The purpose of this study is to determine whether catheter ablation is more effective than antiarrhythmic drugs in the early stages of paroxysmal atrial fibrillation. In all the patients a subcutaneous loop recorder will be implanted.

Inclusion Criteria:

• Age between 18 and 65
• At least three episodes of paroxysmal atrial fibrillation documented on an electrocardiogram or event recording during the last three years
• Never taken antiarrhythmic drugs or at most a pill in the pocket approach
• Willingness, ability and commitment to participate in baseline and follow-up evaluations

Exclusion Criteria:

• Paroxysmal AF for more than three years

• An episode of atrial fibrillation that lasted more than seven days within the past six months

• Persistent/permanent atrial fibrillation

• Atrial fibrillation from reversible cause (i.e. surgery, hyperthyroidism, pericarditis)

• Documented atrial flutter

• Structural heart disease of clinical significance including:

  • Cardiac surgery within six months of screening
  • Unstable symptoms of congestive heart failure (CHF) including NYHA Class III or IV CHF at screening and/or ejection fraction <30% as measured by echocardiography or catheterization
  • Unstable angina
  • Myocardial infarction within six months of screening
  • Surgically corrected atrial septal defect with a patch or closure device
  • LA size > 40mm

• Any prior ablation of the pulmonary veins

• Enrollment in any other ongoing protocol

• Untreatable allergy to contrast media

• Pregnancy

• Any contraindication to cardiac catheterization

• Prosthetic mitral heart valve

• Poor general health that, in the opinion of the Investigator, will not allow the patient to be a good study candidate (i.e. other disease processes, mental capacity, etc.)

• Contraindication to coumadin or heparin

• History of pulmonary embolus or stroke within one year of screening

• Acute pulmonary edema

• Atrial clot on TEE regardless of the patient's anticoagulation medication status