Behavior of Cardiac Pacemakers in Pulsed EM Fields

A presentation and an interpretation of the find­ ings of a series of seventeen investigative programs into the RF susceptibility properties of cardiac pace­ makers are given. Historical trends showing the rela­ tive effects of the manufacturers' design and construc­ tion improvements on the susceptibility properties are presented. A population profile of the pacemakers tested relates percentage of failures to field inten­ sity. Bar graphs illustrate the effects of PRF on pacemaker performance. Effects of different immersion media are examined.