Mazzanti M, Germano G, Kiat H, Kavanagh P B, Alexanderson E, Friedman J D, Hachamovitch R, Van Train K F, Berman D S
Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California, USA.
J Am Coll Cardiol. 1996 Jun;27(7):1612-20. doi: 10.1016/0735-1097(96)00052-6.
This study sought to assess whether a transient ischemic dilation ratio, determined from automatically derived stress and rest left ventricular volumes during stress technetium-99m (Tc-99m) sestamibi/rest thallium-201 dual-isotope myocardial perfusion single-photon emission computed tomography (SPECT), is useful for the identification of patients with severe and extensive coronary artery disease.
Transient ischemic dilation of the left ventricle on stress/redistribution thallium-201 scintigraphy has been shown to be a clinically useful marker of severe and extensive coronary artery disease. However, in practice, its assessment is highly subjective. This study automatically assessed the transient ischemic dilation ratio on the basis of a previously described algorithm to estimate three-dimensional ventricular boundaries.
Normal limits for the transient ischemic dilation ratio were developed using data from 54 patients with a low likelihood (< 5%) of coronary artery disease, and criteria for abnormality were developed based on data from 97 who under-went catheterization, of whom 34 had severe and extensive coronary artery disease, defined as > or = 90% stenosis in the proximal left anterior descending coronary artery or in two or more coronary arteries, and 63 had no coronary artery disease (15 patients) or mild to moderate coronary artery disease (48 patients). The criteria were then tested in a validation cohort of 77 additional patients who underwent catheterization, of whom 36 had severe and extensive coronary artery disease. The quantitative results of the dilation ratio were compared with the visual results of the dilation ratio and perfusion defect analysis.
For normal limits, receiver operating characteristic curve analysis showed that abnormal transient ischemic dilation ratio values corresponded to left ventricular endocardial volume ratios > 1.22 (mean +/- 2 SD). Transient ischemic dilation assessment using these criteria for abnormality showed high sensitivity (24 [71%] of 34) and very high specificity (60 [95%] of 63) for severe and extensive coronary artery disease. When the analysis was applied to the prospective catheterization group, similar sensitivity and specificity for severe and extensive coronary artery disease were observed (77% and 92%, respectively). Significant agreement (p = 0.0001) was found between the degree of transient ischemic dilation and the Tc-99m sestamibi defect extent, the latter assessed by semiquantitative visual analysis (summed stress score).
The automatic measurement of transient ischemic dilation in dual-isotope myocardial perfusion SPECT is a clinically useful marker that is sensitive and highly specific for detection of severe and extensive coronary artery disease.
本研究旨在评估通过应力锝-99m（Tc-99m）甲氧基异丁基异腈/静息铊-201双同位素心肌灌注单光子发射计算机断层扫描（SPECT）期间自动得出的应力和静息左心室容积所确定的短暂性缺血性扩张率，是否有助于识别患有严重广泛冠状动脉疾病的患者。
静息/再分布铊-201闪烁扫描显示的左心室短暂性缺血性扩张已被证明是严重广泛冠状动脉疾病的一种临床有用标志物。然而，在实际应用中，其评估具有高度主观性。本研究基于先前描述的用于估计三维心室边界的算法自动评估短暂性缺血性扩张率。
使用来自54例冠状动脉疾病可能性低（<5%）的患者的数据制定短暂性缺血性扩张率的正常范围，并根据97例接受导管检查的患者的数据制定异常标准，其中34例患有严重广泛冠状动脉疾病，定义为左前降支近端或两支或更多支冠状动脉狭窄≥90%，63例无冠状动脉疾病（15例患者）或患有轻度至中度冠状动脉疾病（48例患者）。然后在另外77例接受导管检查的患者的验证队列中测试这些标准，其中36例患有严重广泛冠状动脉疾病。将扩张率的定量结果与扩张率的视觉结果及灌注缺损分析进行比较。
对于正常范围，受试者工作特征曲线分析表明，异常的短暂性缺血性扩张率值对应于左心室内膜容积比>1.22（平均值±2标准差）。使用这些异常标准进行短暂性缺血性扩张评估显示，对于严重广泛冠状动脉疾病具有高敏感性（34例中的24例[71%]）和非常高的特异性（63例中的60例[95%]）。当将该分析应用于前瞻性导管检查组时，观察到对于严重广泛冠状动脉疾病具有相似的敏感性和特异性（分别为77%和92%）。在短暂性缺血性扩张程度与Tc-99m甲氧基异丁基异腈缺损范围之间发现显著一致性（p = 0.0001），后者通过半定量视觉分析（总应力评分）进行评估。
双同位素心肌灌注SPECT中短暂性缺血性扩张的自动测量是一种临床有用的标志物，对检测严重广泛冠状动脉疾病敏感且高度特异。
