<p>The stimulator (10) has a detector (2) for processing physiological signals received from the heart during charging a high voltage capacitor (5) and for determining a sequence of stimulation pulses generated after termination of anti-tachycardia therapy based on a predetermined criterion to existence or non-existence of tachycardia. The detector generates a tachycardia termination-signal if the physiological signals indicate the non-existence of tachycardia based on the criterion. A control unit (4) directly cancels the charging of the capacitor based upon the tachycardia termination-signal.</p>
