title: Antithrombotic therapy in atrial fibrillation: aspirin is rarely the right choice.
abstract: Atrial fibrillation, the commonest cardiac arrhythmia, predisposes to thrombus formation and consequently increases risk of ischaemic stroke. Recent years have seen approval of a number of novel oral anticoagulants. Nevertheless, warfarin and aspirin remain the mainstays of therapy. It is widely appreciated that both these agents increase the likelihood of bleeding: there is a popular conception that this risk is greater with warfarin. In fact, well-managed warfarin therapy (INR 2-3) has little effect on bleeding risk and is twice as effective as aspirin at preventing stroke. Patients with atrial fibrillation and a further risk factor for stroke (CHA2DS2-VASc >0) should therefore either receive warfarin or a novel oral agent. The remainder who are at the very lowest risk of stroke are better not prescribed antithrombotic therapy. For stroke prevention in atrial fibrillation; aspirin is rarely the right choice.
authors: Physiological Laboratory, University of Cambridge, Downing Street, Cambridge CB2 3EG, UK. ins20@cam.ac.uk
authors: Ian N
authors: IN
authors: Sabir
authors: Gareth D K
authors: GD
authors: Matthews
authors: Christopher L-H
authors: CL
authors: Huang
mesh_terms: D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects*; D001241:Aspirin / Q000008:administration & dosage / Q000009:adverse effects*; D001281:Atrial Fibrillation / Q000188:drug therapy* / Q000503:physiopathology; D004334:Drug Administration Schedule; D004347:Drug Interactions; D005260:Female; D006801:Humans; D008297:Male; D015201:Meta-Analysis as Topic; D018579:Patient Selection; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000009:adverse effects*; D017410:Practice Guidelines as Topic; D018570:Risk Assessment; D012307:Risk Factors; D055502:Secondary Prevention; D020521:Stroke / Q000188:drug therapy* / Q000503:physiopathology / Q000517:prevention & control; D014859:Warfarin / Q000008:administration & dosage / Q000009:adverse effects*
chemical_list: D000925:Anticoagulants; D010975:Platelet Aggregation Inhibitors; D014859:Warfarin; D001241:Aspirin
keywords: Anticoagulant; Antithrombotic; Aspirin; Atrial Fibrillation; Warfarin
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