| abstract |
An implantable defibrillator is described comprising means for detecting fibrillation, electrical generating means responsive to the detection of fibrillation for producing a biphasic waveform (33-35, 42-46) in which each phase is characterised by an impulse of predetermined polarty, magnitude and duration, in which the first phase is of greater duration than the second phase, and means for delivering the biphasic waveform to provide electrical shock to the ventricles of the heart. |