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Optimized Management of Endovascular Treatment for Acute Ischemic Stroke
Published on: January 18, 2018
Mechanical Thrombectomy for M2 Segment Occlusion in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis
Yuxuan Xing1, Xin Jiang2, Kangtai Su1
1The First Clinical Medical School, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi, China.
Background:
The safety and benefit of mechanical thrombectomy (MT) in the treatment of acute ischemic stroke (AIS) patients with M2 segment middle cerebral artery occlusions remain uncertain.
Objective:
To investigate the benefit of mechanical thrombectomy for M2 occlusion compared with M1 occlusion in patients with AIS.
Methods:
The PubMed, Embase, and Cochrane Library databases were searched from inception to April 2021 to identify relevant articles. The main results comprised 90-day functional independence (modified Rankin Score from 0-2), successful recanalization (thrombectomy in cerebral infarction [TICI] 2b/3), mortality, and rates of symptomatic intracerebral hemorrhage after using modern thrombectomy devices. Odds ratios (ORs) were generated for binary variants. ReviewManager 5.3 software was used.
Results:
Ultimately, a total of 14 trials were included, with 3454 participants enrolled. MT for M2 occlusion had a higher rate of 3-month functional independence than M1 occlusion, but the difference was nonsignificant (OR: 1.19, 95% confidence interval [CI]: 0.98 to 1.46). The TICI2b/3 scores (OR: 0.71, 95% CI: 0.58-0.88) in M2 occlusion were remarkably lower than those in M1. The mortality and symptomatic intracerebral hemorrhage rates were comparable between the 2 groups. When comparing M2 and M1 occlusions, we found that there was no significant difference between stent retriever and aspiration in the modified Rankin Score (0-2) after AIS, but aspiration exerted an eminently higher recanalization rate with regard to TICI2b/3 (OR: 0.77, 95% CI: 0.61-0.96).
Conclusions:
Compared with M1 occlusion, patients with M2 occlusion treated by MT demonstrated similar clinical outcomes in this study. Moreover, there was no difference between stent retriever and aspiration in treating M2 occlusion in terms of functional independence at 90 days. However, aspiration exerted a conspicuously higher recanalization rate in M2 occlusion than in M1 occlusion.
Insights
Mechanical thrombectomy for M2 occlusions in acute ischemic stroke shows similar functional outcomes to M1 occlusions. Aspiration devices offer higher recanalization rates for M2 occlusions compared to M1.
Area of Science:
- Neurology
- Interventional Neuroradiology
- Stroke Medicine
Background:
- The efficacy of mechanical thrombectomy (MT) for acute ischemic stroke (AIS) involving M2 segment middle cerebral artery occlusions requires further investigation.
- Uncertainty exists regarding the safety and benefits of MT in this specific patient subgroup.
Purpose of the Study:
- To compare the effectiveness of MT in patients with M2 occlusions versus M1 occlusions in AIS.
- To evaluate functional independence, recanalization rates, mortality, and symptomatic intracerebral hemorrhage.
Main Methods:
- A systematic review and meta-analysis of 14 trials (3454 participants) from PubMed, Embase, and Cochrane Library (up to April 2021).
- Analysis focused on 90-day functional independence (modified Rankin Score 0-2), successful recanalization (TICI 2b/3), mortality, and symptomatic intracerebral hemorrhage.
- Odds ratios were calculated using ReviewManager 5.3 software.
Main Results:
- MT for M2 occlusions showed a nonsignificant trend towards higher 90-day functional independence compared to M1 occlusions (OR: 1.19).
- Recanalization rates (TICI 2b/3) were significantly lower for M2 occlusions than M1 occlusions (OR: 0.71).
- Mortality and symptomatic intracerebral hemorrhage rates were comparable between M1 and M2 occlusion groups. Aspiration devices demonstrated higher recanalization rates (TICI 2b/3) than stent retrievers in M2 occlusions (OR: 0.77).
Conclusions:
- MT for M2 occlusions yields similar clinical outcomes to M1 occlusions in AIS patients.
- Functional independence at 90 days did not differ significantly between stent retriever and aspiration devices for M2 occlusions.
- Aspiration devices achieved a significantly higher recanalization rate in M2 occlusions compared to M1 occlusions.
