Rapid switching between transverse electrode pairs within a biphasic shock lowers implantable defibrillator thresholds

In order to minimize energy requirements and prolong the lifetime of implantable cardioverter-defibrillators (ICD´s), it is necessary to optimize the delivered waveform without compromising defibrillation efficacy. Four electrodes were implanted on, in, and near the heart of nine pigs, Results indicate that by rapidly switching between sequential electrode pairs within each phase of a single biphasic shock 2, 4, or 8 times, significantly lower energies are needed for defibrillation