Dabigatran for Mitral Stenosis Atrial Fibrillation

Atrial Fibrillation Clinical Trial

Official title: Rationale and Design of Dabigatran for Mitral Stenosis Atrial Fibrillation Trial

Status Recruiting

Clinical Trial Summary

Atrial fibrillation (AF) is the most common sustained cardiac arrythmia encountered in clinical practice and patients suffer from this are at increased risk of ischemic stroke and systemic thromboembolism due to the formation and embolism of left atrial thrombi. Current international guidelines recommend non-vitamin K oral anticoagulants (NOACs) for stroke prevention amongst these patients with non-valvular AF at significant ischemic stroke risk, given the superior safety and comparable efficacy of NOACs over warfarin. However, warfarin therapy remains in the stroke prevention strategy for AF patients with mitral stenosis (MS) as NOACs lack of evidence for safety and efficacy amongst this group of patients. A local study is initiated to compare and evaluate the safety and efficacy among the two groups of anticoagulants - NOACs and traditional Warfarin therapy - in AF patients with underlying moderate to severe MS.

Clinical Trial Description

While the stroke risk amongst AF patients appears heterogeneous, patients with underlying valvular heart diseases particularly MS are at very high risk for stroke if left un-anticoagulated. However, this group of patients were typically excluded in randomized control trials. As a result, current international guidelines for management of AF do not recommend NOACs for stroke prevention in AF patients with underlying moderate or severe MS.

In a stark contrast to developed countries, mitral stenosis remains prevalent in many Asian countries. Together with the much higher intracranial haemorrhage risk in Asians on Warfarin, NOACs appear to be a very attractive and promising alternative. Nonetheless off-label use of NOACs in patients with MS is not uncommon in the real world practice. This study refers as a prospective, randomized, open-label trial with blinded end-point adjudication, aiming at evaluating the safety and efficacy of Dabigatran for stroke prevention in AF patients with underlying moderate or severe mitral stenosis.

Subjects enrolled in this study will be randomized into 2 groups in a 1:1 ratio, to receive either Dabigatran (150mg or 110mg according to creatinine clearance level, twice daily) or Warfarin (targeting in the international normalized ratio (INR) range 2-3) in an open-label design. Primary and secondary outcomes will be assessed, including ischemic stroke, systemic embolism, haemorrhagic stroke, intracranial haemorrhage, major bleeding and death. The estimated sample size is approximately 686 participants.

The results will contribute to the stroke prevention strategy for patients with mitral stenosis and may be immediately translatable to real clinical practice. Ultimately, this study will provide the necessary evidence for establishing universal guidelines for this group of patients. ;

Related Conditions & MeSH terms

• Atrial Fibrillation
• Constriction, Pathologic
• Mitral Stenosis
• Mitral Valve Stenosis

• NCT number: NCT04045093
• Study type: Interventional
• Source: The University of Hong Kong
• Contact: Chun Ka Wong, Clinical Assistant Professor
• Phone: +852-22553597
• Email: wongeck@hku.hk
• Status: Recruiting
• Phase: Phase 4
• Start date: October 22, 2020
• Completion date: September 30, 2027