Abstract 17535: Carotid Artery Calcifications and High-risk Carotid Plaques Identified by CT Angiograms are Associated With an Increased Predisposition of Ischemic Strokes

Introduction: Ischemic strokes account for nearly 90% of all strokes in the United States. Non-invasive computed tomographic angiograms (CTA) are performed routinely in patients with stroke-like symptoms. While the severity of carotid stenosis is conventionally used to plan medical therapy or interventions, there is no data to predict the future risk of ischemic strokes based on additional high-risk characteristics that can be visualized by modern CTA. Methods: We examined the head and neck CTA of 485 patients who presented to our tertiary stroke center with symptoms suggestive of transient ischemic attacks or stroke. Using the post-processed CT images, we analyzed the severity of stenosis and plaque characteristics of the common, internal and external carotid arteries, and also evaluated for evidence of ischemic strokes. Carotid lesions were defined in terms of the degree of stenosis, calcifications (speckled or eccentric), presence of non-calcified plaques, positive remodeling, and presence of a Napkin-Ring Sign. Results: Of the 485 patients, 278 were males (mean age: 67 years), with 109 having a history of stroke. Our data showed that patients with unilateral or bilateral high-risk soft plaques and carotid calcifications visualized by CTA were associated with increased risk of ischemic cerebral events (p<0.001). Additionally, we found that patients with stroke had a greater number of calcium speckles (6-speckles in stroke group vs 4-speckles in non-stroke group; P<0.01) in their carotid arteries. Receiver-Operating Curve analysis showed that the presence of more than 2 speckles in the carotid arteries portends a higher likelihood of developing a stroke (P<0.01). Conclusions: This novel study shows that the presence of carotid artery calcifications or non-calcified high-risk soft plaques on one or both carotid arteries, in addition to >2 calcium speckles in the carotid arteries were associated with an ischemic stroke. These results emphasize that the nature of atherosclerosis, and utility of comprehensive non-invasive CTA to identify patients who are at higher risk of developing ischemic stroke with a goal of early therapeutic strategies.