Cardiac pacemakers in electric and magnetic fields of 400-kV power lines.

BACKGROUND

The cardiac pacemaker (PM) implantation rate per million is high. Earlier studies have found interference to PMs by electromagnetic fields. The aim of the study is to investigate disturbances in cardiac PM using a human-shaped phantom in electric and magnetic fields of 400-kV power lines.

METHODS

The phantom was used in the following manner: isolated from the ground, grounded from left or right foot, or grounded from left or right hand.

RESULTS

Out of the tested PMs one had such a disturbance that it set the pace 60 times per minute, when the electric field was 6.7-7.5 kV/m and the magnetic field was 2.4-2.9 μT. The electrode configuration of the PM was unipolar. In bipolar configuration, the same PM had no disturbance. During the test period, other PMs only had minor disturbances or none at all. Some PMs do not record time information for minor disturbances. In such cases, it was impossible to link the disturbances to the exposure under the power line.

CONCLUSIONS

The electric field under a 400-kV power line may disturb a PM. However, only one type out of several tested PMs showed a major disturbance and that was only with a unipolar electrode configuration. The risk of disturbances is therefore not deemed to be high.