Carotid plaque stability in patients with symptomatic carotid stenosis: a study of high-resolution magnetic resonance imaging

Abstract

Objective To investigate the value of high-resolution magnetic resonance imaging (HR-MRI) for assessing the plaque stability as well as the risk factors for unstable plaque and severe stenosis in patients with symptomatic carotid stenosis. Methods The patients with symptomatic carotid stenosis were enrolled. HR-MRI was use to evaluate carotid plaque compositions and identify the stability of plaques. The carotid plaques from the patients underwent carotid endarterectomy were collected for pathological examination. The consistency of the preoperative HR-MRI and the postoperative pathological findings were compared. The clinical data of all patients were collected and the risk factors for the stability of carotid plaques and the severity of vascular stenosis were analyzed. Results A total of 219 patients with symptomatic carotid stenosis (stenosis >50%) who underwent HR-MRI were enrolled. Among them, 102 patients (46.6%) had stable plaques and 117 (53.4%) had unstable plaques; 118 (53.9%) had moderate stenosis and 101 (46.1%) had severe stenosis. Thirty-five patients received carotid endarterectomy, HR-MRI showed that the plaque in 19 (54.3%) of them were instable, and pathological examination showed that the plaque in 20 (57.1%) cases were instable, and both were highly consistent (κ=0.942, P<0.001). The proportions of male (P=0.007), hyperlipidemia (P=0.013), smoking (P<0.001), as well as the levels of total cholesterol (P=0.001), low-density lipoprotein cholesterol (P<0.01), and fasting blood glucose (P=0.001) in the unstable plaque group were significantly higher than those in stable plaque group. Multivariate logistic regression analysis showed that male (odds ratio [OR] 2.33, 95% confidence interval [CI] 1.08-5.04; P=0.032), smoking (OR 3.45, 95% CI 1.67-7.14; P=0.001), and higher fasting blood glucose level (OR 1.26, 95% CI 1.07-1.48; P=0.006) were the independent risk factors for unstable plaque. All the data did not show any significant difference between the moderate stenosis group and the severe stenosis group. Conclusions HR-MRI accurately assessed the plaque stability in patients with symptomatic carotid stenosis. Sex, smoking, and fasting blood glucose level were the independent risk factors for carotid artery unstable plaque. Key words: Carotid Artery Diseases; Plaque, Atherosclerotic; Carotid Stenosis; Magnetic Resonance Imaging; Risk Factors