Durability of EIVM-created atrial lesions
This study investigated the long-term effect of EIVM by comparative EAM
before, immediately after and at the time of repeated CA for recurrent
AT. The nature of the myocardial lesions created by EIVM are distinct
from those created by RF owing to their intrinsically different
mechanisms. RF lesions, created by external thermal energy, have a
variable degree of sustainability, which depends on energy delivery
parameters, contact force and atrial tissue
characteristics.17 In contrast, retrograde ethanol
delivery creates a chemical lesion related to ethanol penetration in the
myocardium, with venous drainage depending on the VOM, including a
variable extent of the LA posterior wall and MI.2 In
dogs, EIVM creates an acute and dense pale patch, visible from the
endocardium, which suggests transmural damage and transmyocardial
ethanol flow.2 In humans, several studies have
consistently shown EIVM creating a low-voltage lesion in the VOM region,
although to a variable extent.4–6,18,9,14,15,12However, no study has evaluated the sustainability of EIVM over time.
Here, by demonstrating EIVM-created lesion durability in all consecutive
patients referred for repeated CA after EIVM, we closed a knowledge gap
regarding EIVM lesion characteristics.