Investigation of the effect of statin therapy on atherosclerotic plaque burden and high-risk plaque characteristics using coronary computed tomography angiography

Aim: To evaluate the effect of statin therapy on atherosclerotic plaque volume, plaque burden, high-risk plaque (HRP) features, and lesion-specific pericoronary fat attenuation index (FAI) on serial coronary computed tomography angiography (CCTA). Materials and Methods: In this single-center retrospective study, adult patients who underwent two CCTA examinations ≥12 months apart between January 2020 and September 2025 and had available clinical follow-up were included. Patients were classified as statin users or non-users. Total coronary artery calcium score (CAC), plaque characteristics (length, stenosis severity, CAD-RADS category), HRP features, total plaque volume (TPV), plaque burden (PB), compositional subcomponents (calcified, fibrous, fibro-fatty, low attenuation), and vessel-based percent plaque volume (%PV) were assessed. Lesion-specific FAI values were also analyzed. Results: Seventy-nine patients (80% male; mean age 53.1±9.7 years) and 246 plaques were evaluated. No significant difference was observed between groups regarding changes in CAD-RADS. However, the statin group showed a significantly greater regression in HRP features, in TPV, PB, fibro-fatty and low-attenuation components, and in %PV, compared with non-statin patients. Conversely, progression was observed in calcified and fibrous components and in CAC in the statin group. A significant reduction in lesion-specific FAI was also detected. In multivariable regression analyses, statin therapy remained an independent determinant of these changes after adjustment for potential confounders. Conclusion: Serial CCTA demonstrated that statin therapy slows atherosclerotic progression, reduces plaque burden, promotes remodeling toward a more stable phenotype, and decreases inflammatory activity in pericoronary adipose tissue. These findings support the use of CCTA-based serial assessments as a non-invasive tool to monitor biological response to statin therapy and guide patient-specific clinical decision-making. Keywords: Coronary CT angiography, statin therapy, atherosclerotic plaque burden, high-risk plaque, fat attenuation index, quantitative plaque analysis