Impact of an LCPV in balloon based PVI procedures
There have been several prior reports on a CB guided PVI in patients of
an LCPV. In the past, CB was considered technically challenging to
achieve a PVI in patients with an LCPV, because the balloon size and
lack of an appropriate balloon compliance made the complete occlusion of
the PVs difficult. A previous study showed that atrial tachyarrhythmias
were apt to recur after the ablation procedure using the first and
second generation CBs5,11,12). A point by point RF
energy application may be suitable for the isolation of an LCPV, because
it can isolate the PV at the LCPV ostium regardless of the size, length,
or configuration of the LCPV. However, prior studies comparing the
2nd generation CB and RF in patients with an LCPV
reported no significant difference in the atrial tachyarrhythmia
recurrence13,14). Moreover, a recent randomized clinical
trial (CIRCA‐DOSE study) revealed the presence of an LCPV was associated
with a trend towards higher rates of atrial tachyarrhythmia recurrence
following the PVI15). In this study, no significant
difference in the atrial tachyarrhythmia recurrence was observed in the
patients with an LCPV randomized to those undergoing a CB ablation and
those undergoing an RF ablation15).
On the other hand, Nakamura et al. investigated the efficacy and
long-term outcome of a Hot-balloon guided PVI16). Of the
patients in this study with an LCPV diameter of < 34 mm, 75%
of the LCPVs were isolated at the ostium and 25% needed an individual
isolation of the superior and inferior branches16).
Nakamura et al. revealed that the presence of an LCPV was not associated
with recurrent AF, and significantly fewer Hot-balloon applications were
sufficient for accomplishing the PVI16).
An LCPV is generally defined as having a length of 5 mm or more from the
PV ostium to the bifurcation point (a short common trunk is 5-15mm and a
long common trunk more than 15mm6,7), but we defined the
LCPV length between the PV ostium and bifurcation point as longer than
15mm on the MDCT findings. In the present study, a short LCPV was found
in 21 patients. Since each short LCPV could not be isolated at the
ostium, the superior and inferior branches of the LCPV had to be
isolated individually. Therefore, those short LCPV cases were excluded
from the present study analysis. There was no difference with regard to
the total procedure time, ablation time for accomplishing the PVI, and
atrial tachyarrhythmia recurrence between the patients with a short LCPV
and those without an LCPV.
To the best of our knowledge, the present study was the first report to
evaluate the efficacy of a VGLA guided PVI for an LCPV. The LB is so
compliant that it can be inflated to any pressure and size change, which
enables a maximum balloon/tissue contact regardless of the size or shape
of each PV ostium. In the present study, we achieved a successful
electrical isolation at the LCPV ostium in the majority of the patients
with an LCPV. In addition, a comparable clinical result of atrial
tachyarrhythmia recurrence could be observed in our study between the
patients with and without an LCPV. Moreover, the ablation procedure time
was shorter in the patients with an LCPV because the superior and
inferior branches were isolated simultaneously with the VGLA as a
result, which presumably attributed to a shorter catheter manipulation
time. Although an electrical isolation at the LCPV ostium is difficult
in cases with a large LCPV, VGLA could be selected as the first-line
therapy in terms of the acute success and long-term clinical outcome.