Interaction of work electromagnetic field with implanted cardiostimulation system, analysis by in vitro method at patient practicing of profession

摘要

The aim was to assess the clinical significance of the interaction of the cardiac implantable electronic device (CIED) of the selected patient and the interfering electromagnetic field (EMF) during practicing of a profession in an industrial environment. The next step was to analyze risk factors using the specific measurement on the phantom and to determine the conditions for minimizing the risk. We present a method of the provocative analysis on the phantom of the stimulation system. The phantom approximates the system in patient's chest. The measurement was performed using real-time analysis of sensed signals and the pacemaker (PCM) response on the programmer to the source of an electromagnetic interference (EMI) at the workplace. Disturbing signals from an external source can cause an emergency operation of PCM, like asynchronous pacing or pacing inhibition. The interaction was assessed in various exposures, changes of device programming and function responses to EMI. The magnetic field was detected in close proximity (< 5 cm) of CIED from the surface of the EMI source. Induced potentials were continuously sensed at close distances from the source and it activated asynchronous stimulation. The response varied according to the system orientation. At greater distances (< 20 cm above, < 10 cm in front) the intermittent signal sensing and the pacing inhibition occurred during standard PCM programming. Zones for safe operation were determined and the PCM programming was optimized. The interference signal sensing is significantly affected by the CIED programming. This patient can continue to practice the profession safely with high probability by following certain precautions and adjusting PCM settings. We present this analysis on the phantom of the CIED as one of options where the measurement does not pose a risk to the patient with an implant.