Abstract Number: Esoc2026a1432 Carotid Perivascular Fat Attenuation on Ct Angiography as an Imaging Biomarker for Inflammation in Carotid Atherosclerosis: A Systematic Review and Meta-Analysis

Abstract Background and aims Carotid atherosclerosis is a leading cause of ischemic stroke, driven by plaque inflammation. While current carotid imaging focuses on luminal stenosis, quantitative perivascular adipose tissue attenuation (PVAT) on computed tomography angiography has emerged as a potential non-invasive biomarker for arterial inflammation and plaque instability in coronary arteries. This systematic review and meta-analysis consider the utility of PVAT for imaging and risk-stratifying inflamed and vulnerable carotid atherosclerotic plaques. Methods Following PRISMA guidelines, 11 studies involving 2,123 patients were identified. Mean differences (MD) in PVAT between symptomatic and asymptomatic carotid arteries were compared using a random-effects meta-analysis. We also assessed publication bias via Egger’s test and conducted leave-one-out sensitivity analyses to ensure result robustness. Results Symptomatic arteries demonstrated significantly higher PVAT attenuation compared to asymptomatic arteries (MD = 12.63 HU; 95% CI: 8.39-16.88). Although statistical heterogeneity was high (I2 = 92%), the leave-one-out sensitivity analysis showed no significant change in the overall p-value or substantial shifts in statistical heterogeneity. However, Egger's test (intercept = 7.29, p = 0.044) indicated significant publication bias, necessitating caution in interpretation. Conclusions This meta-analysis provides preliminary evidence suggesting the potential utility of PVAT as an emerging non-invasive imaging marker for inflammation in symptomatic carotid atherosclerosis. Further rigorous, prospective validation is essential to confirm its hypothesised role in clinical risk stratification and to explore its application for monitoring treatment response in anti-inflammatory trials. Conflict of interest Claudia Zeicu: nothing do disclose; Shiv Bhakta: nothing to disclose; Jason Tarkin: nothing to disclose; Jacob Brubert: nothing to disclose; James Rudd: nothing to disclose; Elizabeth Warburton: nothing to disclose; Nicholas Evans: nothing to disclose