Surface-based cortical morphometry, white matter hyperintensity, and multidomain cognitive performance in asymptomatic carotid stenosis

Rationale For patients with asymptomatic high-grade carotid stenosis, clinical investigations have focused on preventing cerebral infarction, yet stenosis that reduces cerebral blood flow may independently impair cognition. Whether revascularization of a hemodynamically significant carotid stenosis can alter the course of cognitive decline has never been investigated in the context of a randomized clinical trial. Hypothesis Among patients randomized in the Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis (CREST-2) trials, the magnitude of treatment differences (revascularization versus medical management alone) with regard to cognition will differ between those with flow impairment compared to those without flow impairment. Sample size We will enroll approximately 500 patients from CREST-2, of which we anticipate 100 will have hemodynamic impairment. We estimate 93% power to detect a clinically meaningful treatment difference of 0.5 SD. Methods and design We will use perfusion-weighted magnetic resonance imaging to stratify by hemodynamic status. Linear regression will compare treatment differences, controlling for baseline cognitive status, age, depression, prior cerebral infarcts, silent infarction, white matter hyperintensity volume, and cerebral microbleeds. Study outcomes The primary outcome is change in cognition at one year. Secondary outcomes include silent infarction, change in white matter hyperintensity volume, number of cerebral microbleeds, and cortical thickness over one year. Discussion If cognitive impairment can be shown to be reversible by revascularization, then we can redefine “symptomatic carotid stenosis” to include cognitive impairment and identify a new population of patients likely to benefit from revascularization. Trial Registration US National Institutes of Health (NIH) clinicaltrials.gov NCT03121209

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Abstract 212: Factors Associated with Symptom Development in Asymptomatic Carotid Artery Stenosis: Multimodal Carotid and Perfusion Imaging Study

Stroke ◽

10.1161/str.46.suppl_1.212 ◽

2015 ◽

Vol 46 (suppl_1) ◽

Author(s):

Soonwook Kwon ◽

Mi Ji Lee ◽

Keon-Ha Kim ◽

Pyoung Jeon ◽

Young-wook Kim ◽

...

Keyword(s):

White Matter ◽

Carotid Stenosis ◽

White Matter Hyperintensity ◽

Symptom Development ◽

Asymptomatic Carotid Stenosis ◽

Asymptomatic Carotid ◽

Deep White Matter ◽

Symptomatic Carotid ◽

Factors Associated ◽

Symptomatic Carotid Stenosis

Background: The predictors of symptom development in asymptomatic carotid stenosis are still unclear. We sought to identify factors associated with symptom development in asymptomatic carotid stenosis using multimodal imaging technique. Methods: We retrospectively collected patients who had carotid artery revascularization procedures (carotid endarterectomy [CEA] or carotid artery stenting [CAS]) from April 2007 to May 2013. Patients who had event of cerebral ischemic stroke during 6 months before CEA or CAS were categorized as a symptomatic carotid stenosis. Results from carotid Duplex sonography, CT angiography, brain MRI and MRA, perfusion-weighted MRI (PWI), and demographic profiles were compared. Multivariate logistic regression analysis was performed to identify factors associated with symptom carotid stenosis. Results: A total of 684 patients (asymptomatic 58%, symptomatic 42%) with carotid stenosis more than 50% were included. The presence of ischemic heart diseases, peripheral artery occlusive disease and use of statin were higher in the asymptomatic carotid stenosis. On Duplex scan, ulceration, echolucent plaque, and heterogeneous components of plaque were more frequent in symptomatic carotid stenosis. Angiographic data showed the length of plaque was longer in symptomatic carotid stenosis. Presence of deep white matter hyperintensity, FLAIR vessel sign and GRE vessel sign were more frequently observed in symptomatic carotid stenosis. Patients with symptomatic carotid stenosis had increased cerebral blood flow, cerebral blood volume (CBV), and delayed time to peak when compared to the asymptomatic stenosis. Multivariate analysis revealed length of plaque (>20mm), deep white matter hyperintensity and increased CBV were associated with symptomatic carotid stenosis (Odd ratio [OR]=2.339, 95% confidence interval [CI] 1.312-4.169, P=0.004; OR=2.315, 95% CI 1.160-4.619, P=0.017; OR=2.242, 95% CI 1.127-4.463, P=0.021, respectively). Conclusion: Plaque burden, deep white matter hyperintensity, and increased CBV were independent predictors of symptom development in carotid stenosis. Multimodal imaging may be useful to identify high risk patients of ischemic stroke among asymptomatic carotid stenosis.

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