Implantation of a permanent pacemaker following orthotopic heart transplantation: a systematic review and meta-analysis.

Abstract

Background: Orthotopic heart transplant (OHT) is among the final armamentariums for end-stage heart disease. Many patients who have had OHT require a post-transplant permanent pacemaker (PPM) implantation due to an abnormal conduction system. We aimed to evaluate the risk of mortality and acute rejection in patients with OHT who had received PPM compared to patients without PPM and to determine predictors for PPM placement in this population.

Methods: We comprehensively searched for studies from MEDLINE, EMBASE, and Cochrane databases from inception to September 2023. Inclusion criteria focused on patients who had undergone OHT and PPM implantation post-transplant. Data from each study were combined using a random-effects model. Results were expressed as relative risk (RR) or odd ratios (OR) with a 95% confidence interval (CI).

Results: A total of 9 studies were included in this meta-analysis incorporating a total of 54,848 patients (3.3% had PPM). The pooled all-cause mortality rate among patients with PPM post-OHT was 26% (95% CI: 19-33%, I² = 1%). There were no differences between post-heart transplant patients with PPM and those without PPM in risk of all-cause mortality (RR 0.76, 95% CI: 0.43-1.34; I² = 45%) and acute rejection (RR 1.22, 95% CI: 0.74-2.00, I² = 59%). Bi-atrial anastomosis was associated with an increased risk of PPM implantation post-OHT (OR 7.74, 95% CI: 3.55-16.91, I² = 0%), while pre-OHT mechanical circulatory support (MCS) was associated with a decreased risk of PPM implantation post-OHT (OR 0.45, 95% CI 0.27-0.76, I² = 0%).

Conclusion: There were no significant differences in all-cause mortality or acute rejection between post-OHT recipients who required PPM compared to those who did not receive PPM. Further, bi-atrial anastomosis portended the need for PPM implantation, while MCS was associated with a decreased occurrence of PPM.