Dr. Carsten Lennerz, cardiology resident in Germany, presented results of a study on Monday at the European Heart Rhythm Association (EHRA) Eurospace Cardiostim.
“Pacemakers can mistakenly detect electromagnetic interference (EMI) from smartphones as a cardiac signal, causing them to briefly stop working. This leads to a pause in the cardiac rhythm of the pacing dependent patient and may result in syncope. For implantable cardioverter defibrillators (ICDs) the external signal mimics a life threatening ventricular tachyarrhythmia, leading the ICD to deliver a painful shock,” Dr. Lennerz said.
The study conducted by a group of researchers analyzed 308 patients. 147 of the patients had pacemakers, 161 patients had Implantable Cardioverter Defibrillators (ICDs) and 65 patients had Cathode Ray Tubes (CRTs). They frequently recorded electrocardiograms (ECGs) and checked for interference caused by nearby smartphones.
The researchers determined it is uncommon for smartphones to cause interference with these medical devices; however, they suggested patients keep their distance from smartphones.
“Interference between smartphones and cardiac devices is uncommon but can occur so the current recommendations on keeping a safe distance should be upheld. Interestingly, the device influenced by EMI in our study was MRI compatible which shows that these devices are also susceptible,” according to the group.
“Everyone uses smartphones and there is the possibility of interference with a cardiac device if you come too close. But this doesn’t mean that those with implanted cardiac devices need to ditch their phones, but it does mean that they shouldn’t place them ‘directly over’ their cardiac devices,” Christof Kolb, senior author of the study, told HealthDay News.
Editor’s Note: One of Interference Technology’s longtime readers and advisers wrote in with a few thoughts on this smart phone and cardiac device issue. Below is an edited excerpt from his letter:
‘Doctors implant computers in [people’s chests when they have heart failure]. Notice I that I don’t call this device a “pacemaker.” Nowadays, these devices are much more than pacemakers. They are indeed micro-computers. They not only track a heart’s behavior, they store data and can do things like communicate each evening, sending such data about the person’s status to a central storage at the doctor’s office over a special telephone link.
The material in this article refers to “smart phones.” Specifically [my concern] is the term “smart.” I realize that “smart” is the word that the doctors actually used, and of course Interference Technology is free to find refuge behind this fact. But a more accurate fact is that any cell phone, whether smart or not, should never be placed close to the computer in one’s chest and the wires leading to a heart. I say this both because of my knowledge about the physics involved and because of the material/caution contained in the literature [patients] receive in the info package that comes with the device. Such EMI has a remote but real chance of causing a fatal outcome, this being more likely than the article (or the doctors?) intimate. Why fatal? Mainly when the patient is engaged in activities like driving a car.
Sooner or later the device will likely “fire” [and save a life]. [Patients are] cautioned to never keep their phone in their shirt pocket (which is almost directly over the implanted computer). As you likely know 1) cell phones have to transmit even when not in use by the owner so as to let the cell system know in which cell they are located. Such incidental transmissions will occur within fractions of an inch of the “pacemaker” and its wires to the heart; and 2) it’s the wires that are the main cause of the EMI susceptibility…. that, and the limited ability to establish a proper ground for the device. This can negate the protection that filtering protection installed by the manufacturer is intended to provide.
Bottom line is that [one has] had to use a safety pin through the top of a shirt pocket as a reminder to never to put a cell phone there. A cell phone that, being more than several years old, is far from “smart”.’
