PV isolation
After first-pass encircling PV antrum ablation, electrical conduction
between the left atrium and PV remained in 12 of 30 (40%) ipsilateral
PVs. Mapping using the mini-basket catheter identified 48 ablation
points through which the propagation wave entered the PV (ablation
points with a gap). At the remaining 742 ablation points, the
propagation wave was blocked along the PV isolation line (ablation
points without a gap). Additional ablation targeting ablation points
with a gap successfully eliminated conduction between the left atrium
and PV. In the end, PV isolation was achieved without complications in
any patients.
RFA was unexpectedly suspended at 84 of 790 (11%) ablation points due
to a rise in esophageal temperature (42 points), bradycardia (4 points),
or catheter dislodgement (38 points). RFA duration was significantly
shorter at points with unexpected suspension than those without (14 ± 5
vs. 28 ± 8 sec, p<0.0001). However, the presence of gaps was
comparable between the two groups (5% vs. 6%, p=0.51).