Secondary stroke prevention in patients with atrial fibrillation
Patients with atrial fibrillation who have had a transient ischaemic attack have a high risk of ischaemic stroke and patients with ischaemic stroke have a high risk of a recurrent stroke. The highest risk of a recurrent stroke is in the first 2 weeks after the initial cerebrovascular event. In secondary stroke prevention, acetylsalicylic acid has only a marginal effect with a relative risk reduction of 18% compared to placebo. The combination of acetylsalicylic acid plus clopidogrel is superior to acetylsalicylic acid monotherapy but inferior to anticoagulation with warfarin. The non-vitamin K antagonist oral anticoagulants apixaban, dabigatran, edoxaban, and rivaroxaban as a group are superior to warfarin in prevention of recurrent stroke with a relative risk reduction of 14%, and reduce the risk of intracerebral haemorrhage by 50% and of major bleeding by 11% compared to vitamin K antagonists.