Heart Transplantation Requiring Permanent Pacemaker: Risk Factors and Outcomes

Background/Objectives: Following heart transplantation (HT), a subset of patients will require an early or late permanent pacemaker (PPM). We explored risk factors and outcomes associated with PPM implantation in this population. Methods: Using the United Network for Organ Sharing (UNOS) database, we identified all adult patients undergoing HT from 2013 to 2023 who received a PPM early (prior to discharge) or late (>6 months post transplant). Propensity score matching (PSM) was used for control cohorts was. Primary outcomes included recipient survival at 30 days and 1 and 5 years. Predictors of early and late PPM, as well as post-PPM mortality, were assessed using Cox and logistic regression models. Kaplan-Meier survival curves were compared using a log-rank test. Results: Following PSM, the early PPM cohort included 354 patients, and the late PPM cohort included 554 patients. Early PPM patients showed similar 30-day and 1- and 5-year survival (p = 0.582, 0.421, and 0.2844 respectively) but lower rates of graft failure (1.1% vs. 4%, p = 0.017) and primary graft dysfunction (PGD) (1.7% vs. 4.2%, p = 0.046). Late PPM patients had reduced survival at 30 days and 1 year but not at 5 years (p < 0.001, p = 0.0023, 0.050 respectively). Neither early nor late PPM was independently associated with increased risk of mortality after HT. Donation after Circulatory Death (DCD) organs were associated with a lower risk of early PPM (aOR = 0.409, p = 0.020). Late PPM patients showed higher rates of PGD (2.5% vs. 0.5%, p = 0.007). Conclusions: Early or late PPM is not an independent risk factor for mortality after HT, but differing short-term morbidity and mortality are observed.