Indication and outcomes of the reperfusion therapy for acute ischemic stroke patients: comparison between pre- and post-mechanical thrombectomy periods in a single stroke center

Objective: We investigate the options and outcomes of reperfusion therapy for acute ischemic stroke patients by comparing pre- and post-mechanical thrombectomy (MT) periods in a single stroke center. Methods: We defined the 10-month period before approval of mechanical thrombectomy in Japan as the pre-MT period, and the next 19 months after approval as the post-MT period. Between these two periods, we compared the number of acute ischemic stroke patients and the outcomes of these patients based on the reperfusion therapy utilized, which includes intravenous rt-PA (IV-tPA), local intra-arterial fibrinolysis (LIF), MT, and conservative therapy. Results: Of the total patients with cerebral infarction in each period, 44.3% of patients with acute cerebral infarction were admitted to our hospital within 6 hours of onset (pre-MT period) and 52.2% were admitted post-MT. 12.4% (pre-MT) and 25.2% (post-MT) of patients with acute cerebral infarction received IV-tPA therapy. LIF was performed in 5.2% (pre-MT), and MT was performed in 11.6% (post-MT) of acute infarction. Among the patients treated by IV-tPA only, 50.0% achieved a modified Rankin Scale score of ≤2 at 30 days during the pre-MT period, and 48.0% achieved this score in the post-MT period. Among the patients who underwent MT, 37.9% achieved a modified Rankin Scale score of ≤2 at 90 days during the post-MT period. Conclusion: After the approval of MT devices, the percentage of early-admission patients increased during the post-MT period in our hospital. The percentage of patients treated with IV-tPA among patients with acute infarction also increased during the post-MT period. MT was performed for 11.6% of patients, and brought a good outcome of mRS ≤2 at 90 days in 4.4% of the total number of acute ischemic stroke patients.