Electrophysiological testing in survivors of out-of-hospital ventricular fibrillation

One hundred ninety-six consecutive patients who survived out-of-hospital ventricular fibrillation and 46 controls were prospectively studied to determine whether programmed stimulation could reproduce the clinical arrhythmia. Sustained ventricular tachycardia or ventricular fibrillation was not induced in any of the controls. Multivariate analysis identified two independent predictors of induced sustained ventricular tachycardia: prior episodes of spontaneous sustained ventricular tachycardia and previous myocardial infarction. Ventricular fibrillation was induced only in those survivors of out-of-hospital ventricular fibrillation who had not had prior spontaneous sustained tachycardia. This indicates that prospective analysis of clinical variables can identify survivors of out-of-hospital ventricular fibrillation who have very high or very low probabilities that sustained ventricular tachycardia will be induced, and that there is a significant correlation between induced ventricular fibrillation and out-of-hospital ventricular fibrillation when the latter is the only clinical arrhythmia.