Admission Motor Strength Grade Predicts Mortality in Patients with Acute Ischemic Stroke Undergoing Mechanical Thrombectomy

Background: The mortality due to mechanical thrombectomy (MT) in the acute treatment of intracranial arterial occlu- sions can be up to 45%. The SWIFT (Solitaire FR with the Intention for Thrombectomy) and Multi MERCI (mechani- cal embolus removal in cerebral ischemia) trials have evaluated the safety and efficacy of MT. It may be important to determine pre-procedural factors that help predict post-intervention prognosis. We sought to determine if admission medical research council (MRC) motor strength grade along with other factors can be used as predictor of mortality after MT for acute ischemic stroke. Methods: Retrospective analysis of stroke database assessing outcomes in all 62 patients who underwent MT as an intervention for acute ischemic stroke, with or without concurrent intravenous thrombolysis was done. Five baseline variables were included in univariate and multivariate analyses to define the in- dependent predictors of mortality during current hospitalization. The medical research council (MRC) motor grade (0 - 5); modified collateral flow (CS) grading (0 - 3); age; acute and chronic co-morbidities were used as the baseline vari- ables. If motor strength grade were different in upper and lower extremities, then the lower grade was used. Age was analyzed independently as well as dichotomized using 80 as cut-off value. Relevant stroke related acute and chronic co-morbidities were given 1 point each and mean calculated. Results: In the univariate analysis, low (0 - 1) motor strength grade (OR, 0.11; 95% CI, 0.021 - 0.33; p = 0.001) and age (OR, 1.06; 95% CI, 1.02 - 1.12; p = 0.011) was sig- nificantly associated with mortality. The presence of collateral flow, acute and chronic co-morbidities were not signifi- cantly associated with mortality. In the multivariate analysis, motor grade retained its statistical significance for morta- lity (OR, 0.09; 95% CI, 0.01 - 0.32; p = 0.003) along with chronic co-morbidity (OR, 1.52; 95% CI 1.05 - 2.43; p