Abstract 2850: Natural History of first ever symptomatic Internal Carotid Artery Occlusion (ICAO)

Abstract

INTRODUCTION: Because the natural history of stroke due to ipsilateral ICAO is poorly established, we sought to assess it in a cohort of patients presenting with first ever acute stroke or TIA ipsilateral to an occluded extracranial ICA at a centre where emergent revascularization of ICAO’s (operative or endovascular) is not routinely contemplated. METHODS: Retrospective medical records review of patients admitted to a large academic tertiary care center between January 2006 and April 2011. Inclusion criteria were: 1. First time presentation. 2. Hemispheric ischemic symptoms ipsilateral to an extra-cranial ICAO diagnosed by CT angiography, MR angiography or conventional angiography. 3. Available clinical outcomes 3 months to 1 year. Favorable outcomes were expressed as mRS 0 - 2. All patients were treated with state of the art medical management in compliance with AHA guidelines for treatment of patients with acute ischemic stroke. Delayed revascularization occurred only when partial recanalization on medical therapy was observed. RESULTS: Out of 106 patients identified, 97 had available clinical outcomes. For a detailed description of the cohort see Table-1 . Overall good outcomes were achieved in 26% of patients with an in-hospital mortality of 9.2% and a 3-month to 1-year mortality of 24%. Patients with Tandem Occlusion (TO) had significantly higher NIHSS at presentation and significantly worse outcomes compared to those without TO (mean NIHSS 17 vs. 7, p<0.0001 and mRS<2 in 9% vs. 31%, p=0.042). CONCLUSION: The natural history of first ever stroke due to extracranial ICA occlusion is poor and is comparable to that of stroke due to large vessel intracranial occlusion. Patients with tandem occlusions have significantly worse outcomes than patients with non-tandem occlusions. Our results may provide useful information for planning of future randomized trials comparing revascularization with standard medical therapy in patients with symptomatic ICAO.