Abstract WP24: Angiographic Blush After Mechanical Thrombectomy is Associated With Hemorrhagic Conversion of Ischemic Stroke

Abstract

Introduction: Risk factors for hemorrhagic transformation of ischemic stroke after mechanical thrombectomy are not well established. Hypothesis: Prominent cerebral tissue vascularity on angiography after recanalization with thrombectomy (angiographic blush) is associated with hemorrhagic transformation. Methods: Among patients in the Cornell AcutE Stroke Academic Registry (CAESAR), we identified those who underwent stent-retriever-based thrombectomy for anterior circulation occlusion between 2012 and 2015. The presence of hemorrhagic transformation and angiographic blush were determined by neuroradiologists and neurointerventionalists. We identified angiographic blush as hypervascularity with or without early venous drainage. Hemorrhagic transformation was defined using CT or MRI studies performed within 7 days of thrombectomy. Our primary outcome was the volume of hemorrhagic transformation, determined using 3D-Slicer software. Our secondary outcome was the presence of any hemorrhagic transformation. Using a doubly robust estimator, we analyzed whether the presence of angiographic blush after recanalization was associated with an increased volume of hemorrhagic transformation after adjustment for demographics and previously published risk factors for hemorrhagic transformation. Results: Among 48 eligible patients (median age, 68 years; median NIHSS score, 18), 31 (64.6%) had angiographic blush and 26 (54.2%) had hemorrhagic transformation (mean volume, 7.6 cc). Patients with angiographic blush had lower TICI scores and had more often received alteplase. After adjustment for demographics and risk factors for hemorrhagic transformation, the presence of angiographic blush was significantly associated with an increased volume of hemorrhagic transformation: mean volume, 10.3 (95% CI, 3.7-16.9) cc with any blush versus 1.8 (95% CI, 0.1-3.4) cc without any blush (p=0.01). Angiographic blush was nonsignificantly associated with the presence of any hemorrhagic transformation (odds ratio, 1.5; 95% CI, 0.9-2.5). Conclusions: In a single-center study, we found that the presence of angiographic blush after mechanical thrombectomy was independently associated with an increased volume of hemorrhagic transformation.