Reperfusion grade and clinical outcome following medium vessel occlusion thrombectomy in the Endovascular Treatment to Improve Outcomes for Medium Vessel Occlusions (ESCAPE-MeVO) Trial

Background Randomized trials showed that endovascular thrombectomy (EVT) did not improve outcomes in medium vessel occlusion (MeVO) stroke compared with usual care. We investigated whether patients randomized to EVT who achieved near-complete/complete reperfusion had improved clinical outcomes compared with patients randomized to usual care. Methods Post-hoc analysis of ESCAPE-MeVO, which randomized patients with MeVO stroke to undergo EVT in addition to usual care or usual care only. Reperfusion grade in EVT patients was assessed with the MeVO expanded Thrombolysis in Cerebral Infarction (meTICI) score. Regression analyses were used to compare clinical outcomes between EVT patients with near-complete/complete (meTICI 2c-3) reperfusion and usual care patients, and the association between reperfusion grade and clinical outcomes in EVT patients. Results Overall, 253 of 255 (99.2%) patients randomized to EVT had final meTICI scores, of whom 133 (52.2%) achieved meTICI 2c-3 reperfusion. Infarct volumes were lower in EVT meTICI 2c-3 patients than in usual care patients, but there were no significant differences between EVT meTICI 2c-3 and usual care patients for 90-day modified Rankin Scale (mRS) score (adjusted common OR 1.17, 95%CI 0.79 to 1.75). Higher final meTICI scores were associated with improved 90-day mRS and lower infarct volumes in EVT patients. Conclusion Although higher reperfusion grade was associated with smaller infarct volumes, there was no statistically significant difference in 90-day mRS between patients achieving meTICI 2c-3 and those receiving usual care.