[Skip to Content]
[Skip to Content Landing]
April 20, 2009

Asymptomatic Carotid Stenosis: Criterion Standard Should Be Medical Therapy

Arch Surg. 2009;144(4):382-383. doi:10.1001/archsurg.2009.16

Both the recent article and accompanying commentary1 regarding carotid endarterectomy as the criterion standard for revascularization missed the point. Nearly half the patients in the study were asymptomatic. For most of them, revascularization was unwarranted. Transcranial Doppler embolus detection has been shown to identify patients with carotid stenosis who are at higher risk.2,3

We reported in 20054 that transcranial Doppler embolus detection was extremely effective at identifying which patients with asymptomatic carotid stenosis may benefit from revascularization. Only 10% of our patients had microemboli, and their 1-year risk of stroke was 15.6%, so they would probably benefit from revascularization. However, the 90% of patients with asymptomatic carotid stenosis without microemboli had only a 1% risk of stroke, with a very tight 95% confidence interval: 1.01% to 1.36%. They cannot benefit unless the procedure can be done with a risk of less than 1%.

Thus, even the commendable surgical results reported by Suliman et al1 carry more than twice the risk of medical therapy. Patients with asymptomatic carotid stenosis are better off with medical therapy unless they have microemboli on transcranial Doppler. In recent years, with more intensive medical therapy, this now represents less than 5% of patients. The criterion standard for patients with asymptomatic carotid stenosis is neither carotid endarterectomy nor stenting: it is intensive medical therapy.

Correspondence: Dr Spence, Stroke Prevention & Atherosclerosis Research Centre, Robarts Research Institute, 1400 Western Rd, London, ON N6G 2V2, Canada (dspence@robarts.ca).

Financial Disclosure: None reported.

Suliman  AGreenberg  JChandra  ABarillas  SIranpour  PAngle  N Carotid endarterectomy as the criterion standard in high-risk elderly patients.  Arch Surg 2008;143 (8) 736- 742PubMedGoogle ScholarCrossref
Molloy  JMarkus  HS Asymptomatic embolization predicts stroke and TIA risk in patients with carotid artery stenosis.  Stroke 1999;30 (7) 1440- 1443PubMedGoogle ScholarCrossref
Markus  HSMackinnon  A Asymptomatic embolization detected by Doppler ultrasound predicts stroke risk in symptomatic carotid artery stenosis.  Stroke 2005;36 (5) 971- 975PubMedGoogle ScholarCrossref
Spence  JDTamayo  ALownie  SPNg  WFerguson  GG Absence of microemboli on transcranial Doppler identifies low-risk patients with asymptomatic carotid stenosis [published online ahead of print October 13, 2005].  Stroke 2005;36 (11) 2373- 2378PubMedGoogle ScholarCrossref