Abstract 56: Frequency, Determinants, and Outcomes of Distal Emboli Related to Mechanical Thrombectomy for Acute Ischemic Stroke

Introduction: Clot fragmentation and distal embolization is a feared complication of mechanical thrombectomy treatment for acute ischemic stroke, but the frequency, determinants, and outcomes of distal emboli (DE) with modern endovascular reperfusion techniques is poorly characterized. Gradient refocused echo (GRE) MRI, performed before and after intervention, is a novel technique to directly visualize distal emboli and characterize their causes and consequences. Methods: We analyzed consecutive acute ischemic stroke thrombectomy patients who had MR imaging pre- and post-intervention. Distal emboli were defined as new post-procedure susceptibility vessel signs on GRE, within arteries distal to the target occlusion or within new territories. Results: Among 50 consecutive patients, age was 70.4 (±15.8), 44% were female, and NIHSS was 15 (IQR 8-19). Thrombectomy techniques include retrievers alone in 42%, aspiration alone in 8%, both retriever and aspiration in 50%, and other (e.g. angioplasty, wire macerati...