Abstract TP22: Outcomes After Endovascular Therapy in a Population With Mild Acute Ischemic Stroke: A 6.5 Year Observational Cohort Study at a High Volume Comprehensive Stroke Center

Abstract

Introduction: Despite suffering mild acute ischemic strokes (AIS, NIHSS≤7), patients have a non-zero risk of significant morbidity and mortality. Intra-arterial therapy (IAT) is clearly effective in non-mild AIS, but mild AISs have been excluded from IAT trials, limiting our understanding of their outcomes after IAT. The objective of this study was to report on patient outcomes in a mild AIS population who received IAT. Methods: We included all adults (≥18) with a mild AIS admitted over 6.5 years to a high-volume comprehensive stroke center and who received IAT. Patients were excluded for any contraindication to IAT (n=240). Outcomes were symptomatic ICH (sICH), in-hospital mortality, discharge mRS ≤2, and an improvement in NIHSS at discharge (>2 vs ≤2). Results: There were 55 patients included in the study (Table 1). Overall, patients were predominately aged 55-79 years, admitted with an NIHSS 4-7, or had hypertension. 72% of patients either had a cardioembolic or large vessel occlusion (LVO), and 73% arrived either 0h to 4.5h, or >6h to <12h from symptom onset. 15 patients also received IV-tPA. There were no sICHs. Mortality was 9%; a majority of deaths were in males, patients with ages 55-79, LVOs, or an early symptom to arrival time. 42% of patients showed a 3-point improvement in NIHSS at discharge; a majority of these patients were white, aged 55-79, or had hyperlipidemia. Ultimately, 45% were discharged with an mRS ≥2. There were no cerebral artery perforations or groin complications. Conclusions: These data highlight the safety of IAT in patients with mild AIS, mirroring the results seen in recent large randomized clinical trials showing efficacy of IAT in the non-mild AIS population. Patients in our study had a non-existent risk of sICH, and a mortality rate similar to literature examining IV-tPA administration in patients with mild AIS. Furthermore, a large proportion of patients showed a clinically meaningful improvement in NIHSS, or were discharged with a favorable mRS.