The ventricular fibrillation waveform approach to direct postshock chest compressions in a swine model of VF arrest.

Background: In retrospective swine and human investigations of ventricular fibrillation (VF) cardiac arrest, the amplitude-spectral area (AMSA), determined from the VF waveform, can predict defibrillation and a return of spontaneous circulation (ROSC).

Objectives: We hypothesized that an algorithm using AMSA in real time to direct postshock chest compression (CC) duration would shorten the time to ROSC and improve neurological outcome in a swine model of VF cardiac arrest with acute myocardial infarction (AMI) or nonischemic myocardium.

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

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.

Emergent percutaneous coronary intervention for resuscitated victims of out-of-hospital cardiac arrest.

Long-term survival rates even after successful resuscitation from out-of-hospital cardiac arrest are dismal. Most of those initially resuscitated expired during their hospitalization. Recent reports have suggested that a more aggressive approach to postresuscitation care is the key to better outcome.

The influence of myocardial substrate on ventricular fibrillation waveform: a swine model of acute and postmyocardial infarction.

Objective: In cardiac arrest resulting from ventricular fibrillation, the ventricular fibrillation waveform may be a clue to its duration and predict the likelihood of shock success. However, ventricular fibrillation occurs in different myocardial substrates such as ischemia, heart failure, and structurally normal hearts. We hypothesized that ventricular fibrillation is altered by myocardial infarction and varies from the acute to postmyocardial infarction periods.

Direction of signal recording affects waveform characteristics of ventricular fibrillation in humans undergoing defibrillation testing during ICD implantation.

Introduction: In cardiac arrest due to prolonged ventricular fibrillation (VF), defibrillation is more likely to result in a perfusing rhythm if chest compressions are performed first. Furthermore, the VF waveform can predict the shockability of VF and thus automated external defibrillators (AEDs) are being designed to analyze the VF waveform to direct therapies. However, it is unknown whether the VF waveform is dependent on recording direction, which could be altered by incorrect placement of AED patches.