Antithrombotic Therapy for Patients with Atrial Fibrillation


Project Line:
Health Technology Review
Project Number:

CADTH previously reviewed the optimal management of warfarin and the use of new oral anticoagulants for patients with atrial fibrillation. The Antithrombotic Therapy for Patients With Atrial Fibrillation project was an extension of the previous review of new oral anticoagulants, and it assessed all antithrombotic drugs currently used to prevent stroke in patients with atrial fibrillation:

  • antiplatelet drugs such as acetylsalicylic acid (ASA) and clopidogrel
  • anticoagulant drugs such as warfarin, dabigatran, rivaroxaban, and apixaban.


The Canadian Agency for Drugs and Technologies in Health (CADTH) developed the following tools to help transition our recommendations from paper into practice. To make these tools relevant to different audiences, CADTH can tailor specific tools to individual needs and settings. Contact us if you would like our assistance in tailoring any of these tools to meet your unique needs as a health care provider, policy-maker, or consumer.

Key Messages

CADTH's work on this project resulted in several key messages:

  • Warfarin is the recommended first-line therapy for preventing stroke in patients with atrial fibrillation.
    • Warfarin is proven to be a safe, effective, and cost-effective first choice for therapy.
    • Many patients taking warfarin do well on the medication. For these patients, there is no evidence to support switching therapies.
  • New oral anticoagulants are a second-line option for some patients with non-valvular atrial fibrillation who are not doing well on warfarin.
    • Although they are as effective at preventing stroke as warfarin, the newer drugs are more expensive and little is known about their long-term safety.
  • If a new oral anticoagulant is prescribed, patients must be monitored.
    • Regular assessments of adherence to treatment, kidney function, drug interactions, and bleeding risk are necessary.
    • If bleeding occurs, there is no antidote or proven management strategy.
  • For people who are able to use an anticoagulant, anticoagulant drugs should be used in preference to antiplatelet drugs.

The Canadian Drug Expert Committee (CDEC) provided expert guidance on this project.

Stakeholder feedback was considered at specific stages of this project.

By reviewing the evidence and developing reports and tools, CADTH provides health professionals, policy-makers, and patients with the evidence-based resources they need to make informed decisions.