Hung Guang-Uei, Lee Kung-Wei, Chen Ching-Pei, Yang Kuang-Tao, Lin Wan-Yu
Department of Nuclear Medicine, Changhua Christian Hospital, Changhua, Taiwan.
J Nucl Cardiol. 2006 Mar-Apr;13(2):225-32. doi: 10.1007/BF02971247.
Vasodilator stress on myocardial perfusion imaging has been found to induce ischemic stunning, which may present as transient worsening of left ventricular ejection fraction (LVEF) or regional wall motion abnormality. This study aimed to evaluate the significance of stress-induced worsening of LVEF in the diagnosis of coronary artery disease (CAD) on dipyridamole thallium 201 gated single photon emission computed tomography (SPECT).
The study included 126 patients who underwent dipyridamole Tl-201 gated SPECT and coronary angiography within 3 months. Poststress and 4-hour rest images were obtained, and LVEF was calculated by use of automated software (QGS 3.0). A decrease in LVEF of 6% or greater from rest to poststress was considered significant, and this threshold was determined by the serial reproducibility assessment of Tl-201 gated SPECT. If worsening of LVEF was used as the criterion for detecting significant CAD (> or = 70% coronary stenoses in > or = 1 vessel), the sensitivity, specificity, positive predictive value, and negative predictive value were 35%, 93%, 90%, and 44%, respectively.
Dipyridamole-induced worsening of LVEF, as shown by Tl-201 gated SPECT, is a valuable nonperfusion marker of significant CAD. Although the sensitivity of LVEF worsening in detecting significant CAD is only 35%, the specificity is as high as 93%.
心肌灌注成像中的血管扩张剂负荷已被发现可诱发缺血后心肌顿抑，这可能表现为左心室射血分数（LVEF）短暂恶化或节段性室壁运动异常。本研究旨在评估双嘧达莫铊201门控单光子发射计算机断层扫描（SPECT）中负荷诱导的LVEF恶化在冠状动脉疾病（CAD）诊断中的意义。
本研究纳入了126例在3个月内接受双嘧达莫铊201门控SPECT和冠状动脉造影的患者。获取负荷后及4小时静息图像，并使用自动化软件（QGS 3.0）计算LVEF。从静息到负荷后LVEF下降6%或更多被认为有意义，该阈值通过铊201门控SPECT的系列重复性评估确定。如果将LVEF恶化用作检测显著CAD（≥1支血管中冠状动脉狭窄≥70%）的标准，则敏感性、特异性、阳性预测值和阴性预测值分别为35%、93%、90%和44%。
铊201门控SPECT显示的双嘧达莫诱导的LVEF恶化是显著CAD的一种有价值的非灌注标志物。尽管LVEF恶化在检测显著CAD方面的敏感性仅为35%，但其特异性高达93%。
