Bestetti A, Triulzi A, Di Leo C, Tagliabue L, Del Sole A, Tarolo G L
Cattedra di Medicina Nucleare, Università degli Studi, Ospedale S. Paolo, Milano.
Radiol Med. 1999 Jan-Feb;97(1-2):48-53.
Gated SPECT using 99mTc-labeled flow tracers provides simultaneous assessment of global and regional myocardial function.
To investigate whether studying regional wall thickening after stress and at rest provides additional diagnostic information in coronary artery disease patients.
We examined 61 consecutive patients (40 men) who underwent conventional diagnostic dual day stress/rest Gated SPECT using a dual head SPECT camera, following injection of 925 MBq of 99mTc-Tetrofosmin. The mean age of these patients was 61 years (range: 23-73); 28 patients had a history of myocardial infarction. Perfusion was analyzed on both ungated and end-diastolic images using 20 segments scored on a 5-point scale (0 = normal, 4 = no uptake), while wall thickening and motion were assessed visually on stress/rest end-systolic images using a 4-point score (0 = normal, 3 = no wall thickening/motion). Twenty eight patients underwent coronary angiography.
14/61 (23%) patients showed no segmental defects, while fixed equivocal defects, with preserved wall thickening, in 10/61 (16%) patients were considered artifactual. 11/61 (18%) showed true fixed defects. The remaining 26 patients showed al least one reversible defect. 14/61 (23%) patients with post-stress wall thinning and normal rest wall thickness, were considered stunned. The stunned subgroup showed a significant post-stress reduction in left ventricular ejection fraction. Finally, analyzing 1220 segments, we found an excellent agreement (k = .697) between the segmental score obtained by end-diastolic and ungated post-stress images: in fact, comparing the two sets of images, diagnostic accuracy was not significantly different. However the number of segments with fixed defects and normal wall thickening was lower with end-diastolic perfusion images than with ungated images, probably due to attenuation artifacts. This suggests a better accuracy of the former in the evaluation of regional myocardial perfusion.
Although stress end-diastolic images do not seem to significantly improve diagnostic perfusion accuracy compared to ungated acquisitions, the simultaneous assessment of stress-rest wall thickening permits better characterization of a coronary artery disease population.
使用99mTc标记的血流示踪剂的门控单光子发射计算机断层扫描（SPECT）可同时评估整体和局部心肌功能。
研究在应激和静息状态下研究局部室壁增厚是否能为冠心病患者提供额外的诊断信息。
我们对61例连续患者（40例男性）进行了检查，这些患者在注射925MBq的99mTc-替曲膦后，使用双头SPECT相机进行了传统的诊断性双日应激/静息门控SPECT检查。这些患者的平均年龄为61岁（范围：23 - 73岁）；28例患者有心肌梗死病史。在非门控和舒张末期图像上分析灌注情况，采用20节段5分制评分（0 = 正常，4 = 无摄取），而在应激/静息收缩末期图像上通过4分制视觉评估室壁增厚和运动情况（0 = 正常，3 = 无室壁增厚/运动）。28例患者接受了冠状动脉造影。
14/61（23%）的患者未显示节段性缺损，而10/61（16%）的患者有固定的可疑缺损且室壁增厚保留，被认为是伪影。11/61（18%）显示真正的固定缺损。其余26例患者显示至少一个可逆性缺损。14/61（23%）的患者在应激后室壁变薄且静息时室壁厚度正常，被认为是心肌顿抑。心肌顿抑亚组在应激后左心室射血分数显著降低。最后，分析1220个节段，我们发现舒张末期和应激后非门控图像获得的节段评分之间有极好的一致性（k = 0.697）：实际上，比较两组图像，诊断准确性无显著差异。然而，舒张末期灌注图像中固定缺损且室壁增厚正常的节段数量比非门控图像少，可能是由于衰减伪影。这表明前者在评估局部心肌灌注方面准确性更高。
尽管与非门控采集相比，应激舒张末期图像似乎并未显著提高诊断灌注准确性，但应激 - 静息室壁增厚的同时评估能更好地表征冠心病患者群体。
