Bachmann bundle impairment following linear ablation of left anterior
wall: impact on left atrial function
Background: We aimed to evaluate the effect of Bachmann bundle (BB)
impairment on electrical and mechanical function of the left atrium
(LA), as well as the long-term clinical impact of such impairment.
Design: We measured activation time in the five LA walls in 56 patients
with atrial fibrillation. LA reservoir, conduit, and contractile
function were also evaluated. Patients were divided into two groups
based on ablation strategy: the circumferential pulmonary vein isolation
(CPVI) group and CPVI with anterior wall linear ablation (LAWA) group.
Patients in the CPVI+LAWA group were divided into two sub-groups based
on ECG differences following ablation: the BB impairment group and
intact BB group. LA activation time and function were then compared
between the ablation strategy groups and the CPVI+LAWA subgroups.
Results: Patients in the CPVI+LAWA group exhibited longer activation
times in the anterior and lateral walls of the LA, poorer LA synchrony,
and reduced LA contractile and reservoir function when compared with
those in the CPVI group. In the BB impairment subgroup, we observed a
discrepancy between electrical/mechanical remodeling. Among five walls,
activation time was longest in this region. BB impairment was also
associated with reduced LA function. Conclusion: Significant changes in
LA function and conductibility were observed in patients with anterior
wall ablation, especially those with iatrogenic BB impairment.