Low Risk of Ipsilateral Stroke in Patients With Asymptomatic Carotid Stenosis on Best Medical Treatment: A Prospective, Population-Based Study

Background and Purpose— The annual risk of ischemic stroke distal to ≥50% asymptomatic carotid stenoses was ≈2% to 3% in early cohort studies and subsequent randomized trials of endarterectomy. This risk might have fallen in recent years owing to improvements in medical treatment, but there are no published prognostic data from studies initiated within the last 10 years. Methods— In a population-based study of all patients with transient ischemic attack (TIA) or stroke in the Oxford Vascular Study, we studied the risk of TIA and stroke in patients with ≥50% contralateral asymptomatic carotid stenoses recruited consecutively from 2002 to 2009 and given intensive contemporary medical treatment. Results— Of 1153 consecutively imaged patients presenting with stroke or TIA, 101 (8.8%) had ≥50% asymptomatic carotid stenoses (mean age, 75 years; 39% women; 40% age ≥80 years). During 301 patient-years of follow-up (mean, 3 years), there were 6 ischemic events in the territory of an asymptomatic stenosis, 1 minor stroke (initially 50% to 69% stenosis), and 5 TIAs (2 initially 50% to 69% stenosis; 3 to 70% to 99% stenosis), 3 of which led to subsequent endarterectomy. The average annual event rates on medical treatment were 0.34% (95% CI, 0.01 to 1.87) for any ipsilateral ischemic stroke, 0% (95% CI, 0.00 to 0.99) for disabling ipsilateral stroke, and 1.78% (95% CI, 0.58 to 4.16) for ipsilateral TIA. Conclusions— In the first study of the prognosis of ≥50% asymptomatic carotid stenosis to be initiated in the last 10 years, the risk of stroke on intensive contemporary medical treatment was low. Larger studies are required to determine whether this apparent improvement in prognosis is generalizable.

[1]  A. Abbott,et al.  Medical (Nonsurgical) Intervention Alone Is Now Best for Prevention of Stroke Associated With Asymptomatic Severe Carotid Stenosis: Results of a Systematic Review and Analysis , 2009, Stroke.

[2]  P A Gaines,et al.  Who benefits most from intervention for asymptomatic carotid stenosis: patients or professionals? , 2009, European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery.

[3]  P. Rothwell,et al.  Temporal trends in the risks of stroke and death due to endarterectomy for symptomatic carotid stenosis: an updated systematic review. , 2009, European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery.

[4]  J. Spence Asymptomatic carotid stenosis: criterion standard should be medical therapy. , 2009, Archives of surgery.

[5]  J. Jenkins,et al.  Sham-feed or sham? , 2009, Archives of surgery.

[6]  Erik Buskens,et al.  Prevalence of Asymptomatic Carotid Artery Stenosis According to Age and Sex: Systematic Review and Metaregression Analysis , 2009, Stroke.

[7]  M. Hennerici,et al.  Atorvastatin Reduces the Risk of Cardiovascular Events in Patients With Carotid Atherosclerosis: A Secondary Analysis of the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) Trial , 2008, Stroke.

[8]  A. Naylor,et al.  Treatment of asymptomatic carotid disease with stenting: con. , 2008, Seminars in vascular surgery.

[9]  Mark H Wholey,et al.  Treatment of asymptomatic carotid disease with stenting: pro. , 2008, Seminars in vascular surgery.

[10]  A. Algra,et al.  Asymptomatic Carotid Artery Stenosis and the Risk of New Vascular Events in Patients With Manifest Arterial Disease: The SMART Study , 2007, Stroke.

[11]  C. Levi,et al.  What Should We Do with Asymptomatic Carotid Stenosis? , 2007, International journal of stroke : official journal of the International Stroke Society.

[12]  P. Rothwell,et al.  Asymptomatic carotid stenosis: what to do , 2007, Current opinion in neurology.

[13]  P. Rothwell,et al.  Risk of Coronary and Other Nonstroke Vascular Death in Relation to the Presence and Extent of Atherosclerotic Disease at the Carotid Bifurcation , 2006, Stroke.

[14]  L. Goldstein,et al.  High-dose atorvastatin after stroke or transient ischemic attack. , 2006 .

[15]  P. Rothwell,et al.  Effect of Nonoptimal Imaging on the Relationship Between the Measured Degree of Symptomatic Carotid Stenosis and Risk of Ischemic Stroke , 2006, Stroke.

[16]  P. Rothwell,et al.  Patient Behavior Immediately After Transient Ischemic Attack According to Clinical Characteristics, Perception of the Event, and Predicted Risk of Stroke , 2006, Stroke.

[17]  E. Minar,et al.  Gender differences in outcome of conservatively treated patients with asymptomatic high grade carotid stenosis. , 2005, Stroke.

[18]  A. Nicolaides,et al.  Severity of asymptomatic carotid stenosis and risk of ipsilateral hemispheric ischaemic events: results from the ACSRS study. , 2005, European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery.

