Abstract WMP71: Parent Artery Plaque in Acute Lacunar Stroke: A Prospective, Multicenter, Observational Study

Purpose: We aimed to investigate the prevalence and clinical relevance of the parent artery plaque in acute lacunar stroke. Methods: This prospective, multi-center, observational study included patients with first-ever ischemic stroke within 72 hours of symptom onset. Patients were evaluated by three-dimensional T1-weighted high-resolution magnetic resonance imaging (HR-MRI) and conventional MRI sequences. We examined the presence of intracranial plaque, infarction patterns, and infarct volumes in all the patients with acute lacunar stroke. The outcome measurement was 90-day poor functional outcome (modified Rankin Scale >2). Results: Of the 756 patients included, 341(45.1%) patients had an acute lacunar stroke. There were 201 (58.9%, 201/341) patients with an infarct in deep basal ganglia area. Among them, 64 (31.8%, 64/201) patients had middle cerebral artery (MCA) plaques identified on HR-MRI. The patients with MCA plaque had a similar infarct volume ( 0.93ml vs. 0.88ml , p =0.9) with those without MCA plaque. However, they more likely had an infarct involving posterior limb of internal capsule (42.2%, 27/64 vs. 25.5%, 35/137, p =0.017 ) and had a higher prevalence of cerebral microbleed (68.8%, 44/64 vs. 40.1%, 55/137, p <0.001 ), and moderate to severe perivascular spaces in basal ganglia (BG-PVS)(57.8%, 37/64vs.35.0%, 48/137, p =0.002) . After adjusting for age and National Institute of Health Stroke Scale (NIHSS) at admission, the presence of MCA plaque was independently associated with 90-day poor functional outcome (OR:3.44, [95% CI,1.26-9.42]). There were 102 (29.9%, 102/341) patients with an infarct in pons. Among them, 66 (64.7%, 66/102) patients had basilar artery (BA) plaques. Patients with BA plaque had a higher prevalence of moderate to severe BG-PVS (42.4%, 28/66 vs. 22.2%, 8/36, p =0.041). There were no differences between the patients with and without BA plaque regarding infarction volume and 90-day functional outcome. Conclusions: Parent artery plaque is common in patients with acute lacunar stroke. We propose the deep basal ganglia area infarct with MCA plaque as a unique lacunar stroke subtype with poor prognosis. Our data did not show the presence of BA plaque have an effect on the lacunar stroke prognosis.