Correlation study of coronary plaque quantitative analysis and myocardial ischemic injury based on coronary CT angiography

Objective To analyze the quantitative features of coronary plaque and evaluate its diagnostic performance for myocardial ischemic injury in patient with coronary artery disease. Methods Retrospectively enrolled 109 patients with suspected coronary artery disease, who successively underwent coronary CT angiography(CCTA) and coronary angiography in Shandong Provincial Hospital from June 2018 to September 2019. Elevated myocardial enzyme with segmental wall motion abnormalities (SWMA) in ultrasound was defined as myocardial ischemic injury, with which the subjects were divided into two groups, with and without myocardial ischemic injury (n=75,34) respectively. CCTA images of each target vessel were quantitatively analyzed by automated plaque analysis software to obtain the following indexes: minimal lumen area(MLA), plaque length(PL), total plaque volume(TPV), total plaque burden(TPB),calcified plaque volume(CPV), calcified plaque ratio(CPR), fibrous plaque volume(FPV), fibrous plaque ratio(FPR), lipid plaque volume(LPV), lipid plaque ratio(LPR), napkin-ring sign(NRS), spotty calcification(SC), remodeling index (RI) and eccentric index (EI). Chi-square, Mann-Whitney U tests, logistic regression and area under the receiver operating characteristics were determined. Results For the degree of coronary artery stenosis, MAS% was 85.00% (80.00%, 92.00%) and 63.00% (60.00%, 65.00%) in myocardial ischemic group and without myocardial ischemic injury group, which was statistically significant (Z=-4.32, P=0.001). For the quantitative plaque features, TPV 150.13 (104.44,202.20) mm3, TPB (75.67%±9.90%), FPV 95.73 (66.57, 134.23)mm3, LPV 32.18 (18.93,54.55) mm3, LPR (25.13%±13.71%) in the group with myocardial ischemic injury were larger than those in group without myocardial ischemic injury 109.94 (79.39, 121.67) mm3, 65.37%±6.94%, 67.35 (57.67, 90.11) mm3, 16.64 (13.26, 24.73) mm3, 18.44%±7.09% respectively with statistically significant (Z=-2.59, P=0.010; t=3.11, P=0.003; Z=-2.16, P=0.031; Z=-2.18, P=0.029; t=2.19, P=0.037). In logistic regression analysis, MAS%(OR=1.55,P=0.021) was independent significant predictors of myocardial ischemic injury. The AUC of MAS%, LPV, LPR, TPV, TPB, FPV were 0.84, 0.82, 0.77, 0.72, 0.74, 0.67, respectively, which were all statistically significant (P<0.05). Conclusions In quantitative plaque analysis by coronary CT angiography, MAS%, TPV, TPB, FPV, LPV, LPR were affecting factors of myocardial ischemic injury, in which MAS% was independent predictors. MAS% and LPV have higher diagnostic accuracy in myocardial ischemic injury. Key words: Coronary disease; Myocardial ischemia; Tomography, X-ray computed