DIscontinuation of Anticoagulation Guided by Smartwatch in Post-ablation Patients with Atrial Fibrillation

Not Applicable

Not yet recruiting

• Conditions: Atrial Fibrillation (AF)
• Interventions: Device: PPG/ECG dual mode based smartwatch; Drug: Continuous DOAC therapy

• Registration Number: NCT06871228
• Lead Sponsor: Beijing Anzhen Hospital

Brief Summary

The DIAMOND-AF trial, an investigator-initiated multicenter study, randomizes 5,694 stroke-free AF patients with a CHA₂DS₂-VA score of 2-6 post-successful ablation to either smartwatch-guided intermittent direct oral anticoagulant (DOAC) therapy (30-day treatment triggered by AF episodes ≥1 hour single or ≥2 hours/24h) or continuous DOAC therapy. The trial assesses the superiority of intermittent DOAC therapy in reducing major bleeding (ISTH) compared to continuous DOAC therapy, and the non-inferiority of intermittent DOAC in preventing thromboembolism (stroke, embolism, and cardiovascular death) over a 48-month follow-up, aiming to tailor anticoagulation strategies in patients with rhythm control achieved through ablation.

Detailed Description

The DIAMOND-AF trial is an investigator-initiated, multicenter, randomized open-label study designed to address anticoagulation uncertainty in 5,694 atrial fibrillation (AF) patients with CHA₂DS₂-VA scores 2-6 who maintain sinus rhythm ≥3 months post-ablation. Participants are randomized 1:1 to receive either NMPA-cleared smartwatch-guided intermittent DOAC (30-day DOAC therapy initiated within 24h of photoplethysmography-detected AF recurrence ≥1-hour single episode or ≥2 hours/24h) or continuous DOAC therapy per current guidelines. The co-primary endpoints evaluate: 1) superiority in reducing ISTH-defined major bleeding events over 48 months, and 2) non-inferiority in preventing composite thromboembolism (ischemic stroke, systemic embolism, and cardiovascular death). Endpoints were assessed through blinded endpoint adjudication committees. This trial pioneers an individualized medicine approach by integrating consumer-grade wearable technology with dynamic anticoagulation, potentially tailoring post-ablation management for high-risk AF populations through dual validation of both arrhythmia detection accuracy (PPG vs ECG) and event-driven anticoagulation efficacy.

Study Timeline

• Status Verified: 2025-02
• Study First Submitted: 2025-02-26
• Study First Submitted QC: 2025-03-05
• Last Update Submitted: 2025-03-05
• Study First Posted: 2025-03-11
• Last Update Posted: 2025-03-11
• Study Start: 2025-07-01
• Primary Completion: 2029-12-31
• Study Completion: 2029-12-31

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 5694

Inclusion Criteria

1. Age 18-80 years.
2. No recurrence of atrial arrhythmia within 3 months after the most recent AF/atrial flutter catheter ablation.
3. CHA₂DS₂-VA score of 2-6.
4. Voluntarily sign informed consent to participate in the study.
5. Willingness and ability to comply with the study protocol.

Exclusion Criteria

1. Non-compliance with prescribed DOACs or antiarrhythmic drugs (AADs), or failure to undergo protocol-mandated 24-hour Holter monitoring for rhythm assessment within 3 months post-ablation.

2. Premature atrial complex or premature ventricular complex burden >10% on any 24-hour Holter within 3 months after ablation.

3. Moderate-to-severe mitral stenosis (mitral valve area ≤ 2.0 cm²) or mechanical heart valves.

4. History of stroke, transient ischemic attack, systemic embolism, or left atrial thrombus.

5. Conditions associated with an increased risk of bleeding:

   1. History of major non-traumatic bleeding events (e.g., intracranial, intraocular, retroperitoneal, gastrointestinal, or intra-articular bleeding), unless reversible causes have been permanently eliminated;
   2. Untreated intracranial aneurysms, vascular malformations, or gastrointestinal ulcers;
   3. Surgery involving general anesthesia within the last 3 months or planned surgery within the next 3 months;
   4. Bleeding disorders (e.g., hemophilia);
   5. Uncontrolled hypertension (systolic BP > 180 mmHg or diastolic BP > 110 mmHg);
   6. Hemoglobin < 90 g/L or history of blood transfusion within 4 weeks prior to enrollment;
   7. Severe thrombocytopenia (platelet count < 50 × 10⁹/L);
   8. Stage 5 chronic kidney disease (eGFR < 15 ml/min/1.73m²) or dialysis;
   9. Severe liver disease (e.g., esophageal varices, ascites, hepatic encephalopathy, or jaundice);
   10. Known intolerance or contraindications to DOACs.

6. Presence of a cardiac implantable electronic device or indication for a permanent pacemaker, implantable cardioverter-defibrillator (ICD), or cardiac resynchronization therapy (CRT).

7. Conditions requiring long-term anticoagulation (e.g., pulmonary embolism, deep vein thrombosis, hypertrophic cardiomyopathy, or amyloidosis).

