Discontinuation of Anticoagulation With Intensive Rhythm Monitoring in Post-ablation Patients With Atrial Fibrillation

Overview

DIAMOND-AF is a multicenter, randomized, open-label trial evaluating whether discontinuing oral anticoagulation after successful atrial fibrillation ablation can reduce bleeding risk without increasing death or thromboembolism risks. Adults aged 18-80 years, 60-365 days post-ablation, with CHA2DS2-VA ≥2, no prior stroke/TIA/systemic embolism, continuous NOAC use, and no documented atrial tachyarrhythmia recurrence will be randomized 1:1 to stop NOACs immediately or to continue NOAC therapy. All participants use intensified rhythm surveillance including smartwatch ECG and Holter/patch monitoring (at least every 6 months; every 2 months encouraged) to detect recurrence. Co-primary endpoints are (1) non-inferiority for the composite of all-cause death, ischemic stroke, or systemic embolism and (2) superiority for the composite of ISTH major bleeding or ISTH clinically relevant non-major bleeding. The planned sample size is 4,100 participants.

DIAMOND-AF is an investigator-initiated, multicenter, randomized, open-label, parallel-group trial designed to evaluate post-catheter ablation anticoagulation management in patients with atrial fibrillation (AF/AFL). The trial will enroll adults aged 18-80 years who are 60±15 to 365±15 days after AF ablation, have a CHA2DS2-VA score ≥2, have no history of ischemic stroke/transient ischemic attack/systemic embolism, have been continuously taking a non-vitamin K antagonist oral anticoagulant (NOAC), and have no documented atrial tachyarrhythmia recurrence after ablation. Eligible participants will be randomized 1:1 to (1) discontinue NOAC immediately after randomization or (2) continue NOAC therapy. The study uses a co-primary endpoint strategy: a non-inferiority assessment for the composite efficacy endpoint (all-cause death, ischemic stroke, or systemic embolism) and a superiority assessment for the composite safety endpoint (ISTH major bleeding or ISTH clinically relevant non-major bleeding). To maximize safety while testing an anticoagulation-discontinuation strategy, all participants will undergo intensified rhythm monitoring using a smartwatch capable of single-lead ECG plus scheduled Holter/single-lead ECG patch monitoring (at least every 6 months; every 2 months encouraged), with symptom-triggered and opportunistic ECGs incorporated. AF Recurrence is defined as any ECG-confirmed atrial tachyarrhythmia (AF/AFL/atrial tachycardia) lasting ≥30 seconds; once AF recurrence is confirmed, the participant will be censored and will exit further trial follow-up. Participants will have in-person/structured study visits at months 3 and 6 after randomization, then every 6 months, with additional rhythm/anticoagulation follow-up every 2 months. The planned sample size is 4,100 participants (2,050 per group).