Gerät und Verfahren zur Behandlung von Tachykardien mittels einer virtuellen Elektrode

An implantable device (10) and method for treating cardia arrhythmias in a patient's heart (11) are disclosed. A source of antitachycardia pacing therapy and an electrode system including at least three electrodes (80, 83, 86) for delivering the antitachycardia pacing therapy to the heart are provided. Circuitry and software (17, 19) for detecting a tachycardia having a site of focus in the heart and for determining the relative distances of the electrodes from the focus site are also provided. The three or more electrodes are connected to the source of antitachycardia pacing therapy based on the relative distances determined and in such a manner as to create a virtual electrode at the focus site upon delivery of the therapy to the heart.