CPVI Alone Versus. CPVI Plus Electrophysiological Substrate Ablation in the LA During SR for the Treatment of Non-PAF

Inclusion Criteria: * Patients age is 18-80 years; * Patients with non-paroxysmal AF; non-paroxysmal AF will be defined as a sustained episode lasting \> 7 days; * Patients can sign the written informed consent for the study; * Patients can endure the required follow-up. Exclusion Criteria: * Patients with previous radiofrequency ablation; * Patients with PLT count less than 80×109/L, or with contraindications to systemic anticoagulation with heparin or Coumadin or a direct thrombin inhibitor; * Patients with left atrial size ≥ 55 mm (2D echocardiography, parasternal long-axis view); * Patients with thromboemboli in LA (TEE or MSCT); * Patients with severe structural cardiac disease (medium or severe mitral regurgitation, DCM, HCM, or other severe valvular heart diseases); * Patients with abnormal thyroid function; * Patients with severe liver or renal dysfunction (AST or ALT \> 3-fold of upper limit value; the SCr \> 3.5 mg/dl or Ccr \< 30 ml/min); * Previous surgery history in last 3 months; * Patients with life expectancy \< 12 months; and * Patients who are pregnant.