Axillo-Subclavian Vein Thrombosis | Thoracic Outlet Syndrome |MedStar Health

A condition caused by repetitive arm motion

This condition, also known as Paget-Schroetter syndrome, develops when a rib or a nearby muscle presses on the axillary vein in the armpit or the subclavian vein in front of the shoulder. This rare condition is a type of thoracic outlet syndrome (TOS) caused by repetitive arm motion, particularly in athletes.

Repeated compression causes the vein to become inflamed and fibrous tissue to build up. This tissue causes the vein to narrow and restrict blood flow, leading to the formation of blood clots.

Left untreated, axillo-subclavian vein thrombosis can cause:


Symptoms can be vague until the vein is fairly blocked. At that time, you may experience:

  • Bluish skin color
  • Heaviness of the arm
  • Muscle bulk that doesn’t match the other arm
  • Swelling and pain in the arm


Who is at risk for axillo-subclavian vein thrombosis?

The condition can affect anyone, but you are at increased risk if you:

  • Participate in sports that require repetitive arm and shoulder motions, such as baseball, softball, basketball, hockey, swimming, tennis, and weightlifting.
  • Work in occupations that involve repetitive use of the arm, such as construction work, house painting, or window washing.
  • Have a blood clotting disorder

  • Have a central venous catheter in the subclavian vein, such as for chemotherapy or hemodialysis
  • Have a pacemaker or defibrillator, because the wires pass through the area


Angiogram (Angiography)

An angiogram is a special X-ray taken as a special dye is injected through a thin, flexible tube called a catheter to detect blockages or aneurysms in blood vessels.

Chest X-ray

Chest X-rays use a small dose of radiation to create pictures of the structures inside the chest, including the lungs, heart, and chest wall.

Computerized Tomography (CT) Scan

The cardiac computed tomography scan, or cardiac CT, uses X-rays to create three-dimensional images of your heart and blood vessels.

Magnetic Resonance Imaging (MRI)

Magnetic resonance imaging, better known as cardiac MRI, is a combination of radio waves, magnets, and computer technology to create images of your heart and blood vessels.

In the early stages, medication may be successful to dissolve clots (thrombolysis). In some cases, surgery may be recommended to restore blood flow or to remove the rib or muscle causing the problem.

Thoracic Outlet Decompression

Learn how MedStar Health’s Heart & Vascular Institute uses thoracic outlet decompression to treat thoracic outlet syndrome.

Additional information

Cardiac rehabilitation

Recover faster and improve your quality of life after heart disease or treatment with help from our exercise physiologists, physical therapists, and dietitians.


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