Post-thrombotic syndrome (PTS) is a long-term condition that occurs as a result of a deep vein thrombosis (DVT). The veins in our arms and legs have small valves inside that ensure the blood flows correctly back toward the heart. A DVT is a blockage or clot that obstructs the vein and can lead to the valves becoming damaged.

More than one third of people who have DVT then develop PTS, the symptoms of which include redness, swelling, ulcers, and chronic leg pain. PTS can affect your mobility and is expensive to treat, so it’s best to take preventative measures. It is most common for a DVT to occur in the legs.

The primary cause of PTS is when the valves and walls of the veins become damaged as a result of a DVT. Prompt diagnosis and treatment of a DVT is necessary to prevent this damage from occurring, as once the valves and walls of the vein are damaged, they cannot be repaired.

Vein valves are necessary to ensure that the blood flows in an upward direction toward the heart. They are incredibly fragile and can become damaged easily. When valves are damaged, blood can flow the wrong way. This is called reflux. It causes pressure to build up in the veins in the lower part of our legs, which leads to swelling and discomfort.

The walls of the vein can also become damaged and scarred after a DVT. When we do certain physical activities, like walking, the flow of blood through our veins increases. Scarred veins do not expand as normal veins do, so when the flow of blood increases and they cannot expand, it causes a throbbing pain and swelling in the lower part of our legs.

Eventually, this can cause damage to the skin on the leg. It becomes dry around the ankles, discoloured, and itchy. It later becomes brown in colour, hard, and leathery to touch. A minor abrasion can then become a larger sore that doesn’t heal. This is called a venous ulcer.

In incredibly severe cases, the vein can be so badly damaged that it becomes completely blocked off. No blood is able to flow through it at all. This is the most serious type of PTS.

The most usual symptoms of PTS are:

  • aching, swelling, and pain in the leg, which is usually worse can after standing for long periods or walking and is typically relieved by resting or raising the leg
  • heaviness of the legs
  • itchy legs
  • tingling legs
  • cramps in the legs
  • ulcers or sores on the legs

If you develop any of these symptoms, particularly if you know you’ve had a recent DVT, you should see your doctor as soon as possible. Your doctor can diagnose PTS on the basis of these symptoms. There are no diagnostic tests.

Treatment options differ depending on how severe the condition is. Treatment usually includes elevation of the affected limb, exercise, and compression therapy or stockings. Doctors can also prescribe blood-thinners, to prevent any further clots forming in the veins, and pain medication.

Elevation and exercise

Elevate the affected limb while you’re resting or sleeping. This helps blood return to the heart using gravity. Exercises that involve flexing the ankle and strengthening the calves can also be helpful.

Compression stockings

These are commonly used in the treatment of PTS. It’s important that they fit well and provide the right amount of compression. They are made of special elastic fabric, and they apply pressure to the ankle, which improves blood flow and reduces pain and swelling. Your doctor will help you choose the most appropriate stocking type and degree of pressure for your condition.

The complications of PTS are often developed when the condition isn’t promptly treated and effectively managed. When leg ulcers develop, they are incredibly difficult to heal and can become infected. This threatens your mobility and in rare cases can lead to sepsis.

PTS is a long-term condition that is difficult to treat and manage. It usually causes discomfort and can lead to greater complications. In light of the fact that there is no cure for the condition, it is best to take measures to prevent it from ever occurring. The key to this is prompt diagnosis and treatment of a DVT. The quicker the clot is dissolved the less damage it will do to the valves and walls of the veins. Compression stockings can be worn preventatively in high risk situations for DVT such as during a hospital stay or on long-haul flights.