Post-Thrombotic Syndrome After DVT: Overview and More

A Long-Term Complication for Some People Who've Had a DVT

Post-thrombotic syndrome (PTS) is a painful condition that happens to some people who have previously had a deep vein thrombosis (DVT), a blockage in one of their veins deep in their body. Post-thrombotic syndrome can cause leg pain, leg ulcerations, and swelling. 

Post-thrombotic syndrome isn’t diagnosed right after you get a DVT. You might be diagnosed with it three months to two years or so after your initial DVT.

This article discusses some of the causes and symptoms of post-thrombotic syndrome as well as its treatment, diagnosis, and related topics. 

Woman with swollen ankles

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Post-Thrombotic Syndrome After a DVT

Post-thrombotic syndrome is a complication experienced by some people who’ve had a DVT. In DVT, a blood clot blocks off some of the blood that is returning to the heart. This can cause symptoms like pain and swelling in the area where the blockage happens. 

Where Does DVT Occur?

Most commonly DVTs occur in the leg, especially your calf. However, it is also possible to get a DVT (and post-thrombotic syndrome) in other parts of your body, like your arm. 

In most people, symptoms of a DVT completely go away within a month or so. However, in some people, it causes more long-term symptoms, called post-thrombotic syndrome. Some of the symptoms following the DVT may never fully go away, and some new ones can appear.

Estimates vary, but between 20% and 50% of people experience post-thrombotic syndrome after having a DVT. About 5% of people have severe symptoms from it. 

Causes of Post-Thrombotic Syndrome 

Post-thrombotic syndrome develops after one or more blood clots block flow in one of your veins. These clots can take a while to go away and, in some cases, the blockage only partly diminishes. 

The initial DVT can cause inflammation that damages valves found inside your veins, the ones that normally keep blood from flowing backward. 

Because of all this, the blood pressure inside the veins of your leg becomes higher than normal. This leads to the symptoms of post-thrombotic syndrome, such as swelling and pain in the calf.

Post-Thrombotic Syndrome Risk Factors

Some people have risk factors that put them at higher risk of getting post-thrombotic syndrome. Some of these are:

  • Very large initial DVT
  • Having another DVT in the same area
  • DVTs closer to your torso (e.g., in the thigh instead of the calf)
  • Obesity
  • Increased age
  • Being a smoker

People who are promptly treated for their initial DVT with anticoagulant medications (blood thinners) are also less likely to eventually develop post-thrombotic syndrome.

Signs and Symptoms

Symptoms of post-thrombotic syndrome can range from mild to severe problems that significantly impact your quality of life. Some potential signs and symptoms include:

  • Leg pain or heaviness
  • Leg swelling
  • Leg redness 
  • Leg skin ulcers
  • Darkening and thickening of the surrounding skin
  • Fatigue with exercise
  • Very prominent veins in the leg

Symptoms might come and go, or they may persist. They may be worse while standing or walking and better while resting and elevating the leg. 

Post-Thrombotic Syndrome Vs. New Blood Clot

Some of the symptoms of post-thrombotic syndrome are similar to those you might experience from a blood clot causing a new DVT (e.g., leg pain and swelling). Sometimes it may be difficult to tell these two conditions apart. 

If you develop post-thrombotic syndrome, you will get a sense of your own regular symptoms. If you are having pain and swelling that is about the same as usual, it’s unlikely that you have a new blood clot. However, if your symptoms have suddenly worsened, you should seek immediate medical treatment. 

If necessary, your healthcare provider can perform further diagnostic tests to see if you have a new DVT that needs treatment. 

When to See a Healthcare Provider with PTS Symptoms

If you have previously had a DVT, you will need regular follow-up care with your healthcare provider. That person can monitor your symptoms as they diminish after your initial DVT. They can also be alert to the possibility of post-thrombotic syndrome and get you diagnosed promptly.

If your leg just hasn’t returned to normal a couple of months after your DVT, bring it to your healthcare provider's attention. Let them know if your symptoms went away but seem to have come back.

Diagnosis

A medical professional diagnoses post-thrombotic syndrome using the person’s complete medical history, including their other medical conditions, their current symptoms, and their clinical exam. Having DVT in the past is a significant indicator of potential post-thrombotic syndrome.

Because the symptoms from an initial DVT can take a while to go away, people aren’t usually officially diagnosed with post-thrombotic syndrome until three to six months have passed. Until then, the symptoms still might be from the initial DVT and not from more permanent changes.  

