The heart defibrillation device (1) has an implantable cardiac pacemaker combined with a defibrillator (3). A defibrillation electrode and a back plate electrode (4) is provided with an implantable stimulation and sensing electrode (5). The defibrillation electrode is separated from the stimulation electrode into a functional position. The defibrillation electrode has a flexible coil made of metal or biocompatible steel.