Assessment of LAPW and edophagus by ICE
Carto Soundstar® catheter was inserted into the LA
through the SL0 sheath. The ICE image by the catheter was created
digitally with the use of a VividTM iq imaging console
(GE Healthcare, Fairfield, Connecticut). The
Soundstar® catheter was rotated so that the imaging
plane could see the LAPW and esophagus (Figure 1A ). Gentle
clockwise torque was maintained to keep the catheter tip close to but
not contact to the posterior wall. The mean distance between the
transducer of the catheter and LAPW was 2.4 ± 0.9 cm (n=73). For imaging
from the LA, we used a 6 MHz frequency among variable frequencies (4.5,
6, 8, 10, and 11.5 MHz) equipped in Carto Soundstar®.
A special care was taken to obtain the image plane as perpendicular as
possible toward the LAPW. The esophagus in the ICE imaging was
characterized by two echolucent stripes of esophageal muscle separated
by a bright echogenic lumen (Figure 1B ). The images of LAPW and
esophagus were recorded at 4-6 pre-specified height levels including the
left superior pulmonary vein (LSPV), inter venous carina, left inferior
pulmonary vein (LIPV), and bottom of LIPV (Figure 1A ), while
referring a 3D LA CT image.