Potential role of frequency-domain representation in selection of optimal defibrillatory shock

Many electrical waveforms have been investigated for their efficacy at achieving ventricular defibrillation. In all of these studies to date, parameters of the waveforms have been expressed in the time-domain, usually current versus time. These studies have resulted in improved shocks for both transthoracic and internal defibrillation. However, such studies have failed to yield an understanding of why some electrical waveforms are superior to others (e.g., biphasic waveforms are generally superior to uniphasic waveforms at equal delivered energies). In this study, electrical waveforms are transformed into the frequency domain, and analyzed for possible insight into the mechanism of defibrillation