Abstract T MP56: Challenges in Telethrombolysis: Is Underestimation of Early Ischemic Changes by Stroke Neurologists Associated With Symptomatic Intracranial Hemorrhage?

Background: The Stroke Eastern Saxony Network (SOS-NET) provides telemedical consultations for patients with acute ischemic stroke. Stroke neurologists recommend intravenous (IV) thrombolysis based on cerebral CT scan evaluation with the Alberta Stroke Program Early CT score (ASPECTS). We sought to assess whether: 1) underestimation of early ischemic changes (EIC) was associated with symptomatic intracranial hemorrhage (sICH); 2) whether high ASPECTS predicted favorable outcome after telethrombolysis. Methods: We retrospectively analyzed prospectively collected data of SOS-NET patients who received IV telethrombolysis from 10/08 to 07/12. Two experienced neuroradiologists re-evaluated cerebral CT scans blinded to clinical findings providing reference standard. We defined underestimation of EIC by stroke neurologists as ASPECTS deviations > +1 point and favorable outcome as modified Rankin scale (mRs) scores of 0 to 2 at discharge. We analyzed whether underestimation of EIC was associated with sICH by ECASS-2 criteria and whether ASPECTS dichotomized at 8-10 versus 0-7 was associated with favorable outcome. Results: Of 647 patients who received IV telethrombolysis during the study term, clinical and imaging data were available for 344 patients (median age 76 [IQR 70 - 81] years, NIHSS score 11.5 [IQR 6 - 18], 54.8% female, onset-to-treatment-time 143 minutes [IQR 110 - 190]). At discharge, 91 patients (27.2%) had a favorable outcome. Overall 14 patients (4.2%) suffered thrombolysis-related sICH. Compared to reference, stroke neurologists underestimated EIC extent in 30 patients (9%). ASPECTS deviations were not associated with thrombolysis-related sICH (3.3% vs. 4.3%; p=1.0). Patients with higher ASPECTS (n=299) were more likely to have a favorable outcome than patients with low ASPECTS (n=35) (35.3% vs. 10.3%; p=0.006). Conclusion: Underestimation of EIC by stroke neurologists was rare and not associated with thrombolysis-related sICH in our telestroke network. ASPECTS of 8 - 10 on pretreatment CT is associated with favorable clinical outcome following telethrombolysis.