Abstract TP10: Clinical and Imaging Outcomes of Patients with Acute Ischemic Stroke and Mild Nihss Treated with Endovascular Therapy

Abstract

Background: The minimal stroke severity justifying endovascular intervention remains elusive; however, a significant proportion of patients presenting with large vessel occlusions and mild symptoms subsequently decline and have poor outcomes. We evaluated clinical outcomes of patients presenting with mild symptoms (NIHSS≤8) undergoing endovascular therapy. Methods: Retrospective analysis of a prospectively collected ET database between September/2010-March/2016. Patients with mild symptoms (baseline NIHSS≤8) were included in the analysis. Primary and secondary efficacy outcomes were defined as the rates of good outcome (90-day mRS 0-2) and successful reperfusion (mTICI 2b-3), respectively. Safety outcome was accessed by rates of any parenchymal hematoma (PH-1 and PH-2) and 90-day mortality. Results: 72 patients with baseline NIHSS≤8 we included in the analysis. Mean age in the overall cohort was 63.3 years (range, 56-69) and 39 patients were men (54%). The mean baseline NIHSS, CTP core volumes, and ASPECTS were 6.3±1.5, 7.5±16.1cc, and 8.5±1.3 respectively. A total of 28 patients (38%) received intravenous tPA. The occlusions were located as follows: proximal MCA-M1 in 29 (40%), MCA-M2 in 20 (27%), ICA terminus in 6 (8%) and vertebrobasilar in 9 patients (12%). Tandem occlusion was documented in 7 patients (9%). Successful reperfusion (TICI 2b-3) was achieved in 67 patients (93%) and 90-day good outcome in 52 (72%). The mean final infarct volume was 32.2±59.9 cc. Any parenchymal hematoma occurred in 4 patients (5%). The 90-day mortality was 9% (n=7). Logistic regression showed that only successful reperfusion (OR 27.7; 95%CI [1.1-655.5]; p=0.04) was an independent predictor of good outcomes. Conclusion: Our findings demonstrate a good safety profile for endovascular therapy in patients presenting with low NIHSS and proximal arterial occlusions. Future prospective controlled studies are warranted.