Endovascular Recanalization and Standard Medical Management for Symptomatic Non-acute Intracranial Artery Occlusion: Study Protocol for a Non-randomized, 24-Month, Multicenter Study

Background: The management of patients with symptomatic non-acute intracranial artery occlusion (sNA-ICAO), which is a special subset with high morbidity and a high probability of recurrent serious ischemic events despite standard medical therapy (SMT), has been clinically challenging. A number of small-sample clinical studies have also discussed endovascular recanalization (ER) for sNA-ICAO; however, there is currently a lack of evidence from multicenter, prospective, large-sample cohort trials. The purpose of our present study was to evaluate the technical feasibility and safety of ER for sNA-ICAO.Methods: Our group is currently undertaking a multisite, non-randomized cohort, prospective registry study enrolling consecutive patients presenting with sNA-ICAO at 15 centers in China between January 1, 2020 and December 31, 2022. A cohort of patients who received SMT and a cohort of similar patients who received ER plus SMT were constructed and followed up for 2 years. The primary outcome is any stroke from enrollment to 2 years of follow-up. The secondary outcomes are all-cause mortality, mRS score, NIHSS score and cognitive function from enrollment to 30 days, 3 months, 8 months, 12 months, 18 months, and 2 years of follow-up. Descriptive statistics and linear/logistic multiple regression models will be generated. Clinical relevance will be measured as relative risk reduction, absolute risk reduction and the number needed to treat.Discussion: The management of patients with sNA-ICAO has been clinically challenging. The current protocol aims to evaluate the technical feasibility and safety of ER for sNA-ICAO.