg; Astellas). Images were acquired using prospective gating (256-channel; Philips). Custom analysis software was used to define 3D myocardial segments, and calculate for each segment an index of severity and extent of perfusion abnormality, Qh, which was compared with perfusion defects predicted by the presence and severity of coronary stenosis on CTCA.
Three patients were excluded because of image artifacts. In the remaining 47 patients, CTCA depicted stenosis more than 50% in 23 patients in 37 of 141 coronary arteries. In segments supplied by the obstructed arteries, myocardial attenuation was slightly reduced compared with normally perfused segments at rest (mean [SD], 91 [21] vs 93 [26] Hounsfield units, not significant) and, to a larger extent, at peak stress (102 [21] vs 112 [20] Hounsfield units, P < 0.05). In contrast, index Qh was significantly increased at rest (0.40 [0.48] vs 0.26 [0.41], P < 0.05) and reached a nearly 3-fold difference at peak stress (0.66 [0.74] vs 0.28 [0.51], P < 0.05). The addition of regadenoson improved the diagnosis of CAD, as reflected by an increase in sensitivity (from 0.57 to 0.91) and improvement in accuracy (from 0.65 to 0.77).
Quantitative 3D analysis of MDCT images allows objective detection of CAD, the accuracy of which is improved by regadenoson stress.
多排螺旋计算机断层扫描（MDCT）检测应激诱导的心肌灌注异常的能力，作为一种联合评估冠状动脉狭窄及其血流动力学意义的潜在工具，具有重要的临床价值。我们检验了这样一个假设：与静息MDCT图像分析相比，对瑞加诺生负荷期间获得的MDCT图像进行心肌灌注的定量三维（3D）分析，能更准确地检测出显著冠状动脉疾病（CAD）的存在。
我们前瞻性地研究了50例连续接受CT冠状动脉造影（CTCA）检查且同意接受瑞加诺生（0.4 mg；安斯泰来）额外成像检查的患者。使用前瞻性门控（256排；飞利浦）采集图像。使用定制分析软件定义3D心肌节段，并计算每个节段的灌注异常严重程度和范围指数Qh，将其与CTCA上冠状动脉狭窄的存在和严重程度所预测的灌注缺损进行比较。
3例患者因图像伪影被排除。在其余47例患者中，CTCA显示141支冠状动脉中的37支有23例患者存在超过50%的狭窄。在阻塞动脉供血的节段，静息时与正常灌注节段相比，心肌衰减略有降低（平均值[标准差]，91[21]对93[26]亨氏单位，无显著差异），而在负荷峰值时降低程度更大（102[21]对112[20]亨氏单位，P<0.05）。相比之下，指数Qh在静息时显著升高（0.40[0.48]对0.26[0.41]，P<0.05），在负荷峰值时达到近3倍差异（0.66[0.74]对0.28[0.51]，P<0.05）。瑞加诺生的加入改善了CAD的诊断，表现为敏感性增加（从0.57提高到0.91）和准确性提高（从0.65提高到0.77）。
MDCT图像的定量3D分析能够客观检测CAD，瑞加诺生负荷可提高其准确性。
