Subclavian steal syndrome

Subclavian steal syndrome is rare, but sometimes difficult to diagnose. An arteriosclerotic stenotic plaque at the origin of the subclavian (proximal to the takeoff of the vertebral) allows enough blood supply to reach the arm for normal activity, but does not allow enough to meet higher demands when the arm is exercised. 

When that happens, the arm diverts blood away from the brain by reversing blood flow in the vertebral artery. That is, the increased blood flow needs of the arm are achieved by retrograde flow from the vertebral artery, with resultant decreased brain perfusion and possible CNS symptoms. \

Clinically the patient describes claudication of the arm (coldness, tingling, muscle pain) and posterior neurologic signs (visual symptoms, equilibrium problems) when the arm is exercised. Vascular symptoms alone would suggest thoracic outlet syndrome, but the combination with neurologic symptoms identifies the subclavian steal. Duplex scanning is diagnostic when it shows reversal of flow.

Diagnosis

Duplex scanning is diagnostic when it shows reversal of flow.

Сhest radiograph can aid in assessing for any external compression on the subclavian artery.

CT angiography

Management

Anti-platelet and statin therapy.

Smoking cessation, weight loss, and optimising diabetic control.

Percutaneous angioplasty with or without stenting

Carotid-subclavian bypass or axillo-axillary bypass.