Abstract Number: Esoc2026a1163 Impact of Inflammation on Carotid Plaque Progression and Risk of Stroke: Interim Analysis of the Increase Study

Abstract Background and aims The benefit of carotid revascularization in patients with asymptomatic carotid stenosis (ACS) remains uncertain in the absence of additional plaque-vulnerability features. We hypothesized that plaque inflammation assessed by 18F-fluorodeoxyglucose positron-emission tomography (18FDG-PET) is associated with the risk of plaque progression and ipsilateral stroke during the follow-up. Methods Prospective study of adult patients with ACS ≥ 50%-99% in at least one internal carotid artery (diagnosed by carotid-ultrasound; graded and followed-up at 1 and 2 years by CT-angiography using NASCET criteria). Participants underwent carotid 18FDG-PET-CT ≤ 30 days after recruitment. The whole-vessel average of the standardized uptake value (WVa-SUV) of the proximal internal carotid artery was calculated and patients were followed-up for ≥1-year period. We studied the association between WVa-SUV and a composite outcome including plaque progression, defined as an increase of at least one category (moderate 50-69%, severe 70-99%, occlusion 100%) or ipsilateral stroke/TIA. Logistic regression analyses were performed adjusting for baseline stenosis degree. Results We included 56 adult patients (73.2 ± 9.9 years, 23.7% women, median follow-up 21.7 months IQR:15.2-27.3) with 60 ACS (28.3% were 70-99%). Average WVa-SUV was 2.26 g/mL (IQR:1.96-2.56). Five (8.3%) ACS progressed and one (1.67%) patient had ipsilateral stroke. WVa-SUV was higher in these ACS (2.92 g/mL vs 2.23 g/mL, P = 0.005). In logistic regression analysis, WVa-SUV was associated with the risk of progression/stroke (aOR 1.47 per-0.1 g/mL-increase, 95%CI 1.09-1.99). Conclusions In patients with ACS, higher WVa-SUV was associated with plaque progression or ipsilateral stroke risk. The INCREASE study aims to confirm these results in a cohort of 102 patients. Conflict of interest Nothing to disclose.