Exploratory Observation of Regimens After LAA Occlusion by LAMax LAAC® Device for Subjects With High Risk of Bleeding

This is a prospective, single-center, randomized, exploratory clinical observation to explore the overall benefit of optimized anticoagulation and antithrombotic regimens after left atrial appendage occlusion by LAMax LAAC® occluder for subjects with non-valvular atrial fibrillation (AF) at high risk of bleeding (HAS-BLED score ≥ 3).

Inclusion Criteria:1. Patients ≥ 18 years old with non-valvular atrial fibrillation (AF) and CHA2DS2-VASc ≥2;2. Patients not suitable for long-term standardized anticoagulation, or stroke /embolic events still occurred on the basis of long-term standardized anticoagulation;3. HAS-BLED ≥ 3;4. Successful left atrial appendage occlusion with LAMax LAAC® device;5. Patients and their families fully understand the purpose of the study, voluntarily participate in the study and sign the informed consent form.Exclusion Criteria:1. Combined with other diseases except AF requiring long-term warfarin or other anticoagulant therapy;2. Absolute contraindications for anticoagulation therapy or unacceptable bleeding risk with dual antiplatelet therapy;3. Indications to dual antiplatelet therapy other than atrial fibrillation and/or left atrial appendage occlusion at the time of enrollment or predicted appearance of such indications within the duration of the trial (e.g. planned coronary revascularization);4. Occluder dislocation, pericardial effusion (including new pericardial effusion and significantly increased pre-existing pericardial effusion) and other bleeding complications within 24 hours after LAAC;5. Patients scheduled for catheter ablation after left atrial appendage electrical isolation and during the study;6. Patients resistant to clopidogrel;7. Patients requiring elective cardiac surgery;8. Heart failure NYHA grade IV and not been corrected yet;9. Patients with AF caused by rheumatic valvular heart disease, degenerative valvular heart disease, congenital valvular heart disease, severe mitral stenosis, aortic stenosis and other valvular diseases;10. Initial atrial fibrillation, paroxysmal atrial fibrillation with a clear cause such as coronary artery bypass grafting (CABG) < 12 months, hyperthyroidism, etc.11. Patients with acute myocardial infarction or unstable angina pectoris, or recent myocardial infarction < 12 months;12. Patients with active bleeding, bleeding constitution or bleeding disorders, coagulation history and unhealed gastrointestinal ulcer;13. Infective endocarditis, vegetation or other infections causing bacteremia, sepsis;14. Female patients who are pregnant, lactating, or planning to become pregnant during this study;15. Patients who have participated in other drug or device clinical trials and have not reached the endpoint;16. Patients with renal insufficiency (endogenous creatinine clearance < 30ml/min) (using the standard Crockcroft-Gault formula) and/or advanced renal disease requiring dialysis;17. Severe hepatic dysfunction (AST/ALT greater than 5 times the upper limit of normal or total bilirubin greater than 2 times the upper limit of normal);18. Patients considered unsuitable for this study by the investigator.19. Left atrial appendage has been removed, post heart transplantation, post atrial septal repair, or post occluder implantation;20. Post prosthetic heart valve replacement;21. Allergic to or contraindication to metal nickel alloy, aspirin, clopidogrel, contrast agent, heparin and other anticoagulants, etc;22. Patients who have placed other instruments in the cardiovascular cavity and are unable to place the LAA occluder;23. LVEF（left ventricular ejection fraction, by Simpson method）<35%；24. Clear thrombus is found in the heart before LAAC;25. TEE examination: the maximal orifice diameter of LAA is less than 12 mm, or more than 36 mm;26. Residual flow after LAAC >5mm；27. Patent foramen ovale with high risk;28. Mitral stenosis with a valve area <1.5cm2;29. Left atrial diameter (antero-posterior diameter) > 65mm, or pericardial effusion more than a small amount, the depth of local effusion > 10 mm;30. Contraindications to X-ray, or not suitable for TEE examination.