Postthrombotic syndrome

Definition

Postthrombotic syndrome (PTS) is the most common late complication after leg vein thrombosis (closure of a vein by a blood clot). It leads to chronic reflux congestion, so that the blood cannot flow back to the heart properly. The blood therefore bypasses the partially occluded veins by switching to continuous veins (so-called bypass circulation), and this can result in so-called chronic venous insufficiency.

On the other hand, as a result of the thrombosis, weakness and malfunctioning of the venous valves often remain or often worsen. This means that the valves are not able to prevent the blood from flowing back into the legs, resulting in increased blood loss to the legs. This can lead to house changes and open spots.

Causes of the postthrombotic syndrome

Postthrombotic syndrome affects patients with deep leg vein thrombosis or multilevel thrombosis. In 50% and more cases, the postthrombotic syndrome is the result of a multi-stage thrombosis. This means that several blood clots are present at different sites in the leg.

For example, they may be in the calf, knee or thigh and may extend partially into the pelvis. The risk factors for developing thrombosis and thus suffering from a postthrombotic syndrome include all previous diseases in the venous system, such as phlebitis or varicose veins (varices), as well as congenital thrombosis tendencies. Risk factors also include: The trigger for thrombosis is often prolonged immobilization, for example on long flights, in hospital or after bone fractures. In hospital, attempts are made to minimize the risk of thrombosis by wearing compression stockings and taking medication to prevent thrombosis.

  • Overweight
  • Smoking
  • Oestrogen-containing medications, such as the pill
  • Pregnancy
  • Cancer diseases
  • Operations and traumas

Staging of the postthrombotic syndrome

To assess the severity of a postthrombotic syndrome, the disease was divided into four stages. Tissue hardening or changes and their depth as well as swellings are taken into account.

  • The first stage is accompanied by swelling, but there is no tissue hardening or alteration.
  • In stage II, in addition to swelling, hardening of the skin and subcutaneous fatty tissue occurs.
  • Stage III is characterized by a tissue alteration that extends beyond the subcutaneous fatty tissue.
  • The fourth stage is accompanied by a hardening that is extensive (for example, affecting the entire lower leg) and deep. In most cases, open ulcers (ulcers) also occur in the fourth stage.