Dynamic differences between ventricular fibrillation types induced in human patients by different types of stimulation

Reports the results of a study on the differences observed in ventricular fibrillation (VF) induced in human patients by means of T-shock (TS) and 50 Hz stimulation during implantable cardioverter defibrillator (ICD) placement. The objective of the study was to find out which one of the two types of stimulation induces VF closer to spontaneously occurring VF episodes. The dynamical arrhythmia characterization is done by analyzing the phase portrait and estimating the correlation dimension from the VF tracings. The authors´ preliminary results indicate that T-shock stimulation may induce VF condition whose dynamic is more similar to the one observed with spontaneous VF. An important aspect of the investigation is that the dependence of VF properties on the induction method may give an insight into the dynamic underlying VF initiation and thus may be helpful for the study of sudden cardiac death