Impact of Acute Interventions for Ischemic Strokes on Infarcted Tissue Volume: Comparison of MRI Profiles (P3.203)

Objective: To determine whether mechanical thrombectomy (MTB) alone or MTB with rTPA (combined therapy) for anterior circulation LVO stroke has significant impact in minimizing progression of infarct volume. Background: MTB has been recently proven an effective rescue therapy for anterior circulation LVO stroke. However, much uncertainty exists regarding the efficacy of MTB alone vs. combined therapy. Design/Methods: A retrospective chart review was performed of patients with anterior circulation LVO stroke treated with MTB alone or combined therapy from 05/2011 to 06/2017. Infarcted volumes of pre and post therapy (within 5 days) on MRI were calculated using ABC/2. Patient characteristics (i.e. stroke risk factors and NIHSS) were also obtained. The relationship between infarcted volumes, both acute intervention modalities, and patient characteristics were analyzed using a 1- within factor and 1-between factor analysis of variance and linear regression respectively. Results: Of 158 patients reviewed, 29 were included; 16 in MTB alone and 13 in combined therapy. Pre-intervention mean infarct volumes for MTB alone and combined therapy were 19.56cc+20.41SD (or 95% CI=8.69, 30.44) and 16.62cc+20.43SD (95% CI=4.27, 28.96) respectively (p=0.3111) and post-intervention were 101.1+94.64SD (95% CI=50.63, 151.50) and 61.69+58.01SD (95% CI=26.64, 96.75) respectively (p=0.1330). Mean differences of infarct volumes pre & post intervention for each modality are 81.5+94.81SD (p=0.0008) and 45.08+48.48SD (p=0.0091), respectively. Although comparison of mean differences in infarct volumes pre and post-intervention between modalities was not significant (p=0.7385), individuals with MTB alone appeared to have twice increase in infarct volume compared to combined therapy. Effects of patient characteristics on infarct volume were not significant. Conclusions: In our study, although we did not find significant difference in mean infarct volume post intervention between MTB and combined therapy, we did observe a trend of increase in infarct volume in patients treated with MTB alone. This result should be further evaluated in larger, prospective studies.