Abstract: A defibrillation system including a high voltage metallized plastic film capacitor which is charged to a high voltage and is discharged to the body of the patient by way of a paddle. The defibrillation system includes a charge abnormality detection circuit for detecting dielectronic breakdown of the capacitor, a notifier for notifying the operator of the system of detection of charge abnormality in response to the detection signal produced by the detection circuit, and a switch circuit for inhibiting the feeding of high voltage to the capacitor in a high voltage generating cirucit, in response to a detection signal. Other aspects of the present invention include a metallized plastic film capacitor construction including a plurality of capacitor elements each of which is formed from wound-up metallized plastic films and to which metallic contacts and capacitor terminals are provided along with external resistances, as to reduce the production of loud noise during dielectric breakdown, in particular.