The Impact of Leadless
Pacemaker on the Development of Pacemaker induced Cardiomyopathy and
Tricuspid Regurgitation, A Retrospective
Analysis Authors:
David Kerling MD, Adam Kisling MD, Andrew Heroy, Thomas Arnold, Mark
Haigney MD, Matthew Needleman MD FHRS 11All research
participates are affiliated with Walter Reed National Military Medical
Center and this is the location of where the research was conductedAbstract
Introduction:Leadless pacemakers (LPs) have been suggested to have a lower incidence
of pacemaker induced cardiomyopathy (PICM) compared with transvenous
systems. LPs have also been suggested to cause less frequent and less
severe tricuspid valve regurgitation (TVR) when compared to traditional
transvenous pacemakers (TVPs). Given limited research in this field, our
study aims to better understand the incidence of PICM and TVR in
patients with a LP and the factors that affect these incidences.Methods:The study comprised of patients within the National Capital Region
Military Health System who received a Medtronic Micra LP from 2017 to
2021 and had a pacing percentage of >20%. Pre-procedural
and follow-up echocardiograms were retrospectively assessed to determine
the change in left ventricular ejection fraction (LVEF) and the degree
of TVR. Given the known impact of the PICM definition on the reported
incidence, we assessed rates of PICM using two distinct definitions,
1.) ≥10% decrease in LVEF or 2.)
≥10% decrease in LVEF to an LVEF of <50%. We also assessed
the pacemaker implantation location and the change in QRS duration after
implantation and pacing.Results:The study included a total of 48 patients. The average age of patients
in the study was 77, with 67% males. The most common reason for LP
implantation was complete AV block (38%). Pacemaker locations included
high (13%), mid (31%), and apical septum (56%). The mean time
interval between pacemaker implantation and follow up echocardiogram was
697 days (SD 460). A total of 5 patients (12.5%) met definition 1 for
PICM and 3 patients (6.25%) met definition 2. TVR was graded to be more
severe than baseline in 37% of patients, unchanged in 32%, and
improved in 30%. The average change in QRS duration after pacing was an
increase of 46ms with an average QRS duration of 159ms at
follow-up.Conclusion:Compared to commonly reported incidences of PICM, LPs appear to have a
significantly lower rate of PICM, regardless of the PICM definition
used, increase in QRS duration, or implantation location. In this study,
LPs did not statistically significantly impact TVR
severity.Keywords: Leadless Pacemaker,
Pacemaker Induced Cardiomyopathy, Tricuspid Valve Regurgitation