Signs and Symptoms of May-Thurner Syndrome

Visual representation of a blood clotAlso known as the Iliac Vein Compression Syndrome and Crockett’s Syndrome, the May-Thurner Syndrome is an uncommon vascular condition that increases a person’s chance of developing blood clots.

This is due to the narrowing of the left iliac vein – the vein responsible for bringing blood from the left leg leading to the heart. If left undiagnosed and untreated, a deep vein thrombosis (DVT) or a blood clot can develop in the left leg.


This condition occurs when the right common iliac artery or the artery found in the right leg compresses the vein that runs alongside it, the left iliac vein.

Because the right common iliac artery is usually over the left iliac vein, this leads to the left iliac vein becoming scarred from being pressed against the spine and is narrowed due to the overlying pressure.


Due to the narrowed, and in some cases, scarred left iliac vein, a common May-Thurner symptom, DVT may occur. Most patients experience leg pain and swelling even if the patient undertakes no extreme activity.

This is because the blood flow is blocked and cannot pass through from the left leg to the heart properly. May-Thurner Syndrome signs or symptoms include reddening of the skin and discomfort in the left leg.


In cases where it forms a blood clot, it is possible for the clot to break off and travel to different areas, and most likely end up in the lung.

A pulmonary embolism occurs and is now a medical emergency. Its symptoms include chest pain, shortness of breath, a rapid increase in heartbeat, fainting, and coughing up blood.

The May-Thurner syndrome is not a genetic condition, and therefore, could undergo detection once the left iliac vein suffers compression. Treatments for this condition focus on keeping the vein in its proper shape by using stents.