Abstract WP187: Correlation between Infarct Shape and Volume and Ischemic Risk Factors and Recurrent Ischemic Rates in Small Subcortical Stroke; Data from the SPS3 Randomized Controlled Trial
Background: Most of lacunar infarcts (LI) are due to penetrating small vessel disease, although other mechanisms can be responsible for LI. We sought to determine the relationship between the size and shape of LI and underlying risk factors and recurrent ischemic stroke rates.
Methods: 872 images from the 3020 patients enrolled in the Secondary Prevention of Small Subcortical Strokes (SPS3) trial were included in this analysis. SPS3 is a multi-center randomized trial of MRI proven lacunar stroke patients. Participants with confirmation of their index event by DWI were reviewed. Infarct volume was measured planimetrically, and shape was classified as ovoid/spheroid, slab, stick, or multi-component based on visual analysis after 3D reconstruction of axial MRI slices using OsiriX software.
Results: Infarct shape was ovoid/spheroid in 67%, slab in 10%, stick in 6%, and multi-component in 17% of patients. Median infarct volumes differed by shape with the smallest LI volumes observed in ovoid/spheroid: 0.52, 0.76, 0.62, and 0.93 respectively, p < 0.001. Patients with ovoid/spheroid LI were of similar age (means 61 vs. 62 yr, p = 0.4), sex (57 vs 60%, p=0.5), and hypertension status (81% vs. 80%, p = 0.7), but more likely to be diabetic (43% vs. 32%, p = 0.003) and have IHD (17% vs. 10%, p =0.02) vs. those with other shapes combined. Prevalence of relevant intracranial large vessel occlusion on vascular imaging was 7% in the ovoid/spheroid S3 group and 9% in others (p = 0.5). The 6-year re-current stroke rate was 16.1% with 91 strokes occurring. There was no difference in reinfarction rate based on shape or volume.
Conclusion: Lacunar strokes comprise a heterogeneous group of cerebral infarction likely secondary to variable etiologies. In this preliminary analysis infarct shape was correlated with risk factors but not with stroke infarct. Final analysis will be presented and likely the ongoing SPS3 data analyses will elucidate these differences.
- © 2012 by American Heart Association, Inc.