Higher Plaque Burden of Middle Cerebral Artery Is Associated With Recurrent Ischemic Stroke: A Quantitative Magnetic Resonance Imaging Study.

Background and Purpose- This study aims to investigate the association between the characteristics of atherosclerotic plaques of middle cerebral artery and recurrent ischemic stroke using magnetic resonance vessel wall imaging. Methods- One hundred and five patients with ischemic stroke attributed to middle cerebral artery plaque underwent high-resolution black-blood magnetic resonance vessel wall imaging. They were divided into group 1, with the first episode of acute stroke (imaging within 4 weeks of stroke, n=44); group 2, with recurrent acute stroke (n=29); and group 3, with chronic stroke (imaging after 3 months of stroke, n=32). Plaque characteristics including plaque area, plaque burden, contrast-enhancement ratio, eccentricity, and degree of stenosis were measured and compared across 3 groups. Association between plaque characteristics and recurrent strokes was investigated by multivariate analysis. Results- Plaque burden was significantly greater in recurrent stroke group than the other 2 groups (median: group 2, 82.7%, versus group 1, 76.3%, and group 3, 73.4%; P=0.001). Patients with acute stroke had higher enhancement ratio than patients with chronic stroke (median: group 1, 1.59, and group 2, 1.90, versus group 3, 1.33; P=0.014). Comparing to first-onset acute stroke patients, recurrent stroke patients were older, more likely with female sex and hypertension, and had higher plaque burden. After adjustment of clinical factors, plaque burden was the only independent imaging feature associated with recurrent stroke (odds ratio, 2.26, per 10% increase [95% CI, 1.03-4.96]; P=0.042). Conclusions- Higher plaque burden of middle cerebral artery identified on magnetic resonance vessel wall imaging is independently associated with recurrent ischemic stroke.