Utilization Of Leadless Pacemaker During Index Hospitalization Following Orthotopic Heart Transplantation For Complete Heart Block

Introduction Conduction abnormalities are infrequent but known immediate and delayed complications post heart transplant. Temporary pacing is required in the immediate postoperative period, with escalation to permanent pacing if conduction remains unresolved. Permanent pacemaker (PPM) implantation is associated with device- and surgical-related complications. Many of these complications can be avoided with the less invasive implantation of leadless PPMs and have been reported previously in several cases status post heart transplant. However, these reports were related to conduction abnormalities arising > 1-year after transplant. Here we present the first case of leadless PPM implant after heart transplant in the biopsy dense immediate postoperative period where additional benefits exist. Case Report The patient is a 67-year-old male with a past medical history significant for nonischemic cardiomyopathy diagnosed in 2012. He underwent an orthotopic heart transplant on 2/11/2022 as UNOS status 2. On 2/14, there was a loss of capture of the patient's epicardial pacing wires, and the patient experienced two episodes of asystole. He was successfully resuscitated with a return of spontaneous circulation via surgical placement of two new epicardial wires, and his pacer was set to dual-chamber antibradycardia pacing. He was maintained on isoproterenol until being switched to theophylline on 2/16. The patient continued to be in heart block and underwent placement of leadless Medtronic Micra permanent pacemaker on 3/3/2022 (Figure 1) with no complications to date. Summary An estimated 2-24% of patients will require placement of a PPM for conduction abnormalities following heart transplantation. PPM use in this post-transplant population requires careful consideration given the immunocompromised status of these patients with the highest risk of mortality being within 30 days of transplant. Complications of PPM implant include infection, hematoma, risk of tricuspid regurgitation, and potential for lead dislodgement during imperative surveillance endomyocardial biopsies under fluoroscopic guidance. Leadless pacemakers are implanted using minimally invasive catheterization which reduces the risk of these complications and confers a shorter recovery time. This case provides evidence for the feasibility, efficacy, and advantage of leadless PPM use in the immediate postoperative period after heart transplantation.