Relationship between hemorrhagic transformation and angiographic early venous filling following mechanical thrombectomy for acute ischemic stroke

Objective To explore the relationship between cerebral hemorrhagic transformation (HT) and angiographic early venous filling (EVF) following mechanical thrombectomy for acute ischemic stroke. Methods A retrospective imaging analysis was performed in the consecutive patients treated from January 2015 to November 2018 for acute anterior circulation large vessel occlusion using mechanical thrombectomy on the Affiliated Hospital of Yangzhou University. The demography, vascular risk factors and other clinical data of the patients were also collected. According to the experimental study of European Cooperative Acute Stroke Study Ⅱ (ECASS Ⅱ), the modified classification of HT after mechanical thrombectomy was divided into HT negative, HT-Ⅰ type and HT-Ⅱ type. The differences in EVF, clinical and demographic characteristics were compared. Multivariate logistic regression analysis was used to identify the independent risk factors for HT and clinical outcome. Diagnostic test characteristics of EVF for HT-Ⅱ type were determined using a receiver operating characteristic curve (ROC) analysis. Results A total of 98 patients with acute ischemic stroke who received mechanical thrombectomy were enrolled, including HT negative in 48 cases (49.0%, 48/98), HT-Ⅰ in 40 cases (40.8%, 40/98) and HT-Ⅱ in 10 cases (10.2%, 10/98). Significant differences were noted in age, and incidence of atrial fibrillation, EVF and poor outcomes among three groups (P<0.05). Multivariate logistic regression analysis showed that EVF [odds ratio (OR) 5.960, 95%CI 1.750-8.960, P=0.001] and atrial fibrillation (OR 3.485, 95%CI 1.962-18.986, P=0.028) were risk factors for the occurrence of HT-Ⅱ after mechanical thrombectomy. No risk factor for HT-Ⅰ was noted. Baseline National Institute of Health Stroke Scale (NIHSS) score (OR 1.162, 95%CI 1.021-1.345, P=0.038), EVF (OR 5.358, 95%CI 1.665-13.653, P=0.006) and HT-Ⅱ (OR 1.326, 95%CI 1.226-2.038, P=0.032) were independent risk factors for poor outcomes. And the sensitivity and specificity of EVF in prediction for HT-Ⅱ were 80.0% and 86.4% respectively, with the area under the ROC curve of 0.832. Conclusion Presence of EVF after mechanical thrombectomy may be the predictor for HT-Ⅱ, which indicates the poor clinical outcomes for acute ischemic stroke patients. Key words: Brain infarction; Radiology, interventional; Postoperative complications; Risk factors; Thrombectomy