Subclavian Artery

What is the subclavian artery?

Your subclavian arteries move oxygen-rich blood from your heart to your upper body. Your left and right subclavian arteries, located below each of your collarbones, are major suppliers of blood to your neck, head and arms.

What does the subclavian artery do?

Your subclavian arteries get oxygenated blood from your heart to your head, neck and arms.

• The first section of each subclavian artery supplies blood to your chest, thyroid and circle of Willis (your brain’s blood supplier).
• The second section of each subclavian artery sends blood to your costocervical trunks, which are in your neck.
• The third section of each subclavian artery, farthest from where it starts, gets blood to your arms. This includes your biceps, triceps, shoulder muscles and forearm muscles.

Where is the subclavian artery located?

Both subclavian arteries are below your clavicles (collarbones), but your left and right subclavian arteries start in different places.

Your right subclavian artery starts at your brachiocephalic artery.

Your left subclavian artery starts at your aortic arch.

Both subclavian arteries travel away from the middle of your body, between your anterior and middle scalene muscles. They extend to your first rib, where they become axillary arteries.

Your subclavian arteries branch off into your left and right:

• Vertebral arteries, which send blood to parts of your brain, as well as your brainstem. These arteries are usually 3 millimeters to 5 mm in diameter.
• Internal thoracic arteries, which get blood to a number of body parts, including your: pericardium (outer lining of your heart), breast, diaphragm and parts of your chest wall and belly wall. These arteries are about 2 mm in diameter. Healthcare providers often use the left internal thoracic artery for coronary artery bypass grafts.
• Dorsal scapular arteries, both of which deliver blood to your upper back muscles to support your arms and shoulders.
• Thyrocervical trunk, which runs up each side of your neck, supplying blood to your neck and shoulders.
• Costocervical trunk, which is on each side of your neck and sends blood to your arms, neck and head.

How big is the subclavian artery?

Your subclavian artery is about .7 centimeters to 1.0 cm (less than half an inch) in diameter.

What is the subclavian artery made of?

Like other blood vessels, your subclavian artery has three layers. Thin, flexible layers of cells make up the inside and outside layers. They surround a middle layer of muscle.

What are the common conditions and disorders that affect the subclavian artery?

Several diseases can affect your subclavian artery, including:

• Atherosclerosis, usually from plaque (fat and cholesterol), can cause a blockage in your artery.
• Thoracic outlet syndrome causes stenosis (narrowing) of your artery, limiting blood flow and affecting your arms.
• Takayasu’s arteritis, a type of vasculitis, can cause inflammation in your subclavian artery and a lack of oxygen to your head and neck or arms.
• Subclavian steal syndrome (usually from atherosclerosis) causes stenosis (narrowing) and takes some of the blood flow meant for your brain and “steals” or diverts it to your arm.

Common signs or symptoms of subclavian artery conditions

Symptoms vary depending on the disease affecting your subclavian artery. Symptoms include:

• A lower blood pressure reading in one arm compared to the other.
• Discoloration in your arm or hands.
• Numbness, tingling, weakness or pain in your arm.
• Swelling.
• Sensitivity to cold in your hands.
• Dizziness.
• Fever.
• Fainting.

Common tests to check the health of the subclavian artery

Your healthcare provider may do these tests:

• Check your blood pressure in both arms.
• Vascular ultrasound.
• Chest X-ray.
• CT scan.
• Magnetic resonance imaging (MRI).
• Addison maneuver (stretch your scalene muscle to check for a radial pulse that’s harder to detect) to check for thoracic outlet syndrome.
• Angiogram (rarely).

Common treatments for the subclavian artery

Healthcare providers use treatments to open up your subclavian artery when it’s narrow or has a blockage. Treatments include:

Subclavian artery disease (atherosclerosis)

• Aspirin and cholesterol-lowering medications.
• Angioplasty to push plaque against the side of your artery wall. After angioplasty, your provider can put in a stent to keep your artery open.
• Surgery to bypass blood flow around the blockage.

Thoracic outlet syndrome

• Physical therapy.
• Nonsteroidal anti-inflammatory drugs (NSAIDs).
• Thrombolytics or “clot-busting” drugs.
• Anticoagulants to prevent blood clots.
• Surgery to fix what’s compressing your artery.

Takayasu’s arteritis

• Corticosteroids.
• Immunosuppressive drugs.
• Surgery or angioplasty to open your artery.

Subclavian steal syndrome

• Antiplatelet therapy to prevent blood clots.
• Anticoagulants to keep blood clots from forming.
• Bypass surgery or angioplasty.

Simple lifestyle changes/tips to keep the subclavian artery healthy

You can care for your subclavian artery like you would for the rest of your cardiovascular system.

• Manage your blood pressure and cholesterol levels.
• Don’t use tobacco products.
• Get regular physical activity.
• Stay at a healthy weight.

A note from Cleveland Clinic

Your subclavian arteries play an important part in making sure your upper body has the blood supply it needs. Eating healthy foods and exercising will help your subclavian arteries stay strong, along with all of your other blood vessels. Regular checkups with your healthcare provider can alert them to any issues that may develop with your circulatory system. If you find yourself with a narrowing artery, treatments are available.