ISBN:  Unavailable

Category: Unavailable

Page count: Unavailable

[Truncated abstarct] Deep vein thrombosis is a major health problem that carries the immediate and potentially fatal risk of pulmonary embolism. The post-thrombotic syndrome (PTS) is a long-term complication of deep vein thrombosis (DVT) and affects 20%-82% of patients. One quarter to one third of these suffer the severe forms of PTS which are lipodermatosclerosis and venous leg ulceration. Venous leg ulcers are a difficult clinical problem because they are slow to heal, and have a high recurrence rate that is reported in both Europe and Australia to be as high as 76%. Chronic venous disease is a major burden on health care resources impacting on both community and in-patient care. The global costs for treatment have been estimated at between $750 million and $1 billion per year. The cost of the social implications and the impact on the quality of life have not been effectively measured. The venous changes that occur as the result of a DVT are variable, however the severity of these changes cannot be predicted by the extent of the original thrombus or the associated haemodynamic changes. It is not known why some patients develop lipodermatosclerosis and ulceration following a DVT and why others remain without symptoms. A significant number of patients who develop venous thrombosis have been found to have hypercoagulable states. Many of these have a genetic cause, especially in patients with recurring deep vein thrombosis, who may possess multiple genetic abnormalities. The extent to which individuals are affected by chronic venous disease after a DVT varies considerably, which suggests the interaction of multiple factors, which may be genetic, environmental and clinical. Little is understood about factors that predict the development of severe venous changes following DVT. Identifying patients at high risk of developing lipodermatosclerosis and venous leg ulceration would aid in directing existing and future treatments that might modify the management of patients with DVT and provide them with practical information on their expected outcome. The aim of this thesis was to determine factors that are associated with the development of lipodermatosclerosis and venous ulceration in patients with a previous deep vein thrombosis, and to thereby gain an insight into factors that might be prognostic for the outcomes of severe venous disease. Multiple factors were considered in this study including individual patient characteristics, genetic polymorphisms, venous function, tissue oxygenation, and skin oedema. The study consisted of two cohorts of patients who all had a proven deep vein thrombosis more than 2 years previously. One cohort (n=161) was identified from hospital radiology records. These patients were assessed for the presence of skin changes by attending an assessment visit (n=127 ) or by responding to a postal questionnaire if they were not willing to attend a visit. The second cohort (n=80) was identified through the leg ulcer clinic as patients with a venous leg ulcer who had a previous DVT in that ulcerated leg...