To compare the efficacy of different procedures, identify the optimal procedure, ablation sites, ablation endpoints and post-operative anticoagulation strategy, establish the optimal treatment strategy for atrial fibrillation.

Inclusion Criteria:

1. Atrial fibrillation recorded by ECG or Holter;
2. Age: 18 ~ 75 years;
3. Patients who are willing to enroll in the trial

Exclusion Criteria:

1. Patients accompanied hyperthyroidism;
2. Patients with sever liver or renal dysfunction;
3. Patients with sever cardiac dysfunction;
4. Patients had previous radiofrequency catheter ablation in the LA or Maze surgical procedure;
5. Patients with emboli in atrium;
6. Pregnant woman