Mesh-type flexible tip (MFT) catheter is developed to generate bigger radiofrequency (RF) lesion, and contract force (CF) catheter improves the maintenance of catheter-tissue contact during atrial fibrillation catheter ablation (AFCA).

The investigators compared clinical outcome of AFCA conducted by MFT catheter and CF catheter in prospective randomized manner.

The investigators prospectively assigned 230 patients with AF in a 1:1 ratio to ablation by MFT catheter (FlexAbility™, Abbott Inc. USA) and CF catheter (TactiCath™, Abbott Inc. USA). The primary end point was AF recurrence after single procedure, and the secondary end point was response to antiarrhythmic drugs.

A. Study design

1. Prospective randomization (FlexAbility group vs. TactiCath group )
2. Target number of subjects: 360 (180 per group)
3. Rhythm follow-up : 2012 ACC/AHA/ESC guidelines (Holter monitoring at the baseline, 2 month, and thereafter every 6 months; ECG if the patient has any symptom)
4. Anticoagulant therapy followed by 2014 ACC/AHA/ESC guidelines
5. All complications in each group will be evaluated including the re-hospitalization rate, cardioversion frequency, major cardiovascular event, and mortality rate.

B. Progress and rhythm/ECG follow-up

1. To be performed in accordance with the 2012 ACC/AHA/HRS guidelines for AF management
2. Follow-up at 2 weeks, 2 months, and thereafter every 6-month.
3. Rhythm control at 2 months, and thereafter every 6-month follow-up with Holter
4. If the patient complains of symptoms, ECG will be performed at any time, and rhythm follow-up will be carried out with a Holter or event recorder.

Inclusion Criteria:

• Appropriate indiction for AF catheter ablation (20~80 years old)
• Echocardiographically measured left atrial size < 55mm
• Anticoagulation eligible patients

Exclusion Criteria:

• AF associated with significant cardiac anomaly, structural heart disease affecting hemodynamics
• Ineligible to CT imaging due to significant renal disease
• Prior history of AF catheter ablation or cardiac surgery
• Active internal bleeding
• Anticoagulation ineligible patients
• Valvular AF
• Life expectancy < 1year
• Drug or alcohol addicted patients
• Other unacceptable patients for clinical trial determined by investigators