Evidence-based optimization of the management of intracranial atherosclerotic disease

Abstract

Dear Editor,The recently published article in Neurological Sciences byMattioni et al. [1] titled ‘Prevalence of intracranial largeartery stenosis and occlusion in patients with acuteischaemic stroke or TIA’ was very interesting. The authorsretrospectively evaluated all consecutive patients whopresented with an ischemic stroke or transient ischemicattack (TIA) and also underwent computed tomographyangiography (CTA) in the emergency room of a singleinstitution in The Netherlands over a 2-year span. Of the220 patients included for analysis, 39 % were found tohave intracranial atherosclerotic disease (ICAD) including35 % with intracranial arterial occlusion, 6 % with steno-sis, and 2 % with both. Multivariate analysis identifiedonly extracranial carotid disease and partial or total anteriorcirculation syndromes as predictors of symptomatic ICAD.Given the contribution of ICAD to ischemic cerebro-vascular disease, optimizing its management has been thesource of significant debate within the neurological andneurointerventional communities for over a decade. In2005, the warfarin–aspirin symptomatic intracranial dis-ease (WASID) trial showed that warfarin and aspirin eachafforded the same protection from recurrent ischemicstroke or TIA, but warfarin was associated with a higherrate of adverse events [2]. For symptomatic patients whofailed medical therapy, endovascular intervention withangioplasty and stenting began to emerge as a potentialtreatment option [3]. In 2005, the United States Food andDrug Administration approved the Wingspan stent (BostonScientific, Natick, MA, USA) under a humanitarian deviceexemption for the treatment of symptomatic ICAD patientswith at least 50 % stenosis of a major intracranial arterywho were refractory to antithrombotic therapy. InitialICAD stenting outcomes with the Wingspan system werepromising, with excellent rates of technical success andacceptably low complication rates [4]. For the time being,it appeared that the neurointerventional community hadprovided an effective solution for symptomatic ICAD.The initial enthusiasm which accompanied the advent ofstenting for ICAD treatment was quelled in 2011 by thesobering results of the stenting and aggressive medicalmanagement for preventing recurrent stroke in intracranialstenosis (SAMMPRIS) trial, which reported higher rates ofcerebral ischemic events in the intervention cohort com-pared to the medical cohort [5]. The medical therapy inSAMMPRIS was composed of dual antiplatelet therapywith aspirin and clopidogrel combined with aggressivemedical treatment of modifiable risk factors such ashypertension and hyperlipidemia. In the modern era ofICAD management, the options for symptomatic patientswho have failed maximal medical management which istypically the same as the therapy utilized in SAMMPRIS, isat best experimental. Although the enthusiasm for ICADtreatment with stenting has waned following SAMMPRIS,neurointerventionalists have continued to offer this thera-peutic option to carefully selected patients. The currentendovascular strategies for symptomatic ICAD are predi-cated on diminishing the incidence of in-stent restenosis(ISR), which has been shown to be relatively high inpatients treated with the Wingspan stent. The use of closedcell, low radial force devices, such as the Enterprise stent(Cordis Corporation, Miami Lakes, FL, USA), balloon-expandable stents, and drug-eluting stents have all beenreported to reduce the rate of ISR in retrospective case