Background: Pulmonary vein reconnection has been described as a frequent cause for atrial fibrillation recurrence after ablation. Contact force catheters have been recently developed and radiofrequency delivery with over 10gr of force related to improved outcomes. Also, recent technology value pressure and radiofrequency power to determine a better lesion. The aim of our study was to compare the pulmonary vein reconnection rate after pulmonary vein isolation with magnetic navigation (contact force under 5 gr and high catheter stability) with manual catheter (higher pressure, lower stability).
Methods and results: Two groups were compared, 124 consecutive patients submitted to atrial fibrillation re-ablation with magnetic navigation (14.0% of 885 patients) and 125 consecutive patients submitted to re-ablation with manual navigation catheter (14.4% of a series of 868 patients). Pulmonary vein reconnection rates were analyzed and the more common veins to recur were described. At least one pulmonary vein was reconnected in 116 procedures (93.6%) of the magnetic group versus 114 (91.2%) in manual navigation group. The number of reconnected veins on the different groups were (magnetic vs manual respectively) four veins in 40 procedures (32.3%) vs 52 (41.6%), three veins n 29 procedures (23.4%) vs 11 (8.9%), two in 30 procedures (24.2%) vs 37 (29.6%) and one in 17 procedures (13.7%) vs 14 (11.2%) (p=NS). In the manual group, the first procedure was performed with contact force catheter in 21 procedures (16.8%). During re-ablation, in the manual group, the number of reconnected veins was not different whether the first procedure was performed with contact force catheter or not (at least one reconnected vein in 90.5% of the procedures and four reconnected veins in 52.6%). In both groups (magnetic and manual) the commonest reconnected vein was the right superior (75.8% vs 72.8%) followed by the right inferior (65.3% vs 71.2%). The left superior vein was reconnected in 61.3% vs 58.3% of the procedures and the left inferior in 59.7% vs 60.8% (p=NS).
Conclusions: The majority of patients submitted to atrial fibrillation re-ablation had more than one reconnected vein. We did not observe a significant difference whether first ablation was performed with magnetic navigation (lower pressure and high stability) or manual navigation catheters and thus a higher pressure during radiofrequency delivery did not correlate with lower prevalence of reconnected veins. Long term efficacy of the radiofrequency lesion depends on an equation with many variables and new algorithms should also include catheter stability.