Vascular Conditions

Iliac Vein Compression Syndrome

Also known as May-Thurner syndrome (MTS), Vein Compression Syndrome occurs when the left iliac vein is compressed by the right iliac artery. This increases the chances of deep vein thrombosis (DVT) in the left extremity, which is a blood clot that may partially or completely block the flow of blood through the vein.


With mild cases of May-Thurner syndrome, you may not experience any symptoms. However, in more severe cases, symptoms can include:

  • Leg pain and inflammation
  • Blood clots
  • DVT — Deep vein thrombosis


The right iliac artery normally runs over the left, however, sometimes the artery that runs to the right leg compresses the left iliac vein against the spine. This narrows and scars the left iliac vein and results in MTS.


This conditioned can be diagnosed by using the following methods:

  • Ultrasound imaging
  • Computed tomography (CT) scans or magnetic resonance imaging (MRI)
  • Venogram or phlebogram


The goals of treatment are to reduce symptoms and chance of complications. To decide which treatment option is right for you, it is important to discuss potential risks, side effects, and benefits. We will help you understand and prepare for your procedure, as well as help with your recovery.

Most treatments for MTS are actually geared toward addressing the DVT associated with vein compression. Approaches may include:


blood-thinning medication may be prescribed to prevent blood clots.

Catheter-directed thrombolytic therapy

This nonsurgical procedure uses medications, called thrombolytics, to dissolve blood clots. Medicine is delivered by inserting a catheter into the vein and guiding it through the vein to the location of the clot. The time it takes for the blood clot to dissolve can range from a few hours to a few days. In some cases, the narrowed vein may need angioplasty to prevent any future clots from developing.

Angioplasty and stenting

Also a nonsurgical treatment, angioplasty widens the vein after a blood clot has been dissolved. This is done by inflating a small balloon at the tip of the catheter to stretch and open t