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Author Spotlight: Assessing Ischemic Stroke Damage Through Middle Cerebral Artery Occlusion Model
Published on: August 11, 2023
Occlusion Location of Middle Cerebral Artery Stroke and Outcome after Endovascular Treatment
Marcel Arnold1, Agnieszka Slezak, Marwan El-Koussy
1Department of Neurology, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland.
Background:
The aim of this study was to analyze the influence of the location of middle cerebral artery (MCA) occlusion on recanalization, complications and outcome after endovascular therapy.
Methods:
Four-hundred sixty-four patients with acute MCA occlusions were treated with endovascular therapy.
Results:
Two-hundred ninety-three patients had M1 occlusions, 116 had M2, and 55 had M3/4 occlusions. Partial or complete recanalization was more frequently achieved in M1 (76.8%) than in M2 (59.1%) or M3/4 (47.3%, p < 0.001) occlusions, but favorable outcome (modified Rankin Scale 0-2) was less frequent in M1 (50.9%) than M2 (63.7%) or M3/4 (72.7%, p = 0.018) occlusions. Symptomatic intracerebral hemorrhage (ICH) did not differ between occlusion sites, but asymptomatic ICH was more common in M1 (22.6%) than in M2 occlusions (8.6%, p = 0.003). Recanalization was associated with favorable outcome in M1 (p < 0.001) and proximal M2 (p = 0.003) but not in distal M2 or M3/4 occlusions.
Conclusions:
Recanalization with endovascular therapy was more frequently achieved in patients with proximal than distal MCA occlusions, but recanalization was associated with favorable outcome only in M1 and proximal M2 occlusions. Outcome was better with distal than proximal occlusions. This study shows that recanalization can be used as a surrogate marker for clinical outcome only in patients with proximal occlusions.
Insights
Endovascular therapy for middle cerebral artery (MCA) occlusions achieved recanalization more often in proximal sites. However, favorable outcomes were linked to recanalization only in proximal occlusions, with better results overall for distal occlusions.
Area of Science:
- Neurology
- Interventional Radiology
- Vascular Surgery
Background:
- Endovascular therapy is a key treatment for acute ischemic stroke caused by middle cerebral artery (MCA) occlusions.
- The location of the MCA occlusion may influence treatment success and patient outcomes.
Purpose of the Study:
- To investigate how the specific location of MCA occlusion affects recanalization rates, complications, and clinical outcomes following endovascular therapy.
Main Methods:
- Analysis of 464 patients with acute MCA occlusions treated with endovascular therapy.
- Categorization of occlusions into M1, M2, and M3/4 segments.
- Assessment of recanalization, symptomatic and asymptomatic intracranial hemorrhage (ICH), and functional outcomes (modified Rankin Scale).
Main Results:
- Recanalization was more frequent in M1 (76.8%) than M2 (59.1%) or M3/4 (47.3%) occlusions.
- Favorable outcomes (mRS 0-2) were less frequent in M1 (50.9%) compared to M2 (63.7%) or M3/4 (72.7%) occlusions.
- Recanalization correlated with favorable outcomes in M1 and proximal M2 occlusions, but not distal M2 or M3/4 occlusions. Asymptomatic ICH was more common in M1 occlusions.
Conclusions:
- While endovascular therapy achieves higher recanalization rates in proximal MCA occlusions (M1, proximal M2), it only predicts favorable outcomes in these segments.
- Distal MCA occlusions (M2, M3/4) were associated with better clinical outcomes despite lower recanalization rates.
- Recanalization serves as a reliable surrogate marker for clinical outcome solely in proximal MCA occlusions.
