The Biological Significance of Radio-Frequency Radiation Emission on Cardiac Pacemaker Performance

Environmental assessment for the satellite power system concept development and evaluation program-electromagnetic systems compatibility

“…Pacemakers are more'iikely to fail in low frequency pulsed rf fields as opposed to cw fields. ·Data taken by Mitchell and Hurt (1975) indicate that the average failure threshold decreased from 117 V/m at a pulse width of 10 ~s, to 33.8 V/m at 1 ms and to 18.6 V/m at 20 ms, when the PRF and frequency were constant. Denny et al (1977) found that failures are more likely to occur if the rf source is pulsed at a rate of 10 PPS or less.…”

“…For example Mitchell and Hurt (1975) found that the average threshold increased from less than 50 V/m at 450 MHz to nearly 600 V/m at 3200 MHz even when the pulse rate and width of the test source were maintained constant ( Figure 40). This observation is qualitatively supported by some earlier work ( Figure 40) of Bonney et al (1973), which shows that the potentially hazardous field intensity level increases from about 75 V/m at 915 MHz to 250 V/m at 2810 MHz.…”

Biological Effects and Health Implications of Radiofrequency Radiation

“…The amplifier increases the level of its input signal, usually in several stages, and may modify, select, or analyze the signal at some stage. Studies by Mitchell and Hurt (1976) indicate that EMI is strongly dependent on frequency, pulse width, pulse repetition rate, E-field level and polarization.…”

“…The reasonable, prudent, and feasible solution has been to introduce adequate EMI protection into future pacemakers. Studies by Mitchell and Hurt (1976) found that protective shielding is a major factor in preventing or reducing interference.…”

“…In the past few years, the manufacturers have made remarkable progress in eliminating the potential EMI problem. At present, essentiallyall current state-of-technology pacemakers will meet or exceed the EMI threshold level of 200 V Im (Mitchell and Hurt, 1976).…”