Electronic Article Surveillance: A Possible Danger for Pacemaker Patients

Abstract

In order to evaluate if antitheft devices commonly designed as electronic article surveillance (EAS) systems can be dangerous for pacemaker patients, in vitro and in vivo studies were made in close cooperation between a pacemaker center and an EAS designer. Three types of EAS radiation including radiofrequency, magnetic, and pulsed electromagnetic fields were applied to various pacemakers. The in vitro study consisted of exposing to the EAS fields 28 pacemakers connected to unipolar leads. Radiofrequency fields and pulsed electromagnetic fields evoked minor effects and no prolonged inhibitions. When exposed to magnetic fields, most of the pacemakers switched to "fixed rate" pacing, but inhibitions were observed in 13 pacemakers exposed to 300 Hz, and in 14 pacemakers exposed to a 10-kHz magnetic field when they were moved at cardiac frequencies within the fields. The in vivo study was made on 32 volunteers treated by 26 different pacemakers: 22 single chamber and ten dual chamber. All patients had been monitored in the pacemaker clinic and pacemakers were working well. Radiofrequency and pulsed electromagnetic fields did not affect the pacemaker function. Magnetic interference evoked prolonged inhibition of seven out of the ten dual chamber pacemakers, causing brief asystole in patients being continually paced. None of the dual chamber pacemakers incorporated "safety stimulation intervals" after ventricular blanking. The EAS artifact was sensed after the ventricular blanking causing a cross-talk ECG pattern. No reprogramming was induced by the electromagnetic fields. This experience demonstrates that certain EAS may be dangerous for pacemaker patients. Following this cooperative study a pacemaker safe EAS circuit delivering short bursts of magnetic fields has been designed.

The interference threshold of unipolar cardiac pacemakers in extremely low frequency magnetic fields

“…Some of the studies do not mention the magnitude of the magnetic induction emitted by the investigated EAS system [7]. Others give only maximum values without specifying their location or their spatial distribution [8,11]. Lucas et al [9] performed experimental studies with different EAS systems where they also simulated the induction loop stretched by the CPM system.…”

“…As this estimation of the induction loop was too high, Beaugeard et al could have estimated the potential danger for CPM patients in the vicinity of EAS systems to be higher than it is. Dodinot et al [8] performed their experimental studies with a 570 cm 2 loop. Besides the partly different cardiac pacemaker models in the experimental simulation and the in vivo studies this is a possible explanation for the results in the in vitro and the in vivo experiments differing from each other.…”

Implants médicaux et champs électromagnétiques basses fréquences 0–100 kHz

“…Très tôt, des études portant sur les interférences entre les portiques antivol et les PM ont été menées notamment in vivo (Dodinot et al, 1993 ;Lucas et al, 1994). Les appareils sont le plus souvent composés de bobines générant un champ magnétique dont la fréquence de fonctionnement peut aller de quelques centaines de Hz à 2,45 GHz pour des champs dont l'amplitude et la forme sont également très variées (modulés, pulsés...).…”

The effects of mobile phones on pacemaker function

“…The effects of the electromagnetic field created by various systems on medical devices and pacemakers are well recognized [1][2][3]. Mobile phones are being used at an increasing pace worldwide, thereby bringing the adverse effects of the electromagnetic field to a level of public health problem [4][5][6][7][8].…”