Design of a real-time ventricular fibrillation waveform analysis system for improved low energy DC defibrillation shock delivery

The authors´ earlier experiments have shown a relation between ventricular fibrillation (VF) voltage and defibrillation success. They proposed that a period of high absolute ventricular fibrillation voltage (AVFV) may be more susceptible to defibrillation. For the prospective study necessary to test this hypothesis, a PC based real-time system that analyzes VF waveform and synchronizes a defibrillation shock based on the VF analysis was developed. The new system has been used in three defibrillation protocols. The authors demonstrated effective detection of high AVFV periods (p<0.003) and an increase in defibrillation success ranging from 15-24% (p<0.04) with various lead configurations. As such, this system has been useful in increasing defibrillation success through improved delivery of low energy defibrillation shocks based on real-time VF waveform analysis.