8. High risk for non-cardiogenic stroke (e.g., carotid artery stenosis > 70%).

9. Currently on warfarin and unwilling or unable to switch to a DOAC.

10. Currently on dual antithrombotic therapy (e.g., dual antiplatelet therapy or anticoagulant plus antiplatelet therapy).

11. Left atrial appendage (LAA) occlusion, LAA closure, or confirmed LAA electrical isolation.

12. Woman who is pregnant and/or breastfeeding.

13. Life expectancy of less than 2 years.

14. Presence of tattoos, birthmarks, surgical scars, or tremors (e.g., Parkinson's disease, benign essential tremor) in the wrist area that may interfere with PPG monitoring.

15. Participation in another interventional clinical trial.

16. Any condition that, in the investigator's judgment, makes the participant unsuitable for the study.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Smart Watch-Guided Intermittent DOAC	PPG/ECG dual mode based smartwatch	Participants randomized to the intervention arm will be provided with a PPG-based smartwatch that continuously monitors their rhythm and an app to remind wearing the watch for at least 12 hours per day and taking DOAC on time, and follow-up. If AF is suspected based on the PPG data, the smartwatch will notify the participant to take an ECG. Both the participant and the coordinating center will be notified if a threshold AF event occurs.
Continuous DOAC Therapy	Continuous DOAC therapy	Participants randomized to the control arm will remain on previously prescribed DOAC therapy, in line with current clinical practice. These participants will continue taking DOAC throughout the study as prescribed by their physicians unless contraindicated. They will also use the app for reminders regarding DOAC use and follow-up but will not receive the smartwatch.

Primary Outcome Measures

Name	Time	Method
To assess whether smartwatch-guided, tailored DOAC therapy is superior to continuous DOAC therapy in reducing major bleeding and non-inferior in preventing a composite endpoint of: (1) ischemic stroke, (2) systemic embolism, and (3) cardiovascular death.	over 48 months	The primary safety outcome is to evaluate if smartwatch-guided, tailored DOAC therapy is superior to continuous DOAC therapy for major bleeding events, defined by ≥1 ISTH criteria: (1) fatal bleeding; (2) symptomatic bleeding in a critical organ; (3) bleeding causing a hemoglobin drop ≥20 g/L or requiring ≥2 units of blood transfusion.; The primary effectiveness outcome is to assess if smartwatch-guided, tailored DOAC therapy is non-inferior to continuous therapy for a composite endpoint: (1) ischemic stroke; (2) systemic embolism; (3) cardiovascular death.; Ischemic stroke is defined as an acute focal dysfunction from CNS infarction lasting ≥24h, with potential hemorrhagic transformation. Systemic embolism refers to arterial embolism or thrombosis (excluding stroke or TIA). Cardiovascular death includes deaths from heart failure, shock, valve dysfunction, myocardial infarction, stroke, thromboembolism, bleeding, arrhythmia, infection, or complications during a cardiovascular procedure.

Secondary Outcome Measures

Name	Time	Method
Ischemic stroke	over 48 months
Systemic embolism	48 months
Cardiovascular death	48 months
Major bleeding	48 months
All-cause death	48 months	All-cause death is defined as death resulting from the underlying disease or injury that initiates the sequence of events leading to death.
Clinically relevant non-major bleeding	48 months	Clinically relevant non-major bleeding is defined as any sign or symptom of hemorrhage that does not meet the criteria for the ISTH definition of major bleeding, but meets at least one of the following criteria: 1. Requiring medical intervention by a healthcare professional.; 2. Leading to hospitalization or increased level of care.; 3. Prompting a face-to-face evaluation by a healthcare provider.
Atrial Fibrillation Effect on Quality-of-Life questionnaire (AFEQT) score	48 months	The AFEQT score ranges from 0 to 100, with higher scores indicating better QoL.
Five-Level EuroQol Five Dimensions Questionnaire (EQ-5D-5L) score	48 months	The EQ-5D-5L measures health-related quality of life. It has two parts: 1) a 5-dimension descriptive system (mobility, self-care, usual activities, pain, anxiety/depression) with 5 levels per dimension, generating a utility value; 2) a Visual Analogue Scale (VAS) from 0 (worst) to 100 (best) for overall health. Higher scores indicate better health.
Generalized Anxiety Disorder-7 item questionnaire (GAD-7) score	48 months	Anxiety is measured by GAD-7 score, with scores ranging from 0 to 21, where higher scores indicate greater levels of anxiety.
Patient Health Questionnaire-9 item questionnaire (PHQ-9) score	48 months	Depression is evaluated using PHQ-9 score, which is scored from 0 to 27, with a higher score indicating greater levels of depression.
Total time of using DOAC	48 months	Total time of using DOAC is defined as the cumulative days during which the patient is prescribed and adheres to DOAC therapy throughout the study.

Trial Locations

Locations (2)

Beijing Anzhen Hospital; 🇨🇳 Beijing, Beijing, China

Sir Run Run Shaw Hospital, Zhejiang University School of Medicine; 🇨🇳 Hangzhou, Zhejiang, China