Electrical defibrillation outcome prediction by waveform analysis of ventricular fibrillation in cardiac arrest out of hospital patients.

OBJECTIVE: Indexes such as amplitude spectrum area (AMSA) and power spectrum area (PSA) obtained from electrocardiogram waveform analysis are possible predictors of outcome after electrical defibrillation for ventricular fibrillation (VF). In this study, we examined AMSA and PSA to determine whether these parameters can predict defibrillation outcome.

MATERIALS AND METHODS: A total of 83 out-of-hospital VF victims were classified into four groups according to type of cardiac rhythm after shock: return of spontaneous circulation (ROSC), VF, pulseless electrical activity (PEA), and asystole. AMSA and PSA were calculated from electrocardiograms prior to shock and compared between groups.

RESULTS: The mean AMSA (4.0-48 Hz) in the ROSC group was 24.2 ± 8.5 mV-Hz, which was significantly higher than that in the VF and asystole groups.

CONCLUSION: It is possible by analyzing the AMSA of VF to predict cases where electrical defibrillation is more likely to return cardiac rhythm. Furthermore, unnecessary electrical shocks with a low possibility of ROSC can be avoided, and chest compression should be continued to prevent myocardial damage and consequently improve prognosis.