Atrial fibrillation (AF) is a major cause of stroke. To prevent this devastating complication, anticoagulants are recommended in some patients. Two classes of oral anticoagulants can be used for this indication: anti-vitamin K (AVK) agents, such as warfarin, and direct-acting non-vitamin K oral anticoagulants, also called new oral anticoagulants (NOACs). NOACs include agents with two distinct modes of action: direct factor Xa inhibitors (apixaban, rivaroxaban, edoxaban) on the one hand and direct thrombin inhibitors (dabigatran) on the other hand. These molecules have been compared individually to warfarin: While showing similar efficacy, they had a better safety profile in terms of bleeding, with a lower risk of hemorrhagic stroke and intracranial hemorrhage. They are therefore preferred over AVKs.
The choice of the anticoagulant is made on a case-by-case basis, always taking into account the risk of stroke (using anticoagulants in patients without thromboembolic risk factors is currently not recommended) and bleeding (dosage!). These two aspects should be assessed prior to any prescription. When choosing an anticoagulant agent, the physician should also consider the presence of coronary artery disease (concomitant use of antiplatelet therapy), the patient's age and weight (dose adjustment!), renal function (important for dabigatran), the patient’s preference (once daily vs twice daily administration), and the patient’s understanding of the treatment, which is decisive for therapeutic compliance. It should be noted that dabigatran is currently the only NOAC for which a specific reversal agent is available that can be used in some cases when emergency surgery is required or major bleeding has to be controlled.
Key Words
Oral anticoagulants, new oral anticoagulants, NOAC, atrial fibrillation, stroke, warfarin, reversal agent, hemorrhage
What is already known about the topic?
Atrial fibrillation (AF) is a major cause of stroke. To prevent this dramatic complication, it is recommended to prescribe anticoagulants. There are two classes of oral anticoagulants available for this indication: anti-vitamin K (AVK) agents and new oral anticoagulants (NOACs). NOACs have been compared individually to warfarin (but no direct comparison between NOACs is available), showing similar efficacy but with lower risks of hemorrhagic stroke and intracranial bleeding. They are therefore preferred over AVKs, but each has its own particularities. Thus, when deciding to prescribe a NOAC, the physician should be aware of these particularities in order to make the right therapeutic choice, which will finally ensure safety and efficacy to the patient.
What does this article bring up for us?
This article highlights the important role played by anticoagulants in the prevention of AF-related strokes. It recalls the principle of NOACs and their specificities and provides the reader with practical information to guide him/her in the choice of a drug based on the patient’s profile.