Development of a third generation intraventricular impedance imaging (III) system: evaluation of hardware design

Intraventricular Impedance Imaging (III) applies an innovative technique for estimation of cardiac catheter position. It is based on electrical impedance measurements and uses a multi-electrode probe mounted at a tip of a cardiac catheter. After analyzing the previous versions of the III system, a new system hardware realization was proposed, built, and tested. The signal acquisition module is based on AD7850-a highly integrated electronic component. A special protocol was developed for optimal high speed communication between the 32 channel III system and the IBM PC controller. This protocol also significantly reduces the required electronic component count. The results obtained by the prototype evaluation showed that: the proposed realization is working according to expectations, the signal generation provides sufficiently accurate signals, and the system requires 3 ms to generate a set of data-sufficient for real-time 60 Hz determination of catheter position and instantaneous ventricular volume.