Introduction: Acute symptomatic occlusion of the internal carotid artery (ICA) is a common pathology in ischemic stroke patients presenting with severe clinical symptomatology. Intravenous thrombolysis (IV-tPA) remains the only approved therapy, despite low re-canalization rates of proximal ICA occlusions. Urgent extra-cranial carotid artery stenting (CAS) is an alternative treatment; we sought to determine its long-term safety and efficacy in acute ischemic stroke.

Methods: Data on patients admitted to our quaternary stroke service with acute ischemic stroke receiving acute stent insertion within 24 hours of stroke onset, between July 2008 and June 2013, was reviewed. Rates of short and long-term in-stent stenosis (>=50%) and its association with poor functional outcome at discharge were studied.

Results: 23 patients had acute ICA occlusions (median NIHSS at presentation=17(IQR=8)). Neurological symptoms were due to hemispheric hypoperfusion in 17.4%(4/23), concurrent intracranial occlusion in 69.6%(16/23), or both in 13.0%(3/23). Stent placement was attempted in all and successful in 91.3%(21/23). Other acute treatments included: IV-tPA(70.8%),IA-tPA/mechanical thrombectomy(25%),anti-platelets(75%) and intra-procedural heparin(75%). A total of 30%(7/23) had poor functional outcome(mRS>3) at discharge(3 symptomatic intracerebral haemorrhages(ICH),4 large strokes).In-hospital death occurred in 17%(4/23: 2 symptomatic ICH, 2 large strokes). Failure to stent resulted in poor functional outcome(mRS> 3) in both cases. Significant in-stent stenosis occurred in 14.3%(3/21) of patients on both short-term(<=7 days) and long-term(>=6 months) follow-up. Multivariable analysis adjusting for age, hypertension, and presenting NIHSS, showed no association of stent stenosis and poor functional outcome at discharge(RR 1.9 CI95 0.1-35, p=0.64).

Conclusions: Acute symptomatic ICA occlusion has high mortality and morbidity. Urgent CAS is a viable option for treating hemispheric hypoperfusion and helping access the concurrent intracranial occlusion. Rate of early in-stent stenosis is high, and significantly higher than the rate reported for elective stenting (6.0% at 2 years), but in-stent stenosis is not a cause of poor neurological outcome at discharge.

Patient Care: This research focuses on a group of high-risk patients in which little evidence analyzing the long-term safety and efficacy of a less well studied treatment is available. Thus, this study helps elucidate the significance of short and long term outcomes encountered by interventionally treated patients presenting with acute symptomatic occlusions of the internal carotid artery (ICA) leading to ischemic stroke. This research opens the door to altering the standard of care offered to this patient population and helps both patients and physicians make a more informed treatment decision.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the causes of neurological symptoms in patients with acute ischemic strokes due to proximal internal carotid artery occlusions 2) Recognize the poor outcomes and lack of accepted therapies in patients with acute ischemic strokes due to proximal internal carotid artery occlusions 3)Identify the difference in rates of stent stenosis between elective and urgent carotid artery stenting procedures

References: 1. Papanagiotou P, Roth C, Walter S, Behnke S, Grunwald IQ, Viera J, Politi M, Korner H, Kostopoulos P, Haass A, Fassbender K, Reith W. Carotid artery stenting in acute stroke. J Am Coll Cardiol. 2012;58:2363-2369 2.Rubiera M, Ribo M, Delgado-Mederos R, Santamarina E, Delgado P, Montaner J, Alvarez-Sabin J, Molina CA. Tandem internal carotid artery/middle cerebral artery occlusion: An independent predictor of poor outcome after systemic thrombolysis. Stroke. 2006;37:2301-2305 3.Restenosis after carotid artery stenting and endarterectomy: a secondary analysis of CREST, a randomised controlled trial. Lancet Neurol 2012; 11: 755–63. (pubmed ID: 22857850)