Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland.
J Nucl Cardiol. 2021 Feb;28(1):263-273. doi: 10.1007/s12350-019-01684-1. Epub 2019 Mar 20.
Positron emission tomography (PET) integrating assessment of perfusion with N-ammonia (NH3) and viability with F-fluorodeoxyglucose (FDG) has high accuracy to identify viable, hibernating myocardium. We tested whether quantification of myocardial blood flow (MBF) and washout (k2) can predict myocardial viability using FDG as standard of reference.
In 180 consecutive patients with ischemic cardiomyopathy, myocardium was categorized on a segment-level into normal, ischemic, hibernating, and scar. From dynamic images, stress MBF, rest MBF, and k2 were derived and myocardial flow reserve (MFR) and volume of distribution (VD) were calculated.
Across myocardial tissues, all parameters differed significantly. The area under the curve (AUC) was 0.564 (95% CI 0.527-0.601), 0.635 (0.599-0.671), 0.553 (0.516-0.591), 0.520 (0.482-0.559), and 0.560 (0.522-0.597) for stress MBF, rest MBF, MFR, k2, and VD. The generalized linear mixed model correctly classified 81% of scar as viable, hibernating myocardium. If the threshold of rest MBF to predict viability was set to 0.45 mL·min·g, sensitivity and specificity were 96% and 12%, respectively.
Quantitative NH3 PET parameters have low to moderate diagnostic performance to predict viability in ischemic cardiomyopathy. However, if rest MBF falls below 0.45 mL·min·g, viability testing by FDG-PET may be safely deferred.
正电子发射断层扫描（PET）结合氨（NH3）灌注评估和氟代脱氧葡萄糖（FDG）存活能力评估，对识别存活、冬眠心肌具有很高的准确性。我们通过 FDG 作为参考标准，测试了血流（MBF）和洗脱（k2）的定量是否可以预测心肌存活能力。
在 180 例连续的缺血性心肌病患者中，心肌在节段水平上分为正常、缺血、冬眠和瘢痕。从动态图像中，得出应激 MBF、静息 MBF 和 k2，并计算心肌血流储备（MFR）和容积分布（VD）。
在所有心肌组织中，所有参数均有显著差异。曲线下面积（AUC）分别为 0.564（95%置信区间 0.527-0.601）、0.635（0.599-0.671）、0.553（0.516-0.591）、0.520（0.482-0.559）和 0.560（0.522-0.597），用于应激 MBF、静息 MBF、MFR、k2 和 VD。广义线性混合模型正确分类了 81%的瘢痕为存活、冬眠心肌。如果将静息 MBF 预测存活的阈值设定为 0.45 mL·min·g，则灵敏度和特异性分别为 96%和 12%。
定量 NH3 PET 参数对缺血性心肌病的存活能力具有低到中等的诊断性能。然而，如果静息 MBF 低于 0.45 mL·min·g，则可以安全地推迟 FDG-PET 进行存活能力检测。
