Related Experiment Video
Updated: Dec 7, 2025
The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Protocol, rationale and design of DAbigatran for Stroke PreVention In Atrial Fibrillation in MoDerate or Severe
Mi Zhou1, Esther W Chan2, Jo Jo Hai1
1Cardiology Division, Department of Medicine, University of Hong Kong, Hong Kong, Hong Kong SAR, China.
Insights
This study investigates dabigatran versus warfarin for stroke prevention in atrial fibrillation (AF) patients with moderate to severe mitral stenosis (MS). It aims to determine if NOACs are safe and effective in this specific patient group.
Area of Science:
- Cardiology
- Pharmacology
- Clinical Trials
Background:
- International guidelines recommend non-vitamin K oral anticoagulants (NOACs) for stroke prevention in non-valvular atrial fibrillation (AF) due to superior safety and comparable efficacy to warfarin.
- However, NOACs have not been evaluated in AF patients with moderate or severe mitral stenosis (MS), a condition more prevalent in Asian countries.
- Current recommendations for stroke prevention in this AF with MS population remain warfarin therapy.
Purpose of the Study:
- To evaluate the safety and efficacy of dabigatran for stroke prevention in patients with AF and moderate or severe MS.
- To compare dabigatran with warfarin in this specific high-risk patient population.
Main Methods:
- A prospective, randomized, open-label trial with blinded endpoint adjudication.
- Patients with AF and moderate/severe MS (not undergoing intervention within 12 months) randomized 1:1 to dabigatran (110mg or 150mg BID) or warfarin (INR 2-3).
- Exclusion criteria: creatinine clearance <30 mL/min or need for antiplatelet therapy.
- Primary outcome: composite of stroke and systemic embolism. Secondary outcomes include various bleeding and mortality events.
- Estimated sample size: 686 participants.
Main Results:
- This is a pre-results abstract; no main results are available at this time.
- The trial is registered (NCT04045093) and ongoing.
Conclusions:
- This trial is crucial for establishing evidence-based stroke prevention strategies for AF patients with moderate to severe MS.
- Findings will inform clinical practice guidelines regarding the use of NOACs in this underserved population.
- Results will be disseminated through peer-reviewed publications.
Introduction:
Current international guidelines recommend non-vitamin K oral anticoagulants (NOACs) for stroke prevention among patients with non-valvular atrial fibrillation (AF) at significant ischaemic stroke risk given the superior safety and comparable efficacy of NOACs over warfarin. Nonetheless, the safety and effectiveness of NOACs have not been evaluated in patients with AF with underlying moderate or severe mitral stenosis (MS), hence the recommended stroke prevention strategy remains warfarin therapy.
Method And Analysis:
MS remains disproportionately prevalent in Asian countries compared with the developed countries. This prospective, randomised, open-label trial with blinded endpoint adjudication aims to evaluate the safety and efficacy of dabigatran for stroke prevention in AF patients with moderate or severe MS. Patients with AF aged ≥18 years with moderate or severe MS not planned for valvular intervention in the coming 12 months will be randomised in a 1:1 ratio to receive dabigatran 110 mg or 150 mg two times per day or warfarin with international normalised ratio 2-3 in an open-label design. Patients with estimated creatinine clearance <30 mL/min, or with a concomitant indication for antiplatelet therapy will be excluded. The primary outcome is a composite of stroke and systemic embolism. Secondary outcomes are ischaemic stroke, systemic embolism, haemorrhagic stroke, intracranial haemorrhage, major bleeding and death. The estimated required sample size is approximately 686 participants.
Ethics And Dissemination:
The study protocol has been approved by the Institutional Review Board of the University of Hong Kong and Hong Kong West Cluster, Hospital Authority, Hong Kong for Fung Yiu King Hospital, Grantham Hospital, Queen Mary Hospital and Tung Wah Hospital in Hong Kong. Results will be published in peer-reviewed journals.
Trial Registration Number:
ClinicalTrials.gov Registry (NCT04045093); pre-results.
Related Concept Videos
01:18Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...
01:26Mitral Stenosis III: Medical Management
01:20Antiplatelet Drugs: Prostaglandin Synthesis, P2Y12 and Glycoprotein IIb/IIIa Inhibitors
Prostaglandin synthesis inhibitors, exemplified by the widely known aspirin, wield their power by irreversibly acetylating...
01:30Anticoagulant Drugs: Low-Molecular-Weight Heparins
01:29Venous Thrombosis III: Interprofessional Care
01:23Mitral Stenosis II: Clinical features and Diagnostic Tests