Dissection-related tandem occlusion may be different from atherothrombotic tandem occlusion

The optimal endovascular treatment for tandem occlusion in anterior circulation ischaemic stroke remains unknown. The aim of this study was to examine how the aetiology of carotid pathology, dissection versus atherothrombosis, affects clinical outcomes.Data was obtained from prospectively collected registries from two stroke centres between April 2016 and December 2020. Tandem cases with complete cervical internal carotid artery (ICA) occlusion or near-total occlusion (≥90% stenosis) were included. Patients were divided into two groups based on carotid pathology: dissection versus atherothrombosis.A total of 134 patients were included: 36 were dissection and 98 were atherothrombosis. The dissection group had better clinical outcomes compared to the atherothrombosis group, although after adjusting for age and stroke risk factors differences were non-significant. In the non-stented cohort, the dissection patients achieved a better outcome (modified Rankin scale 0-2) than atherothrombotic patients (57% vs. 34%, p=0.04) at 90-days.Dissection-related tandem occlusions appear to have different clinical features from atherothrombotic tandem occlusions which suggests different management strategies are needed.