[19]  G. Donnan,et al.  Embolic Signals And Prediction of Ipsilateral Stroke or Transient Ischemic Attack in Asymptomatic Carotid Stenosis: A Multicenter Prospective Cohort Study , 2005, Stroke.

[20]  P. Rothwell,et al.  Carotid endarterectomy for asymptomatic carotid stenosis: asymptomatic carotid surgery trial. , 2004, Stroke.

[21]  曲东锋 Stroke Prevention by Aggressive Reduction in Cholesterol Levels , 2004 .

[22]  S. Gutnikov,et al.  Change in stroke incidence, mortality, case-fatality, severity, and risk factors in Oxfordshire, UK from 1981 to 2004 (Oxford Vascular Study) , 2004, The Lancet.

[23]  R. Peto,et al.  Prevention of disabling and fatal strokes by successful carotid endarterectomy in patients without recent neurological symptoms: randomised controlled trial , 2004, The Lancet.

[24]  R. Collins,et al.  Effects of cholesterol-lowering with simvastatin on stroke and other major vascular events in 20 536 people with cerebrovascular disease or other high-risk conditions , 2004, The Lancet.

[25]  P. Rothwell,et al.  Systematic review of the risks of carotid endarterectomy in relation to the clinical indication for and timing of surgery. , 2003, Stroke.

[26]  Sarah Parish,et al.  MRC/BHF Heart Protection Study of cholesterol-lowering with simvastatin in 5963 people with diabetes: a randomised placebo-controlled trial , 2003, The Lancet.

[27]  S. Gutnikov,et al.  Analysis of pooled data from the randomised controlled trials of endarterectomy for symptomatic carotid stenosis , 2003, The Lancet.

[28]  P. Rothwell,et al.  Interrelation between plaque surface morphology and degree of stenosis on carotid angiograms and the risk of ischemic stroke in patients with symptomatic carotid stenosis. On behalf of the European Carotid Surgery Trialists' Collaborative Group. , 2000, Stroke.

[29]  A. Fox,et al.  Risk factors and outcome of patients with carotid artery stenosis presenting with lacunar stroke , 2000, Neurology.

[30]  D. O'leary,et al.  Asymptomatic internal carotid artery stenosis defined by ultrasound and the risk of subsequent stroke in the elderly. The Cardiovascular Health Study. , 1998, Stroke.

[31]  J. Toole,et al.  The delay in reporting symptoms of carotid artery stenosis in an at-risk population. The Asymptomatic Carotid Atherosclerosis Study experience: a statement of concern regarding watchful waiting. , 1997, Archives of neurology.

[32]  M. Abrahamowicz,et al.  Outcome of asymptomatic patients with carotid disease , 1997, Neurology.

[33]  W S Moore,et al.  Surgical results: a justification of the surgeon selection process for the ACAS trial. The ACAS Investigators. , 1996, Journal of vascular surgery.

[34]  A. Davies,et al.  Endarterectomy for asymptomatic carotid artery stenosis , 1995, BMJ.

[35]  J. Driessen Risk of stroke in the distribution of an asymptomatic carotid artery , 1995, The Lancet.

[36]  Peter M. Rothwell,et al.  RISK OF STROKE IN THE DISTRIBUTION OF AN ASYMPTOMATIC CAROTID-ARTERY , 1995 .

[37]  J. Slattery,et al.  Equivalence of Measurements of Carotid Stenosis: A Comparison of Three Methods on 1001 Angiograms , 1994, Stroke.

[38]  W S Moore,et al.  Efficacy of carotid endarterectomy for asymptomatic carotid stenosis. The Veterans Affairs Cooperative Study Group. , 1993, The New England journal of medicine.

[39]  R. Cuming,et al.  Prevalence, progression and natural history of asymptomatic carotid stenosis: is there a place for carotid endarterectomy? , 1992, European journal of vascular surgery.

[40]  N. Bornstein,et al.  Vascular Risks of Asymptomatic Carotid Stenosis , 1991, Stroke.

[41]  B. Satiani,et al.  Natural history of nonoperated, significant carotid stenosis , 1988, Annals of vascular surgery.

[42]  M. Mcclurken,et al.  Natural history of asymptomatic carotid plaque. Five year follow-up study. , 1987, American journal of surgery.

[43]  D. Wiebers,et al.  The natural history of asymptomatic carotid artery occlusive lesions. , 1987, JAMA.

[44]  M. Hennerici,et al.  Natural history of asymptomatic extracranial arterial disease. Results of a long-term prospective study. , 1987, Brain : a journal of neurology.

[45]  V. Thijs Does surgery have a role in the management of asymptomatic carotid artery stenosis? Yes, but... , 2008, Nature Clinical Practice Neurology.

[46]  K. Welch,et al.  High-dose atorvastatin after stroke or transient ischemic attack. , 2006, The New England journal of medicine.

[47]  P. Rothwell,et al.  Interpretation of operative risks of individual surgeons. European Carotid Surgery Trialists' Collaborative Group. , 1999, Lancet.

[48]  L. Irwig,et al.  The natural history of asymptomatic carotid artery disease. , 1993, Journal of vascular surgery.