Inclusion Criteria:  Aged 18 to 80 years old Persistent AF with severe atrial fibrosis Nonresponse or intolerance to ≥1 antiarrhythmic drug CHA2DS2-VASc ≥ 3 and HAS-BLED < 3  Exclusion Criteria:  With uncontrolled congestive heart failure; Having significant valvular disease; Having moderate-to-severe pulmonary hypertension; With myocardial infarction or stroke within 6 months of screening; With Significant congenital heart disease; Ejection fraction was <40% measured by echocardiography; Allergic to contrast media; Contraindication to anticoagulation medications; Severe pulmonary disease e.g. restrictive pulmonary disease, chronic obstructive disease (COPD); Left atrial thrombus; Having any contraindication to right or left sided heart catheterization