title: Periodic pacemaker spike attenuation with preservation of capture: an unusual electrocardiographic manifestation of partial pacing electrode fracture.
abstract: This report describes the electrocardiograms of a patient with an intermittent electrode fracture presenting with periodic attenuation of the pacemaker spike without loss of ventricular capture. There was infrequent prolongation of the spike-to-spike interval probably because the pulse generator interpreted random false signals as interference and reverted to its fixed-rate mode. These observations add to the spectrum of electrocardiographic abnormalities of electrode malfunction.
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography; D004566:Electrodes; D005260:Female; D006327:Heart Block / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D010138:Pacemaker, Artificial / Q000009:adverse effects*