Electromagnetic Interference and Cardiac Implantable Electronic Devices: Is the Ride in Electric Cars Still Cool?

New-generation electronic appliances and cardiac implantable electronic devices: a systematic literature review of mechanisms and in vivo studies

INTRODUCTION

Cardiac implantable electronic device (CIED) functions are susceptible to electromagnetic interference (EMI) from electromagnetic fields (EMF). Data on EMI risks from new-generation electronic appliances (EA) are limited.

OBJECTIVE

We performed a systematic literature review on the mechanisms of EMI, current evidence, and recently published trials evaluating the effect of EMF on CIEDs from electric vehicles (EV), smartphone, and smartwatch technology and summarize its safety data.

METHODS

Electronic databases, including PubMed and EMBASE, were searched for in vivo studies evaluating EMF strength and incidence between CIEDs and commercial EVs, new-generation smartphones, and new-generation smartwatches.

RESULTS

A total of ten studies (three on EVs, five on smartphones, one on smartphones, one on smartphones and smartwatches) were included in our systematic review. There was no report of EMI incidence associated with EVs or smartwatches. Magnet-containing smartphones (iPhone 12) can cause EMI when placed directly over CIEDs - thereby triggering the magnet mode; otherwise, no report of EMI was observed with other positions or smartphone models.

CONCLUSION

Current evidence suggests CIED recipients are safe from general interaction with EVs/HEVs, smartphones, and smartwatches. Strictly, results may only be applied to commercial brands or models tested in the published studies. There is limited data on EMI risk from EVs wireless charging and smartphones with MagSafe technology.

Electromagnetic interference from automobile passive keyless entry in cardiovascular implantable electronic devices

INTRODUCTION

The automobile passive keyless entry (PKE) system is a potential source of electromagnetic interference (EMI). We aim to determine the incidence and significance of EMI from automobile PKE system in cardiovascular implantable electronic device (CIED) patients.

METHODS

This was a single-center cross-sectional study conducted at Maharaj Nakorn Chiang Mai hospital, Thailand. Patients with CIED were instructed to lock and unlock two automobiles using the PKE system. Any EMI or arrhythmias were detected by CIED interrogation and single-lead electrocardiogram event recorder. We also used a spectrum analyzer to identify the automobiles working frequency bandwidth.

RESULTS

There was a total of 102 CIED patients. Device types included 48.0% defibrillators, 37.3% permanent pacemakers, and 14.7% cardiac resynchronization therapy device. Both interrogated data from device and event monitor revealed no incidence of EMI during the PKE activation. We failed to identify the working frequency bandwidth of the two studied cars due to very low signal strength, thus blended in with the background noise.

CONCLUSIONS

Automobile PKE systems transmitted very low power signals. Therefore, under normal circumstances, CIED patients can use automobile PKE system safely without any EMI regardless of key fob positions in relation to the CIED pulse generator.

TRIAL REGISTRATION

The study was registered at ClinicalTrials.gov (https://clinicaltrials.gov), and the identification number is NCT03016390.

[Electromagnetic interference : Pacemakers, cardiac resynchronization therapy devices, implantable cardioverter-defibrillator]

Patients with cardiac pacemakers, implantable cardioverter-defibrillators (ICDs), and cardiac resynchronization therapy devices (CRT) are exposed to different types of electromagnetic interference (EMI) at home and at work. Due to the constantly increasing role of electrically active appliances in daily use and the introduction of new therapy concepts such as the leadless cardiac pacemaker and the subcutaneous defibrillator, this topic is of great relevance. The further development of the implanted devices and the almost complete use of bipolar leads has reduced the overall risk of EMI. This review article provides information about the current status of possible interference in the private environment and how to avoid it. In addition, information is provided on how to deal with occupational sources of interference.

An in vitro Evaluation of the Effect of Transient Electromagnetic Fields on Pacemakers and Clinical Mitigation Measures

Background: The effect of transient electromagnetic fields on the function of pacemakers is not well-evaluated. There is a lack of effective methods for clinicians to reduce electromagnetic susceptibility (EMS) during implantation of pacemakers. This study aimed to evaluate whether a novel method of handling the excess leads in the pocket can lower the EMS of pacemakers and consequently reduce the effect of electromagnetic interference caused by transient electromagnetic fields on pacemakers.

Methods: An in vitro chest model was established to simulate the clinical condition of dual-chamber pacemaker implantation. Three different intertwining patterns of excess leads were examined: parallel, twisted once, and multiple twisted-pair. Oscillated currents were injected into a copper electrical wire set horizontally above the model to create a radiated magnetic field to simulate the transient daily electromagnetic exposure of pacemakers. The electromagnetic induction of current was measured. The occurrence of EMS-related adverse events was evaluated when the induced pulsed voltage was applied.

Results: Transient electromagnetic fields can induce electromagnetic noise in the pacing loop and inhibit the release of pacing pulses. The multiple twisted-pair intertwining pattern of excess leads was associated with a lower induced voltage amplitude than both the parallel and once-twisted patterns (P < 0.001). Even once twisted could significantly reduce induced voltage amplitude compared to not twisted (P < 0.001). A lower incidence of pacing inhibition was also observed in the multiple twisted-pair group than in the other two groups (P < 0.001).

Conclusions: Transient electromagnetic fields can cause pacing inhibition. Twisting the excess leads for multiple turns in the pocket is an effective method to reduce the EMS of the dual-chamber pacemaker.