Implantable intravascular defibrillator: evaluation of defibrillation waveforms with inferior vena cava electrode system.

Background: A percutaneously placed, totally intravascular defibrillator has been developed that shocks via a right ventricular (RV) single-coil and titanium electrodes in the superior vena cava (SVC) and the inferior vena cava (IVC). This study evaluated the defibrillation threshold (DFT) with this electrode configuration to determine the effect of different biphasic waveform tilts and second-phase durations as well as the contribution of the IVC electrode.

Methods: Eight Bluetick hounds (wt = 30-40 kg) were anesthetized and the RV coil (first-phase anode) was placed in the RV apex.