Malignant Brain Edema and Associated Factors in Large Hemispheric Infarction Following Reperfusion Therapy

Objective: This study aimed to explore Malignant Brain Edema (MBE) and associated factors in patients with Large Hemispheric Infarction (LHI) following early reperfusion therapy.

Methods: We consecutively and retrospectively enrolled a cohort of 114 LHI patients who had received early reperfusion therapy, including Intravenous Thrombolysis (IVT) or Endovascular Therapy (EVT) at the hyperacute stage of stroke between January 2009 and December 2018. MBE was defined as a midline shift ≥5 mm, accompanied by signs of herniation. Multivariate logistic analyses were conducted to identify independent factors associated with MBE in LHI patients following early reperfusion therapy.

Results: Among the enrolled patients, 69 (60.53%) were treated with IVT alone and 45 (39.47%) with EVT. Successful recanalization was achieved in 56 (49.12%) patients, while complete recanalization was achieved in 38 (33.33%) patients. After early reperfusion therapy, 50 (43.86%) developed MBE in LHI patients. The MBE group showed higher rates of in-hospital death (54% vs. 4.69%), 3-month mortality (64% vs. 10.94%), and 3-month unfavorable outcomes (90% vs. 64.06%) (all p<0.01). Neither different reperfusion therapy (EVT vs. IVT alone) nor different recanalization status (complete recanalization or not) was independently associated with the development of MBE in LHI patients following reperfusion therapy in multivariate analyses. MBE was independently associated with age [Odds Ratio (OR) 0.953, 95% confidence interval (CI) 0.910-0.999, p =0.044], right hemisphere stroke (OR 4.051, 95% CI 1.035-15.860, p =0.045), previous ischemic stroke or TIA (OR 0.090, 95% CI 0.014-0.571, p =0.011), and hypodensity >1/3 MCA territory (OR 8.071, 95% CI 1.878-34.693, p =0.005). Meanwhile, patients with lower baseline Alberta Stroke Program Early CT Score (ASPECTS) had a trend of higher incidence of MBE following reperfusion therapy (OR 0.710, 95% CI 0.483-1.043, p =0.081).

Conclusion: MBE occurred in nearly one-half of LHI patients following early reperfusion therapy and was related to poor outcomes. An increased risk of MBE was found to be associated with younger age, right hemisphere stroke, absence of a history of ischemic stroke or TIA, and hypodensity >1/3 MCA region on baseline CT images.