An optically-coupled logger for the measure of RF-induced voltage on pacemakers and ICDs

Pacemakers and implantable cardioverter defibrillator are active implantable medical devices (AIMD) composed by an electrical unit (generator) and electrical connections to the heart (lead). They are designed and manufactured to have a degree of immunity that reduces the risk of electromagnetic interference (EMI) for most sources of electromagnetic fields (EMF). The aim of the study is to present a logger for the measurements of voltage induced at the pacemakers/implantable defibrillators input stage when exposed to EMF. The logger can be used to assess the role of the lead configuration and path in determining the EMI for signals in a frequency range between 300 MHz and 3 GHz. Its design and characterization are here presented. Preliminary measurements show that the lead path actually play a role on the induced voltage intensity, in particular at lower frequencies, whereas lead configuration has a minor impact. Future measurements campaigns are necessary to further investigate this aspect.