New-onset atrial fibrillation and warfarin initiation: High risk periods and implications for new antithrombotic drugs

David A. Garcia; Renato D. Lopes; Elaine M. Hylek

doi:10.1160/TH10-07-0491

Thrombosis and Haemostasis, Table of Contents

Thromb Haemost 2010; 104(06): 1099-1105
DOI: 10.1160/TH10-07-0491

Review Article

Schattauer GmbH

New-onset atrial fibrillation and warfarin initiation: High risk periods and implications for new antithrombotic drugs

David A. Garcia

¹Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA

,

Renato D. Lopes

²Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina, USA

,

Elaine M. Hylek

³Department of Medicine, Research Unit-Section of General Internal Medicine, Boston University School of Medicine, Boston, Massachusetts, USA

› Author Affiliations

Abstract

Summary

Atrial fibrillation is a common condition that increases the risk of stroke in many patients. Although warfarin has been shown to reduce the risk of stroke, many patients who might benefit from anticoagulation do not receive this therapy. Fear of bleeding is the most often cited reason. Several new anticoagulant medications are being studied to determine their efficacy and safety relative to warfarin. Unlike earlier trials that established the superiority of warfarin over placebo, recent trials in atrial fibrillation have enrolled a disproportionate number of patients already taking warfarin. This review suggests that the risk of both haemorrhage and stroke are highest when atrial fibrillation is newly diagnosed and during the initiation of anticoagulant medication. Randomised controlled trials designed to evaluate the safety and efficacy of new anti-thrombotic agents should include substantial numbers of patients without prior exposure to anticoagulation since these individuals are at the highest risk for bleeding and thromboembolism.

Keywords

Clinical trials - oral anticoagulants - thrombosis - stroke prevention - heart

Full Text

References

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