We conduct a randomized study comparing the safety and effectiveness of two interventional ablation techniques for treatment of paroxysmal atrial fibrillation: the segmental pulmonary vein ablation approach, (1) with empiric isolation of all pulmonary veins or (2) Segmental Isolation of the arrhythmogenic pulmonary vein(s)

BACKGROUND Atrial fibrillation ablation procedures typically involve isolation of all pulmonary veins (PVs), yet the need for such an extensive ablation strategy in all patients is unclear.

OBJECTIVE:

We conduct a randomized study comparing the safety and effectiveness of two interventional ablation techniques for treatment of paroxysmal atrial fibrillation: the segmental pulmonary vein ablation approach, (1) with empiric isolation of all pulmonary veins or (2) Segmental Isolation of only the arrhythmogenic pulmonary vein(s). The single-blind interventional, randomized study will include 106 patients in each arm.

A reablation procedure, with the use of the same technique as the first ablation, will be offered to the patient in case of a symptomatic atrial fibrillation recurrence beyond the third month after the ablation procedure.

Follow-Up After discharge, patients w ill be scheduled for repeated visits in the arrhythmia clinic at 3 and 6 months after the first ablation. At each of these visits, intensive questioning for arrhythmia-related symptoms (fatigue, dizziness, and nausea) since the last follow-up visit was performed, especially for those that the patient had experienced before ablation. At every follow-up visit, 7-day Holter monitoring w ill be performed. Multislice CT or MRI of the pulmonary vein w ill be obtained before and 3 months after the ablation procedure for evaluation of the pulmonary vein anatomy and for detection of radiofrequency ablation-induced pulmonary vein stenosis .

Study End Points and Definitions The primary end point of the study will be freedom from atrial tachyarrhythmias (of > 30-second duration) including atrial fibrillation and atypical atrial flutter documented by 7-day Holter monitoring performed at the 6-month follow-up. Two secondary study end points will be chosen. The first will be freedom from arrhythmia-related symptoms during the 6-month follow-up. Because early recurrences of atrial tachyarrhythmias within the first month after ablation may be a transient phenomenon, this time interval was excluded from analysis. Second, a composite of periprocedural pericardial tamponade, thromboembolic complications, and pulmonary vein stenosis with > 50% lumen loss (main vessel or first branching) was defined as a safety end point

Inclusion Criteria:

• patients between 18 and 80 years old with paroxysmal atrial fibrillation
• Episodes with a maximum duration for 7 days
• at least 4 episodes / month
• at least one attempt with Class I or III anti-arrhythmic drugs and/or with ß-blockers without success
• sufficient oral anticoagulation for a minimum of four weeks previous to ablation

Exclusion Criteria:

• hyperthyroidism
• mitral regurgitation > II°
• intracardiac thrombi documented by transesophageal echocardiography
• left ventricular ejection< fraction 35%,
• history of ablation, myocardial infarction or cardiac surgery in the previous 3 months
• history of left-atrial ablation procedure
• contraindication for oral anticoagulation