Utilizing Leadless Pacemakers in Extremely Elderly Patients With a Conventional Pacemaker System: A Two-Year Follow-Up Case Series Without Generator Extraction in High-Risk Scenarios

Background and objectives Leadless pacemakers, known for their safer clinical profile, offer significant advantages for elderly patients at a higher risk of complications associated with transvenous pacemaker procedures, particularly those susceptible to high-risk bleeding and infections related to cardiac implantable electronic device interventions. This study explores an alternative use of leadless pacemakers without removing existing transvenous systems, deviating from conventional generator replacement and lead re-interventions. Methods This study was conducted with full approval from the Institutional Review Board, Medical Ethical Committee, Centro Hospitalar Conde São Januário, Macau. Between January 2018 and December 2021, we conducted a retrospective case series involving extremely elderly individuals (aged 85 years or older) at a high risk of complications, necessitating either generator replacement or lead re-implantation. The study considered implanting a leadless pacemaker (Micra; Medtronic, Minneapolis, MN, USA) without removing the transvenous generator. For the primary endpoints, we evaluated procedure-related complications and clinical outcomes during hospitalization. Secondary endpoints included the stability of parameters and any unexpected interference or interactions between the two systems during the two-year follow-up. Results Eleven patients (aged 86-101) were enrolled, most receiving antiplatelet or anticoagulation therapy. Leadless pacemaker implantation proceeded without major complications or adverse clinical outcomes during hospitalization. Regular follow-up was conducted every three to six months for adjusting pacemaker parameters and interrogating each patient. Over two years, three patients died from non-cardiac causes: two from infection and one from spontaneous intracranial hemorrhage, while eight completed regular follow-ups. We didn't detect any episodes of ventricular arrhythmias or intracardiac capture from the transvenous pacemaker system. We observed the stability in both the longevity and the voltage of the conventional generator battery, maintaining similar parameters without significant depletion (mean voltage decline: -0.07V/year). Parameters of the leadless pacemaker remained consistently normal without interference with existing pacing systems. Conclusion Implanting leadless pacemakers without removing transvenous pacemaker generators appears safe and effective for extremely elderly patients who are at high risk