Abstract
AIMS: Although intravenous thrombolysis (IVT) has not shown confirmative effects on the outcomes of patients receiving successful thrombectomy, it might influence the outcomes of a subset of these patients. This study aims to evaluate whether the effects of IVT depend on final reperfusion grade in patients with successful thrombectomy. METHODS: This is a single-center, retrospective analysis of patients with an acute anterior circulation large-vessel occlusion and a successful thrombectomy between January 2020 and June 2022. Final reperfusion grade was evaluated by the modified Thrombolysis in Cerebral Infarction (mTICI) score, which was dichotomized into incomplete (mTICI 2b) and complete (mTICI 3) reperfusion. The primary outcome was functional independence (90-day modified Rankin Scale score 0-2). Safety outcomes were 24-h symptomatic intracranial hemorrhage and 90-day all-cause mortality. Multivariable logistic regression analyses were used to assess the interactions between IVT treatment and final reperfusion grade on outcomes. RESULTS: When comparing all 167 patients enrolled in the study, IVT did not influence the extent of functional independence (adjusted OR: 1.38; 95% CI: 0.65-2.95; p = 0.397). The effect of IVT on functional independence depended on final reperfusion grade (p = 0.016). IVT benefited patients with incomplete reperfusion (adjusted OR: 3.70; 95% CI 1.21-11.30; p = 0.022), but not those with complete reperfusion (adjusted OR: 0.48, 95% CI: 0.14-1.59; p = 0.229). IVT was not associated with 24-h symptomatic intracerebral hemorrhage (p = 0.190) or 90-day all-cause mortality (p = 0.545). CONCLUSIONS: The effect of IVT on functional independence depended on final reperfusion grade in patients with successful thrombectomy. IVT appeared to benefit patients with incomplete reperfusion, but not those with complete reperfusion. Because reperfusion grade cannot be determined prior to endovascular treatment, this study argues against withholding IVT in IVT-eligible patients.