Three Tesla cardiac magnetic resonance imaging in a patient with a leadless cardiac pacemaker system

This is to the best of our knowledge the first report of cardiac magnetic resonance imaging (MRI) in a patient with a leadless cardiac pacemaker (LCP). Imaging was performed to rule out myocarditis in a 77-year-old male patient who had undergone LCP implantation (MicraTM, Medtronic) for atrial fibrillation with bradycardia 20 months before (Panel A). After a precise check of the functional parameters, the device was programmed to the MRI mode (V00 with a fixed rate of 80 b.p.m.). The MRI was performed in a long bore 3.0 Tesla magnet (Magnetom®Skyra, Siemens, Erlangen, Germany) with a maximal specific absorption rate of 1.5 W/kg. During MRI, the patient was monitored continuously by electrocardiogram and pulse oximetry. The cardiac MRI showed metallic artefacts at the apex of the heart due to the implanted LCP in the apex of the right ventricle and at the sternum due to sternal wires after cardiac surgery. The LCP caused an ‘arc-shaped’ artefact (in the cine images because of local field distortion leading to de-phasing of the transverse magnetization). However, these artefacts impaired the diagnostic quality of the cardiac MR images only in a small region of the apex (Panel s B, C , and D). During and after the scan, no device related adverse events occurred. The LCP’s functional parameters were stable (pacing threshold 0.5 V and 0.38 V, impedance 550 Ω and 580 Ω, sensing 20 mV and 20 mV before and immediately after the scan, respectively). Support by the Austrian Research Promotion Agency FFG, within the scope of project 853390 LaMiCellPro, is gratefully acknowledged. Supplementary material is available at European Heart Journal online.