The purpose of this study is to compare the efficacy and safety of PV isolation with continued antiarrhythmic drug treatment (PVI+ADT) to PV isolation without continued ADT (PVI-ADT) in patients undergoing treatment for symptomatic recurrent AF.

Subjects that underwent PV isolation for paroxysmal or non-longstanding persistent AF and are free of arrhythmia at the end of the 3-month blanking period while taking ADT. Eligible subjects who sign the study informed consent form will be randomized into one of two study arms:

PVI+ADT Group: continue ADT through 9 months follow-up PVI-ADT Group: no ADT through 9 months follow up

Inclusion Criteria:

• patient has continued (IC or III) ADT throughout the 3-month blanking
• patient is free of symptomatic and asymptomatic AF (as evidenced by 1-day Holter) at the 3-month visit
• drug-resistant (at least one class IC or III) symptomatic AF was the primary indication for prior PV isolation
• in the three months prior to PVI, at least one episode of symptomatic or asymptomatic AF
• PV isolation was performed according to the standards set forward by the Task Force Document (sedation or general anesthesia)
• PV isolation was the only target for ablation (except for cavotricuspid (CTI) ablation if documented AFL)
• PV isolation was performed by point-by-point irrigated radio frequency (RF) guided by contact-force (Biosense) (10-30gr-continuous lesion)
• PV isolation (i.e. entry block) was verified in each vein after a waiting time and adenosine (with continued RF if acute reconnection)
• Signed Patient Informed Consent Form.
• Age 18 years or older.
• Able and willing to comply with all follow-up testing and requirements.

Exclusion Criteria:

• Longstanding persistent atrial fibrillation (>12 months of continuous AF)
• Previous ablation for AF
• left atrium (LA) size > 55 mm
• left ventricular ejection fraction (LVEF) < 40%
• AF secondary to electrolyte imbalance, thyroid disease, or reversible or non-cardiac cause
• coronary artery bypass graft (CABG) procedure within the last six months
• Awaiting cardiac transplantation or other cardiac surgery
• Documented left atrial thrombus on imaging
• Diagnosed atrial myxoma
• Women who are pregnant (by history of menstrual period or pregnancy test if the history is considered unreliable) or breastfeeding
• Acute illness or active systemic infection or sepsis
• Unstable angina
• Uncontrolled heart failure
• Myocardial infarction within the previous two (2) months
• History of blood clotting or bleeding abnormalities
• Contraindication to anticoagulation therapy (ie, heparin or warfarin)
• Life expectancy less than 12 months
• Enrollment in any other study evaluating another device or drug
• Presence of intramural thrombus, tumor or other abnormality that precludes catheter introduction
• Patients not taking any class IC or III ADT at 3 months after PV isolation
• No documentation of entry block at initial PV isolation - no waiting time or adenosine.
• Additional linear ablation or defractionation during the initial procedure (except for CTI ablation for documented or induced cavo-tricuspid isthmus dependent flutter).