Pulmonary vein isolation (PVI) has become a standard therapy for atrial fibrillation (AF), however, there is still considerable AF recurrence after PVI. Except for PV-left atrium (LA) reconnection, the cause of recurrence has been not yet fully clarified.

The alternation of autonomic tone plays an important role in initiation of paroxysmal AF. It was reported that there are multiple gangliated plexus (GP) around pulmonary veins, therefore the modulation targeting those GPs, resulting in modulations of cardiac autonomic tone, have been conducted. Some study showed the efficacy of GP ablation for AF patients.

According to the previous reports, heart rate (HR) increased, and heart rate variability (HRV) reduced after PVI. These are considered to be due to "autonomic denervation" caused by catheter ablation of GP.

For the best of investigators knowledge, there have been no data on heart rate turbulence (HRT) of baroreflex sensitivity (BRS) concerning PVI.

Inclusion Criteria:

• Patients who undergo PVI for paroxysmal atrial fibrillation
• Patients in sinus rhythm at baseline

Exclusion Criteria:

• prior left atrial Ablation
• left atrial diameter >55mm
• frequent atrial extrasystole, frequent ventricular Extrasystole
• Diabetes Mellitus
• sleep apnea syndrome

Patients who undergo PVI for paroxysmal AF