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Mechanical thrombectomy in minor stroke due to isolated M2 occlusion: a multicenter retrospective matched analysis
Andrea M Alexandre1, Francesca Colò2, Valerio Brunetti3
1Neuroradiology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.
Background:
The purpose of this study was to evaluate the effectiveness of mechanical thrombectomy (MT) in patients with isolated M2 occlusion and minor symptoms and identify possible baseline predictors of clinical outcome.
Methods:
The databases of 16 high-volume stroke centers were retrospectively screened for consecutive patients with isolated M2 occlusion and a baseline National Institutes of Health Stroke Scale (NIHSS) score ≤5 who received either early MT (eMT) or best medical management (BMM) with the possibility of rescue MT (rMT) on early neurological worsening. Because our patients were not randomized, we used propensity score matching (PSM) to estimate the treatment effect of eMT compared with the BMM/rMT. The primary clinical outcome measure was a 90-day modified Rankin Scale score of 0-1.
Results:
388 patients were initially selected and, after PSM, 100 pairs of patients receiving eMT or BMM/rMT were available for analysis. We found no significant differences in clinical outcome and in safety measures between patients receiving eMT or BMM/rMT. Similar results were also observed after comparison between eMT and rMT. Concerning baseline predicting factors of outcome, the involvement of the M2 inferior branch was associated with a favorable outcome.
Conclusion:
Our multicenter retrospective analysis has shown no benefit of eMT in minor stroke patients with isolated M2 occlusion over a more conservative therapeutic approach. Although our results must be viewed with caution, in these patients it appears reasonable to consider BMM as the first option and rMT in the presence of early neurological deterioration.
Insights
Early mechanical thrombectomy (MT) showed no benefit for minor stroke patients with isolated M2 occlusion compared to best medical management (BMM). Best medical management is recommended as the initial approach for these stroke patients.
Area of Science:
- Neurology
- Interventional Neurology
- Stroke Medicine
Background:
- Mechanical thrombectomy (MT) is a key treatment for acute ischemic stroke.
- Isolated M2 occlusions represent a significant portion of proximal cerebral artery occlusions.
- The optimal treatment strategy for minor strokes due to M2 occlusions remains debated.
Purpose of the Study:
- To evaluate the effectiveness of early mechanical thrombectomy (eMT) versus best medical management (BMM) with rescue MT (rMT) in patients with isolated M2 occlusion and minor stroke symptoms (NIHSS ≤5).
- To identify baseline predictors of clinical outcome in this patient population.
Main Methods:
- A multicenter retrospective analysis of 16 stroke centers.
- Propensity score matching (PSM) was used to compare eMT with BMM/rMT in 100 matched pairs of patients.
- The primary outcome was a 90-day modified Rankin Scale score of 0-1.
Main Results:
- No significant differences in clinical outcomes or safety measures were observed between eMT and BMM/rMT groups.
- Similar outcomes were found when comparing eMT directly with rMT.
- Involvement of the M2 inferior branch was associated with a favorable outcome.
Conclusions:
- Early mechanical thrombectomy (eMT) does not appear to offer a benefit over best medical management (BMM) for patients with minor stroke due to isolated M2 occlusion.
- A conservative approach with BMM as the first option, followed by rescue MT (rMT) if neurological deterioration occurs, may be reasonable.
- Further cautious interpretation is advised due to the retrospective nature of the study.
