Objective: To investigate the relations of carotid plaque characteristics of MRI and clinical factors with ischemic stroke in patients with carotid artery stenosis≤50%.
Methods: From September 2014 to February 2016, a total of 43 patients with carotid artery stenosis ≤50% were selected by ultrasound screening. All patients underwent the black-blood MRI examination. The relations of the plaque MRI characteristics and other risk factors with ischemic stroke were analyzed.
Results: In the 43 patients, the degree of carotid artery stenosis ranged from 5% to 50%, and the follow-up time ranged from 1.9 to 19.4 months. During the follow-up period, ipsilateral ischemic stroke occurred in 4 patients. The results of univariate and multivariate Logistic regression analysis showed that only the intra-plaque hemorrhage (IPH) was significantly associated with ischemic stroke (OR=297.797, 95% CI=2.638–33620, P=0.018), while other MRI features and clinical factors were irrelevant to ischemic stroke (all P>0.05). Kaplan-Meier survival analysis showed that the mean ischemic stroke-free time in patients with IPH was significantly shorter than that in patients without IPH (14.3 months vs. 18.6 months, P=0.001), and in patients with coronary heart disease (CHD) was significantly shorter than that in patients without CHD (12.1 months vs. 18.7 months, P=0.029); Cox regression analysis showed that IPH (HR=18.2, 95% CI=2.7–123.3, P=0.003) and CHD (HR=27.4; 95% CI=1.6–464.3; P=0.022) were independent risk factors for ischemic stroke.
Conclusion: In patients with carotid artery stenosis ≤50%, IPH and CHD are closely associated with the occurrence of ischemic stroke.