Postthrombotic syndrome

Persistent symptoms, and signs of chronic venous insufficiency‘s, or both, occuring three-six months from the initial diagnosis of DVT, occurs in 30% of patients treated with anticoagulation for DVT.

Post thrombotic syndrome causes disability, decreased function,substantial health costs, venous ulcerations of the skin of the lower extremity, typically around the medial malleolus.

Associated and their quality of life and substantial financial burden.

About half of patients with symptomatic DVT develop some degree of PTS.

Daily use of elastic compression stockings reduces the risk of PTS by about 50%.

Results from venous obstruction, and venous incompetence caused by inflammation of the venous valves in response to acute thrombotic occlusion, or both.

Its pathophysiology involves persistent venous  outflow obstruction, venous valvular damage and incompetence, venous hypertension, and inflammation of the wall of the vein.

The combination of inflammation and venous hypertension leads to capillary leak, chronic leg discomfort, edema, hyperpigmentation, and often ulceration.

The process may mimic cellulitis.

The presence of chronic venous insufficiency, with venous varicosities and hyperpigmentation support the diagnosis.

Diagnosis is based on persistent symptoms or signs of chronic venous insufficiency the three-six months after DVT in the absence of recurrent thrombosis.

Catheter based therapy, compression stockings, or extended duration of anticoagulantion  reduce the risk of postthrombotic syndrome.

Accelerated removal of thrombus material by thrombolysis can prevent pain dysfunction and PTS.

Catheter directly thrombolysis improves the clinically relevant long-term outcome after iliofemoral

DVT by reducing PTS compared with conventional treatment with anti coagulation and an elastic compression stockings alone: absolute reduction in about 14%(CaVent study).

Usually manifests within 1-2 years after DVT (78%).

Incidence after DVT approximately 10-50%.

Approximately 20-50% of patients with proximal DVT develop this syndrome.

Pain swelling,heaviness, edema, skin pigmentation, and in very severe cases the development of an ulcerations characterize this syndrome.

The clinical presentation is diverse and ranges from lower extremity edema to chronic debilitating pain, intractable edema, and venous ulcers, occurring in approximately 5% of patients.

It is suggested obstruction of venous outflow due to impaired thrombus resolution and a thrombus induced inflammatory response with damage of venous valves and vein wall fibrosis causing reflux and venous hypertension.

Post thrombotic syndrome (PTS) markedly impairs quality of life, and parallels the difficulties as those with severe COPD, CHF, or angina pectoris.

Sub therapeutic anticoagulation with warfarin has been associated with a 2-3 fold increased risk of post phlebotic syndrome or a dose response relationship with time in the sub therapeutic range.

Risk factors include iliofemoral DVT, recurrent ipsilateral DVT, persistent symptoms after one month of therapeutic and a coagulation, increased BMI, advanced age, and suboptimal anticoagulation.

Early thrombus removal by catheter directed thrombolysis (CDT) can lead to reduction in the incidence of PTS and improve quality of life, however, a study comparing outcomes of catheter directed thrombolysis with anticoagulation versus anti-coagulation alone did not find any significant difference in mortality rates, but evidence of higher adverse events in the CDT group (Bashir R et al).

Use of graded elastic compression stockings for at least 2 years after proximal DVT cuts the rate of postthrombotic syndrome in half.