We live in a world where in our daily life it has become almost impossible not to interact, either actively or passively, with various devices that are sources of electromagnetic fields and thereby a potential cause of electromagnetic interference (EMI). While this does not seem to cause problems for most people, there are various concerns for specific risk groups that can be affected adversely by these signals.

One of such groups is patients with cardiovascular implantable electronic devices (CIED) for treatment of arrhythmias as pacemakers (PM) and implantable cardioverter defibrillators (ICD). Furthermore, these devices tend to become more complex in their functions and required number of implanted components, as can be seen from increasing implant rates of cardiac resynchronization therapy pacemakers (CRT-P) and cardiac resynchronization therapy implantable cardioverter defibrillators (CRT-D). As an example, according to latest available data published by EUCOMED in 2014, in 2013 just in Europe there were in total 1260 patients per million of inhabitants who received such devices (PM, ICD, CRT-P, CRT-D). (1) One also has to bear in mind all those patients that have already had those devices implanted earlier, and have already been living with them for years.

In our daily work, we are often asked by our patients about ubiquitous objects which can serve as a relevant source of electromagnetic signals and should therefore be avoided. Specific concerns as voiced by our patients include (but are not limited to): personal devices, kitchen and household appliances, office and store appliances, entertainment devices, travelling and environment, and dental and medical tests and procedures. Unfortunately, professional scientific societies have still not been able to provide adequate guidelines in this issue.

Regarding the concerns of CIED patients, it has been shown that the function of these cardiac rhythm devices can be impaired by EMI, causing either temporary (environmental sources of EMI, resulting in temporary and reversible dysfunctions) or sometimes even permanent system malfunction (the risk is present, although low, with medical environment sources of EMI, such as magnetic resonance imaging). In worst cases, this could potentially lead to fatal events (for example EMI could cause oversensing in a PM device in a patient with asystole, leading to inhibition of pacing or causing inadequate ICD or CRT-D device shocks due to device’s misinterpretation of EMI as life threatening ventricular tachyarrhythmia – both resulting, in theory at least, in syncope and/or death).

So far, there have been studies on EMI affecting CIED from sources such as cellular phones, anti-theft devices, various remote controls, improperly wired/grounded appliances coming into contact with the body, MP3 players, induction ovens, and many other devices. (2-7) Furthermore, increasing global efforts to intensify security screening measures in the past decade have also brought into focus the use of metal detectors (which create a magnetic field that might interfere with the function of CIED); they are nowadays routinely used in many settings to detect ferrous and other dangerous items. (8, 9) It would also seem that the use of tablet computers can pose certain threats for those patients as well. (10) Another important group of sources of EMI is those which are encountered in workplace and/or industrial environments, such as high voltage power lines, transformers, welders, electric motors, and many others. Last, but not least, are those sources found in medical environments: magnetic resonance image scanners, electrosurgery, defibrillation, neurostimulators, TENS devices, radiofrequency catheter ablation, and therapeutic diathermy.

The most common advice given to PM patients comes from information provided by device manufacturers and regulatory institutions where, in general, it is recommended for patients with CIED to keep a “safety distance” of 15-20 cm or more between CIED and sources of EMI (the more powerful the source, the greater this distance should be). Patients with pacemakers and implantable cardioverter defibrillators are often advised to avoid relevant sources of EMI, either completely or, when being unable to do so, at least to try to keep the “safe distance” mentioned above.

It is important to note that device manufacturers have designed CIEDs so that they should function properly in vicinity of most household appliances and equipment, and therefore it is not expected that patients will encounter difficulties when they are exposed to them during normal daily use. The same should apply for various medical diagnostic/therapeutic devices and tools.

However, caution is needed as there are various devices present in our daily life, and while there are those that seem to be safe for use, such as gate metal detectors or handheld metal detectors, (8, 9) some of them can sometimes cause unexpected problems. (5-7, 10)

In conclusion, it could be said that the scope of this problem (EMI in CIED recipients) is relatively small – but relevant, and when issues occur, in most cases they are of a transitory nature and can easily be avoided. However, it is of outmost importance to have discuss the issue with patients that has a CIED, bearing in mind their specific situations and needs. Physicians should be aware of and familiarized with most common interactions of EMI and CIED.