Making the difference
Kuroki et al have elegantly investigated if an improved semi-automated
VGLA system could ameliorate the efficiency of this technology compared
to manual manipulation of the catheter. They have clearly demonstrated
in experimental setting that the mean lesion counts were significantly
reduced by using the SA as opposed to MN (5.3±5.9 vs 33.7±10.0, P=0.007)
. This proves an improved efficiency of SA over the MN approach.
Moreover, the lesion counts resulted favorable also in comparison with
RF ablation (28.0±4.4, P=0.019). The catheter use time resulted shorter
for SA as compared to MN in both acute and chronic study (28.0±12.1 to
12.7±15.0 and 28.8±3.8 to 11.5±12.7 min). Of course this represents an
important advantage for the efficiency of the approach and it might
constitute the basis for obtaining a similar outcome even in the
clinical setting. What I would consider quite a fundamental result is
that the SA mode is the homogenous circumferentiality of the lesion and
the transmurality demonstrated both in acute and chronic studies. This
suggests that the uninterrupted movement provided by the SA with
continuous energy application could promote an improved transmurality
over the MN and also with less propensity to create gaps. The gross
anatomy well shows the difference between the two modalities of laser
ablation and support the value of the SA as the preferred mode of deploy
laser energy.
The advantage of directly viewing the tissue is also revealed by the
comparison between laser and RF application, being the level of RF
application deeper in the vein. Therefore, one might conclude that SA
laser modality of ablation ensures a higher level of proximal PV’s
ostium lesion continuity, transmurality and less gap formation. The dose
of 13 and 15 W in the current clinically available SA VGLA (5) seems
adequate to promote effective lesions even in humans (6-8). The
improvement of the VGLA system portraying the novel SA modality can be
rightly considered an effective, efficient approach for achieving a high
rate of PVI. We all know there are several new technologies and tools
reaching the EP field, each of them aiming at successful and durable
PVI. We need to applaude Kuroki and co-workers, since their effort was
to show the consistency and the value of VGLA energy applied through a
novel SA technique.
Needless to remind us that other initiatives are taking place in the EP
field, led by researchers and companies as to identify the most
successful ablative approach for PVI. Laser therapy is an attractive
technology belonging to the family of balloon-based platforms and plays
a crucial role in achieving this goal. Reasonably, comparative studies
will be required to establish the relative merit to each proposed
ablative treatment strategy