The Lupus Research Unit, the Rayne Institute, St, Thomas' Hospital, London, SE1 7EH, UK. ana.fonseca@fcm.unl.pt.
ABSTRACT: Patients with antiphospholipid syndrome are at increased risk for recurrent arterial and venous thrombosis and therefore benefit from long term warfarin therapy. The optimal duration of warfarin therapy after a first venous thromboembolic event is however a matter of some controversy and many questions remain unanswered. After reviewing and analysing the available evidence, we discuss some common scenarios in everyday clinical practice where treatment decisions are difficult.