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End-of-service management of leadless cardiac pacemakers: a case report.

Case report A 90-year-old man had been implanted with a leadless pacemaker (Micra MC1VR01 transcatheter pacing system, Medtronic, Minneapolis, MN, USA) for a complete atrioventricular block in 2016. He had severe comorbidities with a history of myocardial infarction with coronary artery bypass graft surgery, permanent atrial fibrillation, severe chronic kidney disease, and thrombocytopenia necessitating hy droxyurea chemotherapy. Baseline transthoracic echocardiography showed a preserved left ventricular systolic function with moderate aortic stenosis, mild mitral regurgitation, and severe tricuspid regurgitation. At implantation, ventricular pacing threshold was 0.63 V at a 0.24 ms pulse width, with an expected battery longevity>10 years. At 3-month follow-up, device interrogation showed an elevated pacing threshold >3 V, with normal R-wave sensing and impedance measurement. Chest radiography showed no significant dislodgement. Considering patient’s comorbidities, it was decided not to extract nor reposition the device. The pacing threshold remained>3 V during follow-up with an end-of-service expected to occur in 2018. In July 2018, a second leadless pacemaker implantation procedure under local anaesthesia was then decided. The second leadless device (Micra MC1VR01 transcatheter pacing system, Medtronic, Minneapolis, MN, USA) was easily placed higher on the septum, displaying excellent electrical parameters at the first positioning (pacing threshold 0.63 V, ventricular sensing 8 mV, and impedance 630 X). Procedure total