title: Asymptomatic carotid artery stenosis: identification of subgroups with different underlying plaque characteristics.
abstract: OBJECTIVE
  Optimal surgical treatment of patients with asymptomatic carotid artery stenosis (ACAS) remains a matter of debate. Established definitions of ACAS include: (1) patients who never suffered from ipsilateral cerebrovascular events (group 1) or (2) patients who suffered from ipsilateral cerebrovascular events more than 6 months prior to revascularisation (group 2). Cerebrovascular symptoms are closely related to underlying carotid plaque composition and therefore we investigated potential plaque differences between these definition-based subgroups.
  
  
  METHODS
  Cross-sectional analysis of a longitudinal prospective biobank study.
  
  
  METHODS
  Carotid atherosclerotic plaques from 264 asymptomatic patients were harvested during endarterectomy, and subjected to histopathological examination. Patients were divided into two groups: group 1: truly asymptomatic (n = 182), and group 2: patients with ipsilateral events more than 6 months before carotid endarterectomy (CEA) (n = 82).
  
  
  RESULTS
  Patients in group 1 had relatively more stable plaque characteristics as compared with patients in group 2, with a higher median plaque smooth muscle cell content (2.1 (0.0-18.7) vs. 1.6 (0.0-14.4); P = 0.036), a higher proportion of heavily calcified plaques (67.7% (123/182) vs. 48.8% (40/82); P = 0.005) and less frequently intraplaque haemorrhages (11.5% (21/182) vs. 30.5% (25/82); P = 0.001).
  
  
  CONCLUSIONS
  Different plaque characteristics within subgroups of ACAS patients can be identified based on reported past ipsilateral events, which might result in adjusted future treatment strategies.
authors.affiliation: Department of Vascular Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: G W
authors.initials: GW
authors.lastname: van Lammeren
authors.forename: A G
authors.initials: AG
authors.lastname: den Hartog
authors.forename: G
authors.initials: G
authors.lastname: Pasterkamp
authors.forename: A
authors.initials: A
authors.lastname: Vink
authors.forename: J-P P M
authors.initials: JP
authors.lastname: de Vries
authors.forename: F L
authors.initials: FL
authors.lastname: Moll
authors.forename: G J
authors.initials: GJ
authors.lastname: de Borst
mesh_terms: D000368:Aged; D058070:Asymptomatic Diseases; D002339:Carotid Arteries / Q000473:pathology*; D016893:Carotid Stenosis / Q000145:classification / Q000150:complications / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D016894:Endarterectomy, Carotid; D005260:Female; D006470:Hemorrhage / Q000473:pathology; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000473:pathology; D009426:Netherlands; D017711:Nonlinear Dynamics; D058226:Plaque, Atherosclerotic / Q000145:classification / Q000150:complications / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D020521:Stroke / Q000209:etiology; D016019:Survival Analysis; D013997:Time Factors; D014015:Tissue Banks; D061205:Vascular Calcification / Q000473:pathology