Objective:We intended to explore the significance that epicardial adipose tissue(EAT)could provide in decision-making on whether the patient should further undergo the coronary angiography when they were suspected of diagnosing coronary artery disease(CAD based on coronary CT angiography(CCTA). We further analyzed the correlation of epicardial adipose tissue volume (EATV)and perivascular adipose tissue thickness(PATT)with the severity of coronary vascular disease-SYNTAX score in patients with coronary atherosclerotic heart disease. We also explored the difference in sensitivity and specificity of EAT combined with clinically relevant indicators compared to the SYNTAX score alone in predicting the prognosis of patients. Methods:Our research involved a total of 81 patients with coronary heart disease who underwent coronary CT angiography(CCTA)and coronary angiography in the First Affiliated Hospital of Nanjing Medical University. The characteristics and treatment of all patients were collected,and EATV,PATT,and SYNTAX scores were calculated based on the patients, imaging data. All patients were followed up six months after discharge,and adverse cardiovascular events,including cardiovascular-related death,myocardial infarction,stent reimplantation, cardiovascular-related disease readmission,stable angina,and unstable angina attacks,were recorded during the follow-up. The logistic regression model was used to analyze the decision -making significance of EATV for further coronary angiography(CAG)in patients with suspected coronary heart disease diagnosed by CCTA. We described the association of EATV with SYNTAX scores using person correlation analysis. We constructed a predictive model for the prognosis of patients with CAD based on EATV and related clinical indicators. Results:①EATV could improve the positive predictive value of clinical intervention after CAG examination in CCTA patients suspected of CAD(AUC rise to 0.771 from 0.562). ② Pearson correlation statistics showed that EATV was positively correlated with SYNTAX score(r=0.828,P<0.001),and the correlation persisted after EAT was standardized for BMI(r=0.774,P< 0.001). ③EATV combined with clinical indicators:gender,LADHU(anterior descending branch adipose tissue Hounsfield unit),and LVDd(left ventricular diastolic diameter)could predict the occurrence of cardiovascular events after discharge(AUC=0.775). The prediction accuracy of this model was higher than that of SYNTAX alone(AUC=0.707). Conclusion:EATV was closely related to CAD and had guiding significance for clinical decision-making of patients with suspected coronary heart disease on CT. It was positively correlated with the SYNTAX score and had predictive relevance for the prognosis evaluation of coronary heart disease.