Trial Protocol: A randomised controlled trial of extended anticoagulation treatment versus routine anticoagulation treatment for the prevention of recurrent VTE and post thrombotic syndrome in patients being treated for a first episode of unprovoked VTE (The ExACT Study)

BMC Cardiovascular Disorders

David Fitzmaurice²  FD Richard Hobbs¹  Peter Rose⁴  Will Lester³  Roger Holder²  Linda Nichols²  Ellen Murray²  Jayne Tullett² 

[1] Department of Primary Care Health Sciences, University of Oxford, New Radcliffe House, Walton Street, Oxford, OX2 6NW, UK;Primary Care Clinical Sciences, School of Health and Population Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK;Haemophilia Unit, Queen Elizabeth Hospital, Birmingham, B15 2TH, UK;Warwick Hospital, Lakin Road, Warwick, CV34 5BW, UK

关键词: D-dimer;    Post thrombotic syndrome;    Extended warfarin;    Pulmonary embolism;    Deep vein thrombosis;    Venous thromboembolism;   

Others  :  857821
DOI  :  10.1186/1471-2261-13-16

 received in 2013-01-03, accepted in 2013-02-01,  发布年份 2013

【 摘 要 】

Background

Venous thromboembolism comprising pulmonary embolism and deep vein thrombosis is a common condition with an incidence of approximately 1 per 1,000 per annum causing both mortality and serious morbidity. The principal aim of treatment of a venous thromboembolism with heparin and warfarin is to prevent extension or recurrence of clot. However, the recurrence rate following a deep vein thrombosis remains approximately 10% per annum following treatment cessation irrespective of the duration of anticoagulation therapy. Patients with raised D-dimer levels after discontinuing oral anticoagulation treatment have also been shown to be at high risk of recurrence.

Post thrombotic syndrome is a complication of a deep vein thrombosis which can lead to chronic venous insufficiency and ulceration. It has a cumulative incidence after 2 years of around 25% and it has been suggested that extended oral anticoagulation should be investigated as a possible preventative measure.

Methods/design

Patients with a first idiopathic venous thromboembolism will be recruited through anticoagulation clinics and randomly allocated to either continuing or discontinuing warfarin treatment for a further 2 years and followed up on a six monthly basis. At each visit D-dimer levels will be measured using a Roche Cobas h 232 POC device. In addition a venous sample will be taken for laboratory D-dimer analysis at the end of the study. Patients will be examined for signs and symptoms of PTS using the Villalta scale and complete VEINES and EQ5D quality of life questionnaires.

Discussion

The primary aim of the study is to investigate whether extending oral anticoagulation treatment (prior to discontinuing treatment) beyond 3–6 months for patients with a first unprovoked proximal deep vein thrombosis or pulmonary embolism prevents recurrence. The study will also determine the role of extending anticoagulation for patients with elevated D-dimer levels prior to discontinuing treatment and identify the potential of D-dimer point of care testing for identification of high risk patients within a primary care setting.

Trial registration

ISRCTN73819751

【 授权许可】

   
2013 Tullett et al.; licensee BioMed Central Ltd.

【 图 表 】

【 参考文献 】

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