Study of Atrial Fibrillation Combined with Atrial Functional Mitral Regurgitation

Inclusion Criteria: 1. Patients aged 18 to 80 years old; 2. Patients diagnosed with symptomatic paroxysmal atrial fibrillation (AF history \< 5 years) 3. Moderate to severe MR and normal LV ejection fraction (≥50%), LVEDD\<55 mm, and normal LV wall systolic function 4. Able to understand the purpose of the trial, participate in the trial voluntarily with informed consent form signed by the subject him/herself or his or her legal representative, and willing to complete follow-up visits as required under the protocol Exclusion Criteria: 1. Atrial fibrillation secondary to electrolyte imbalances, thyroid disease or other reversible factors 2. Active endocarditis or active rheumatic heart disease, or degenerative mitral regurgitation due to endocarditis or rheumatic valvular heart disease 3. Moderate to severe mitral stenosis 4. Imaging examination shows left atrium or left atrial appendage thrombosis 5. Left ventricular ejection fraction less than 50% 6. Left atrial diameter more than 50mm 7. Patients with previous left atrial appendage occlusion or left atrial appendage closure, patent foramen ovale closure, atrial septal defect closure or repair (only applied for patients who need to ablation) 8. Patients who have implanted devices such as implantable cardioverter defibrillator(ICD), cardiac resynchronization therapy(CRT) or pacemaker 9. Previous metal artificial valve or valve repair device implantation (only applied for patients who need to ablation) 10. Presence of lateral thrombus, tumors or other abnormalities that interfere with vascular puncture or catheter operation (only applied for patients who need to ablation) 11. Anticoagulation contraindications, and history of blood clotting or bleeding abnormalities 12. Acute systemic infection 13. Female patients who are pregnant, lactating, or unable to use contraception during the study 14. Patients' life expectancy is less than 12 months 15. Abnormalities or diseases that the investigator believes should be excluded from the scope of enrollment in this study