Background and Objectives: Cardiac computed tomography angiography (CCTA) is an excellent non-invasive imaging tool to evaluate coronary arteries and exclude coronary artery disease (CAD). Managing intermediate coronary artery stenosis with negative or inconclusive functional tests is still a challenge. A regular stenosis evaluation together with high-risk plaque features, using semi-automated programs, are becoming promising tools. This case–control study was designed to evaluate the intermediate lesion features’ impact on CAD outcomes, using a semi-automated CCTA atherosclerotic plaque analysis program. Materials and Methods: We performed a single-center, prospective cohort study. A total of 133 patients with low to intermediate risk of CAD, older than 18 years with no previous history of CAD and good quality CCTA images were included in the study, and 194 intermediate stenosis (CAD-RADS 3) were analyzed. For more detailed morphological analysis, we used semi-automated CCTA-dedicated software. Enrolled patients were prospectively followed-up for 2 years. Results: Agatston score was significantly higher in the major adverse cardiovascular events (MACE) group (p = 0.025). Obstruction site analysis showed a significantly lower coronary artery remodeling index (RI) among patients with MACE (p = 0.037); nonetheless RI was negative in both groups. Plaque consistency analysis showed significantly bigger necrotic core area in the MACE group (p = 0.049). In addition, unadjusted multivariate analysis confirmed Agatston score and RI as significant MACE predictors. Conclusions: The Agatston score showes the total area of calcium deposits and higher values are linked to MACE. Higher plaque content of necrotic component is also associated with MACE. Additionally, negatively remodeled plaques are linked to MACE and could be a sign of advanced CAD. The Agatston score and RI are significant in risk stratification for the development of MACE.

Funding Acknowledgements Type of funding sources: None. Introduction With advances in coronary computed tomography angiography (CTA) technology dedicated semi-automated coronary plaque analysis software become researches field of interest. With detailed plaque analysis we can improve CTA diagnostic accuracy and prognostic value, this way improving chronic coronary syndrome (CCS) outcomes. Purpose The aim of this study was to evaluate well known modifiable coronary risk factors (arterial hypertension (AH), smoking, diabetes mellitus (DM), hypercholesterolemia, physical inactivity, obesity) and statin use in relation to more detailed plaque features. Methods 100 patients with stable angina and no previous history of CCS underwent CTA and were diagnosed with one or more intermediate stenosis (correspond to 50-69% stenosis). A total of 112 stenosis were analysed with post-processing semi-automated CTA dedicated software. This is a sub-study from a bigger trial, where intermediate lesions were analysed.  Results Overall all lesions were analyzed as whole and at the vessel cross-section of maximum obstruction site. 45 different parameters were obtained. Analysis made at the level of whole lesion showed that smokers had lower plaque and dense calcium volumes (Table 1), statin users lower fibrous fatty and necrotic core volumes (Table 2). Obstruction area analysis showed significant larger vessel wall area and diameter in non-smokers group (Table 1), whereas statin users had smaller lumen area and diameter stenosis (Table 2). Patients with DM had bigger necrotic core volume with significant bigger fibrous fatty and necrotic core percentages (Table 3). AH, hypercholesterolemia, physical inactivity or obesity did not show any significant relation with plaque features (p≥0.05). Renal insufficiency was excluded as a risk factor as all patients referred to CTA had normal or slightly decreased renal function (GFR >60 ml/min.). Conclusion Our study shows that modifiable risk factors (smoking and DM) alongside with statin use are related to quantitative atherosclerotic plaque parameters. For risk factors modification impact on plaque characteristics studies should be done. Abstract Table 1; 2; 3.