Rationale and objectives: We sought to test the hypothesis that magnetic resonance imaging (MRI)-defined vulnerable plaques correlate to accelerated reoccurrence of cerebrovascular events and to evaluate the potential use of MRI in secondary prevention of ischemic stroke.
Materials and methods: Fifty-three symptomatic participants were recruited from patients sustaining their second MRI-confirmed cerebral infarction. Nine participants were women and 44 were men; the mean age was 69.2 years (range, 55-94 years). Patients were imaged within 7 days after the reoccurrence of cerebral infarction. The MRI diagnostic signals defined a classification of lesion type. We compare the interval between two cerebral infarctions with plaque vulnerability defined by the MRI lesion type. We used a Cox proportional hazards model to calculate the relationship between vulnerable lesions and the interval of cerebral infarction, and we followed these patients for 180 days and compared the recurrent rate for the third-time cerebral infarction between patients with and without vulnerable plaque.
Results: The mean infarction recurrence interval for patients with vulnerable lesions was shorter than the mean interval for patients without vulnerable lesion (310.1 versus 1697.2, P< .001). In patients with recurrent cerebral infarction within 1 year, vulnerable lesions were more frequently detected (76% versus 19%, P< .001). The patients with vulnerable lesions had an 8.8-fold higher hazard risk (8.8; P< .001, 95% confidence interval, 3.9-19.7) than those without vulnerable lesions after adjustment for risk factors. For those with vulnerable plaque, the morbidity of third-time cerebral infarction was higher than those without (24% versus 3%, P = .023).
Conclusion: MRI-defined vulnerable lesions in carotid arteries are related to accelerated recurrent cerebral infarction and high recurrent rate. MRI demonstrates clinical value in the secondary prevention of cerebral infarction.