Acute Management of Medium Vessel Occlusion Stroke: New Evidence and a Path Forward

Acute stroke due to medium vessel occlusion (MeVO) accounts for 25% to 40% of all acute ischemic stroke cases and is associated with substantial morbidity despite current best medical management. This motivated several recently published and ongoing trials that investigate(d) the benefit of endovascular thrombectomy (EVT) for MeVO stroke. Two of these trials have been published, an interim analysis of a third has been presented, and a fourth will be presented soon. The available trial results suggest no difference in outcomes between EVT and best medical management, and a possibility of harm with EVT. Preliminary post hoc analyses have however identified promising patient subgroups that may derive benefit from EVT. Improving EVT tools and techniques, together with adjunctive treatments, may further increase the technical efficacy of MeVO EVT. This review summarizes clinical and imaging features of MeVO stroke, reviews current evidence for medical and endovascular treatment, discusses recent MeVO EVT trial results, and outlines possible pathways forward for future MeVO trials.