Approximately 40% of those who develop deep vein thrombosis (DVT) in the legs will develop a condition called post-thrombotic syndrome (PTS). The symptoms include chronic swelling, pain, tenderness, and, often, brown discoloration of the skin at the ankle or lower calf. Severe cases of PTS cause open, poorly-healing wounds near the ankles, often called venous stasis ulcers. These changes occur due to sustained high pressure in the veins of the legs causing stretching of the veins and migration of fluid, blood cells, and protein through the vein walls into the surrounding tissues.

Deep vein thrombosis often leaves many of the veins of the leg permanently obstructed or partially obstructed. This obstruction of the blood flow results in higher pressures in the veins below the obstructions. Additionally, DVT often injures the one-way valves in the veins causing extensive venous reflux in the deep veins (veins inside the muscles). The resulting downward flow of venous blood whenever the patient is sitting or standing greatly raises the pressures inside the veins and migration of blood components through the vein walls into the tissues causes damage to the surrounding tissues.

Post-thrombotic syndrome and venous stasis ulceration often may be prevented and other cases may be treated to improve the symptoms. Early diagnosis and prompt treatment of DVT may prevent PTS! Thrombolysis (see Treatments) in carefully selected patients for removal of extensive DVT in the veins of the thigh and/or pelvis may prevent PTS. Early treatment with anticoagulant drugs to prevent development of more thrombus is an important treatment as well.

The routine daily use of properly-fitted elastic compression hose as soon as a diagnosis of DVT is established is a very important part of treating DVT and continued use of support hose is important to prevent or limit the symptoms of PTS. Frequent walking after the diagnosis of DVT also reduces the likelihood of PTS.

It is now known that residual thrombus (clot) in the iliac veins of the pelvis which restricts venous outflow from the legs is the most important cause of PTS. Early diagnosis and treatment of residual thrombus or obstruction in the iliac veins is a very valuable technique to prevent or treat PTS in many patients. All patients who develop DVT in the thigh or who have PTS should undergo abdominal/pelvic venous color duplex ultrasound study to evaluate the iliac veins for thrombus or obstruction which often can be treated very effectively with iliac vein angioplasty and stenting. This abdominal/pelvic venous color duplex ultrasound exam generally is not available except in specialized centers. VeinCare Centers of Tennessee has been a leader in developing this technology and we speak at major national meeetings regarding our experience.