title: An unusual complication of a myocardial electrode--apatite mantle on the platinum-iridium spurs.
abstract: A case of a high excitation threshold that occurred 2 years 5 months after the initial implantation of pacemaker electrodes is described in a girl 4 years 3 months of age. This complication was considered to be due to calcification of the platinum-iridium electrode spurs. The calcified material was shown to be a kind of apatite using the X-ray powder diffraction method. This complication is rare, but it must be kept in mind since battery longevity has markedly improved in recent years.
mesh_terms: D001031:Apatites; D001145:Arrhythmias, Cardiac / Q000209:etiology; D002675:Child, Preschool; D004562:Electrocardiography; D004567:Electrodes, Implanted; D005260:Female; D006801:Humans; D007495:Iridium; D010138:Pacemaker, Artificial / Q000009:adverse effects*; D010984:Platinum
chemical_list: D001031:Apatites; D007495:Iridium; D010984:Platinum