Number of Stent Retriever Passes Associated with Clinical Outcome After Mechanical Thrombectomy in Acute Ischemic Stroke

Objective: To evaluate the association between the number of stent retriever (SR) passes and clinical outcome after mechanical thrombectomy (MT) in patients with acute ischemic stroke(AIS). Methods: We retrospectively analyze data collected from consecutive patients with large vessel occlusion (LVO) in anterior circulation treated with MT. Baseline characteristics, number of SR passes, symptomatic intracranial hemorrhage (sICH), clinical outcome measured by modified Rankin Scale (mRS) at 90 days after MT were collected. Multivariate logistic regression analysis was performed to assess the association between number of SR passes and patients' clinical outcome. Results: 134 patients with LVO achieved successful reperfusion (mTICI 2B/3) were enrolled. Univariate analysis showed that patients with favorable outcomes were less likely to need more than three passes of SR (9.8%vs39.7%, p = 0.001). In a multivariable analysis, baseline NIHSS score (OR 0.922, 95%CI 0.859 similar to 0.990, p = 0.025), more than three passes of SR (OR 0.284, 95%CI0.091 similar to 0.882, p = 0.030) and symptomatic intracranial hemorrhage (OR 0.116,95%CI0.021 similar to 0.650, p = 0.014) each independently predicted poor outcome after MT at 90 days. Conclusion: The need for more than three passes of SR may be used as an independent predictor of poor outcome after MT in patients with acute ischemic stroke at 90 days.