Purpose: Mechanical thrombectomy has been demonstrated to provide benefits in the treatment of acute ischemic stroke (AIS). But whether to treat AIS patients with a large infarct core remains controversial. Although it is a common practice that patients with large infarct core are not offered endovascular treatment, previous data have consistently shown a proportion of these patients may benefit from IA intervention. The purpose of this study is to identify predictors of good outcomes in an AIS cohort with a large infarct volume previously treated with mechanical thrombectomy.
Hypothesis: We hypothesize that among AIS patients with a large infarct volume, younger patients (≤66 years) who present with lower NIHSS scores will show good functional outcomes (mRS 0-2) at 90 days if treated with mechanical thrombectomy.
Methods: Univariable and multivariable analyses were preformed to identify factors that predict good functional outcomes in AIS patients with ASPECTS 0-5 who were treated with the Penumbra System. Five previous prospective, multicenter trials (PIVOTAL, PICS, RetroSTART, START, SEPARATOR 3D) were included in this study. Patients who presented with symptoms of AIS were analyzed for association between presenting demographics and modified Rankin scale (mRS) score at 90 days in univariate and multivariate analyses.
Results: Data for 614 patients with a median age of 69 years and an NIHSS score of 18 met study criteria. Of these, the 90-day mRS 0-2 rate and mortality were, respectively, 40.23% and 25.41%. Among those with ASPECTS 0-5 (N=93), 17.20% had good functional outcome. An age of ≤66 years was significantly associated with good outcome (p<0.0001) among those with ASPECTS 0-5. Within this age group who had ASPECTS 0-5, a baseline NIHSS score of ≤ 20 (p= 0.0088) with a target vessel location at the MCA (p=0.0210) were also strong predictors of good outcome if treated by mechanical thrombectomy.
Conclusion: These data demonstrate that age ≤66 years, baseline NIHSS score of ≤ 20 with a target vessel location in the MCA are important predictors of good outcomes in an AIS cohort with a large infarct core who are eligible for mechanical thrombectomy.