Objectives This study sought to evaluate the incremental value of quantifying the extent and severity of myocardial perfusion and ¹⁸F-labeled fluorodeoxyglucose (FDG) abnormalities in predicting adverse outcomes among patients with suspicion for cardiac sarcoidosis (CS).

Background Positron emission tomography (PET) with FDG is a key component of the noninvasive assessment of patients with suspected CS. However, the optimal method for image interpretation has not been defined.

Methods A retrospective analysis was performed of 203 patients who underwent perfusion and FDG-PET imaging to evaluate for CS. Imaging findings were scored by conventional 3-category methods (normal perfusion and metabolism, abnormal perfusion or metabolism, abnormal perfusion and metabolism) and by summed scores using the 17-segment model to represent extent and severity of disease. Heterogeneity of metabolism was quantified using the coefficient of variation (SD divided by the mean) of FDG uptake. Multivariable Cox models were developed to assess associations between imaging findings and adverse events (death, heart transplant, or ventricular arrhythmia requiring defibrillation).

Results The indication for FDG-PET was ventricular arrhythmia in 69 (34%), heart block in 16 (8%), cardiomyopathy in 54 (27%), and other indications in 64 (32%). There were 63 patients who developed adverse events over a mean follow-up of 1.8 years. After robust adjustment, only the summed score in segments with a perfusion–metabolism mismatch and the coefficient of variation were important prognostically (p = 0.029 and p = 0.041, respectively).

Conclusions Quantitative measures of extent and severity of perfusion–metabolism mismatch and coefficient of variation of FDG uptake provide an incremental prognostic advantage in patients undergoing FDG-PET for CS. These results support the use of a more detailed analysis of imaging findings, as is conventional in coronary artery disease.

目的本研究旨在评估量化心肌灌注的程度和严重性以及¹⁸ F标记的氟脱氧葡萄糖（FDG）异常在预测怀疑有心脏结节病（CS）的患者的不良结局方面的增量价值。

背景技术带有FDG的正电子发射断层扫描（PET）是可疑CS患者非侵入性评估的关键组成部分。但是，尚未定义用于图像解释的最佳方法。

方法对203例行灌注和FDG-PET显像的患者进行回顾性分析，以评估其CS。影像学检查结果通过常规的3类方法（正常灌注和代谢，异常灌注或代谢，异常灌注和代谢）进行评分，并使用17段模型对得分进行总计，以代表疾病的程度和严重性。使用FDG摄取的变异系数（SD除以平均值）来定量代谢的异质性。开发了多变量Cox模型以评估影像学发现与不良事件（死亡，心脏移植或需要除颤的室性心律失常）之间的关联。

结果FDG-PET的适应症为心律失常69例（34％），心脏传导阻滞16例（8％），心肌病54例（27％）和其他适应症64例（32％）。平均随访1.8年，有63名患者发生了不良事件。经过稳健的调整后，只有在灌注-代谢不匹配的部分中的总得分和变异系数在预后上很重要（分别为p = 0.029和p = 0.041）。

结论定量测量的程度和严重程度-代谢不匹配和FDG摄取的变异系数为接受CS的FDG-PET患者提供了增加的预后优势。这些结果支持对成像结果进行更详细的分析，就像在冠心病中一样。