BackgroundIntravenous alteplase is currently the only evidence-based treatment for medium-vessel occlusion stroke (MeVO; M2/3, A2/3, and P2/3 vessel segment occlusions), but due to its limited efficacy, endovascular treatment (EVT) is increasingly performed in these patients. In this case-based survey study, we examined the influence of intravenous alteplase treatment on physicians’ decision-making for EVT in primary MeVO stroke.MethodsIn an international web-based survey among physicians involved in acute stroke care, participants provided their EVT decision for six quasi-identical fictional MeVO case scenarios (three with and without intravenous alteplase administered). Each scenario showed radiological images and clinical information in the form of a short case vignette. We compared EVT decisions (“immediate EVT”, “no EVT”, or “wait for alteplase effect” [in case scenarios with alteplase treatment only]) for case scenarios with and without alteplase treatment. Clustered multivariable logistic regression was performed to assess the effect of alteplase on treatment decision.ResultsThe survey was completed by 366 physicians from 44 countries, resulting in 2196 responses included in this study. In alteplase-treated cases, 641/1098 (58.4%) responses favored immediate EVT, (279/1098 [25.4%]) favored no EVT and 178/1098 (16.2%) opted to wait for alteplase effect. In non-alteplase-treated case scenarios, 846/1098 (78.7%) were in favor of and 252/1098 (21.3%) against EVT. Intravenous alteplase was associated with a lower chance of a decision in favor of immediate EVT (adjusted OR 0.38 [95%CI 0.31 to 0.46]).ConclusionsIntravenous alteplase is an important factor in EVT decision-making for MeVO stroke. However, even in alteplase-treated patients, more than half of the physicians decided to proceed with EVT without waiting for alteplase effect.