Impact of cerebral collateral recycle status on clinical outcomes in elderly patients with endovascular stroke treatment

Elderly patients are at high risk of acute ischemic stroke caused by large vessel occlusion (AIS-LVO) and usually suffer disability and fatality from stroke even after receiving endovascular treatment (EVT). Previous studies lacked the knowledge of comprehensive cerebral collateral for elderly patients. Hence, we explore the role of cerebral collateral recycle (CCR) status in clinical outcomes in a real-world setting among elderly AIS-LVO patients undergoing EVT. This was a multicenter retrospective cohort study. Computed tomographic angiography (CTA) at admission was applied to evaluate cerebral venous outflow profiles by the Cortical Vein Opacification Score (COVES) and pial arterial collaterals by the Tan scale. According to the status of cerebral collaterals, enrolled patients were divided into the poor, moderate, and favorable CCR groups. The primary outcome was functional independence (90-day modified Rankin Scale score 0–2). Among 860 AIS-LVO patients receiving EVT, a total of 338 elderly patients were included in the present study after strict screening. Compared with the poor CCR group, the moderate CCR group (31.1 % vs. 10.2 %; adjusted odds ratio[aOR] 3.80; 95 % confidence interval[CI] 1.71–8.44; P = 0.001) and the favorable CCR group (63.3 % vs. 10.2 %; aOR 8.49; 95 % CI 4.02–17.92; P < 0.001) both had a significantly higher rate of functional independence. In subgroup analysis, similar results were found in AIS-LVO patients with older age, large core infarction, or late time window. The cerebral collateral status in elderly patients with AIS-LVO treated by EVT is a strong predictor of functional outcomes and more robust CCR means better outcomes.