8 Intra-arterial thrombolysis as rescue therapy in MCA occlusions: subanalysis from the STRATIS registry

Background and purpose Recent data suggests that intra-arterial (IA) thrombolytics may be a safe rescue therapy (RT) for acute ischemic stroke (AIS) patients after failed mechanical thrombectomy (MT); however, its safety and efficacy in MCA occlusions remains unclear. Here, we investigate the use of IA tissue plasminogen activator (IA-rtPA) as RT in MCA occlusions in the Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke (STRATIS) Registry. Methods The STRATIS Registry was a prospective, multicenter, non-randomized, observational study of AIS LVO patients treated with the Solitaire stent-retriever as the first choice therapy within 8 hours from symptoms onset. Clinical and angiographic outcomes were compared in patients with MCA occlusions treated with and without IA-rtPA. Results A total of 680/938 (72.5%) patients with IA-tPA use harbored MCA occlusions, of which 585 (86.0%) and 95 (14.0%) were in the no IA-rtPA and IA-rtPA groups, respectively. Baseline demographics were well-balanced between the cohorts. The majority of MCA occlusions were located in the M1 segment, with 76.1% in the no IA-rtPA group and 74.7% in the IA-rtPA group (p=0.80). IV-rtPA was administered in 64.4% and 71.6% of the no IA-rtPA and IA-rtPA patients (p=0.20). Median IA-rtPA dose was 4mg (IQR 2–10) in the IA-rtPA cohort. Onset to puncture time was less than 6 hours in 88.6% (597/674) of patients. Mean onset to arterial puncture time was shorter in the IA-rtPA group (196.7±109.9 versus 228.2±97.9 minutes, p=0.004); however, mean puncture to procedure end time was longer in the IA-rtPA group than the no IA-rtPA group (74.5±41.5 versus 59.5±33.6 minutes). Mean number of passes (2.0±1.2 versus 1.6±1.0, p=0.005) and rate of distal embolization (53.4% versus 72.1%, p=0.001) were significantly higher in the IA-rtPA group. The rate of substantial reperfusion (mTICI≥2b) was similar in the cohorts (89.9% versus 86.0%, p=0.28). Rates of symptomatic intracranial hemorrhage (sICH) (1.7% versus 2.2%, p=0.68), good functional outcome (mRS≥2, 60.5% versus 58.0%, p=0.85), and mortality (13.9% versus 13.6%, p=0.96) at 90days did not differ between the two groups. Conclusion Use of IA-rtPA as rescue therapy after failed mechanical thrombectomy in MCA occlusions was not associated with an increased risk of sICH or mortality in the STRATIS Registry. More studies are needed to understand the safety and efficacy of IA thrombolysis as rescue therapy in this patient population. Disclosures A. Castonguay: None. S. Zaidi: None. M. Jumaa: None. O. Zaidat: None. D. Liebeskind: None. H. Salahuddin: None. N. Mueller-Kronast: None.