In vitro tests reveal sample radiofrequency identification readers inducing clinically significant electromagnetic interference to implantable pacemakers and implantable cardioverter-defibrillators.

BACKGROUND: The use of radiofrequency identification (RFID) systems is expanding and highlights the need to address electromagnetic interference (EMI) to implantable pacemakers and implantable cardioverter-defibrillators (ICDs). OBJECTIVE: This study sought to examine the electromagnetic compatibility (EMC) between RFID readers and implantable pacemakers or ICDs. METHODS: During in vitro testing, 15 implantable pacemakers and 15 ICDs were exposed to 13 passive RFID readers in 3 frequency bands: 134 kHz (low frequency [LF]), 13.56 MHz (high frequency [HF]), and 915 MHz (ultra high frequency [UHF]). RESULTS: While being exposed to LF RFID, a reaction was observed for 67% of all pacemaker tests (maximum distance 60 cm) and 47% of all ICD tests (maximum distance 40 cm). During HF RFID exposure, a reaction was observed for 6% of all pacemaker tests (maximum distance 22.5 cm) and 1% of all ICD tests (maximum distance 7.5 cm). For both pacemakers and ICDs, no reactions were observed during exposure to UHF RFID or continuous-wave RFID. Pacemakers and ICDs were most susceptible to modulated LF RFID readers. CONCLUSION: Although there is in vitro testing evidence for concern for implantable pacemaker and ICD EMI at LF and HF, the FDA has not received any incident reports of pacemaker or ICD EMI caused by any RFID system. We do not believe the current situation reveals an urgent public health risk.

Advances in ambulatory monitoring: regulatory considerations.

Conventional ambulatory electrocardiogram (ECG) (Holter) monitoring involves 2 or 3 surface leads recorded with electrode positions and signal characteristics that are different from diagnostic quality 12-lead ECGs due to the limitations imposed by technology on the ambulatory recorders. The rapid pace of technological development for medical devices, particularly electrocardiography, has now enabled the recording of diagnostic quality 12-lead ECG waveforms for extended time periods. This capability allows Holter recording to become another source for diagnostic 12-lead ECG records on a par with other modalities such as resting ECG and exercise stress testing. Additionally, other diagnostic techniques such as S-T segment analysis and Q-T interval analysis that rely on diagnostic quality waveforms can now be applied. All of these enhancements to the traditional Holter modality have altered the regulatory perspective of these devices, since the enhancements may represent a new intended use for the device.