Abstract

Pulmonary vein isolation (PVI) for atrial fibrillation (AF) is performed with the endoscopically assisted laser balloon ablation system (EAS). We hypothesized that placement of a circular mapping catheter (CMC) in the pulmonary vein (PV) distal to the laser balloon during ablation is feasible and safe. Out of 58 included patients, 37 underwent mapping-guided EAS PVI, with the CMC inside the PV during laser ablation, and 21 patients underwent standard EAS PVI, with the CMC outside the PV during laser ablation. Mean age was 56 years and 81% had paroxysmal AF. In the mapping-guided ablation group, 91% of PVs were isolated with the CMC in the PV during EAS ablation, isolation was completed in 9% of PVs after the CMC was removed from the PV. After passing a learning curve in 18 patients, a significant drop in unsuccessfully isolated PVs was observed in the mapping guided EAS PVI group (15% to 4%, P = 0.020). No major complications were seen in the mapping-guided EAS PVI group. However, in the standard EAS PVI group, laser ablation was complicated by a temporary phrenic nerve palsy in 1 patient. After a median follow-up of 16.7 months, there was no statistical difference in AF free survival among treatment groups (mapping-guided: 56% vs. 52%, P = 0.875). Mapping guided EAS PVI with a distal CMC in the PV during laser ablation is feasible and seems safe as the standard EAS PVI approach.