Smartwatches may trigger heart attacks in vulnerable patients: study

By Mark Waghorn via SWNS

Smartwatches such as Fitbits may trigger a heart attack in vulnerable patients, according to new research.

Wearable gadgets can interfere with medical devices such as pacemakers, say scientists.

Lead author Dr. Benjamin Sanchez Terrones, a computer engineer at Utah University, said: "This study raises a red flag.

"We've done this work in simulations and benchtop testing following Food and Drug Administration accepted guidelines.

"These gadgets interfere with the correct functioning of the CIEDs (cardiac implantable electronic devices) we tested."

They also included cardioverter defibrillator (ICD) and cardiac resynchronisation therapy (CRT) implants.

Dr. Sanchez Terrones said: "These results call for future clinical studies evaluating the translation of our findings to patients wearing CIEDs and using these wearable devices."

High-tech watches that record exercise levels for the health conscious are potentially deadly for a small group of people, warn the international team.

They also include at-home smart scales and smart rings that utilize a sensing technique called bioimpedance.

It emits a very small, imperceptible current of electricity measured in microamps into the body.

The response is measured by determining the individual's skeletal muscle or fat mass, level of stress or vital signs like breathing rate.

Investigators evaluated the functioning of CRT devices while applying the same electrical current.

Dr. Sanchez Terrones said: "Bioimpedance sensing generated an electrical interference that exceeded Food and Drug Administration-accepted guidelines and interfered with proper CIED functioning."

The results apply to smartwatches like the Samsung Galaxy Watch 4 or the Fitbit Aria 2 smart scale.

Simulations and lab tests suggested they could causes unnecessary shocks to the heart.

Dr. Sanchez Terrones said: "Our findings call for future clinical studies examining patients with CIEDs and wearables."

In the case of a pacemaker, which sends small electrical impulses to the heart when it is beating too slowly, the bioimpedance’s tiny electrical current could trick the heart into thinking it is beating fast enough, preventing the pacemaker from doing its job when it is supposed to.

Co-author Prof. Benjamin Steinberg, also from Utah, said: "We have patients who depend on pacemakers to live.

"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."

Implantable cardioverter-defibrillators not only act as a pacemaker but can also shock the heart to restore a regular heart rhythm.

A wearable device with bioimpedance could trick the defibrillator into delivering the patient an electric shock, which can be painful.

Nearly all, if not all, implantable cardiac devices already warn patients about the potential for interference with a variety of electronics due to magnetic fields, such as carrying a mobile phone in your breast pocket near a pacemaker.

But Dr. Sanchez-Terrones says this is the first time a study has discovered problems associated with a gadget's bioimpedance sensing technology.

He said: "The scientific community doesn't know about this. No one has looked at whether this is a real concern or not."

The research does not convey an immediate or clear risk to patients who use these kinds of wearable devices, but it's a first step for further study.

Prof Steinberg said: "We need to test across a broader cohort of devices and possibly in patients with these devices.

"Ultimately, more studies are needed to evaluate the clinical translation of our findings and ensure the health of our patients."

In the UK pacemaker implantation is one of the most common types of heart surgery carried out with many thousands fitted each year.

Dr. Sanchez Terrones said: "Our research is the first to study devices that employ bioimpedance-sensing technology as well as discover potential interference problems with CIEDs such as CRT devices.

"We need to test across a broader cohort of devices and in patients with these devices. Collaborative investigation between researchers and industry would be helpful for keeping patients safe."

The study is published in the journal Heart Rhythm.