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May-Thurner Syndrome

May-Thurner syndrome is a rare vascular disorder in which an artery compresses a vein in your pelvis. This compression can cause symptoms in your left or right leg and foot and may lead to blood clots.

At the UPMC Division of Vascular Surgery, we take a team approach to diagnose and treat your condition.

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What Is May-Thurner Syndrome?

May-Thurner syndrome is a rare vascular condition that affects a vein in your pelvis.

It occurs when a nearby artery compresses the left iliac vein. This vein brings blood from your pelvis and legs back up to your heart.

The compression prevents blood from flowing properly, leading to narrowing and scarring.

In some cases, an artery can compress the right iliac vein, or both veins.

May-Thurner syndrome complications

Some people with May-Thurner syndrome have no symptoms, but over time, this condition can lead to:

  • Leg swelling.
  • Chronic venous insufficiency, in which blood pools in your veins. This causes swelling, pressure, skin changes, and venous ulcers or sores that don't heal.
  • Deep vein thrombosis (DVT), a blood clot in a vein deep below your skin.
    If a blood clot breaks free and travels to your lungs, heart, or brain, it can lead to serious, even life-threatening issues like:

May-Thurner Syndrome Symptoms and Diagnosis

Symptoms of May-Thurner syndrome

Symptoms can include:

  • Swelling, heaviness, or fullness in your leg or foot.
  • Venous ulcers or sores that do not heal on your leg.
  • Varicose veins in your leg.

In some cases, May-Thurner syndrome has no symptoms and patients go undiagnosed until they develop deep vein thrombosis (DVT).

Symptoms of DVT can include:

  • Leg swelling.
  • Leg pain and tenderness.
  • Redness or other changes in skin color.
  • Skin that feels warm.

Diagnosing May-Thurner syndrome

To diagnose May-Thurner syndrome, your doctor will:

  • Perform a physical exam.
  • Ask about your medical history and symptoms.
  • Use an imaging test — like an ultrasound, MRI, or venogram — to confirm your diagnosis.

May-Thurner Syndrome Treatment

May-Thurner syndrome is treatable.

Your treatment will depend on your symptoms and risk factors.

Some treatments for May-Thurner syndrome can include:

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

In some cases, you may need surgery to either:

  • Bypass the narrowed part of your vein.
  • Or reposition the artery so it no longer compresses your vein.