Page 18 - Virtual Vascular Vol 2 Sep 2020-f

An 82 years old lady with history of hypertension presented with frequent episodes
of debilitating dizziness, associated with repeated exercises of the left upper limb.
Left arm systolic blood pressure was >40mmHg less than right arm.

MR angiogram showed occlusion of left subclavian artery, associated with retrograde
flow of left vertebral artery.

Subclavian Steal Syndrome

• Subclavian steal syndrome is due to retrograde or reversed blood

flow in the vertebral artery because of a proximal stenosis or

occlusion of the subclavian artery

• The arm is supplied by blood down the vertebral artery at the

expense of the vertebra-basilar circulation

• Symptoms range from dizziness to syncope, usually exacerbated

by repeated exercises of the upper limb

• There is a significant differential brachial blood pressure

difference

• Investigations include duplex ultrasound, CT or MR angiography

• Treatment is by endovascular angioplasty/ stent or open bypass

surgery

• Asymptomatic differential upper limb BP difference does not

require treatment

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