SALT LAKE CITY, Utah (ABC4) — A new study from the University of Utah shows that, for a small group of individuals who have implantable cardiac electronic devices, some wearable gadgets could put their health at risk.

Published in the latest edition of the scientific journal Heart Rhythm this week, researchers at the university studied the effect devices like wearable smartwatches, at-home smart scales, and smart rings utilizing bioimpedance have on those with cardiac implantable devices (CIEDs) such as pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy devices.

Bioimpedance, a type of sensing technology, emits very slight electrical currents through the body, where the response is then measured to determine a person’s body composition including skeletal muscle mass, fat mass, and even stress levels.

Comprehensive testing of bioimpedance on several common cardiac CRT devices showed that the small electrical currents from wearable gadgets tested could interfere with or confuse cardiac implantable devices, causing them to operate incorrectly.

As pacemakers also send small electrical impulses to the heart when it’s beating too slowly, testing of bioimpedance indicated that its currents can trick the heart into believing it’s beating fast enough.

“We have patients who depend on pacemakers to live,” Benjamin Steinberg, an associate professor, cardiac electrophysiologist, and co-author of the study, says. “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.” 

Even further testing on medical devices like implantable cardioverter-defibrillators, meant for shocking the heart to restore regular rhythm, showed how bioimpedance could trick the device into giving patients an unnecessary and painful electric shock.

A new study from the University of Utah shows that wearable devices such as certain smartwatches and smart scales might possibly interfere with implantable devices like the implantable cardioverter defibrillator shown here.

According to the University of Utah’s electrical and computer engineering assistant professor and co-author, Benjamin Sanchez Terrones:

“This study raises a red flag… We have done this work in simulations and benchtop testing following Food and Drug Administration accepted guidelines, and these gadgets interfere with the correct functioning of the CIEDs we tested.” 

The authors of this study also emphasized that this research does not convey an immediate or clear risk to patients using these wearable devices, only that these findings are a first step for further study.

“These results call for future clinical studies evaluating the translation of our findings to patients wearing CIEDs and using these wearable devices,” Sanchez Terrones explains.