Protocol for ICE/IVUS imaging of the PVs
As part of the trial, ultrasound imaging of the junctions between LA and
pulmonary veins (PVs) was performed with either ICE or IVUS as per
operator’s discretion.
For ICE imaging, a 9F catheter with a 9 MHz rotational transducer
providing a maximal radial depth of 50 mm (Ultra ICE, Boston Scientific)
was used. For IVUS imaging, a 20 MHz digital probe with maximum
ultrasonic detection depth of 24 mm (Visions PV .018, Volcano, San
Diego, CA) was chosen and used mounted on a guidewire (0.014-in
percutaneous transluminal coronary angioplasty guidewire) as per
manufacture instructions.
The ultrasound-imaging probe was introduced into the LA via the
trans-septal access and advanced under fluoroscopic guidance distally
into each pulmonary vein (PV) with the aid of a long steerable sheath.
Images were recorded during slow manual pullback of the probe from each
vein into the LA body. Each PV was imaged twice, before and after
ablation.