Safety and efficacy of mechanical thrombectomy for acute ischemic stroke with volume over 50 mL and significant perfusion mismatch.

Background: This study aims to address the safety and efficacy of mechanical thrombectomy (MT) in acute ischemic stroke with an established infarction equal to or >50 mL with a significant difference between penumbra and established infarction detected by perfusion cerebral computed tomography (CT) with the Rapid^® system.

Methods: This was a retrospective case-control study. Patients diagnosed with established and extensive ischemic stroke, defined by an ischemic volume equal to or >50 mL on CT or magnetic resonance imaging perfusion using the RAPID^® system, were examined. The intervention group received endovascular interventional treatment with or without recombinant tissue plasminogen activator (rt-PA) in addition to standard therapy, and the control group received conservative treatment with or without rt-PA plus standard therapy.

Results: A total of 59 patients were enrolled, including 38 in the intervention group and 21 in the control group. Baseline characteristics were similar between groups. Patient National Institutes of Health Stroke Scale at discharge was significantly different between the control (median 30, interquartile range [IQR] 13) and intervention group (median 8, IQR 14) (P < 0.001). Modified Rankin scale (mRS) scores were significantly different at discharge between intervention (median mRS 2, IQR 3) and controls (median mRS 5, IQR 1) (P = 0.002). These mRS differences remained significant at 90 days, with median (IQR) values of 2 (2.75) and 5 (1), respectively (P < 0.001).

Conclusion: MT is safe and effective for large-core ischemic strokes with significant perfusion mismatch, leading to better functional outcomes without significant complications compared to the best medical treatment.