Carotid plaque vulnerability and circle of Willis anatomy predict ipsilateral brain infarcts and long-term mortality in carotid endarterectomy patients

Cerebral infarcts in carotid artery disease arise from a complex interplay between plaque vulnerability, extracranial vascular burden, intracranial collateral capacity. Although each of these factors has been studied individually, their combined impact on infarct presence, infarct pattern, and long-term outcomes in real-world carotid endarterectomy (CEA) populations remains insufficiently understood. This study aimed to determine how carotid plaque morphology, bilateral carotid stenosis severity, circle of Willis (CW) anatomy jointly influence ipsilateral brain infarcts and overall mortality. We retrospectively analyzed 1,304 CEA patients using standardized CT and CT angiography to assess plaque features, maximal plaque thickness, carotid stenosis burden (carotid score), detailed CW configuration. Ipsilateral cerebral infarcts were classified as territorial or watershed. Logistic regression was used to determine predictors of infarcts and infarct pattern, Cox proportional-hazards models assessed long-term mortality. Reproducibility of plaque composition and thickness assessment was evaluated in 100 patients using Cohen's kappa and intraclass correlation coefficient. Ipsilateral infarcts were present in 36.7%. Independent predictors included symptomatic status, greater plaque thickness, exulcerated plaques, more advanced bilateral carotid disease (lower carotid score), severely compromised CW. Lower carotid scores predicted watershed infarcts, supporting a hemodynamic mechanism; exulcerated plaques predicted territorial infarcts, consistent with distal embolization. Long-term mortality was independently associated with age, diabetes mellitus, chronic obstructive pulmonary disease, severe chronic kidney disease, the presence of ipsilateral infarcts, type-1 CW anatomy, and calcified plaques. In conclusion, plaque vulnerability, extracranial vascular burden, CW integrity provide complementary, clinically meaningful information on the development and pattern of brain infarcts and on long-term survival after CEA. These findings underscore the importance of comprehensive cerebrovascular imaging for risk stratification and individualized management of carotid artery disease.