Post-thrombotic syndrome (PTS) is the development of chronic venous symptoms and/or signs secondary to deep venous thrombosis. This replaces the prior terminology "postphlebitic syndrome" . Injury to the venous valvular system produces symptoms of chronic venous insufficiency that can include pain, venous dilation, edema, pigmentation, skin changes, and venous ulcers. Development of post-thrombotic syndrome was the major factor impairing quality of life in a study of patients two years after deep venous thrombosis (DVT) .
This topic reviews the epidemiology and prevention of post-thrombotic syndrome. The management of patients with chronic venous insufficiency as a result of post-thrombotic syndrome is discussed separately. (See "Medical management of lower extremity chronic venous disease".)
Post-thrombotic syndrome affects 23 to 60 percent of patients following an episode of deep vein thrombosis (DVT) . In a large prospective study of patients with an initial venographically-confirmed episode of deep venous thrombosis, the cumulative incidence of post-thrombotic syndrome at one, two, and five years was 17, 23, and 28 percent, respectively; these percentages did not increase thereafter . The incidence of severe skin changes indicative of chronic venous insufficiency, including venous ulcer, increased from 2.6 percent at one year to 9.3 percent at five years.
Most data regarding the natural history of chronic venous insufficiency are from prospective or cross-sectional studies of patients with acute deep venous thrombosis. There are conflicting reports regarding the risk of developing the post-thrombotic syndrome, but it is felt to be associated with several underlying factors which are presented below .
Patient characteristics — Higher body mass index appears to be a risk factor for development of the post-thrombotic syndrome after DVT [6,7]. There does not appear to be a consistent relationship between age or sex and the development of post-thrombotic syndrome [5,6,8-12].