Analysis of ventricular arrhythmia episodes in patients at risk for ventricular fibrillation

Implantable cardioverter defibrillators (ICD) are usually implanted in patients with malignant ventricular tachyarrhytmias. Aim of this study was to investigate the recurrence of minor ventricular arrhythmias to predict the occurrence of ventricular fibrillation episodes in patients with ICD. The study design was a retrospective analysis of 237 patients, whose ICD was programmed to deliver electrical therapy only for ventricular fibrillation (VF) but not for ventricular tachycardia (VT). We calculated the number, the mean duration and the mean ventricular cycle of the non-sustained ventricular tachyarrhythmias (NST) and of the sustained ventricular tachyarrhythmias (ST). We found that VF patients had a significant higher incidence of ventricular tachycardia compared to the no-VF patients.In addition, the mean VT episodes duration was higher in patients of the VF group than in patients free from ventricular fibrillation and the ventricular cycle length resulted to be significantly shorter in VF patients.