Evaluation of oral anticoagulation therapy: rationale and design of the thrombEVAL study programme

Background: Since decades, oral anticoagulation (OAC) with vitamin K antagonists (VKA) is an established therapy for both prevention and treatment of thromboembolism in daily clinical routine. Increasing life expectancy, demographic changes, and novel oral anticoagulants have led to an increasing complexity of medical therapy. However, data on quality and management of VKA therapy with phenprocoumon in current medical care are limited. Our aim is to investigate the quality of OAC with VKA in current health care and to evaluate the potential for improvements.

Study design: The investigator-initiated thrombEVAL study programme comprises two cohorts of patients treated with vitamin K antagonists for oral anticoagulation therapy in real-life settings: a multicentre cohort of patients in regular medical care and a multilocal, single-centre cohort of patients in a telemedicine-based coagulation service. The study programme is expected to enrol a total number of approximately 2000 to 2500 patients. Both cohorts will build on a detailed clinical assessment of participants and anticoagulation therapy at study enrolment. Subsequently active and passive follow-up investigations are carried out to document and validate complications of the treatment. The primary short-term outcome is the distribution of time in therapeutic range; the primary long-term outcome comprises the composite of stroke, systemic embolism, myocardial infarction, major and clinically relevant bleeding, and death.

Conclusions: The thrombEVAL project will provide a large prospective observational cohort of patients predominantly treated with phenprocoumon. It will evaluate the quality of oral anticoagulation in regular medical care and a telemedicine-based coagulation service.