Analysis of amplitude spectral area and slope to predict defibrillation in out of hospital cardiac arrest due to ventricular fibrillation (VF) according to VF type: recurrent versus shock-resistant.

Background: In out-of-hospital cardiac arrest (OHCA) due to ventricular fibrillation (VF), VF may recur during resuscitation (recurrent VF) or fail to defibrillate (shock-resistant VF). While retrospective studies have suggested that amplitude spectral area (AMSA) and slope predict defibrillation, it is unknown whether the predictive power is influenced by VF type. We hypothesized that in witnessed OHCA with initial rhythm of VF that the utility for AMSA and slope to predict defibrillation would differ between shock-resistant and recurrent VF.

Predictors of resuscitation outcome in a swine model of VF cardiac arrest: A comparison of VF duration, presence of acute myocardial infarction and VF waveform.

Introduction: Factors that affect resuscitation to a perfusing rhythm (ROSC) following ventricular fibrillation (VF) include untreated VF duration, acute myocardial infarction (AMI), and possibly factors reflected in the VF waveform. We hypothesized that resuscitation of VF to ROSC within 3min is predicted by the VF waveform, independent of untreated VF duration or presence of acute MI.

Methods: AMI was induced by the occlusion of the left anterior descending coronary artery.