Predictive Outcome of Late Window Ischemic Stroke Patients Following Endovascular Therapy: A Multi-Center Study

Sijie Zhou ¹ Mohammad Mofatteh ^2,3 Zhikai Chen ^1,4 Jinyan Tang ⁴ Jicai Ma ⁵ Ouyang Ziqi ⁶ Jian Wang ⁶ Senrong Luo ¹ Yuankang He ¹ Zhenzhang Li ^7,8 Yuzheng Lai ⁹ Xuxing Liao ^1*

• ¹ First People's Hospital of Foshan, Foshan, Guangdong Province, China
• ² Queen's University Belfast, Belfast, United Kingdom
• ³ Neuro International Collaboration (NIC), London, United Kingdom, London, United Kingdom
• ⁴ Guangdong Medical University, Zhanjiang, Guangdong, China
• ⁵ The Affiliated Yuebei People’s Hospital of Shantou University Medical College, Shaoguan, China, Shaoguan, China
• ⁶ Foshan Sanshui District People’s Hospital, Foshan, Guangdong Province, China
• ⁷ Guangdong Polytechnic Normal University, Guangzhou, Guangdong, China
• ⁸ Guangzhou Medical University, Guangzhou, Guangdong Province, China
• ⁹ Guangdong Provincial Hospital of Integrated Traditional Chinese and Western Medicine, Foshan, Guangdong Province, China

Background and purpose: Stroke is a leading cause of morbidity and mortality worldwide. Endovascular therapy (EVT) has been established as a gold standard option to treat acute ischemic stroke (AIS) patients with large vessel occlusion (LVO) presenting within 6 hours of symptom onset. However, there is a paucity of information regarding patient outcome and mortality in patients presenting in late time window within 6 to 24 hours. In this study, we aimed to assess for predictors of outcomes in late window stroke patients following EVT.We analyzed data from 202 patients treated with EVT from four comprehensive stroke centers. All patients were above 18 years of age and had symptoms onset of 6-24 hours. mRS of 0-2 after three months was defined as favorable outcome.Results: Patients with favorable outcome had lower median age (p= 0.003), lower pre-EVT National Institute of Health Stroke Scale (NIHSS) score (p= 0.000), lower diabetes mellitus (p= 0.041), stroke history (p= 0.041), parenchymal hematoma (PH) (p= 0.000) and fewer attempts to achieve successful recanalization (p= 0.001). Multivariate regression analysis found age (p= 0.007), diabetes mellitus (p= 0.022), successful recanalization (mTICI≥ 2b) (p= 0.006), NIHSS at onset (p= 0.000), and PH1+PH2 Heidelberg bleeding classification (p= 0.009) as predictors of functional outcome.Age, diabetes mellitus history, baseline NIHSS score, successful recanalization, and PH are predictors of 90-day functional outcome of late-window ischemic stroke patients undergoing EVT.