Implications of the CHA2DS2-VASc and HAS-BLED Scores for Thromboprophylaxis in Atrial Fibrillation

  • Gregory Y.H. Lip
    Requests for reprints should be addressed to Gregory Y. H. Lip, MD, University of Birmingham Centre for Cardiovascular Sciences, City Hospital, Birmingham B18 7QH, England, UK
    University of Birmingham Centre for Cardiovascular Sciences, City Hospital, Birmingham, England, UK
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Published:September 30, 2010DOI:


      There is increasing recognition of the value of oral anticoagulation for stroke prevention in atrial fibrillation, as well as the availability of new oral anticoagulants that overcome the limitations of warfarin, implying that even more atrial fibrillation patients will be using oral anticoagulation, with the role of aspirin being less defined. Thus, we need a paradigm shift so that stroke risk assessment can be simplified in the identification of those patients who are truly at low risk (ie, CHA2DS2-VASc [Congestive heart failure, Hypertension, Age ≥75 years, Diabetes mellitus, Stroke, Vascular disease, Age 65-74 years, Sex category] score=0) who could be treated with no antithrombotic therapy, and all others (ie, CHA2DS2-VASc score ≥1), would be considered for oral anticoagulation. A simple bleeding risk assessment can clearly help guide office management here. The new HAS-BLED (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile International Normalized Ratio, Elderly, Drugs/alcohol concomitantly) bleeding risk schema has been proposed as a simple, easy calculation to assess bleeding risk in atrial fibrillation patients, whereby a score of ≥3 indicates “high risk” and some caution and regular review of the patient is needed, following the initiation of antithrombotic therapy, whether with oral anticoagulation or antiplatelet therapy.


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