E-108\u2005Incidence of in-situ thrombosis in acute large vessel occlusion: review of 168 thrombectomy patients

Abstract

Introduction Acute large vessel occlusion (LVO) presenting with stroke symptoms may occur as a result of embolic occlusion, in-situ thrombosis of intracranial atherosclerotic stenosis or intracranial arterial dissection, vasculopathy, or other etiologies. The literature reflects variation in the incidence of these pathologies depending on geography, heredity, smoking history, as well as others factors. Methods We retrospectively analyzed a consecutive series of 168 patients who presented with acute stroke symptoms and imaging revealing intracranial large vessel occlusion, who underwent cerebral angiography and attempted endovascular thrombectomy. Patients who underwent successful thrombectomy with no evidence of post-thrombectomy underlying ICAD lesion, dissection, or other vascular abnormality were presumed to have an embolic cause of their LVO. Patients who had an underlying vessel abnormality post-thrombectomy (exclusive of mechanical vasospasm) and no history of atrial fibrillation or other embolic risk factor were categorized as in-situthrombosis. Results Of the 168 patients, 151 arteries were revascularized with no post-thrombectomy vessel abnormality, indicating potential embolic cause. The remaining 17 patients had an underlying abnormality of which 15 appeared to be atherosclerotic in nature and 2 with underlying arterial dissection. These patients were initially indentified by the inability to pass the occlusive lesion with a J shape microwire. All 17 patients underwent angioplasty of their stenotic lesion at the time of thrombectomy. In addition, 13 patients underwent intracranial stenting. This included 8 patients stented acutely and 5 patients stented in a delayed fashion. Stenting was typically performed acutely if there was significant arterial recoil or lack of sufficient flow following angioplasty alone. One patient appeared to have an acute stent thrombosis within 12 hours of stenting.Abstract E-108 Figure 1 Conclusions Although the majority of acute LVO stroke was embolic in this series, 10.1% of patients appeared to have a clinical picture more consistent with in-situthrombosis and 8.9% of the total patient cohort appeared to have an underlying ICAD lesion. Within this regional series, in-situ occlusion is a less common, but significant pathology, that may require different treatment strategies that conventional thrombectomy for LVO. Disclosures M. Alexander: 2; C; Stryker Neurovascular, Medtronic, Penumbra, Inc. Z. Barnard: None.