Abstract TP59: Experience With Endovascular Therapy in Acute Ischemic Stroke Patients Presenting With Low National Institute of Health Stroke Scale Scores

Abstract

Background: Endovascular thrombectomy (ET) is indicated for select patients with anterior circulation large vessel occlusion (ACLVO) with NIHSS > 6. Safety and efficacy of ET in patients with NIHSS <6 and ACLVO is an area of clinical equipoise; we present our experience with this population. Methods: Internal ischemic stroke database was queried for patients with admission NIHSS <6 from 1/2015 to 6/2018. NIHSS on presentation, cortical signs, use of ET (on arrival or after clinical decline) and outcomes were retrospectively collected. Outcomes were compared between patients taken directly for ET and those observed using Mann Whitney U. Results: Of 173 admissions with NIHSS <6 upon arrival, 15 patients had ACLVO. Of those, all had cortical signs; 8 patients were admitted and monitored, 7 patients went directly to ET . Of the 8 monitored patients, 3 (38%) received IVtPA, 6 (75%) underwent rescue ET after clinical decline, all with favorable aspects . Arrival mean NIHSS was 3.3 (4.6), NIHSS at time of ET was 10.6 (7.4). Occlusions were located in the first branch of the middle cerebral artery (M1) in 3 cases, with one case each of M2, internal carotid artery (ICA) and tandem occlusion. A symptomatic intracerebral hemorrhage occurred in a patient with re-occlusion, stent placement and IV antiplatelet use. Five patients (63%) were discharged to an acute rehab facility, the remaining 27% were discharged to home, with NIHSS of 7.7 (7.2) on discharge and mRS of 1.75 (1.5) at 90-day follow-up. Of the 7 patients who proceeded directly to ET, arrival NIHSS was 2.3 (2.2), 43% received IVtPA, occlusions were present in the terminal ICA in all cases, with tandem occlusions additionally present in 3 (43%). One patient clinically worsened and was found to have vasospasm. This same patient was discharged to rehab, the remainder (85.8%) were discharged to home. Discharge stroke scale (mean 1.4, SD 2.2) approached significance (U=11, p=0.052) compared to the observation group, discharge location (chi 3.6, p=0.58) and discharge mRS did not (U=12, p=0.28). Discussion: Despite the low sample size, there was a trend toward significance in discharge NIHSS in favor of patients that were taken directly for ET. Further study regarding management of patients with low NIHSS and LVO is merited.