ARFI Log(VoA)-Derived Atherosclerotic Plaque Composition In Symptomatic vs Asymptomatic Patients

While carotid plaque composition and structure indicate vulnerability to rupture, few such vulnerable plaques ultimately give rise to strokes. We herein evaluate if in vivo ARFI log(VoA) delineations of plaque morphology differentiate symptomatic plaques, which carry high stroke risk, from those that are asymptomatic and have lower stroke risk. Forty-one carotid plaques in patients with clinical indication for carotid endarterectomy (CEA) to prevent stroke and 26 plaques in patients without indication for CEA were imaged. Among these plaques, 33 were symptomatic and 34 were asymptomatic. When plaques were segmented manually by a blinded reader or automatically by a machine-learning classifier, no there were no statistically significant differences in total plaque area or in percent area of calcium, collagen, necrotic core, or intraplaque hemorrhage between symptomatic and asymptomatic plaques. Further, all plaque features yielded AUC scores <0.6 in ability to distinguish symptomatic from asymptomatic. These findings, which are consistent with expectation, suggest that plaque morphology alone does not precisely predict rupture potential and, thus, additional risk factors, such as wall shear stress, may be required for individualized stroke risk prediction.