Objectives: This pilot study aims to evaluate the safety and efficacy of left atrial appendage occlusion (LAAO) in dialysis patients and atrial fibrillation (AF) to establish a novel stroke prevention strategy and determine an optimal post-occlusion antithrombotic regime. Page 3 of 50 Hypothesis: The study tests the hypotheses that LAAO is safe for dialysis patients, that a single antiplatelet regimen postprocedure is safe, and that LAAO effectively reduces the composite endpoint of stroke/transient ischemic attack and major bleeding compared to standard care. Instruments: The study employs a multicenter, single-arm prospective registry design. Eligible participants, aged ≥18 with documented AF and ESRF on peritoneal dialysis (PD) or hemodialysis (HD), will undergo LAAO using the Watchman Flx PRO device. Propensity score matched historical cohort from dialysis registry will be identified for comparison.

Main Outcome Measures: The primary endpoint is the composite of stroke/transient ischemic attack/systemic embolism and non-procedural-related major bleeding at one year. Secondary endpoints include individual rates of these events, procedural safety and device occlusion effectiveness. Data Analysis and Expected Results: Statistical analysis will involve descriptive statistics, chi-squared tests, and propensity score matching. A p-value of <0.05 will be deemed significant. The pilot study anticipates a low peri-procedural complication rate (≤5%) and confirms LAAO's efficacy in stroke and major bleeding reduction in Chinese PD and HD patients compared to standard care. This data will inform the design of a larger randomized controlled trial aimed at validating LAAO as a safe alternative for AF management in dialysis populations.

Inclusion Criteria:

• Age >=18
• End stage renal failure on peritoneal dialysis or haemodialysis
• documented paroxysmal, persistent, or permanent non-valvular atrial fibrillation;
• CHADS2-VASc >=2
• The patient is willing and able to comply with the required medication post-procedure and follow-up evaluations;
• Able to consent

Exclusion Criteria:

• Patients who require long-term anticoagulation for a condition other than AF, e.g. pulmonary embolism, deep vein thrombosis, anti-phospholipid syndrome

• Mechanical valve replacement

• Active infection with bacteraemia;

• Pregnant or nursing patients and those who plan pregnancy during the study period. Female patients of childbearing potential must have a negative pregnancy

• Known hypersensitivity or contraindication to aspirin, clopidogrel, heparin, any device material or component (nickel titanium, PET, polypropylene), and/or contrast;

• Left atrial appendage is obliterated and surgical ligated;

• Underwent any cardiac or non-cardiac interventional or surgical procedure within 30 days prior to the procedure or planned to have the interventional or surgical procedure within 60 days after implant procedure (e.g., cardioversion, ablation, percutaneous coronary intervention, etc.);

• Recent (within 90 days prior to procedure) stroke, transient ischemic attack, or myocardial infarction;

• New York Heart Association Class IV;

• Life expectancy is less than 1 year;

• Current participation in another investigational drug or device study.

• Echocardiogram exclusion:

  i. Moderate mitral stenosis or above ii. LVEF <30% iii. Intracardiac thrombus iv. Presence of a cardiac tumour. v. Existing circumferential pericardial effusion >5 mm; vi. Presence of a high-risk Patent Foramen Ovale (PFO), defined as an atrial septal aneurysm (excursion >15 mm or length >15 mm) or large shunt (early, within 3 beats and/or substantial passage of 20 bubbles)

The study employs a multicenter, single-arm prospective registry design. Eligible participants, aged ≥18 with documented AF and ESRF on peritoneal dialysis (PD) or hemodialysis (HD), will undergo LAAO using the Watchman Flx PRO device. Propensity score matched historical cohort from dialysis registry will be identified for comparison.