John Triedman Laboratory, Children's Hospital

Implantable Cardiac Defibrillators (ICDs) save the lives of patients with unstable heart rhythms and 100,000 patients receive these devices per year in the US.  Their use in children is less frequent and less standardized than in adults so that determining efficient electrode placement is challenging and uncertain. We are collaborating with J. Triedman, M.D. at Children's Hospital Boston and M. Jolley, M.D. at Stanford University  to develop interactive finite element (FEM) computational models to test electrode locations for their effectiveness in defibrillation in children. The models come from CT or MRI scans segmented into tissue types and then meshed for FEM.  The system also includes a library of realistically shaped ICD case and wire electrodes and an interactive interface allows the user to easily place and move the electrodes in the model to evaluate different implantation locations.  To date we have fully segmented three CT scans, from 2, 10, and 27 year-old subjects, and have created a database of approximately 100 suitable electrode locations per model, which we are testing for bioelectric field strength and homogeneity.  Initial findings have included evaluating the effectiveness of standard locations in adults and novel locations in children.