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Endovascular Therapy for Late-Window M2-Segment Middle Cerebral Artery Occlusion: Analysis of the CLEAR Study
Simon Winzer1,2, Daniel P O Kaiser3,2, Muhammad M Qureshi4,5
1Neurology (S.W., V.P.), Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany.
Background:
There is uncertainty about whether patients with M2 occlusion benefit from endovascular therapy (EVT) in the late (6-24-hour) time window. We evaluated the clinical outcomes of patients with M2 occlusion selected for EVT compared with those who received medical management (MM) in the late window.
Methods:
This multinational cohort study was conducted at 66 sites across 10 countries (January 2014 to May 2022). We included consecutive patients with late-window stroke due to M2 occlusion, baseline National Institutes of Health Stroke Scale score of ≥5, and premorbid modified Rankin Scale score of ≤2 who received EVT or MM alone. The primary end point was 90-day ordinal shift in the modified Rankin Scale score. Safety end points were symptomatic intracranial hemorrhage and 90-day mortality. Differences in outcomes were determined using inverse probability of treatment weighting-adjusted logistic regression models.
Results:
Among 5098 patients, 496 met inclusion criteria (median [interquartile range] age, 74 years [62-81 years]; baseline National Institutes of Health Stroke Scale score, 12 [8-17]), of whom 394 (79.4%) received EVT and 102 (20.6%) MM. In inverse probability of treatment weighting adjusted analyses, there was no favorable 90-day ordinal modified Rankin Scale shift (odds ratio, 1.39 [95% CI, 0.92-2.12]) and no difference of functional independence rates (modified Rankin Scale score of 0-2; odds ratio, 1.72 [95% CI, 0.93-3.15]) with EVT compared with MM. Moreover, symptomatic intracranial hemorrhage risk (odds ratio, 3.46 [95% CI, 0.50-23.92]) and 90-day mortality (odds ratio, 1.11 [95% CI, 0.66-1.87]) were not statistically different between treatment groups.
Conclusions:
In patients with M2 occlusion in the 6- to 24-hour time window, there was no difference in disability outcomes or symptomatic intracranial hemorrhage risk between patients treated with EVT compared with MM. Results of ongoing randomized trials will provide further insight.
Registration:
URL: https://www.clinicaltrials.gov; Unique identifier: NCT04096248.
Insights
Endovascular therapy (EVT) did not show improved outcomes for stroke patients with M2 occlusion in the 6-24 hour window compared to medical management (MM). This study found no significant difference in disability or safety between EVT and MM for these patients.
Area of Science:
- Neurology
- Interventional Neurology
- Stroke Medicine
Background:
- Uncertainty exists regarding the efficacy of endovascular therapy (EVT) for M2 occlusion strokes within the 6-24 hour window.
- Evaluating clinical outcomes of EVT versus medical management (MM) in this late time window is crucial for treatment guidelines.
Purpose of the Study:
- To compare the clinical outcomes of patients with M2 occlusion receiving EVT versus MM in the late (6-24 hour) time window.
- To assess the impact of EVT on functional independence and safety endpoints in this patient population.
Main Methods:
- A multinational cohort study involving 66 sites across 10 countries.
- Inclusion criteria: M2 occlusion stroke, NIHSS ≥5, mRS ≤2, treated with EVT or MM alone in the 6-24 hour window.
- Primary endpoint: 90-day ordinal shift in modified Rankin Scale (mRS). Safety endpoints: symptomatic intracranial hemorrhage and 90-day mortality. Analysis used inverse probability of treatment weighting (IPTW).
Main Results:
- Of 496 patients, 394 (79.4%) received EVT and 102 (20.6%) received MM.
- IPTW-adjusted analyses showed no significant difference in 90-day ordinal mRS shift (OR, 1.39; 95% CI, 0.92-2.12) or functional independence (mRS 0-2) (OR, 1.72; 95% CI, 0.93-3.15) between EVT and MM.
- No statistically significant differences were observed in symptomatic intracranial hemorrhage (OR, 3.46; 95% CI, 0.50-23.92) or 90-day mortality (OR, 1.11; 95% CI, 0.66-1.87).
Conclusions:
- Endovascular therapy (EVT) does not appear to offer significant benefits over medical management (MM) for M2 occlusion strokes in the 6-24 hour window regarding functional outcomes or safety.
- Further insights are expected from ongoing randomized clinical trials to clarify the role of EVT in this specific stroke scenario.
