Emerging therapies for stroke prevention in atrial fibrillation
1Department of Medicine, McMaster University, Hamilton, Ontario, Canada
2Henderson Research Centre, 711 Concession Street, Hamilton, Ontario L8V 1C3, Canada
3Division of Internal and Cardiovascular Medicine, Department of Internal Medicine, University of Perugia, Perugia, Italy
4Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
* Corresponding author. Tel: +1 905 574 8550; fax: +1 905 575 2646. E-mail address: jweitz{at}thrombosis.hhscr.org
Atrial fibrillation (AF) is a major risk factor for stroke. Recent studies show that treatment strategies which combine control of ventricular rate with antithrombotic therapy are as effective as those strategies aimed at restoring sinus rhythm. Current antithrombotic therapy regimens in patients with AF involve chronic anticoagulation with dose-adjusted vitamin K antagonists (VKAs), unless patients have a contraindication to these agents or are at low risk for stroke. AF patients at low risk for stroke may benefit from aspirin. Although VKAs are effective, their use is problematic, highlighting the need for new antithrombotic strategies. This paper will (i) provide an overview of the clinical trials that form the basis for current antithrombotic guidelines in patients with AF, (ii) highlight the limitations of current antithrombotic drugs used for stroke prevention, (iii) review the pharmacology of new antithrombotic drugs under evaluation in AF, (iv) describe ongoing trials with new antiplatelet therapies and idraparinux, and completed studies with ximelagatran in patients with AF, (v) discuss the role of non-pharmacological techniques to reduce the risk of stroke in AF patients, and (vi) provide clinical perspective into the potential role of new antithrombotic drugs in AF.
Key Words: Anticoagulants • Antiplatelets • Atrial fibrillation • Surgery • Vitamin K antagonists • Ximelagatran