Prevalence and Temporal Distribution of Fast and Slow Progressors of Infarct Growth in Large Vessel Occlusion Stroke.

Background and Purpose- Fast and slow progressors of infarct growth due to anterior circulation large vessel occlusion are commonly observed in clinical practice. We aimed to estimate the prevalence and temporal distribution of fast and slow progressors among anterior circulation large vessel occlusion patients diagnosed within 24 hours of stroke onset. Methods- Single-center retrospective study of all patients with anterior circulation large vessel occlusion who underwent baseline computed tomographic perfusion or magnetic resonance imaging within 24 hours of stroke onset. Prevalence was determined for fast progressors (ischemic core >70 mL, <6 hours of stroke onset) and slow progressors (ischemic core ≤30 mL, >6-24 hours of stroke onset). Results- One hundred eighty-five patients were included. The median time interval from stroke onset to baseline core imaging was 7.6 hours (interquartile range, 3.9-13.2), and median core volume was 17 mL (range, 0-405). Patients had core volume ≤70 mL in 72% of cases in the overall cohort. The prevalence of fast progressors was 25% (95% CI, 17%-37%) and reached 40% (95% CI, 24%-59%) between 3 and 4.5 hours after stroke onset. The prevalence of slow progressors was 55% (95% CI, 46%-64%) and was similar across time intervals beyond 6 hours after stroke onset. Conclusions- Most anterior circulation large vessel occlusion patients had small-to-moderate ischemic core volume, irrespective of early or delayed presentation within 24 hours of stroke onset. Fast progressors were highly prevalent between 3 and 4.5 hours after stroke onset.