Results from the ESCAPE-MeVO trial have demonstrated that adding endovascular thrombectomy (EVT) to best medical care provides no additional benefit for patients with acute ischemic stroke due to medium-vessel occlusion (MeVO). The findings, presented at the 2025 International Stroke Conference in Los Angeles and published in the New England Journal of Medicine, challenge current assumptions about stroke intervention strategies.
Trial Design and Patient Characteristics
The parallel, randomized, open-label, blinded study enrolled 530 patients who presented within 12 hours of last seen normal. Participants were randomly assigned to either best medical care (272 patients) or EVT plus best medical care (257 patients). All patients entered the trial with a National Institutes of Health Stroke Scale (NIHSS) score of at least 5, or 3-5 with disabling deficit, and demonstrated high likelihood of salvageable tissue on non-invasive neuroimaging.
Primary Outcomes and Clinical Impact
The study's primary endpoint, achieving a modified Rankin Score (mRS) of 0-1 at 90 days, showed no significant difference between the treatment groups. The risk ratio remained neutral in both unadjusted (RR, 0.97; 95% CI, 0.79-1.18) and adjusted (RR, 0.95; 95% CI, 0.79-1.15) analyses. Secondary endpoints, including mRS scores of 0-2 at 90 days, similarly showed no meaningful differences between the groups.
Safety Concerns and Adverse Events
Dr. Mayank Goyal, clinical professor at the University of Calgary's departments of radiology and clinical neurosciences, presented concerning safety data from the trial. The EVT plus best medical care group demonstrated:
- Higher mortality rate (13.3% vs 8.4%)
- Increased serious adverse events (33.9% vs 25.7%)
- Higher rates of pneumonia (7.0% vs 3.3%)
- More frequent recurrent stroke (5.4% vs 3.7%)
- Greater incidence of stroke progression (5.4% vs 1.8%)
- Higher rates of symptomatic intracerebral hemorrhage (5.4% vs 2.2%)
Functional Outcomes and Quality of Life
The trial revealed better functional outcomes in the best medical care group, with 64.7% of patients achieving a Barthel Index greater than 95 at 90 days, compared to 53.5% in the combination therapy group (adjusted RR, 0.81; 95% CI, 0.71-0.93). Mean stroke volumes were comparable between groups, measuring 4.30 mL in the best medical care group and 4.35 mL in the combination therapy group.
Future Implications and Research Questions
The trial results have sparked important discussions about MeVO treatment approaches. Key questions remain regarding whether MeVOs behave more like end arteries and if earlier intervention might be necessary. The findings also highlight the need to evaluate whether the modified Rankin Score is the most appropriate outcome measure for patients with relatively mild deficits, as typically seen in MeVO cases.
These results suggest a need to carefully reconsider current treatment protocols for medium vessel occlusion strokes, with particular attention to patient selection and risk-benefit assessment when considering endovascular intervention.