Incidence of Pacing-Induced Cardiomyopathy Among Patients With Leadless Versus Transvenous Ventricular Pacemakers.

Background: Frequent nonphysiological ventricular pacing and resultant pacing-induced cardiomyopathy are well characterized in transvenous pacemakers (TVP). The incidence of pacing-induced cardiomyopathy in leadless pacemakers (LP) is less understood, particularly compared with TVP.

Methods: We utilized the TriNetX Analytics Network database to identify 2594 propensity score-matched patients who underwent implantation of LP and TVP between January 1, 2016, and January 1, 2023. The primary outcome was the incidence of pacing-induced cardiomyopathy, defined as a new diagnosis of systolic heart failure or a left ventricular ejection fraction <50%, occurring from the index hospitalization through December 2024, after excluding other etiologies of heart failure.

Results: The median age of the study population was 73.8 years (±15). Baseline left ventricular ejection fraction was similar between groups (LP: 63±7 versus TVP: 64±8). During a median follow-up period of 2.4 years, 422 incident cases of PCM occurred. Incidence rates of pacing-induced cardiomyopathy were comparable (LP: 7.6% versus TVP: 8.6%; P=0.187), including in patients with pacing indications of complete heart block or atrioventricular nodal ablation (LP: 10.3% versus TVP: 10.4%; P=0.948). The mean drop in left ventricular ejection fraction was comparable between both groups; however, patients with LP were less likely to undergo cardiac resynchronization therapy upgrade compared with those with TVP (LP: 9.7% versus TVP: 17.5%; P=0.014).

Conclusions: The incidence and characteristics of pacing-induced cardiomyopathy are similar between LP and TVP. However, patients with LP are less likely to undergo cardiac resynchronization therapy upgrade.