Leadless cardiac pacemaker in elderly patients: How old for a new technology?

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Leadless transcatheter pacemakers are considered as a safe and effective option for cardiac pacing in patients (pts) at higher risk of complications with conventional transvenous cardiac pacing. Purpose Our aim was to assess the clinical "real-life" feasibility and outcomes of leadless pacing in elderly pts in a high-volume center over a mid-term follow-up (FU) period. Methods Elderly pts (aged ≥ 75 years) who underwent leadless MICRA® system pacemaker implantation with a FU period above 3 months were included in this retrospective monocentric study. Results 130 pts were included (84 ± 5.6 years old, male 66.2%). Indications were: Atrioventricular block (permanent 15.4%; transient 27.7%), atrial fibrillation bradycardia 50% and sinus node dysfunction 6.9%. Leadless system pacing was preferred over conventional pacing in pts with: transvenous pacemaker extractions due to infectious 18.5% or vascular 1.5% complications; active systemic infection and urgent need for cardiac stimulation 20%; complex conventional vascular approach 21.6%; severe tricuspid valve disease 1.5%; deterioration of general condition and clinical frailty 22.3%; shortly after transvalvular aortic valve replacement 8.5%. Among the pts, 6.2% had previous leadless Nanostim® device implantation with dysfunction of the system. Pts had either local anesthesia 13.2% or deep sedation 86.8%. The average fluoroscopy time was 4.3±2.9 minutes and number of device deployments before the final position ranged from 1 to 7 with a mean value of 1.5±1 positions. Pacing threshold during implant was 0.5±0.4 V at 0.24ms, only 4 pts (3%) had an implant threshold of >1.0 V at 0.24 ms. Two postoperative deaths were observed: 1 cardiac arrest related to myocardial dysfunction and consequent pulmonary edema in a patient with advanced heart failure, and 1 death secondary to myocardial perforation with need for surgical repair that occurred among the first implantations with an apical device position and a patient with multiple comorbidities. The total rate of major complications was 2.3% with only 1 vascular complication at the femoral puncture site. The median time from the leadless pacemaker implant procedure to discharge was 5±6.5 days (minimum 1 and maximum 40 days): 55.6% pts were able to leave the cardiology department within the first 72 hours. The mean FU period was 17 months ± 15 months with a mortality rate of 12.3% (cardiovascular impairment 5.4%; non cardiovascular-related deaths 6.9%). Increase in pacing thresholds was noted in 4 pts with subsequent stabilization; 92.2% of pts presented with thresholds lower than 1V at 0.24 ms. All pts remained free of infections during FU with no cases of device dislodgement observed. Conclusion Elderly pts are at higher risk of complications; our experience confirms their clinical frailty and underlines the favorable safety profile of leadless system pacing with a low rate of complications and stable pacing thresholds.