Dabigatran for Mitral Stenosis Atrial Fibrillation (David-MS)

Rationale and Design of Dabigatran for Mitral Stenosis Atrial Fibrillation Trial

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 atrial fibrillation (AF) at significant ischemic stroke risk, given the superior safety and comparable efficacy of NOACs over warfarin. However, the safety and efficacy of NOACs had not been evaluated in AF patients with underlying mitral stenosis (MS) thereby the currently recommended stroke prevention strategy remains warfarin therapy for AF patients with underlying MS. A local study is initiated to compare efficacy and safety of Dabigatran with Warfarin therapy in AF patients with moderate to severe MS.

Study Overview

• Status: Active, not recruiting
• Conditions: Atrial Fibrillation; Mitral Stenosis
• Intervention / Treatment: Drug: Dabigatran etexilate; Drug: Warfarin

Detailed 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 was 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. Nonetheless off-label use of NOACs in patients with MS is not uncommon in the real world practice.

This is of particular importance for Asian AF patients, in whom MS remains relatively prevalent despite a declining trend. More importantly, the much higher baseline risk of intracranial haemorrhage and apparently higher ischemic stroke risk in Asian populations potentially undermine the benefits of Warfarin therapy. On the other hand, the efficacy and safety of NOACs compared with Warfarin appear to be even higher in Asian population than the non-Asian population as shown in sub-analyses pivotal randomised control trials as well as in the real world evidence. 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 MS.

After providing written informed consent, study participants from participating local centres 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. In a year of individual study period, vital signs, laboratory blood check and adverse events will be monitored, and primary and secondary outcomes will be assessed. The estimated sample size is approximately 370 participants. On addition, a subgroup of patients up to 10% of the target sample size will be invited for an one-time non-invasive magnetic resonance imaging (MRI) for assessment of any intra-cardiac thrombus.

The results will be an important contribution to the stroke prevention strategy for patients with MS 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.

• Study Type: Interventional
• Enrollment (Estimated): 370
• Phase: Phase 4

Contacts and Locations

Study Locations

• Hong Kong
  • Hong Kong, Hong Kong
    • The University of Hong Kong / Queen Mary Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients with atrial fibrillation documented with standard 12-lead ECG documented atrial fibrillation on the day of screening or randomization
• Patients with age ≥ 18 years
• Patients with moderate or severe mitral stenosis, i.e. mitral valvular area (MVA) ≤ 2.5cm2
• Patients should be able to provide a written informed consent
• Patients should have all 4 inclusion-criteria fulfilled to be qualified for the study

Exclusion Criteria:

• Patients with mechanical prosthetic valve, or with active endocarditis
• Patients with planned valvular intervention within 1 year
• Patients with left atrial appendage occlusive device
• Patients with planned AF ablation
• Unexplained anemia (haemoglobin level < 10g/dL) or thrombocytopenia (platelet count < 100x10*9/L)
• Need for anticoagulant therapy of disorders other than atrial fibrillation
• Patients receiving antiplatelet therapy for disorders other than atrial fibrillation
• Uncontrolled hypertension (systolic blood pressure > 180mmHg and/or diastolic blood pressure > 100mmHg)
• Estimated creatinine clearance ≤ 30mL/min
• Liver dysfunction of Child Pugh stage B or C
• Women who are pregnant or of childbearing potential who refuse to use a medically acceptable form of contraception throughout the study
• Patients considered unreliable by the investigator or have a life expectancy less than 1 year because of concomitant disease, or has any condition, which in the opinion of the investigator, would not allow safe participation in the study (e.g. drug addiction, alcohol abuse)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Warfarin; Subjects randomized into this group will be prescribed with Warfarin with dosage adjustment according to INR level (targeting to INR 2-3) for stroke prevention.	Drug: Warfarin; Subjects will be randomized into 2 groups in a 1:1 ratio, to receive either Dabigatran or Warfarin for stroke prevention, in a open-label design.
Experimental: Dabigatran etexilate; Subjects randomized into this group will be prescribed with either Dabigatran 150mg or Dabigatran 110mg (twice daily) according to creatinine clearance level) for stroke prevention.	Drug: Dabigatran etexilate; Subjects will be randomized into 2 groups in a 1:1 ratio, to receive either Dabigatran or Warfarin for stroke prevention, in a open-label design.; Other Names: Pradaxa

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Composite of stroke, systemic embolism, myocardial infarction, and death from cardiovascular or unknown cause.	Stroke is classified into ischemic or hemorrhagic stroke, as confirmed by computed tomography or magnetic resonance imaging. Systemic embolism is defined as an acute vascular occlusion of an extremity or organ other than the brain, documented by imaging, surgery, and/or autopsy. Myocardial infarction is defined according to the latest ACC/AHA/ACEP/NAEMSP/SCAI guideline for the management of patients with acute coronary syndromes, with the assessment of electrocardiography, cardiac troponin values and presence of symptoms. Death is counted when subject is medically certified of death, resulted from cardiovascular or unknown cause.	1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Systemic embolism	It is defined as an acute vascular occlusion of an extremity or organ other than the brain, documented by imaging, surgery, and/or autopsy.	1 year
Ischemic stroke	It is defined as the first episode during follow-up of new-onset of neurological symptoms attributable to a cerebral infarct, as confirmed by computed tomography or magnetic resonance imaging, lasting more than 24 hours.	1 year
Hemorrhagic stroke	It is defined as the first episode during follow-up of new-onset of neurological symptoms attributable to an intraparenchymal or subarachnoid hemorrhage, as confirmed by computed tomography or magnetic resonance imaging.	1 year
Major bleeding	Bleeding being categorized as BARC type 3 or higher is regarded as major bleeding.	1 year
Death	It is counted when subject is medically certified of death.	1 year

Collaborators and Investigators

• Sponsor: The University of Hong Kong
• Investigators: Principal Investigator: Siu Han Jo Jo Hai, Bachelor, The University of Hong Kong

Publications and helpful links

General Publications

• Zhou M, Chan EW, Hai JJ, Wong CK, Lau YM, Huang D, Lam CC, Tam CCF, Wong YTA, Yung SYA, Chan KWK, Feng Y, Tan N, Chen JY, Yung CY, Lee KL, Choi CW, Lam H, Ng A, Fan K, Jim MH, Yiu KH, Yan BP, Siu CW. Protocol, rationale and design of DAbigatran for Stroke PreVention In Atrial Fibrillation in MoDerate or Severe Mitral Stenosis (DAVID-MS): a randomised, open-label study. BMJ Open. 2020 Sep 25;10(9):e038194. doi: 10.1136/bmjopen-2020-038194.

Study record dates

Study Major Dates

• Study Start (Actual): October 22, 2020
• Primary Completion (Estimated): September 30, 2026
• Study Completion (Estimated): September 30, 2027

Study Registration Dates

• First Submitted: August 2, 2019
• First Submitted That Met QC Criteria: August 2, 2019
• First Posted (Actual): August 5, 2019

Study Record Updates

• Last Update Posted (Estimated): December 17, 2025
• Last Update Submitted That Met QC Criteria: December 12, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Heart Valve Diseases; Pathological Conditions, Signs and Symptoms; Atrial Fibrillation; Mitral Valve Stenosis; Pyridines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Benzimidazoles; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Pyrans; Coumarins; Benzopyrans; 4-Hydroxycoumarins; Dabigatran; Warfarin
• Other Study ID Numbers: DAMS-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data will be available on request to the corresponding author

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No