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Subclavian Steal Syndrome Workup

  • Author: Iman Bayat, MBBS, MRCS; Chief Editor: Vincent Lopez Rowe, MD  more...
Updated: Nov 19, 2015

Approach Considerations

After an adequate physical examination, routine laboratory studies should be ordered to address risk factors for atherosclerosis. These tests should include a fasting lipid profile and blood glucose.

Imaging studies that may be considered include duplex ultrasonography, computed tomography (CT) angiography (CTA), four-vessel cerebral arteriography, and magnetic resonance angiography (MRA), chest radiography, and electrocardiography (ECG).[6] (See Subclavian Steal Syndrome Imaging.)



Duplex ultrasonography is the most important test of the extracranial carotid and vertebral arteries, as well as the subclavian artery. It can demonstrate retrograde blood flow in the vertebral artery and any significant occlusive lesions of the carotid arteries in the neck.

Subclavian steal syndrome is now most commonly diagnosed during Doppler ultrasonographic examination of the neck arteries.[7] In most cases, because of anatomic constraints imposed by the chest wall, it is difficult to assess the proximal subclavian artery adequately by means of ultrasonography.



Searching for significant lesions in the ipsilateral carotid artery is important. If brachial artery pressures are significantly decreased (>20%) compared with the contralateral side, arch aortography should be performed to further define the problem and plan for operative or interventional repair.

Although conventional angiography remains the gold standard investigation for the diagnosis of subclavian occlusive disease in most centers, CTA has replaced this modality as the first-line test. It has a high sensitivity and specificity and has the advantage of being able to identify other lesions in the arch vessels. No arterial puncture is required. However, if endovascular treatment is being considered, conventional four-vessel arteriography is a more appropriate study, in that it allows diagnosis and treatment to be accomplished at the same time.

Four-vessel cerebral arteriography can define the problem anatomically, demonstrating retrograde blood flow in the vertebral artery and associated proximal occlusive subclavian artery lesions. In addition, arteriography serves as a road map for possible repair (surgical vs endovascular) of the subclavian artery.

MRA has become an alternative to conventional angiography for the assessment of subclavian steal syndrome, especially in patients with renal dysfunction. Unfortunately, however, MRA often overestimates the degree of arterial obstruction and is associated with a higher degree of false-positive results.


Other Studies

Chest radiography is performed to look for unusual causes of subclavian artery obstruction (eg, cervical rib).

Because many of these patients have concomitant ischemic heart disease, electrocardiography (ECG) is advisable.

Contributor Information and Disclosures

Iman Bayat, MBBS, MRCS Vascular Surgery Registrar, Austin Hospital, Melbourne, Australia

Iman Bayat, MBBS, MRCS is a member of the following medical societies: Royal College of Surgeons of England, Royal Australasian College of Surgeons

Disclosure: Nothing to disclose.


Jason Chuen, MBBS, PGDipSurgAnat, FRACS(Vasc) Vascular and Endovascular Surgeon, Elgar Hill Medical Suites; Director of Vascular Surgery, Austin Health; Clinical Senior Lecturer, The University of Melbourne, Faculty of Medicine, Dentistry, and Health Sciences

Jason Chuen, MBBS, PGDipSurgAnat, FRACS(Vasc) is a member of the following medical societies: Association for Academic Surgery, Australian Medical Association, Royal Australasian College of Surgeons, Australasian Society for Ultrasound in Medicine, Academy of Surgical Educators, Australia and New Zealand Society of Phlebology, Australia and New Zealand Society of Vascular Surgery, Australian Chinese Medical Association of Victoria, Melbourne Vascular Surgical Association

Disclosure: Nothing to disclose.

Jonathan Fong, MBBS General Surgical Registrar, Austin Health

Disclosure: Nothing to disclose.

Chief Editor

Vincent Lopez Rowe, MD Professor of Surgery, Program Director, Vascular Surgery Residency, Department of Surgery, Division of Vascular Surgery, Keck School of Medicine of the University of Southern California

Vincent Lopez Rowe, MD is a member of the following medical societies: American College of Surgeons, American Heart Association, Society for Vascular Surgery, Vascular and Endovascular Surgery Society, Society for Clinical Vascular Surgery, Pacific Coast Surgical Association, Western Vascular Society

Disclosure: Nothing to disclose.


Jeffrey Lawrence Kaufman, MD Associate Professor, Department of Surgery, Division of Vascular Surgery, Tufts University School of Medicine

Jeffrey Lawrence Kaufman, MD is a member of the following medical societies: Alpha Omega Alpha, American College of Surgeons, American Society for Artificial Internal Organs, Association for Academic Surgery, Association for Surgical Education, Massachusetts Medical Society, Phi Beta Kappa, and Society for Vascular Surgery

Disclosure: Nothing to disclose.

Kenneth E McIntyre Jr, MD Professor of Surgery, Chief, Division of Vascular Surgery, University of Nevada School of Medicine; Chief, Surgical Service, Chief, Vascular Surgery, Veterans Administration of Southern Nevada

Kenneth E McIntyre Jr, MD is a member of the following medical societies: American College of Surgeons, Society for Clinical Vascular Surgery, Society for Vascular Surgery, and Southern Association for Vascular Surgery

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

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Irregular proximal subclavian stenosis.
Retrograde blood flow from left vertebral artery into left subclavian artery in patient with subclavian steal syndrome.
Successful stent treatment of subclavian stenosis, with restored antegrade flow into vertebral artery.
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