冠状动脉周围脂肪密度指数与斑块参数及血流储备分数关系分析

Association of coronary perivascular fat attenuation index,the parameters of plaque and fractional flow reserve

目的探讨冠状动脉斑块周围脂肪密度指数(FAI)与血流储备分数(FFR)及斑块参数间的关系。方法回顾性收集2015年5月至2019年1月东部战区总医院放射科及上海市第六人民医院放射科113例稳定型冠心病患者(共141个斑块)的资料,其中男78例,女35例,年龄40~83(63±9)岁。所有患者均接受冠状动脉CT血管成像(CCTA)和有创FFR检查。测量斑块及管腔的定量指标(如斑块长度、体积)和定性指标(如斑块性质、高危斑块)以及斑块周围的脂肪密度指数。以斑块周围是否FAI≥-70 HU,将患者和斑块分为FAI阳性组(47例,56个斑块)与FAI阴性组(66例,85个斑块)。分析比较两组间年龄、斑块长度和体积、最小管腔面积(MLA)、CCTA狭窄程度等参数,以及斑块类型、高危斑块数量和特征、心肌缺血(即FFR<0.75)的例数和斑块数。采用logistic回归模型分析心肌缺血与年龄、斑块长度、MLA、FAI等指标之间的关系。采用受试者工作特征曲线比较各指标对心肌缺血的诊断效能。结果 FAI阳性组最小管腔面积较FAI阴性组显著减小[(2.00±1.33)mm2比(4.13±2.41)mm2,P<0.001]。FAI阳性组心肌缺血的病例比例和血管比例高于FAI阴性组(21.3%比4.5%;23.2%比8.2%)(均P<0.05),高危斑块所占比例差异无统计学意义(21.2%比16.1%,P=0.451)。FAI对预测心肌缺血具有一定价值[曲线下面积(AUC)=0.666,P=0.021],且具有增量价值(0.915比0.951,P= 0.033)。结论 FAI较高者MLA更小,心肌缺血的发生率更高,同时FAI对心肌缺血具有一定的预测效能和增量价值。

Objective To explore the association of coronary perivascular fat attenuation index(FAI),the parameters of plaque and fractional flow reserve(FFR).Methods A total of 113 patients(with 141 plaques)(78 males and 35 females,age from 40 to 83 years)with stable coronary artery disease were retrospectively collected from Jingling Hospital and Shanghai Sixth People′s Hospital.All the patients underwent coronary CT angiography and invasive FFR examinations.The quantitative and qualitative parameters of plaque and vessel(such as the length and volume of plaque,the characteristics of plaque and high-risk plaque)and the FAI around the plaque were measured.The patients were divided into positive FAI group(n=46)and negative FAI group(n=66)according to the standard of whether the threshold of FAI≥-70 HU.The quantitative indexes,including age,the length and volume of plaque,minimal lumen area(MLA)and FAI,as well as the qualitative indexed,including the characteristics of plaque,the number and characteristic of high-risk plaque and the number of patients and plaque with positive FFR were compared between the two groups.Further,logistic regression analysis was performed to analyze the correlation among myocardial ischemia,age,the length of plaque,minimal lumen area(MLA),FAI and so on.ROC curve was used for evaluating the performance of each parameter.Results Compared to the negative FAI group,positive FAI group had lower MLA(2.00±1.33 mm2 vs 4.13±2.41 mm2,P<0.001).The proportion of patients and vessels with FFR<0.75 in positive FAI group were significantly higher than that in negative FAI group(21.3%vs 4.5%,P=0.006;23.2%vs 8.2%,P=0.016).The FAI between high-risk plaque and non-high-risk plaque had no significant difference(21.2%vs 16.1%,P=0.451).FAI predicted myocardial ischemia(AUC=0.666,P=0.021)and significantly improved the prediction efficiency of complex model(0.915 vs 0.951,P=0.033).Conclusion Lower MLA and higher incidence of myocardial ischemia were associated with patients with higher FAI.In addition,FAI has a certain prediction efficiency and can provide incremental value for the determination of myocardial ischemia.