Eight year Follow-Up Data on a Leadless Pacing System Real life experience in comparison to data of the prospective trial

Abstract Introduction The Micra leadless intracardiac pacing system has been introduced and implemented into clinical routine in 2015, with its next generation MICRA AV in 2020. Feasibility, implantation safety, and acute success have been proven in the setting of controlled studies. Even apart from controlled studies, this new technology was beneficial for the individual patient. We aimed to report our single center follow-up (FU) data with a follow-up of up to six years. Methods In 292 patients (146 men; age: 81±5,7 y), Micra implantation was performed. Pacemaker interrogation was performed one to seven days after implantation and during FU (1; 3; 6, then every 6 month) up to 84 months. Data were assessed in a real-life setting and compared with existing data of a controlled prospective trial. Results The implantation was successful in all 292 attempts with only one pericardial effusion as major complication. During follow up there were two patients developing severe heart failure symptoms resulting in an implantation of a CRT-device and switching of the leadless pacemaker system. The average acute thresholds, sensing and impedance after system release were: 0.57±[email protected]; 10,02±3,96mV and 752±1201Ohm. During follow up of up to 8 years neither, pacemaker failure, nor infections were reported. Measurements were reevaluated for long-term thresholds, sensing and impedance: 0.75 ± 0.38V @ 0.24 ms; 18,38 ±2,75 mV and 525 ± 102 Ohm. During eight years, no significant changes from acute to long-term measurements were detectable. In comparison to the controlled trial, our measurements of this real-life cohort were very similar. Conclusion In a real-life setting, the implantation of the leadless Micra system demonstrates a high rate of implantation success without major complications. We were also able to show stable long-term system parameters in the clinical setting of up to seven years of follow up with a very good battery longevity of about 12,3 years.