Magnets in wearables and smartphones could interfere with pacemakers

The FDA has published a new report that recommends patients with implanted medical devices such as pacemakers or defibrillators keep smartphones and watches at least six inches away from the implanted devices. The FDA its study after reports of smartphones and watches interfering with implanted medical hardware. The investigation was affiliated with the Center for Devices and Radiological Health at the FDA.

Researchers on the study say their work confirms the FDA recommendation that consumer electronic devices that could create magnetic interference, such as cell phones and smartwatches, be at least six inches away from any implanted medical devices. In addition, the study says that users who have implanted pacemakers or defibrillators in particular need to be wary of the six inches of distance required.

Concerns were raised as some modern smartphones, particularly devices from Apple, now use magnets inside to help them stick to chargers and other accessories. Researchers reviewed recently published articles describing the potential for newer phones and wearables with high field strength magnets to temporarily interrupt the normal operation of implanted electronic medical devices.

Based on a review of those previously published studies, the team conducted its own testing to confirm and devise appropriate recommendations for patients and medical caregivers. The study notes that implanted electronic devices for cardiac support have a magnet mode designed for when the wearer is undergoing a procedure with a potential for electromagnetic interference or when their implant has to be turned off during the treatment.

The problem for patients with these implanted devices is that the feature can be triggered accidentally when exposed to a magnetic field greater than 10G. Typically magnets in that strength range are easy to avoid as they are located inside speakers or power tools. However, when the team tested iPhone 12 and Apple Watch 6 models at various distances, they found all of the devices have magnetic fields significantly higher than 10G in close proximity. They were powerful enough to force implanted medical devices into magnet mode. While there is certainly a risk, the researchers are clear that they are aware of any issues associated with the magnets and the risk to patients is currently low.