title: Choices of Stent and Cerebral Protection in the Ongoing ACST-2 Trial: A Descriptive Study.
abstract: OBJECTIVE
  Several plaque and lesion characteristics have been associated with an increased risk for procedural stroke during or shortly after carotid artery stenting (CAS). While technical advancements in stent design and cerebral protection devices (CPD) may help reduce the procedural stroke risk, and anatomy remains important, tailoring stenting procedures according to plaque and lesion characteristics might be a useful strategy in reducing stroke associated with CAS. In this descriptive report of the ongoing Asymptomatic Carotid Surgery Trial-2 (ACST-2), it was assessed whether choice for stent and use or type of CPD was influenced by plaque and lesion characteristics.
  
  
  METHODS
  Trial patients who underwent CAS between 2008 and 2015 were included in this study. Chi-square statistics were used to study the effects of plaque echolucency, ipsilateral preocclusive disease (90-99%), and contralateral high-grade stenosis (>50%) or occlusion of the carotid artery on interventionalists' choice for stent and CPD. Differences in treatment preference between specialties were also analysed.
  
  
  RESULTS
  In this study, 831 patients from 88 ACST-2 centres were included. Almost all procedures were performed by either interventional radiologists (50%) or vascular surgeons (45%). Plaque echolucency, ipsilateral preocclusive disease (90-99%), and significant contralateral stenosis (>50%) or occlusion did not affect the choice of stent or either the use of cerebral protection and type of CPD employed (i.e., filter/flow reversal). Vascular surgeons used a CPD significantly more often than interventional radiologists (98.6% vs. 76.3%; p < .001), but this choice did not appear to be dependent on patient characteristics.
  
  
  CONCLUSIONS
  In ACST-2, plaque characteristics and severity of stenosis did not primarily determine interventionalists' choice of stent or use or type of CPD, suggesting that other factors, such as vascular anatomy or personal and centre preference, may be more important. Stent and CPD use was highly heterogeneous among participating European centres.
authors.affiliation: Nuffield Department of Surgical Sciences, University of Oxford, Level 6 John Radcliffe Hospital, Oxford OX3 9DU, UK; Department of Vascular Surgery, University Medical Center Utrecht, PO Box 85500, Utrecht, The Netherlands.
authors.forename: D D
authors.initials: DD
authors.lastname: de Waard
authors.affiliation: Nuffield Department of Surgical Sciences, University of Oxford, Level 6 John Radcliffe Hospital, Oxford OX3 9DU, UK. Electronic address: alison.halliday@nds.ox.ac.uk.
authors.forename: A
authors.initials: A
authors.lastname: Halliday
authors.affiliation: Department of Vascular Surgery, University Medical Center Utrecht, PO Box 85500, Utrecht, The Netherlands.
authors.forename: G J
authors.initials: GJ
authors.lastname: de Borst
authors.affiliation: Clinical Trial Service Unit, Nuffield Department of Population Health, University of Oxford, Richard Doll Building, Old Road Campus, Roosevelt Drive, Oxford OX3 7LF, UK.
authors.forename: R
authors.initials: R
authors.lastname: Bulbulia
authors.affiliation: Department of Vascular Surgery, University Medical Center Utrecht, PO Box 85500, Utrecht, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Huibers
authors.affiliation: Department of Surgery, Istituto Auxologico Italiano IRCCS, Via Mercalli 30, 20122 Milan, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Casana
authors.affiliation: Department of Neurology and Stroke Center, University Hospital Basel, CH-4031 Basel, Switzerland.
authors.forename: L H
authors.initials: LH
authors.lastname: Bonati
authors.affiliation: Department of Vascular Surgery, Policlinico di Monza, Via Amati 111, 20900 Monza, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Tolva
mesh_terms: D058070:Asymptomatic Diseases; D016893:Carotid Stenosis / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D002560:Cerebrovascular Circulation; D002561:Cerebrovascular Disorders / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D016009:Chi-Square Distribution; D000066491:Clinical Decision-Making; D057505:Embolic Protection Devices; D016894:Endarterectomy, Carotid; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation*; D006801:Humans; D018579:Patient Selection; D058226:Plaque, Atherosclerotic; D010818:Practice Patterns, Physicians'; D011474:Prosthesis Design; D012307:Risk Factors; D012720:Severity of Illness Index; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome
keywords: Carotid artery stenosis; Carotid artery stenting; Cerebral protection devices; Plaque echolucency; Randomized controlled trial; Stent design