Background: Recent studies have used basic epicardial adipose tissue (EAT) assessments (e.g., volume and mean HU) to predict risk of atherosclerosis-related, major adverse cardiovascular events (MACE). Objectives: Create novel, hand-crafted EAT features, 'fat-omics', to capture the pathophysiology of EAT and improve MACE prediction. Methods: We segmented EAT using a previously-validated deep learning method with optional manual correction. We extracted 148 radiomic features (morphological, spatial, and intensity) and used Cox elastic-net for feature reduction and prediction of MACE. Results: Traditional fat features gave marginal prediction (EAT-volume/EAT-mean-HU/ BMI gave C-index 0.53/0.55/0.57, respectively). Significant improvement was obtained with 15 fat-omics features (C-index=0.69, test set). High-risk features included volume-of-voxels-having-elevated-HU-[-50, -30-HU] and HU-negative-skewness, both of which assess high HU, which as been implicated in fat inflammation. Other high-risk features include kurtosis-of-EAT-thickness, reflecting the heterogeneity of thicknesses, and EAT-volume-in-the-top-25%-of-the-heart, emphasizing adipose near the proximal coronary arteries. Kaplan-Meyer plots of Cox-identified, high- and low-risk patients were well separated with the median of the fat-omics risk, while high-risk group having HR 2.4 times that of the low-risk group (P<0.001). Conclusion: Preliminary findings indicate an opportunity to use more finely tuned, explainable assessments on EAT for improved cardiovascular risk prediction.
翻译:背景:近期研究使用基础的心外膜脂肪组织(EAT)评估指标(如体积和平均HU值)预测动脉粥样硬化相关主要不良心血管事件(MACE)的风险。目的:构建新型手工设计的EAT特征"脂肪组学",以捕捉EAT的病理生理学特征并提升MACE预测能力。方法:采用前期验证的深度学习算法(可选人工校正)分割EAT区域。提取148项影像组学特征(形态学、空间分布及强度特征),使用Cox弹性网络进行特征筛选与MACE预测。结果:传统脂肪特征预测效果有限(EAT体积/EAT平均HU/BMI的C指数分别为0.53/0.55/0.57)。基于15项脂肪组学特征后获得显著提升(测试集C指数=0.69)。高风险特征包括高HU值体素体积(-50至-30 HU区间)和负偏态HU值——两者均评估与脂肪炎症相关的高HU值。其他高风险特征包括EAT厚度峰度(反映厚度异质性)及心脏顶部25%区域的EAT体积(强调近端冠状动脉周围脂肪)。基于Cox模型识别的中位脂肪组学风险值,能够明确区分高低风险患者的Kaplan-Meyer曲线,高风险组风险比(HR)是低风险组的2.4倍(P<0.001)。结论:初步研究表明,采用更精细化的可解释性EAT评估方法可改善心血管风险预测。