Clinical Perspective of Carotid Plaque Imaging

At present, patients with carotid disease are selected for invasive recanalization therapies mainly based on the degree of luminal narrowing and the presence or absence of recent ischemic symptoms. A more sophisticated risk model takes into account other clinical variables, such as age, sex, and the type of recent symptoms, as well as presence of ulcerated plaque. A growing body of evidence shows that noninvasive imaging of the carotid plaque by various methods reliably identifies structural correlates of plaque vulnerability, which are associated with an increased risk of cerebrovascular events.

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Integration of plaque imaging at baseline in randomized controlled trials is needed to test the hypothesis that plaque imaging helps select patients who benefit from carotid revascularization. If this holds true, then plaque imaging should be incorporated in management guidelines.

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A meta-regression analysis of data from medical arms of randomized trials and prospective cohorts suggested that the risk of ipsilateral stroke associated with asymptomatic carotid stenosis has declined over the past 20 years and may now be only 1% per year or lower, most likely attributable to advances in medical therapy. Indeed, under modern medical management of atherosclerosis, only a minority of patients with asymptomatic carotid disease may currently benefit from invasive revascularization.

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