subclavian steal syndrome is an uncommon condition characterised reduced arterial supply to the opposite arm or carotids/vertebrals when the affected arm is exercised
this occurs when the subclavian artery is impinged or occluded and supply to the arm is retrograde down the ipsilateral vertebral artery which “steals” it from the controlateral vertebral artery
Clinical features
signs of arterial insufficiency of affected arm may be present
BP lower in affected arm compared to contraleral arm