Deep vein thrombosis (DVT) is a blood clot in one of the deep veins in your body, often in the legs. The clot can cause swelling and pain, and it could block blood flow in your leg. Sometimes a clot breaks free and travels to the lungs, which is called pulmonary embolism (PE). PE can be very serious.
Blood thinners help to prevent PE, but they can't stop damage to your veins from clots. That damage can lead to permanent venous insufficiency, when blood can't flow from your leg vein back to your heart. A DVT can also cause post-thrombotic syndrome -- long-term pain, swelling, and sores in your leg.
Sometimes you need more than medicine to treat DVT. If the clot is big, you have a lot of symptoms, or you're at high risk for PE, your doctor might recommend endovascular therapy.
What Is Endovascular Therapy?
Endovascular treatments work inside your veins to remove the clot and prevent blood vessel damage. Usually you'll get these treatments in the first 10 to 14 days after the clot forms.
There are a few types of endovascular therapy. Each one treats DVT in a different way.
Percutaneous Transcatheter Treatments
This is the umbrella term for treatments that place a thin tube called a catheter into your vein to treat DVT. Percutaneous means the procedure is done through a small opening in your skin.
Your doctor can pass different things through the catheter to break up the clot and restore blood flow through the vein:
Venous Thrombolysis, or Catheter-Directed Thrombolysis (CDT)
This minimally invasive procedure is done in an interventional radiology suite or operating room. You'll first get medicine to relax you and prevent pain.
The surgeon makes a small cut in your skin and places a thin tube called a catheter into a vein in your groin, neck, or behind your knee. Contrast dye and X-ray or ultrasound pictures help the doctor find the clot.
Then the doctor places medicine or small devices into the catheter to break up the clot. The medicine drips into your blood vessel slowly over a few hours or days. Most clots dissolve within 24 hours, but some can take up to 3 days to dissolve.
After the catheter comes out, you won't need stitches to close the opening because it's so small. You might go home the same day as the procedure or stay in the hospital for a few days.
Keep taking blood thinners and wear compression stockings for as long as your doctor suggests to prevent new clots from forming. How long you take these medicines depends on what caused the blood clot.
Possible risks from this procedure include:
- Movement of the clot into the lungs (PE)
- Allergic reaction
Pharmacomechanical Thrombectomy (PMT)
In PMT, the doctor makes a small cut in your skin. Then they’ll thread a catheter through the opening to your blood vessel. A device such as a tiny wire coil or suction machine inserted through the catheter breaks up and removes the blood clot.
PMT works faster than CDT. But you will likely have to keep taking a blood thinner and wear compression stockings afterward to keep the vein open.
After PMT, little pieces of the clot may still be inside your blood vessel. There is a small risk that some of those pieces could travel to your lung and cause a PE.
You may need a second procedure to take out the pieces. One option is to suck them out through the catheter, which is called aspiration. Another way to remove the pieces of clot is with balloon angioplasty.
Angioplasty and Stenting
Angioplasty and stenting are often done to open up blocked arteries and prevent heart attacks in people with narrowed arteries called atherosclerosis. These procedures also widen veins that DVT has narrowed.
A specialist called an interventional cardiologist performs angioplasty and stenting. An imaging scan such as an ultrasound helps the doctor find the blockage.
First the doctor inserts a needle into a vein in your groin or behind your knee, depending on where the clot is located. Then they thread a catheter with a balloon on the end into the blocked blood vessel, using an X-ray to guide them to the narrowed spot. Inflating the balloon widens the narrowed blood vessel so blood can flow through it.
If you're getting a stent, the doctor will remove the balloon and insert a metal or plastic tube called a stent into the vein. The stent pushes against your blood vessel walls to hold them open. The doctor may use a device called a stent retriever to grab the clot and remove it.
Inferior Vena Cava (IVC) Filter
If there's a chance that the blood clot might break free, your doctor can use angioplasty to place an inferior vena cava (IVC) filter inside the IVC. This is the main vein in your belly that sends blood from your legs up to your heart. The filter will catch any blood clots that do escape before they can reach your lungs or heart.
After the Procedure
During follow-up visits with your doctor you may have imaging tests to check that your blood vessels are still open. In between these visits, call your doctor if you have symptoms like these:
- Swelling or pain that gets worse
- Weakness or numbness
- Fluid or blood leaking from the surgery site