PURPOSE 18F-sodium fluoride (18F-NaF) has shown promise in assessing disease activity in coronary arteries, but currently used measures of activity - such as maximum target to background ratio (TBRmax) - are defined by single pixel count values. We aimed to develop a novel coronary-specific measure of 18F-NaF PET reflecting activity throughout the entire coronary vasculature (coronary microcalcification activity [CMA]). METHODS Patients with recent myocardial infarction and multi-vessel coronary artery disease underwent 18F-NaF PET and coronary CT angiography. We assessed the association between coronary 18F-NaF uptake (both TBRmax and CMA) and coronary artery calcium scores (CACS) as well as low attenuation plaque (LAP, attenuation < 30 Hounsfield units) volume. RESULTS In 50 patients (64% males, 63 ± 7 years), CMA and TBRmax were higher in vessels with LAP compared to those without LAP (1.09 [0.02, 2.34] versus 0.0 [0.0, 0.0], p < 0.001 and 1.23 [1.16, 1.37] versus 1.04 [0.93, 1.11], p < 0.001). Compared to a TBRmax threshold of 1.25, CMA > 0 had a higher diagnostic accuracy for detection of LAP: sensitivity of 93.1 (83.3-98.1)% versus 58.6 (44.9-71.4)% and a specificity of 95.7 (88.0-99.1)% versus 80.0 (68.7-88.6)% (both p < 0.001). 18F-NaF uptake assessed by CMA correlated more closely with LAP (r = 0.86, p < 0.001) than the CT calcium score (r = 0.39, p < 0.001), with these associations outperforming those observed for TBRmax values (LAP r = 0.63, p < 0.001; CT calcium score r = 0.30, p < 0.001). CONCLUSIONS Automated assessment of disease activity across the entire coronary vasculature is feasible using 18F-NaF CMA, providing a single measurement that has closer agreement with CT markers of plaque vulnerability than more traditional measures of plaque activity.

中文翻译：

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全血管冠状动脉 18F-氟化钠 PET 用于评估整体冠状动脉微钙化负担。


目的 18F-氟化钠 (18F-NaF) 在评估冠状动脉疾病活动方面显示出前景，但目前使用的活动测量方法 - 例如最大目标与背景比 (TBRmax) - 是由单像素计数值定义的。我们的目标是开发一种新的 18F-NaF PET 冠状动脉特异性测量方法，反映整个冠状动脉血管系统的活动（冠状动脉微钙化活动 [CMA]）。方法 对近期发生心肌梗死和多支冠状动脉疾病的患者进行 18F-NaF PET 和冠状动脉 CT 血管造影。我们评估了冠状动脉 18F-NaF 摄取（TBRmax 和 CMA）与冠状动脉钙评分 (CACS) 以及低衰减斑块（LAP，衰减< 30 Hounsfield 单位）体积之间的关联。结果 在 50 名患者（64% 男性，63 ± 7 岁）中，与无 LAP 的血管相比，有 LAP 的血管的 CMA 和 TBRmax 较高（1.09 [0.02, 2.34] 对比 0.0 [0.0, 0.0]，p < 0.001 和 1.23 [1.16, 1.37] 与 1.04 [0.93, 1.11]，p < 0.001）。与 TBRmax 阈值 1.25 相比，CMA > 0 检测 LAP 的诊断准确性更高：敏感性为 93.1 (83.3-98.1)% vs 58.6 (44.9-71.4)%，特异性为 95.7 (88.0-99.1)%对比 80.0 (68.7-88.6)%（均为 p < 0.001）。通过 CMA 评估的 18F-NaF 摄取与 LAP 的相关性（r = 0.86，p < 0.001）比 CT 钙评分（r = 0.39，p < 0.001）更密切，这些关联优于 TBRmax 值观察到的关联（LAP r = 0.63，p < 0.001；CT 钙评分 r = 0.30，p < 0.001）。 结论 使用 18F-NaF CMA 对整个冠状动脉血管系统的疾病活动进行自动评估是可行的，与更传统的斑块活动测量相比，它提供了与斑块易损性 CT 标记更接近的单一测量结果。