Summary. Up to half of patients with proximal deep vein thrombosis (DVT) will develop post-thrombotic syndrome (PTS) despite optimal anticoagulant therapy. PTS significantly impacts upon quality of life and has major healtheconomic implications. This narrative review describes the pathophysiology, risk factors, and diagnosis, prevention and treatment of PTS, to improve our understanding of the disease and guide treatment. Relevant articles were identified through systematic searches of the PubMed, EMBASE and Cochrane databases between 1966 and November 2011. Studies were included for detailed assessment if they met the following criteria: published in English, human study participants, study population aged > 18 years, and lower limb post-thrombotic syndrome. All non-systematic reviews and single patient case reports were excluded. Recurrent thrombosis, thrombus location and obesity are major risk factors, whereas the importance of gender and age remain uncertain. The diagnosis of PTS is based on clinical findings in patients with a known history of DVT. Several clinical scales have been described, with the Villalta Score gaining increasing popularity. Adequate anticoagulation and use of elastic compression stockings (ECS) following DVT can reduce the incidence of PTS. Catheter-directed thrombolysis and mechanical thrombectomy of acute DVT may preserve valvular function. Studies to date of these techniques are encouraging, and have reported improved hemodynamics and a reduced incidence of PTS. The management of established PTS is challenging. Compression therapy, aimed at reducing the underling venous hypertension, remains the mainstay of treatment. This is despite a paucity of highquality evidence to support its use. Pharmacologic and surgical treatments have also been described, with a number of studies citing symptomatic improvement.

The Villalta score, combined with a venous disease-specific quality-of-life questionnaire, should be considered the "gold standard" for the diagnosis and classification of post-thrombotic syndrome.

This review emphasizes the requirement for more attention to be placed on the treatment of calf muscle pump failure in cases of CVD by use of exercise treatment programs or other methods, which may be of clinical importance in managing symptomatic disease. To establish this in routine clinical practice, these results would need to be replicated in appropriate clinical trials. It would also be logical to look at other modifiable muscle pumps, such as the thigh and foot, and to explore the potential benefit of electrical devices acting on the leg (eg, electrical muscular or neuromuscular stimulation), especially for those patients in whom exercise capacity is limited.

Published data reporting the safety and efficacy of IVC filter use in bariatric surgical patients is highly heterogeneous. There is no evidence to suggest that the potential benefits of IVC filters outweigh the significant risks of therapy.

There is a marked disparity across Europe between the predicted number of patients with varicose veins requiring treatment and the actual care given. The factors influencing this need more detailed investigation.