Interventional Therapies to Treat Blood Clots and Their Complications
The Potential Impact of Deep Vein Thrombosis
A blood clot in one of the large veins, usually in a person’s leg or arm, is called a deep vein thrombosis or DVT. When a DVT forms, it can partially or completely block the flow of blood through the vein.
If a DVT is not treated, it can move or break off and travel to the lungs. A blood clot in the lungs – called a pulmonary embolism or PE – is life-threatening.
In addition, when a clot in the deep veins is very extensive or does not dissolve, it can result in a chronic or long-lasting condition called post-thrombotic syndrome (PTS), which causes chronic swelling and pain, discoloration of the affected arm or leg, skin ulcers, and other long-term complications. Learn more about PTS here.
Blood Clot Treatment: Deep Vein Thrombosis
Standard DVT Treatment
There are numerous options for treating blood clots, depending on a person’s individual blood clot diagnosis or medical need. The initial treatments for DVT commonly include anticoagulant medications, referred to as “blood thinners,” and compression stockings.
These types of treatments help to prevent blood clots in the deep veins from growing larger or moving to the lungs and causing a life-threatening PE. While these treatments don’t remove or break down clots, they can keep clots from growing and stop new ones from forming, which provides the body with the time it needs to gradually dissolve existing blood clots.
Interventional DVT Treatment Options
There are times, however, when more aggressive treatment is needed, such as when a DVT is very large, blocks major veins, or produces severe pain and swelling of the limb. With cases such as these, interventional treatment or minimally invasive surgery may sometimes be helpful in reducing the severity of symptoms. These interventional treatments also can be used when a person diagnosed with a DVT does not respond well to anticoagulation therapy or compression stockings.
Interventional treatments for DVT – which are performed in a hospital setting by vascular surgeons and interventional radiologists – are not without risk. They should be considered on a case-by-case basis as a means to reduce early DVT symptoms or reduce the potential severity of PTS. People diagnosed with DVT may be a candidate for interventional treatment when they have:
- A large clot
- A clot at or above the groin
- DVT symptoms (typically pain and/or swelling) are significant, started recently, and are not improving with the initial use of blood-thinning drugs
- A low risk for bleeding
If you have been diagnosed with a DVT, it is important that you follow your healthcare provider’s instructions, and take anticoagulation medication and wear compression stockings as prescribed.
If you learn that you have a large clot, or experience severe symptoms when you are diagnosed, you can ask your healthcare provider if you might be a good candidate for interventional treatment.
Understanding Interventional DVT Treatment Options
There are different interventional procedures that may help relieve DVT symptoms and reduce a person’s risk for long-term complications, such as PTS.
Thrombolytic therapy or catheter-directed thrombolysis
For people diagnosed with a recently-formed, very large DVT, their healthcare provider may suggest an interventional treatment called catheter-directed thrombolysis, which is also known as clot-busting treatment. Such a clot-busting treatment or procedure uses medications to dissolve clots quickly and restore blood flow.*
This clot busting treatment can be done by various methods: The clot-busting drug can be slowly infused into the blood clot, or it can be quickly delivered into the blood clot by a catheter-based device.
With each treatment, a physician makes a small incision to access a leg or other vein under ultrasound guidance. Guided by live X-rays, a catheter or thin plastic tube is inserted through the vein to the DVT site.
Thrombectomy, Angioplasty, Stent Placement
In addition, a physician may sometimes use other clot removal treatments, with or without the use of thrombolytic or clot-busting therapy, including:
- Mechanical thrombectomy (clot removal) devices to mechanically break up the clot into smaller pieces and remove the clot pieces
- Angioplasty, in which a balloon is inserted into the vein containing the DVT and expanded in order to open up blood flow through the vein
- Placement of a stent, which is a tiny, expandable tube that props open the vein and prevents it from narrowing again*
The medical care team will monitor the effectiveness of these clot removal treatments by using imaging, such as ultrasound, computerized tomography (CT) scan, and/or venogram (an x-ray test that involves injecting contrast material into a vein to show how blood flows through veins).
Angioplasty and stents also can be used to treat people with a chronic or older DVT and severe PTS. By opening up the vein, the angioplasty and stents are believed to reduce congestion and improve symptoms.
Potential Risk Factors
The risks associated with the interventional treatment of blood clots include:
- Damage to the vein at the site of the blood clot
- Reaction to anesthesia
- Detaching of a stent
- Excess bleeding that can be severe enough to cause death, which is of greatest concern if clot-busting drugs are used
- The blood clot can form again
A person who undergoes any of these interventional treatments should be aware of these risks and contact the physician who performed the procedure if they experience:
- Swelling or pain that gets worse
- Fluid or blood leaking from the incision site
- Bleeding anywhere on the body
- Weakness, pain, or numbness in the area of the incision
For people diagnosed with a DVT who are unable to take anticoagulation therapies, a filter may be placed into the inferior vena cava (IVC), which is the large vein that carries deoxygenated blood from the lower and middle body into the heart. The filter is used to catch blood clots that move from the lower body and prevent them from entering the lungs and causing a dangerous PE. Some filters are retrievable and some are permanently implanted.
You may be a potential candidate for an IVC filter if you are diagnosed with a DVT or PE and any of the following criteria apply to you:
- Unable to take blood thinners
- Complications, such as bleeding due to anticoagulant therapy
- Recurrent PE despite anticoagulation therapy
- Undergoing chest surgery to remove a clot (pulmonary embolectomy)
However, experts advise that filters not be routinely used among people who can receive anticoagulation therapy, because the use of filters can cause new clots to form. Also, while rare, filters can break, be badly positioned, or move to other areas within the bloodstream.
It’s important for people who have an IVC filter implanted to follow-up regularly with their healthcare providers for re-evaluation and to plan for the removal of the filter when appropriate.
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Vedantham, S., Piazza, G., Sista, A. K., & Goldenberg, N. A. (2016). Guidance for the use of thrombolytic therapy for the treatment of venous thromboembolism. Journal of Thrombosis and Thrombolysis, 41(1), 68–80. doi:10.1007/s11239-015-1318-z
This educational opportunity was funded by an unrestricted educational grant from Boston Scientific.
*The U.S. Food & Drug Administration has not approved thrombolytic or clot-busting drugs, or stents, for the treatment of deep vein thrombosis (DVT). Physician use of thrombolytic or clot-busting drugs and stents to treat DVT is considered on a case-by-case basis, and done off-label when deemed to have potential clinical benefit for a patient. Patients should always discuss with their doctor the risk factors associated with any drug therapy or medical procedure being considered or recommended for them.