Outcomes after Endovascular Therapy in A Population with Mild Acute Ischemic Stroke and Large Vessel Occlusion: Does Treatment Help?

Introduction: Patients with mild acute ischemic strokes (NIHSS ≤7, AISs) have been excluded from intra-arterial therapy (IAT) trials, limiting our understanding of their outcomes after IAT. Mild AIS with large vessel occlusions (LVOs) represent a fragile subset of mild AISs. Despite a low NIHSS, these patients can have a sudden failure of collateral circulation and deteriorate rapidly, resulting in significant disability. The objective of this study was to compare patient outcomes between those with mild AIS and LVO who did and did not received IAT. Methods: We included all adults (≥18) with a mild AIS due to an LVO admitted over 6.5 years to a high-volume comprehensive stroke center. Patients were excluded for any contraindication to IAT (n=240). Comparison groups were IAT vs. no therapy. Outcomes were sICH, in-hospital mortality, discharge mRS ≤2, and an improvement in NIHSS at discharge (>2 vs ≤2). Fisher’s, chi-squared, and logistic regression compared outcomes between groups. Results: There were 75 patients included in the study (Table 1). Overall 21% received treatment, and a majority of patients were 55-79 years, presented with hypertension and hyperlipidemia, and arrived within 4.5h from symptom onset. 7 patients also received IV-tPA. The IAT group had a significantly larger proportion of males, and hypo-mild strokes (NIHSS 4-7). There was one sICH in the no therapy group, and overall few deaths (Table 1). There was no significant difference between groups in improvement in NIHSS, and after adjusting for admission NIHSS, there was no significant difference in favorable discharge mRS. There were no IAT procedure complications. Conclusions: It remains to be seen whether IAT is beneficial in patients with mild AIS and LVO. Future, interventional, multi-center studies are needed to definitively determine the efficacy of IAT. Though these data come from a small patient population, they offer an insight into the potential safety of IAT in a fragile stroke population.