The Doctor Recommended Guide to Understanding Post-Thrombotic Syndrome

What is Post-Thrombotic Syndrome?

Post-thrombotic syndrome, or PTS, is a serious and painful condition that can last a long time. It occurs because of deep vein thrombosis (DVT). The veins found in your legs and arms have small valves inside that help ensure the blood flows in the proper direction, back to the heart. If DVT occurs, it means there is a clot or blockage in the way of the valve, which blocks the proper blood flow, resulting in severe damage to the valves.

Over a third of people with DVT will develop PTS. Symptoms of this include ulcers, chronic leg pain, swelling, and redness. Over time, PTS can affect a person’s mobility and can be costly to treat. That is why taking preventative steps is so important. DVT most commonly occurs in the legs.

Population and Demographics and Risk Factors

Post-thrombotic Syndrome is a condition that affects around 50% of people who have had a deep vein thrombosis, or DVT, or the legs.

Risk factors for post-thrombotic syndrome are still being studied but there are some criteria we can use to help predict who is most at risk. Some of those criteria include:

  • Being significantly overweight or obese
  • DVT that occurs above the knee (thigh or groin)
  • No treatment, late treatment, or incomplete treatment of DVT
  • BMI > 35
  • A history of multiple DVT’s
  • Older age
  • Pre-existing vein disease like venous insufficiency and varicose veins

Along with the issues mentioned above, that can increase your risk of developing PTS; it is also fairly common in individuals over 65. It can also happen in both women and men.

Causes of the Disease

The leading cause of PTS is the valves or walls of the veins being damaged because of a DVT. Receiving prompt diagnosis and treatment for a DVT is needed to help prevent this damage from occurring. After the walls and valves in the vein have been damaged, there is no way to repair them.

The valves in your veins are needed to make sure blood is flowing upward, toward your heart. However, the valves are fragile and may be damaged easily. If the valves are damaged, blood may begin to flow the wrong way. This is referred to as reflux, and it causes pressure to start building up in your veins in the lower portion of your legs. This is what causes discomfort and swelling.

The vein walls may also be scarred and damaged after a DVT occurs. If you engage in some activities, such as walking, the blood moving through your veins goes up. If veins are scarred, they will not expand like normal veins, so if the flow of blood goes up and they are unable to expand, it can result in swelling and throbbing pain in the lower portion of your legs.

As time passes, and the issue continues, this can cause severe damage to the skin on your leg. It may become dry around your ankles, itchy, and discolored. If the condition continues without treatment, the skin will feel leathery, be hard, and turn brown. If you happen to get a smaller cut or abrasion in this area, it can become a bigger sore that never heals. This is officially called a venous ulcer.

If your condition is more severe, the vein may be so severely damaged that it is completely blocked. If this happens, no blood can move through it at all. This is considered the most severe type of PTS.

Signs and Symptoms

Sometimes, cases of post-thrombotic syndrome only cause a few minor symptoms. However, in other situations, it may cause serious symptoms. Usually, the symptoms appear in the same leg affected by DVT. Some of the most common include:

  • Redness or darkening of affected skin on the leg
  • The feeling of heaviness in the leg
  • Leg swelling
  • Cramping, tingling, or itching in the leg
  • Widening of the veins in the leg
  • Leg pain that becomes worse when standing and better when raising or resting the leg
  • Sores or Leg Ulcers

If you see the above symptoms, especially if you have recently dealt with a DVT, you need to make an appointment with your doctor. They can diagnose the PTS based on your symptoms.

Post-thrombotic syndrome


Post-thrombotic syndrome can be diagnosed clinically, meaning there is no testing needed if the signs, symptoms, and history are consistent with the condition, however your healthcare provider may recommend blood work and/or an ultrasound of your legs out of thoroughness. When it comes to making a post thrombotic syndrome diagnosis, your doctor will ask you about your medical history. This includes if you have had a DVT. They will also ask you about your symptoms and conduct a physical exam. During your exam, your doctor will look at your medical history and legs carefully.

Additional tests may also be needed. The two most commonly used for diagnosing PTS include:

  • Blood tests to check for clotting issues
  • Ultrasound to find problems in the leg veins

In some situations, your doctor may use a Villalta score to assess your PTS. The scale will rate the severity of the signs and symptoms you have. If you have a score of 15 or higher, it means you are dealing with a severe case of PTS.


Post thrombotic syndrome treatment is based on the severity of your condition. Usually, treatment will include elevating the affected leg, the use of compression stockings or therapy, and exercise. Doctors may also prescribe you blood thinners to help prevent any more clots from showing up in the veins, along with pain medication.

Exercise and Elevation

Ideally, legs should be elevated above the level of the heart. You can obtain special leg elevation pillows that allow for comfortable reclining. It is not necessary to sleep with your legs elevated, nor is it recommended to spend all of your time resting, but when you are relaxing at home, try to elevate until your swelling improves. 

