Endovascular Therapy Benefit in Distal Vessel Stroke Tied to Severity, Not IVT Status

A secondary analysis of the DISTAL randomized trial found that endovascular therapy's (EVT) effect on 90-day outcomes in medium and distal vessel occlusion (MDVO) stroke did not differ based on whether patients had already received intravenous thrombolysis (IVT), but among IVT-ineligible patients, the benefit depended heavily on stroke severity at admission, emerging most clearly above a baseline National Institutes of Health Stroke Scale (NIHSS) score of 10.

The findings were presented at the World Stroke Congress (WSC 2026), held October 21-23, 2026, in Seoul, Republic of Korea, by lead author Fabiano Cavalcante, of the Netherlands. For context, MDVO refers to occlusion of smaller, more distal cerebral vessels, including the M2 through M4 segments of the middle cerebral artery, the A1 through A3 segments of the anterior cerebral artery, and the P1 through P3 segments of the posterior cerebral artery; unlike large-vessel occlusion stroke, the role of EVT in these occlusions has remained uncertain.^1,2

DISTAL was an international, multicenter, randomized, open-label trial that enrolled 543 patients with isolated MDVO across more than 50 stroke centers in Europe and Israel, randomizing them 1:1 to EVT plus best medical treatment or best medical treatment alone. In the trial's primary results, published in February 2025, the 2 groups did not differ significantly in 90-day disability (common odds ratio for improvement, 0.90; 95% CI, 0.67-1.22; P =.50), and rates of symptomatic intracranial hemorrhage (5.9% with EVT vs 2.6% with medical treatment alone) and death (15.5% vs 14.0%) were not significantly different between groups.²

This secondary analysis restricted the DISTAL population to the 319 patients (59%) who had a baseline NIHSS score greater than 5, denoting non-minor stroke; 216 of these patients (68%) had received IVT before randomization. Overall, there was no significant interaction between treatment assignment and prior IVT use on 90-day modified Rankin Scale (mRS) outcomes (ratio of odds ratios [rOR], 0.56; 95% CI, 0.24-1.32; P for interaction=.18).¹

Among patients who had not received IVT, however, there was a significant interaction between treatment allocation and baseline NIHSS (rOR, 1.49; 95% CI, 1.18-1.90; P for interaction<.001), with EVT associated with increasingly better functional outcomes as stroke severity increased, particularly among patients with an NIHSS score above 10.

The investigators concluded that prior IVT did not significantly modify the functional effect of EVT in non-minor MDVO stroke, but that among IVT-ineligible patients, benefit was highly dependent on baseline severity. They characterized the findings as exploratory and noted that they suggest the threshold for considering endovascular intervention in distal occlusions may be higher than has traditionally been applied to minor-stroke definitions.¹

A second neutral trial in a challenging population

DISTAL was one of 2 major randomized trials evaluating EVT in MDVO stroke to report results in February 2025. The companion ESCAPE-MeVO trial, which enrolled 530 patients with MDVO across multiple countries, similarly found no significant difference between EVT and medical management on its primary outcome; 90-day mRS scores of 0 to 1 were achieved by 41.6% of the EVT group versus 43.1% of the medical-management group, and the EVT group had higher rates of symptomatic intracranial hemorrhage (5.4% vs 2.2%) and 90-day mortality (13.3% vs 8.4%).³

Together, the 2 trials tempered enthusiasm for routinely extending EVT to smaller, more distal occlusions, prompting researchers to look for patient subgroups, such as those with greater baseline severity, in which the procedure's benefit may still outweigh its risk.^1,3

For more coverage of WSC 2026, click here.

REFERENCES
1. Cavalcante F, et al. Endovascular therapy for non-minor MDVO stroke in patients ineligible for intravenous thrombolysis: a secondary analysis of the DISTAL randomized clinical trial. Presented at: World Stroke Congress 2026 (WSC 2026); October 21-23, 2026; Seoul, Republic of Korea.
2. Psychogios M, Brehm A, Ribo M, et al. Endovascular treatment for stroke due to occlusion of medium or distal vessels. N Engl J Med. 2025;392(14):1374-1384. doi:10.1056/NEJMoa2408954
3. Goyal M, Ospel JM, Ganesh A, et al. Endovascular treatment of stroke due to medium-vessel occlusion. N Engl J Med. 2025;392(14):1385-1395. doi:10.1056/NEJMoa2411668