Mechanical Thrombectomy in Acute Ischemic Stroke: Angiographic Predictors of Outcome

Background: In patients with acute ischemic stroke with large vessel occlusion, various angiographic features are important in patient selection and predicting outcome. Objective: We evaluated angiographic features like collaterals, clot burden score, angiographic recanalization, number of passes, and intracranial atherosclerotic disease (ICAD) with the functional outcome at 90 days. Materials and Methods: This was a retrospective analysis of prospectively collected data of 163 patients with acute ischemic stroke with large vessel occlusion who underwent mechanical thrombectomy within 24 hours of symptom onset. Angiographic data were reviewed blinded to clinical data. The outcome was defined as modified Rankin scale (mRS) at 90 days (good outcome mRS ≤2). Results: The median age of patients was 60 years and 34.4% were females. The median National Institutes of Health Stroke Scale (NIHSS) and Alberta Stroke Programme Early CT Score (ASPECTS) at admission were 17 and 6, respectively. On bivariate analysis, ASPECTS was >6, clot burden score was ≥7, recanalization of TICI was ≥2b, absence of ICAD, showed a positive correlation with the good outcome at 90 days (P-values of 0.003, 0.0001, and 0.03, respectively). Multiple attempts of device passes were associated with poor recanalization (P = 0.001) and it was seen more in ICAD patients. On multivariate analysis, independent predictors of poor outcome were clot burden score <7 (P = 0.043) and TICI score <2b (P = 0.048). Out of 41 patients (26%) with ICAD, 29 had a poor outcome at 90 days. Conclusion: Lower clot burden and less degree of recanalization were associated with poor outcome in acute ischemic stroke due to Large vessel occlusion (LVO). The presence of ICAD also predicted poor outcome.