Introduction
Transcatheter aortic valve replacement (TAVR) has been established as a
treatment of symptomatic aortic stenosis (AS) (1, 2 ), and its
benefit has been extended to low-surgical risk patients (3, 4 ).
Bicuspid aortic valve (BAV) is estimated to have a prevalence of around
0.5% (5 ) and 0.8% in the male population (6 ) and is
associated with the risk of developing aortic stenosis due to underlying
abnormal valve geometry and mechanical stress (7 ). Although AS
patients with BAV were excluded from early pivotal randomized studies
(1 - 4 ), the evidence concerning TAVR for BAV is important
because of the high prevalence of BAV among younger AS patients. Recent
studies have reported comparable prognosis, hemodynamic results, and the
safety of TAVR for BAV stenosis as compared to tricuspid aortic valve
(TAV) stenosis (8 - 10 ). In addition, a randomized study showed
the safety of TAVR for BAV in comparison with surgical aortic valve
replacement (SAVR) (11 ).
Conduction disturbance (CD) including new permanent pacemaker
implantation (PPI) and complete left bundle branch block (LBBB) have
been reported as major complications following TAVR, and they are also
associated with the risk of increased mortality and hospital
readmissions (12 - 14 ). To avoid TAVR-related CD, several
techniques such as double-cusp-view implantation with self-expandable
THV (15 ) and high implantation technique with
balloon-expandable THV (16 ) have been proposed. In addition,
membranous septum (MS) length represents an anatomic surrogate of the
distance between the aortic annulus and the bundle of HIS, and MS length
is inversely related to the risk of CD following TAVR (17 ).
Moreover, other studies reported, that both MS length and implantation
depth are associated with CD (18, 19 ). However, less is known
about the impact of the implantation depth and the MS length on CD
outcomes in bicuspid anatomy
This study aimed to investigate the impact of MS length and implantation
depth in predicting CD following TAVR with balloon-expandable valve in
patients with BAV.