Abstract

We hypothesized that pulmonary vein (PV) orientation influences tissue contact of the contact force (CF) sensing radiofrequency ablation catheter (CFC) and therefore atrial fibrillation (AF) free survival after pulmonary vein isolation (PVI). The aim of this study was to determine the association between PV orientation, CF and AF free survival in patients undergoing CFC PVI. Sixty consecutive patients undergoing CFC PVI were included. ECG-triggered cardiac CT scans were obtained in all patients before PVI, and the PV orientation was measured at the insertion in the LA for all PVs in both the transverse and frontal plane. PVs were assigned to 1 of 4 orientation groups: ventral–caudal, dorsal–caudal, ventral–cranial and dorsal–cranial. Mean age was 59 years, 88% had paroxysmal AF. AF free survival off anti-arrhythmic drugs after a median follow-up of 12 months was 58% after a single PVI procedure. No association was found between PV orientation and CF. Furthermore, no association was found between PV orientation and AF free survival. In univariate analysis, the number of lesions with a mean CF of 10 g was associated with AF free survival. However, in multivariate analysis, only the AF duration was significantly associated with AF free survival. This study shows that in patients undergoing PVI with the CFC ablation system, PV orientation does not affect CF and is not associated with AF free survival. PV orientation assessment does not appear to be necessary in patients undergoing CFC PVI.

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.