Catheter Ablation
The appropriate ablation site was determined based on anatomical length,
catheter stability, tissue thickness and nearby vulnerable structures.
In most cases, this represented the narrowest bridge of conducting
tissue between scars or anatomical obstacles or the site of the reentry
circuit exhibiting low-voltage fractionated potentials (FPs) occurring
in the diastolic phase in relation to the activation of the surrounding
myocardium. RF energy was delivered using an irrigated 3.5-mm-tip
ablation catheter (Thermocool® ST catheter, Biosense Webster), with a
power of 25-45 W and a cutoff temperature of 45°C. The endpoint of the
procedure was defined as termination of all AT forms and their
noninducibility with incremental and programmed atrial pacing. If a new
AT was induced either during ablation or during reinduction, it was
targeted for ablation using the same strategy as detailed above.