Ablation protocol
As previously described,13, 14 encircling pulmonary
vein isolation was performed for patients registered in the AF Frontier
Ablation Registry who required it through the use of a radiofrequency
ablation catheter or cryoablation catheter, depending on the hospital’s
preference or type of catheter available at the time of the procedure.
The ablation procedure was guided by a circular mapping catheter or a
multiple-electrode catheter. The radiofrequency ablation employed an
irrigated-tip contact force-sensing catheter or an irrigated-tip
standard non-contact force-sensing catheter, and a 3-dimensional mapping
system (EnSite NavX/Velocity [St. Jude Medical, St. Paul, MN, USA],
CARTO [Biosense Webster, Irvine, CA, USA] or RHYTHMIA [Boston
Scientific, Marlborough, MA, USA]). Cryoablation was performed with an
Arctic Front Advance cardiac cryoablation catheter (Medtronic, Dublin,
Ireland), and any touch-up ablation was performed with a standard
irrigated-tip catheter. Some patients were injected intravenously with
adenosine triphosphate after pulmonary vein isolation to expose dormant
conduction between the pulmonary vein and left atrium. When acute
pulmonary vein reconnection or dormant conduction occurred, touch-up
ablation was performed. Additional linear ablation, such as tricuspid
valve isthmus linear ablation, mitral isthmus linear ablation, and left
atrial roof linear ablation, was performed at the physician’s
discretion. The residual potentials, including complex fractionated
atrial electrograms in the left atrium, were ablated as appropriate.