When Is Post-Thrombotic Syndrome Diagnosed?

Post-thrombotic syndrome is usually diagnosed within a couple of years after a person has had their DVT.

Treatment and Ongoing Management

Unfortunately, there is not an ideal treatment for post-thrombotic syndrome. There aren't good treatments to reverse some of the changes that cause the condition. There is also a lack of good pharmaceutical treatments that help improve symptoms. 

Some clinicians recommend prolonging anticoagulation treatment in people with post-thrombotic syndrome. These medications are initially prescribed in people who have a DVT to stop the clot from getting bigger and prevent it from traveling to the lungs (pulmonary embolism). 

Other healthcare providers sometimes prescribe other pharmaceuticals, like diuretic drugs or drugs that affect the veins, like Defitelio (defibrotide). However, there isn't good evidence that any of these approaches are very helpful. 

Some approaches that may be helpful include:

  • Compression stockings (to promote better blood flow through the leg veins)
  • Mechanized leg compression devices
  • Elevating the legs when seated
  • Moisturizing creams to help with skin dryness and fragility
  • Wound care, including potential antibiotics if needed for ulcers

A medical procedure or surgery (e.g., a venous bypass surgery) may be worth trying in some people with severe post-thrombotic syndrome.

Exercise With Post-Thrombotic Syndrome

Exercise is another important component of managing post-thrombotic syndrome. Although exercise may temporarily worsen your symptoms if you overdo it, it may help reduce your symptoms over time.

Your healthcare provider can work with you to suggest exercises that will be practical for you. These can help you improve your leg strength, flexibility, and overall cardiovascular health. 

Exercise can be particularly helpful if you're overweight. In those instances, a diet promoting weight loss may also help reduce symptoms. 

Summary

Post-thrombotic syndrome is a medical complication that happens in some people who have previously had deep vein thrombosis (DVT). DVT can cause damage to the veins. After one or more blood clots block flow in one of your veins, post-thrombotic syndrome can develop. This can lead to long-term damage to the veins, causing symptoms such as leg pain and swelling.

A diagnosis of post-thrombotic syndrome is often delayed due to the prolonged nature of DVT symptoms. Treatment varies at this point, often incorporating anticoagulation drugs, compression stockings, and, in severe cases, surgery. Exercise and other lifestyle interventions are a cornerstone of prevention. 

A Word From Verywell

Living with a condition like post-thrombotic syndrome can be extremely frustrating. Although your medical team will do all they can to help, your leg may never completely return to normal. By working closely with your team, you’ll figure out the strategies that most improve your quality of life. 

Frequently Asked Questions

  • Does post-thrombotic syndrome ever go into remission?

    The symptoms of post-thrombotic syndrome may diminish with treatment as you find ways to minimize your problems. However, it’s likely that your leg may never be completely as it was before. (In contrast, initial symptoms from a DVT do go away completely in many people within a few weeks.) 

  • Can you improve post-thrombotic syndrome through lifestyle changes?

    Exercise, particularly exercise involving the leg, can improve strength, flexibility, and blood flow to the area. By maintaining a moderate weight, you may also be able to reduce your symptoms. Remembering to elevate your leg and wear your compression devices can also help. 

  • Are airplanes safe with post-thrombotic syndrome?

    Being on a long airplane flight may slightly increase your risk of having another DVT. Although most people with post-thrombotic syndrome can ride in an airplane without problems, it’s a good idea to weigh your particular risks with your healthcare provider. They may suggest things to lower your risk, like wearing compression hose and moving your legs often.
    (Note: In contrast, people who have recently had a DVT are often advised not to travel by airplane for several weeks, due to the risk of a clot breaking free.)

  • Can you qualify for disability with post-thrombotic syndrome?

    Maybe. Some people with post-thrombotic syndrome have severe symptoms that may prevent them from being able to return to their normal work (e.g., severe pain). 
    However, people with milder or waxing and waning symptoms might not qualify. Additionally, people who have a DVT but do not get post-thrombotic syndrome are unlikely to qualify. Your health care provider can connect you with someone who can help you investigate. 

  • Does insurance cover post-thrombotic syndrome care?

    Post-thrombotic syndrome is a well-known medical issue that affects some people who have previously had a DVT. It has its own ICD code for billing, so at least some aspects of care should be covered. Check with your insurance company about the coverage of specific interventions suggested by your healthcare team.  

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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Ruth Jessen Hickman, MD
Ruth Jessen Hickman, MD, is a freelance medical and health writer and published book author.