Context

Since its isolation during the early half of the 20th century from the mouldy hay responsible for ‘sweet clover disease’ in cattle, warfarin has become the most widely used oral anticoagulant.1 Indications include atrial fibrillation (AF), mechanical prosthetic valves and venous thromboembolism treatment.2 Warfarin reduces stroke risk in patients with AF by nearly two-thirds; AF accounts for 20% of ischaemic strokes, which tend to be more severe than those due to other aetiologies. In the late 1990s, reports began to emerge concluding that patients with AF …