Safety Outcomes of Mechanical Thrombectomy Versus Combined Thrombectomy and Intravenous Thrombolysis in Tandem Lesions

ABSTRACT Background and Purpose We aimed to describe the safety and efficacy of mechanical thrombectomy (MT) with or without intravenous thrombolysis (IVT) for patients with tandem lesions (TLs) and whether using intraprocedural antiplatelet therapy (APT) influences MT’s safety with IVT treatment. Methods This is a sub-analysis of a pooled, international multicenter cohort of patients with acute anterior circulation TLs treated with MT. Primary outcomes included symptomatic intracranial hemorrhage (sICH) and parenchymal hematoma type 2 (PH2). Additional outcomes included hemorrhagic transformation (HT), successful reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] 2b-3), complete reperfusion (mTICI 3), favorable functional outcome (90-day modified Rankin score [mRS] 0-2), excellent functional outcome (90-day mRS 0-1), in-hospital mortality, and 90-days mortality. Results Of 691 patients, 599 were included (255 underwent IVT+MT and 344 MT alone). There was no difference in the risk of sICH (aOR=1.43; 95%CI:0.72–2.87; p= 0.308), PH2 (aOR=1.14; 95%CI:0.57– 2.28; p =0.705), and HT (aOR=0.92; 95%CI:0.54–1.57; p =0.751) between the IVT+MT and MT alone groups after adjusting for confounders. There was an IVT-by-intraprocedural APT interaction for sICH ( p interaction =0.031). Administration of IVT was associated with an increased risk of sICH in patients who received IV-APT (aOR=3.58; 95%CI:1.17–10.89; p= 0.025). The IVT+MT group had higher odds of 90-days mRS 0-2 (aOR=1.76; 95%CI:1.05–2.94; p= 0.030). The odds of successful reperfusion, complete reperfusion, 90-days mRS 0-1, in-hospital mortality, or 90-days mortality did not differ between the IVT+MT vs. MT alone groups. Conclusion Our study showed that the combination of IVT with MT for TL did not increase the overall risk of sICH, PH2, or overall HT independently of the cervical revascularization technique used. However, intraprocedural IV-ATP during acute stent implantation might be associated with an increased risk of sICH in patients who received IVT prior to MT. Importantly, IVT+MT treatment was associated with a higher rate of favorable functional outcome at 90 days.