INTRODUCTION
Atrial fibrillation (AF)-related functional tricuspid regurgitation
(FTR) has been recognized. In AF patients without left heart disease,
the prevalence of moderate or severe FTR ranges from 15% to
33.6%[1, 2]. The worsening FTR is associated with
more symptoms such as edema, fatigue, exercise intolerance and adverse
cardiovascular events[3]. Survival is
significantly shorter in patients with moderate or severe FTR, even
after adjustment for coexisting conditions[4].
Despite evidence suggesting atrial reverse remodeling and FTR reduction
after restoring sinus rhythm[5], a considerable
proportion of AF patients developed persistent AF[6,
7], and the FTR progresses over time.
Although the majority of persistent AF patients often manifest a fast
heart rate[8], some of them manifest a slow heart
rate and are indicated for pacemaker[9]. Irregular
rhythm and slow heart rate may contribute to FTR in these
patients[10]. As the previous study demonstrated
the tricuspid regurgitation (TR) deterioration following a
pacemaker[11], the coexistence of AF and a
pacemaker may accelerate the FTR deterioration. Right ventricular pacing
has shown FTR deterioration in AF patients with bradycardia even in the
absence of lead[12, 13], and the main mechanism
was considered to be pacing-induced ventricular
dyssynchrony[14]. Left bundle branch area pacing
(LBBAP) is a physiological pacing method with excellent electrical and
mechanical synchrony[15], but the data about FTR
in patients with bradycardia responding to LBBAP is rare. The purpose of
this study was to explore the change of FTR after LBBAP implantation in
patients with persistent AF and bradycardia.