This study aims to determine the clinical course of acute ischemic stroke due to MeVO with and without intravenous alteplase (IA) treatment. Patients with MeVO from the INTERRSeCT and PRoveIT studies were included. The primary outcome was the Rankin Scale score of 0-1 that described the functional outcomes. Secondary outcomes were the standard odds ratio for a 1-point shift across the modified Rankin Scale and functional independence, defined as a modified Rankin Scale score of 0 to 2.

A total of 72.1% of patients were treated with IA therapy, and 41.8%, recanalization of the occlusion was seen on follow-up CT angiography. 67.4% of patients gained functional independence and excellent functional outcome was achieved by 50.0%, while 8.9% of patients passed away in 3 months. Recanalization was observed in 21.4% of patients who were not treated with alteplase and 47.2% treated with alteplase. Early recanalization was significantly associated with excellent functional outcomes, while intravenous alteplase was not.

Early recanalization was strongly associated with excellent outcomes but occurred in <50% of patients despite intravenous alteplase treatment. The clinical course of acute ischemic stroke due to MeVO with medical management is low: 50% of patients in the study did not achieve excellent outcomes at 90 days with the best medical management, and 33% were not functionally independent. Recanalization on follow-up imaging was strongly associated with favorable outcomes but was only achieved by 47% despite treatment with intravenous alteplase.