Leadless pacemaker, right ventricular pacing burden, and heart failure

The optimal right ventricular pacing burden (%RVP) threshold associated with heart failure (HF) in patients with leadless pacemakers (LPs) remains unclear, whereas thresholds of 20% and 40% have been commonly used in studies of transvenous pacemakers.

The aim of this study was to assess the current %RVP cutoffs and explore how increased %RVP influences HF risk in LPs.

This registry-based observational study included patients who underwent LP implantation from 2015 to 2025. Patients with a prior HF diagnosis were excluded. %RVP was obtained through PaceMateLIVE, a vendor-neutral remote monitoring platform. The primary outcome was the first recorded HF diagnosis.

We included 3167 patients with single-chamber LPs. The mean age was 76 ± 13 years, and 45% were women. The median baseline %RVP was 71% (8%-98%). Over 2.4 years, the median absolute %RVP difference was 5.5% (0.7%-21.6%); 577 (18%) patients had the primary outcome. Patients with higher baseline %RVP at 20% and 40% cutoffs had increased risks of HF compared with those with lower %RVP (P < .05). A multivariable Cox model showed that time-varying %RVP was associated with a higher hazard of HF (per 10% increase, hazard ratio = 1.035 [1.013-1.059]).

Baseline %RVP thresholds of 20% and 40% may help identify patients with LPs who are at an increased risk of HF. However, the HF hazard increased progressively with an increasing %RVP. Given the lack of established upgrade pathways for current LP systems, careful patient selection and follow-up may be particularly important for patients expected to have a high pacing burden.