Quantitative Study On The Relationship Between Pericoronary Fat And Coronary Plaque Characteristics Based On CCTA

Objective:To investigate the clinical value of pericoronary adipose tissue in evaluating the existence of high-risk plaques.To evaluate the related factors affecting the inflammatory expression of pericoronary adipose tissue.To explore whether the combined diagnosis can improve the diagnostic efficiency of CCTA high-risk plaques.Methods:Patients admitted to the chest pain Center of our hospital from February 2019 to January 2021 were collected and subsequently underwent CCTA+CAG(within 3 months).The results showed that they were all single vessel lesions,and finally 90 cases were included for analysis.91.1%of them were treated with PCI.When there were two or more lesions at the same time for PCI,the narrowest point on the CCTA image was selected for measurement.12.2%of the lesions were confirmed as vulnerable plaques by invasive IVUS examination.During this period,the imaging and clinical data of the patients were collected.The PCAT ratio was calculated as the sum of the thickness of the vertical layer between the coronary artery and the pericardium or between the coronary artery and the surface of the heart at the narrowest lumen of the lesion,divided by the PCAT thickness at the proximal and distal end of the same vessel without plaques.According to the PCAT ratio,the patients were divided into three groups:low,middle,and high.The thickness of EAT and CT values were measured at the thickest layer of epicardial adipose tissue around the middle segment of the three major vessels.Measurement of pericoronary FAI by artificial intelligence software.The data set of coronary artery CTA was analyzed by Vitrea semi-automatic post-processing workstation.The plaque characteristics included total plaque(TP),calcified plaque(CP),non-calcified(NCP),and low,moderate,and high attenuation of non-calcified plaque load,stenosis degree,remodeling index,and so on.Results:There were significant differences in TP,NCP,low attenuation NCP,medium attenuation NCP,RI,and FAI among the PCAT ratio groups(P<0.05).Univariate analysis showed that FAI and PCAT ratio in the high group were significantly correlated with high-risk plaque.When BMI>25kg/m~2,average EAT thickness and CT value were controlled,multivariate logistic regression analysis showed that the ratio of PCAT in the high group was not related to the existence of high-risk plaque(P>0.05),while FAI was still an independent risk factor for high-risk plaque(P<0.001).The results of multivariate analysis showed that the ratio of PCAT in the high group was an independent correlation factor for perivascular FAI≥-70.1HU(P<0.05),while the average EAT thickness and CT value was not related to the increase of FAI.The receiver operating characteristic curve showed that when FAI combined with low attenuation NCP+RI,the maximum area under the curve(AUC)was 0.833(95%:0.746-0.920),the best cutoff value was 0.6527,the sensitivity was 78.2%,and the specificity was 91.3%.Conclusion:(1)After controlling BMI>25kg/m~2,average EAT thickness and CT value,pericoronary FAI value is still an independent risk factor for CCTA high-risk plaque,suggesting that FAI value may be a sensitive index for the evaluation of high-risk plaque.(2)The ratio of PCAT in high group was significantly correlated with FAI≥-70.1HU(inflammatory presence),while the average EAT thickness and CT value were not related to the increase of FAI,which further emphasized the unique biological function of PCAT.(3)FAI value combined with low attenuation NCP and RI is helpful to improve the diagnostic efficiency of CCTA high-risk plaques,which is worthy of rational clinical application.