Abstract TP10: Intra-Arterial Thrombolysis After Failed Mechanical Thrombectomy: A STRATIS Registry Subgroup Analysis

Abstract

Background: Limited prospective data exists on the use of intra-arterial (IA) thrombolytics as rescue therapy(RT) after failed mechanical thrombectomy(MT) in acute ischemic stroke(AIS) patients with large vessel occlusions LVO). The aim of this study is to investigate the use of IA recombinant tissue plasminogen activator(IA-rtPA) as RT in the prospective STRATIS Registry. Methods: Data from the STRATIS Registry, a multicenter study of AIS patients treated with the Solitaire stent-retriever as the first choice therapy within 8 hours from symptoms onset, were analyzed. Clinical and angiographic outcomes were compared between patients treated with and without IA-rtPA. Both anterior and posterior circulation occlusions were included in this substudy. Results: Of the 938 STRATIS patients with IA-tPA use reported, 809 and 129 were in the no IA-rtPA(83.2%) and IA-rtPA(13.8%)groups, respectively. No difference was seen in baseline demographics. Site of occlusion was similar between the groups, with the majority occurring in the MCA(72.4% versus 73.6%, p=0.74). IV-rtPA was administered in 63.0% and 70.5% of no IA-rtPA and IA-rtPA patients(p=0.11). Median IA-rtPA dose was 4mg(IQR 2-12). Mean onset to arterial puncture time was shorter in the IA-rtPA group(200.2±104.6 versus 228.2±98.5 minutes, p=0.003); however, mean puncture to procedure end time was longer in the IA-rtPA group(78.7±43.1 versus 63.1±35.9 minutes). Mean number of passes (2.2±1.4 versus 1.8±1.2,p=0.001) and rate of distal embolization(67.8% versus 54.5%, p=0.007) was significantly higher in the IA-rtPA group. Core lab adjudicated substantial reperfusion (mTICI≥2b) was achieved in 88.4% and 84.7% of no IA-rtPA and IA-rtPA patients(p=0.16). No difference was observed in rates of symptomatic intracranial hemorrhage(sICH) (1.4% versus 1.6%,p=0.70), good functional outcome (mRS≥2, 57.3% versus 59.2%, p=0.86), or mortality (15.5% versus 13.3%,p=0.80) at 90-days. Conclusion: Use of IA-rtPA after failed thrombectomy was not associated with an increased risk of sICH or mortality in the STRATIS Registry. These results suggest that IA thrombolysis may be a safe option as rescue therapy in select patients.