Female doctor talking with patient about May-Thurner syndrome

May-Thurner syndrome is a rare vascular condition that can cause symptoms in your left leg or foot and, if left untreated, leads to blood clots and other complications. Find out more about this condition, its symptoms, and how it can be treated.

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What is May-Thurner Syndrome?


Your arteries and veins, also called blood vessels, have an important job to do. Your arteries carry blood from your heart and into the rest of your body, and once your organs and tissues get the oxygen and nutrients they need, your veins carry the blood back to your heart.

In order to work the right way, your blood vessels need to be smooth, flexible, and open, with nothing pressing on or blocking them to limit blood flow.

In May-Thurner syndrome, a nearby artery presses on your left iliac vein, which brings blood from your pelvis and legs back up to your heart. This compression keeps blood from flowing properly and can lead to complications over time.

May-Thurner Syndrome Symptoms

Some people may have no symptoms, but symptoms can include:

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Is May-Thurner Syndrome Dangerous?


In some cases, you may not know you have May-Thurner syndrome until you develop DVT. While DVT is not deadly, if a blood clot breaks free it can travel to your lungs, heart, or brain and lead to life-threatening complications like a pulmonary embolism, heart attack, or stroke.

It’s very important to see a doctor if you have symptoms of DVT, which can include:

  • Leg swelling
  • Leg pain or tenderness
  • Redness or other changes in skin color, or skin that feels warm

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DVT can also lead to a condition called chronic venous insufficiency, where the valves in your veins no longer work properly. This can cause symptoms like:

  • A feeling of heaviness in your leg
  • Swelling
  • Pain
  • Skin changes, including discoloration
  • Ulcers, or open sores that do not heal

Is May-Thurner Syndrome Treatable?


Treatment for May-Thurner will depend on your symptoms and risk factors. Some treatments can include:

  • Blood thinner medicines, which can prevent blood clots
  • Thrombolysis, a catheter-based procedure that delivers clot-busting medicine directly to the site of the blood clot
  • Stenting, a procedure that uses a small tube of metal mesh to open up your vein and restore proper blood flow

In some cases, surgery may be required to bypass the narrowed part of your vein, or to reposition the artery that has compressed your vein. Your vascular surgeon will recommend the best type of treatment based on your specific needs.

To learn more about May-Thurner syndrome, contact the UPMC Division of Vascular Surgery at (412) 802-3333.

About Heart and Vascular Institute

The UPMC Heart and Vascular Institute has long been a leader in cardiovascular care, with a rich history in clinical research and innovation. As one of the first heart transplant centers in the country and as the developer of one of the first heart-assist devices, UPMC has contributed to advancing the field of cardiovascular medicine. We strive to provide the most advanced, cutting-edge care for our patients, treating both common and complex conditions. We also offer services that seek to improve the health of our communities, including heart screenings, free clinics, and heart health education. Find an expert near you.