Abstract WP329: Time Dependent Recanalization and Outcomes in Transferred Stroke Patients With Large Vessel Occlusion (LVO) After IV rt-PA

Background: The time dependent benefit of rt-PA in acute stroke patients is established. However, only limited data exist on LVO outcomes post remote telemedicine administered rt-PA. We report the outcomes of such patients. Methods: A retrospective study of the CPMC stroke database was performed. Primary outcome measures were neurologic outcome at discharge, mortality, and TICI reperfusion scores of mechanical thrombectomy (MT) treated patients. The safety outcome measure was symptomatic hemorrhage rate (SICH; NIHSS > 1 at ≤ 36hr). Results: From 1/2014-2/2018, 233 transferred rt-PA patients were identified. Median age was 73, and median NIHSS 6. Risk factors included hypertension (69%), dyslipidemia (43%), AF (27%), prior stroke/TIA (26%), CAD (26%), DM (24%), smoking (16%), and CHF (13%). The post rt-PA SICH rate was 4% and discharge mRS≤2 rate was 43%. Mortality rate was 11%, 43% required help at discharge, and 40% were discharged home. For the 61 patients who received rt-PA + MT, the SICH rate was 2% and mortality rate 12%. Median discharge NIHSS was 2 and mRS ≤2 rate was 19%. Of the 233 transferred patients, 40 had a pre rt-PA CTA with LVO available for review. For these patients, median time to scan was 76 min. Median time to repeat CTA at CPMC was 180 min. LVO was 80% anterior circulation, clot migration was seen in 5%, and >90% of MT patients had AF. Post rt-PA recanalization rate was 12% (0% posterior circulation). MT after rt-PA was performed in 62% (TICI ≥ 2b 88%). Longer time to treatment trended towards poorer result and longer MT time. Average NIHSS dropped from 12 to 5 and average discharge mRS was 3. Conclusions: These data confirm that remote IV rt-PA followed by MT is safe and effective. Of LVO rt-PA patients 17% experienced full or partial recanalization suggesting repeat imaging is appropriate before initiating MT, possibly with the exception of posterior circulation strokes because of poor response to rt-PA. AF is common and may predict need for MT after rt-PA. A trend was observed towards improved TICI score and shorter recanalization time with a shorter latency between rt-PA and MT. These data support the use of stroke systems of care to ensure rapid triage and treatment of LVO patients.