Abstract 83: Successful Recanalization With Intravenous Thrombolysis Preceding Mechanical Thrombectomy in Large Vessel Occlusions: A Systematic Review and Meta-Analysis

Abstract

Introduction: Although current guidelines advocate pretreatment with intravenous thrombolysis (IVT) in all eligible patients with emergent large vessel occlusion (ELVO) prior to mechanical thrombectomy (MT), there are observational data questioning the efficacy of IVT pretreatment in patients with ELVO. One of the main arguments in favour of IVT pretreatment is the potential for tPA-induced successful recanalization (SR) before the onset of endovascular procedure averting the need for MT. Methods: We performed a systematic review in MEDLINE and SCOPUS databases for randomized clinical trials (RCTs) and observational cohorts providing rates of SR with IVT in patients with ELVO before the initiation of MT. We also performed subgroup analyses according to study type (RCTs or observational) and according to the inclusion per-protocol of patients with tandem (intracranial/extracranial) occlusions. Results: We identified 10 eligible studies (7 RCTs & 3 observational cohorts), including 1227 ELVO patients (median NIHSS score: 17). SR following IVT and before MT was documented in 9% (95%CI: 5%-14%; I 2 =85.4%) of ELVO patients, with no significant (p=0.263) differences among RCTs and observational cohorts (Figure). Higher tPA-induced SR rates were identified in studies reporting exclusion of patients with tandem occlusions compared to the rest (15%, 95%CI: 6%-26% vs 5%, 95%CI: 2%-9%; p for subgroup difference=0.052). Conclusions: Pretreatment with IVT in ELVO patients eligible for MT results in SR in almost one out of ten cases, negating the need for additional endovascular reperfusion. Tandem occlusions appear to be the least responsive to IVT pretreatment.