Measurement of Defibrillator Surface Potentials for Simulation Verification

Despite the growing use of implantable cardioverter defibrillators (ICDs) in adults and children, there has been little progress in optimizing device and electrode placement. To facilitate effective placement of ICDs, especially in pediatric cases, we have developed a predictive model that evaluates the efficacy of a delivered shock. Most recently, we have also developed an experimental validation approach based on measurements from clinical cases. The approach involves obtaining body surface potential maps of ICD discharges during implantation surgery and comparing these measured potentials with simulated surface potentials to determine simulation accuracy. Comparison of the simulated and measured potentials yielded very similar patterns and a typical correlation greater than 0.9, suggesting that the predictive simulation generates realistic potential values. Ongoing sensitivity studies will determine the robustness of the results and pave the way for use of this approach for assisting optimization of ICD use.