People fitted with pacemakers could be at risk if they or their partner wears a smartwatch, after US scientists found that electric signals from fitness trackers can cause potentially deadly interference in heart devices. Fitness gadgets work by sending a small, imperceptible current of electricity into the body, but researchers say it can disrupt the electrical pulses that keep heart implants functioning.
Experts from the University of Utah warn that the current could trick pacemakers into thinking the heart is beating correctly when it needs help, or give an unneeded painful electric shock to people with internal defibrillators. Although the electrical current cannot pass though the air between people, it could flow from one person to another if they are touching, the researchers also warned.
It suggests that people could be at risk from partners, children or other family members if they share close contact. “We have patients who depend on pacemakers to live,” said Benjamin Steinberg, an associate professor of medicine and cardiac electrophysiologist from Utah. “If the pacemaker gets confused by interference, it could stop working during the duration that it is confused. If that interference is for a prolonged time, the patient could pass out or worse.”
Pacemakers and cardiac defibrillators are designed to keep a patient’s heart beating regularly and not too slowly by sending electrical pulses. Currently, people with pacemakers are warned to keep mobiles, tablets, and smart watches at least six inches away from pacemakers because magnets inside can stop heart devices working. Even strong fridge magnets can cause problems, as well as induction hobs, electric toothbrushes and stereo speakers. But until now, no one had considered that the electric current could also be coursing through the body and interfering with implantable heart devices.
Fitness trackers use bioimpedance sensing technology which sends an electrical current into the body then measures the response to determine skeletal muscle mass, fat mass or stress levels. The researchers showed the interference in lab conditions, and have called for testing in patients. “This study raises a red flag,” said Benjamin Sanchez Terrone, who is an expert in electrical and computer engineering at Utah. “These gadgets interfere with the correct functioning of the cardiac implantable electronic devices we tested.” And they warned that even touching someone with a fitness tracker could be enough to cause interference to heart devices. “Being near is not enough since, unlike the magnetic field, electrical current can’t ‘jump’ from one person to another through the air,” he added.
(The Daily Telegraph, London)
