Electromagnetic radiation (EMR) in the environment is a source of potential danger to a patient dependent on a cardiac pulse generator. We exposed a variety of demand pulse generators to a wide range of EMR. Reversion to "fixed rate" and occasionally complete cutoff was observed in several devices at power densities approximating those reported in one large metropolitan area. Practical techniques exist for producing pulse generators that are compatible with today's EMR environment, and steps must be taken by pulse generator manufacturers to reduce the sensitivity of their units.
Walter WH, Mitchell JC, Rustan PL, Frazer JW, Hurt WD. Cardiac Pulse Generators and Electromagnetic Interference. JAMA. 1973;224(12):1628-1631. doi:10.1001/jama.1973.03220260044009