Carotid artery stenosis

Last reviewed: 28 Oct 2023

Last updated: 31 Oct 2019

Stroke is the fifth leading cause of death, and the leading cause of disability in the US. Carotid artery stenosis causes approximately 10% to 15% of all ischemic strokes.

Atherosclerotic plaque in the cervical carotid artery is the most common cause. Plaque disruption and atheroembolization into the intracranial circulation is the most common mechanism for stroke.

The majority of carotid artery stenoses are mild or moderate, and asymptomatic.

Duplex ultrasonography is a commonly used mode of diagnosis; computed tomography angiography or magnetic resonance angiography are alternatives that also help to define the anatomy if intervention is indicated.

Most patients with carotid artery stenosis should receive antiplatelet therapy, and all should receive risk factor modification.

Carotid revascularization of moderate- or high-grade recently symptomatic carotid artery stenosis prevents future stroke.

The benefit of revascularization for asymptomatic stenosis is less certain.

Definition

Carotid artery stenosis is a narrowing of the lumen of the carotid artery. Atherosclerotic plaque in the cervical carotid artery is the most common cause. The unique hemodynamics at the carotid bifurcation predisposes this area to atherosclerosis. The majority of patients have mild- or moderate-sized plaques, while some develop high-grade stenoses. A small percentage of plaques may rupture and embolize to occlude intracranial arteries, causing a transient ischemic attack or stroke, or occlude retinal arteries to cause transient monocular blindness (amaurosis fugax) or retinal strokes.

History and exam

Key diagnostic factors

asymptomatic
cervical bruit
focal neurologic deficit lasting >24 hours (i.e., stroke)
focal neurologic deficit lasting <24 hours (i.e., transient ischemic attack [TIA])

More key diagnostic factors

Other diagnostic factors

transient visual symptoms

Other diagnostic factors

Risk factors

older age
history of hypertension
smoking
history of cardiovascular disease
history of hypercholesterolemia

More risk factors

Diagnostic investigations

1st investigations to order

duplex ultrasonography
computed tomography angiography (CTA) of head, neck, and chest

More 1st investigations to order

Investigations to consider

magnetic resonance angiography (MRA) of head, neck, and chest
cervical angiography
CT brain
MRI brain

More investigations to consider

Treatment algorithm

ACUTE

asymptomatic carotid stenosis <70%

asymptomatic carotid stenosis ≥70%: good surgical candidate

asymptomatic carotid stenosis ≥70%: poor surgical candidate

symptomatic

ONGOING

bilateral carotid stenosis

carotid restenosis

Contributors

Authors

Martin M. Brown, MA, MD, FRCP

Professor of Stroke Medicine

UCL Stroke Research Centre

Department of Brain Repair and Rehabilitation

UCL Queen Square Institute of Neurology

University College London

London

Disclosures

MMB received a project grant from the Stroke Association to support the European Carotid Surgery Trial-2; he is also an author of references cited in this topic.

Acknowledgements

Professor Martin M. Brown would like to gratefully acknowledge Dr Brajesh K. Lal, the previous contributor to this topic.

Disclosures

BKL is an author of references cited in this topic.

Peer reviewers

Seemant Chaturvedi, MD, FAAN, FAHA, FANA, FESO

Stewart J. Greenebaum Endowed Professor of Stroke Neurology

Director, Comprehensive Stroke Program

Vice-Chair for Strategic Operations

Department of Neurology

University of Maryland School of Medicine

Baltimore

Disclosures

SC declares that he is an executive committee member of the CREST-2 study.

Mark A. Adelman, MD

Professor and Chief

Vascular and Endovascular Surgery

NYU Langone Medical Center

New York

Disclosures

MAA declares that he has no competing interests.

Jeffrey E. Indes, MD, FACS

Assistant Professor of Surgery and Radiology

Yale University School of Medicine

New Haven

Disclosures

JEI declares that he has no competing interests.

Jonathan D. Beard, ChM, Med, FRCS

Professor of Surgical Education

Consultant Vascular Surgeon

Sheffield Vascular Institute

Sheffield

Disclosures

JDB declares that he is on the Steering Committee of ICSS and ECST-2 Trials.

Ross Naylor, MBBS

Professor of Vascular Surgery

Vascular Surgery Group

Division of Cardiovascular Sciences

Leicester Royal Infirmary

Disclosures

RN declares that he has no competing interests.

Christos D. Liapis, MD, PhD, FACS, FRCS, FEBVS

Professor of Vascular Surgery

Head, Department of Vascular Surgery

Athens Medical Center

Athens

Greece

Disclosures

CDL declares that he has no competing interests.

Differentials
- Carotid dissection or subintimal hematoma
- Thrombotic occlusion of the carotid artery resulting from plaque rupture
- Fibromuscular dysplasia
More Differentials
Guidelines
- Screening for asymptomatic carotid artery stenosis
- Guidelines for the prevention of stroke in patients with stroke and transient ischemic attack
More Guidelines
Patient leaflets
Carotid artery stenosis: what is it?
Carotid artery stenosis: what treatments work?
More Patient leaflets
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Carotid artery stenosis

Summary

Definition

History and exam

Key diagnostic factors

Other diagnostic factors

Risk factors

Diagnostic investigations

1st investigations to order

Investigations to consider

Treatment algorithm

asymptomatic carotid stenosis <70%

asymptomatic carotid stenosis ≥70%: good surgical candidate

asymptomatic carotid stenosis ≥70%: poor surgical candidate

symptomatic

bilateral carotid stenosis

carotid restenosis

Contributors

Authors

Martin M. Brown, MA, MD, FRCP

Disclosures

Acknowledgements

Disclosures

Peer reviewers

Seemant Chaturvedi, MD, FAAN, FAHA, FANA, FESO

Disclosures

Mark A. Adelman, MD

Disclosures

Jeffrey E. Indes, MD, FACS

Disclosures

Jonathan D. Beard, ChM, Med, FRCS

Disclosures

Ross Naylor, MBBS

Disclosures

Christos D. Liapis, MD, PhD, FACS, FRCS, FEBVS

Disclosures

Differentials

Guidelines

Patient leaflets

Log in or subscribe to access all of BMJ Best Practice

Log in or subscribe to access all of BMJ Best Practice

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