ABSTRACT NUMBER: ESOC2026A500 ASSOCIATIONS OF COMPUTED TOMOGRAPHY ANGIOGRAPHY-BASED PLAQUE-RADS SUBTYPES WITH SYMPTOMATIC CAROTID ATHEROSCLEROSIS

Abstract Background and aims Carotid Plaque-RADS (Plaque Reporting and Data System) scoring offers a reproducible framework to characterize internal carotid artery (ICA) plaque morphology across imaging modalities. This study investigated associations between Computed Tomography Angiography (CTA)-based Plaque-RADS subgroups and recurrent vascular events in patients with non-cardioembolic stroke/TIA. Methods Baseline CTAs from 517 patients in the CONVINCE (Colchicine for prevention of vascular inflammation in Non-CardioEmbolic stroke) trial were analyzed. Plaque-RADS scoring assigned ICA’s to the following subgroups: (1) no plaque, (2) plaque thickness < 3 mm, (3a) thickness ≥ 3 mm, (3c) ulceration, (4a) intraplaque hemorrhage, and (4c) intraluminal thrombus. In ICA’s ipsilateral to the index ischaemic lesion, Cox proportional hazards models were used to assess associations with subsequent ipsilateral ischaemic stroke, any stroke/TIA, and major adverse cardiovascular events (MACE), using both ordinal (per-level increase) and binary (RADS < 3 vs ≥3) classifications. Results Available data from 510 patients (median age 67.0 years, 27.8% female, 966 ICA’s were analyzed. Among 321 ICA’s (33.2%) ipsilateral to the index event, recurrent ipsilateral stroke occurred in 12 (3.7%), any stroke/TIA in 32 (10.0%), and MACE in 37 patients (11.5%) during a median follow-up of 35.7 months. Per-level increases in Plaque-RADS scores were associated with an increased risk of ipsilateral stroke (HR 1.48, 95%CI 1.07-2.05) and any stroke/TIA (HR 1.32, 95%CI 1.08–1.61), but not MACE (Table 1). Binary analyses showed strong associations with all endpoints (Table 2). Conclusions In ICA’s ipsilateral to the index ischaemic lesion, higher Plaque-RADS scores were associated with an increased risk of subsequent vascular events. Conflict of interest Darragh Nerney should also be considered an author. The authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article. Figure 1 - belongs to Methods Table 1 - belongs to Results Table 2 - belongs to Results