Table of Contents
Volume 2012 (2012), Article ID 108983, 10 pages
Review Article

Stroke Prevention in Atrial Fibrillation: Understanding the New Oral Anticoagulants Dabigatran, Rivaroxaban, and Apixaban

1Department of Cardiology, National Heart Centre Singapore, 17 Third Hospital Avenue, Singapore 168752
2Duke-NUS Graduate Medical School, 8 College Road, Singapore 169857
3Department of Cardiology, National University Heart Centre, 5 Lower Kent Ridge Road, Singapore 119074
4Mount Elizabeth Medical Centre, 3 Mount Elizabeth No. 14-10, Singapore 228510
5Mount Elizabeth Medical Centre, 3 Mount Elizabeth No. 14-01, Singapore 228510
6Gleneagles Medical Centre, 6 Napier Road No. 03-04, 25499, Singapore
7Department of Neurology, National Neuroscience Institute, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433

Received 29 June 2012; Accepted 1 August 2012

Academic Editor: Walter Ageno

Copyright © 2012 Tan Ru San et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Unlike vitamin K antagonists (VKAs), the new oral anticoagulants (NOACs)—direct thrombin inhibitor, dabigatran, and direct activated factor X inhibitors, rivaroxaban, and apixaban—do not require routine INR monitoring. Compared to VKAs, they possess relatively rapid onset of action and short halflives, but vary in relative degrees of renal excretion as well as interaction with p-glycoprotein membrane transporters and liver cytochrome P450 metabolic enzymes. Recent completed phase III trials comparing NOACs with VKAs for stroke prevention in atrial fibrillation (AF)—the RE-LY, ROCKET AF, and ARISTOTLE trials—demonstrated at least noninferior efficacy, largely driven by significant reductions in haemorrhagic stroke. Major and nonmajor clinically relevant bleeding rates were acceptable compared to VKAs. Of note, the NOACs caused significantly less intracranial haemorrhagic events compared to VKAs, the mechanisms of which are not completely clear. With convenient fixed-dose administration, the NOACs facilitate anticoagulant management in AF in the community, which has hitherto been grossly underutilised. Guidelines should evolve towards simplicity in anticipation of greater use of NOACs among primary care physicians. At the same time, the need for caution with their use in patients with severely impaired renal function should be emphasised.