Comparison of Two Pulmonary Vein Ablation Techniques for Persistent AF

Investigator Initiated Randomized Controlled Trial Comparing Two Radiofrequency Ablation Strategies in Patients With Persistent Atrial Fibrillation

Investigator initiated, randomized controlled trial of two radiofrequency (RF)ablation protocols currently performed in the electrophysiology lab, but have not been studied prospectively to identify which, if either technique, is superior for individuals with persistent atrial fibrillation (AF). Two-hundred subjects will be consecutively enrolled and randomized to either pulmonary vein isolation only or pulmonary vein isolation plus posterior left atrial wall isolation

Atrial fibrillation, the most common type of cardiac arrhythmia in clinical practice, affects approximately 2.7 million U.S. adults. Percutaneous catheter ablation is an effective treatment option for individuals with persistent AF. Pulmonary vein isolation (PVI) has emerged as the gold standard for paroxysmal AF with excellent success rates, however, individuals with persistent AF procedural efficacy from pulmonary vein isolation is not optimal. Therefore, improved ablation strategies for these individuals are needed. This randomized controlled trial will compare two radiofrequency ablation strategies, PVI alone and pulmonary vein isolation plus left posterior atrial wall (LPAW) isolation in individuals with persistent AF. Both strategies are currently used to treat persistent AF, but no randomized controlled trial ahs been conducted to investigate which strategy is more efficacious. Two-hundred subjects will be randomized into groups of 50 to undergo a radiofrequency ablation procedure for AF. For group 1, a series of radiofrequency applications will be delivered around both sets of pulmonary veins. For group 2, a series of radiofrequency applications will be delivered around both sets of pulmonary veins and along a roof and low posterior line of the left atrial wall. All subjects will be followed at 1 month, 3 months, 6 months, and 1 year post ablation. If indicated, antiarrhythmic drugs will be discontinued. For the first month, subjects will receive a continuously recording electrocardiogram heart card to monitor for AF, and then two-week ambulatory monitors at 3 months and one year post ablation.

A series of RF applications will be delivered around both sets of pulmonary veins with complete entry and exit block obtained around the antrums of all 4 pulmonary veins.

A series of RF applications will be delivered around both sets of pulmonary veins with complete entry and exit block obtained around the antrums of all 4 pulmonary veins. In addition, a roof and posterior line will be placed in the left atrium to achieve entrance and exit block on the posterior wall. Entry block will be confirmed by placing a circular mapping catheter in multiple locations along the posterior wall and confirming lack of presence of any local potentials. Exit block will be confirmed on the posterior wall with pacing at 10 amps from the ablation catheter at multiple locations within the box as well as all lines.

The primary hypotheses that PVI+PI will lead to a greater percentage of patients free from atrial arrhythmias after single ablation procedures than PVI alone.

Inclusion Criteria: Have symptomatic persistent AF (i.e., a sustained episode lasting more than 7 days). Refractory to at least one antiarrhythmic agent. Undergoing ablation for the first time. Exclusion Criteria: Paroxysmal AF Sustained atrial fibrillation lasting more than 3 years Left atrial diameter of 60 mm or greater