The Value Of Coronary Ct Angiography In The Diagnosis Of Vulnerable Plaque Defined By OCT

Background and Purpose:Coronary atherosclerotic heart disease(CHD)has become the leading cause of patient death among diseases worldwide.The pathogenesis of most acute cardiovascular events was related to occlusive thrombosis after the rupture of the thin fibrous cap atherosclerotic plaque(TCFA)covering a large necrotic core.Early identification of vulnerable plaques is critical to save the patient’s life and improve patient survival rates.Optical coherence tomography(OCT)could clearly display the plaque components,However,the complexity and expense operation cannot be widely used.Coronary computed tomographic angiography(CCTA)has become a gatekeeper for coronary heart disease screening with medium and low risk factors due to its advantages of non-invasive.While,few studies focused on the diagnosis value of CCTA plaque characteristics on detecing vulnerable plaques.Pericoronary adipose tissue(PCAT)refers to the local aggregate of adipose tissue surrounding the coronary vascular tree.Recent studies have shown that CCTA can detect inflammatory plaques by CT attenuation index of pericoronary fat(FAI).The FAI of inflammatory infiltrating coronary arteries is different between patients with acute coronary syndrome and stable coronary heart disease,which is valuable for evaluating plaque stability and early inflammation.However,the relevance between FAI and OCT-defined inflammatory infiltrating plaques were rarely explored and reported.This study aims to :(1)evaluating the diagnosis ability of CCTA derived qualitative and quantitative plaque characterics on detecting OCT-defined vulnerable plaques.(2)exploring the relevance between pericoronary fat attenuation index(FAI)and OCT-defined inflammatory infiltrating plaques.MATERIALS AND METHODS:Thirty one patients who underwent both CCTA and OCT were retrospectively enrolled in this study.The quantitative plaque parameters derived from CCTA including calcified and non-calcified(including fibrous and lipid)plaque volume and fraction.Four qualitative plaque characterics including positive remodeling,low-density plaque,punctate calcification,and "napkin ring" sign were also evaluated.Independent Student-t test,Mann-Whitney test and chi-square test were applied for between-group comparsions of CCTA plaque qualitative and quantitative parameters.Univariate and multivariate logistic regression were implemented to build the diagnosic models based on the quantitative and qualitative plaque parameters and explore independent predictors for vulnerable plaques.The receiver operating characteristic(ROC)curve,area under curve(AUC)and confusion matrix were used for diagnosis performance evalutions for established models.Results:A total of 76 plaques in 31 patients were included for analysis,of which 19.7%(15/76 plaques,10 patients)was vulnerable plaques and 15.8%(12/76 plaques,5patients)was inflammatory plaques.Low-density plaques,punctate calcification,positive remodeling,number of high-risk plaque signs,non-calcified fraction and lipid fraction were shown significant differences between vulnerable and non-vulnerable plaques(p < 0.05).The lipid fraction(odd ratio(OR)= 1.148,95% CI0.993 ～ 1.327),punctate calcification(OR = 4.521,95% CI 1.022 ～ 20.008)and low-density plaques(OR = 8.012,95% CI 2.024 ～ 31.718)were independent predictors of vulnerable plaques.Compared with qualitative and quantitative models,the mixed model intergrating all significant CCTA derived plaque characteristics own the highest AUC and accruacy(mixed model AUC = 0.869,95% CI: 0.808 to 0.979;qualitative model AUC = 0.798,95% CI: 0.654 to 0.941;quantitative Model AUC =0.638,95% CI: 0.528～0.866).The FAI of inflammatory infiltrated plaques was significant lower than that of the non-inflammatory infiltrated plaques(p<0.05).Conclusion:The CCTA derived plaque characteristics were able to detecting the OCT-defined vulnerable plaques and the diagnosis performance was enhanced by integrating significant qualitative and quantitative plaque parameters.FAI are significantly different between inflammatory and non-inflammatory infiltrating plaques.