You should elevate your leg while you are sleeping or resting. By doing this, you are helping the blood in your veins return to the heart, thanks to gravity. Some exercises that may be used include flexing the ankle joint and engaging in activities that help strengthen the calves.

Compression Stockings

Properly fitting, graduated compression garments are an important part of the treatment of post-thrombotic syndrome. Your doctor or physical therapist can usually help recommend a particular type of garment which can be obtained from a medical supply store or over the counter. The right compression should be relatively comfortable to wear and practical to get on and off. There are many assistive devices that help with doffing and donning. 

Compression stockings are used to treat PTS. It is crucial that they fit correctly and provide the proper amount of compression. They are designed using unique elastic fabric and apply pressure on the ankle, improving blood flow while reducing swelling and pain. Usually, your doctor will help you select the right stockings for your needs.


Occasionally, long-term blood thinners are needed to prevent recurrent blood clots of the legs but there are otherwise no standard medications for the treatment of post-thrombotic syndrome. Recent studies, however, have shown improvement in symptoms like leg swelling and itching with the use of a supplement called horse chestnut extract


In some cases, there are procedures that can be used to help alleviate the symptoms of post-thrombotic syndrome. Some of the options include the following:

Thrombectomy or thrombolysis - hese procedures can be used to dissolve or remove clot from the vein. It is most effective while the clot is still in an acute, or early, phase, and often reserved for large clots.

Venous ablations or sclerotherapy - These procedures are used to close malfunctioning or damaged veins so that blood flow is redirected through healthier veins

Venoplasty and venous stenting - These procedures are used to widen veins that have become narrow due to scarring from a clot or external compression

For further guidance on treatment options read the NIH study, Guidance for the prevention and treatment of the post-thrombotic syndrome.


The symptoms of post-thrombotic syndrome can persist for months to years. For some people, symptoms remain mild and stable. For others, the condition can progress to the point of disablement. Fortunately, with good treatment, most patients are able to compensate for their symptoms and live healthy, active lives. The key to success appears to be early treatment and compliance with recommendations. 


It is possible to reduce the risk of PTS by lowering your risk of DVT. If you do not move or walk for long periods, the likelihood that you will develop DVT goes up. If you are immobile because of surgery or a medical condition, your doctor can provide additional tips to help you prevent this condition.

Some of these include:

  • Walking and moving as soon as you can
  • Using compression devices
  • Using prescription-grade compression stockings
  • Using blood-thinners

Treating cases of DVT is the best way to prevent PTS. Be sure to take your blood thinner if prescribed. Never miss a follow-up test with your doctor to check your blood levels while taking this medicine. It is also necessary to use your compression stockings or other devices as recommended.

Disease Progression

Post thrombotic syndrome typically occurs after someone has dealt with DVT. Usually, the condition occurs if the individual is not engaging in the proper treatment for DVT, such as taking blood thinners or wearing compression stockings. However, it can occur in other situations, too.

When PTS begins, the legs may be slightly uncomfortable, red, and a little itchy. However, as time passes, and the condition continues, the itchiness, pain, and discoloration on the lower portion of the legs will worsen. Inside the veins, the walls and valves are being seriously damaged, and it is important to note, the scarring and damage that occur are irreparable.

Over time, if no treatment is sought, the condition could result in immobility and other consequences.

This article is a comprehensive overview of Post Thrombotic Syndrome. However, it should not take the place of speaking with a physician. If you are experiencing any of the symptoms listed above, or know someone who is, contact us today to schedule a consultation.

You can also view other vascular diseases below:

Pelvic Congestion Syndrome

Deep Vein Thrombosis

Peripheral Arterial Disease (PAD)

May-Thurner Syndrome

Chronic Venous Insufficiency


Patients with PTS may see their condition improve with proper treatment; however, the symptoms may never go away completely. Most doctors will recommend being active daily and engaging in flexing movements to strengthen the calf muscles.

PTS may cause leg sores or ulcers. If this happens, professional wound care is necessary. Pentoxifylline and aspirin may help with the healing of ulcers. If the ulcer is infected, antibiotics may be required. More severe ulcers that do not improve with wound care therapy and medicines may require surgery to remove the tissue that is damaged.

There are several situations where you need to contact your doctor right away. These include:

  • A warm, painful area or ulcer on the leg
  • Signs of an infected ulcer on your leg
  • DVT symptoms like warmth, pain, or swelling, and heavy legs. 
Dr. Sanjiv Lakhanpal

Dr. Sanjiv Lakhanpal

Dr. Sanjiv Lakhanpal published in several medical research journals through the Lakhanpal Vein Foundation to help educate and raise awareness for vascular disease. He has been practicing medicine for 25 years, and is the founder of The Center for Vascular Medicine.