Abstract 15706: Response to Adenosine After Pulmonary Veins Isolation with an Open Irrigated Catheter at Different Power Settings: Results from a Randomized Prospective Study
Introduction: Catheter ablation is a valid therapeutic option for the treatment of drug-refractory atrial fibrillation (AF). Several studies have shown that the main reason for procedural failure is the absence of durable lesions leading to pulmonary vein reconnection. In this prospective randomized study we sought to compare the acute response to adenosine and the long term outcome after pulmonary vein isolation utilizing an open irrigated ablation catheter with different power settings.
Methods: In this prospective randomized study 144 patients undergoing ablation for paroxysmal AF were included. All patients underwent pulmonary vein antrum isolation and ablation of the posterior wall contained within the pulmonary veins. All patients underwent the procedure with an open irrigated ablation catheter and under general anesthesia. Patients were randomized to PV isolation up to 30Watts (Group 1, n=72) vs PV isolation up to 40 Watts (Group 2, n=72). After PV isolation was achieved, all patients underwent challenge test with 24 mg of adenosine to check for PV reconnection. In case of reconnection effort was taken to complete the isolation of the PVs in all patients.
Results: Baseline characteristic had no statistical significant difference in between groups. In group 1, a total of 280 PVs were isolated while in group 2 a total of 282 PVs were isolated. After adenosine test, 108 PVs (38%) reconnected in group 1, while 18 PVs (6%) reconnected in group 2 (p< 0.0001). After adenosine, all patients underwent PVs re-isolation of the reconnected veins by using the same power described at the time of randomization. At 14± 2 months follow up, 26 pts in group 1 (36%) and 13 pts in group 2 (18%) had recurrence of atrial arrhythmias (p< 0.001). All patients experiencing recurrences underwent a second procedure. At the redo procedure, 20 pts of group 1 (77%) vs 2 patients of group 2 (15%) had PV reconnection (p< 0.001).
Conclusions: This prospective randomized study shows that in the absence of an objective indicator of contact, a power of 40 watts is associated with a lower acute reconnection with adenosine challenge and with better success at follow up.
- © 2012 by American Heart Association, Inc.