A medical device for electrical termination of an arrhythmic condition of a patients heart in embodiments of the invention may include one or more of the following features: (a) at least one battery (b) means for detection of an arrhythmic condition of a patients heart (c) at least one high voltage capacitor (d) converter means for providing charging current from said battery to said capacitor (e) means for maintenance of a charge on said capacitor between arrhythmia therapies (f) controller means responsive to detection of an arrhythmic condition of said patients heart and for providing a discharge control signal and (g) discharge circuit means for delivering voltage stored on said capacitor to said patients heart in response to said discharge control signal.
