Protecting Your Pacemaker From Smartphones, Power Lines

Can mobile phones really disrupt your pacemaker or implantable cardioverter defibrillator (ICD)? Ten years ago, research indicated they could. That’s why the U.S. Food and Drug Administration recommended keeping mobile devices — and the radiofrequency energy they emit — at least 6 inches away from cardiac devices.

But technology has advanced since then. So, do people with pacemakers and ICDs still need to follow the 6-inches rule?

One European study says yes. A second study cautions lingering under power lines.

Why smartphones can make your heart skip

Pacemakers can mistake interference from a smartphone’s electromagnetic field for a cardiac signal. That can disrupt the pacemaker and cause your heart to beat irregularly. Extreme cases can trigger your ICD to shock your heart back into normal rhythm.

Glitches like those are not common, but still possible, according to the study.

More than 300 people — some with pacemakers and some with ICDs — tested three common smartphones (HTC One XL, Nokia Lumia and Samsung Galaxy 3). Each phone was placed directly over the spot where a cardiac device had been implanted. Phones made test calls over various mobile networks while electrocardiograms recorded participants’ heart function.

Out of all participants, only one was affected by smartphone use.

How to eliminate all risk

“Even in worst-case-scenario testing of phones and other mobile devices, there is little to worry about,” says cardiologist Bruce Wilkoff, MD.

Dr. Wilkoff was not involved in the study.

It is very unlikely that symptoms will occur with normal use, he says. Still, to be safe, Dr. Wilkoff does recommend one precaution: “Don’t put a phone in a shirt or jacket pocket on the same side as your pacemaker or ICD,” he says. “This will eliminate all risk.”

Some doctors also recommend holding phones to the ear furthest from the cardiac device.

What about power lines?

High-voltage power lines and substations could potentially trigger the same problems for pacemakers and ICDs. But, again, it’s unlikely, according to a second European study.

Researchers tested 40 cardiac devices, exposing them to a range of voltages. They discovered no major concern for people who wear cardiac devices — as long as they’re programmed normally.

“Walking, running, biking or otherwise crossing under power lines is safe,” says Dr. Wilkoff. “Staying under them for too long may be an unnecessary risk, however.”

It’s also worth noting that magnets in devices like the Apple Watch and Fitbits are another mild threat to those with pacemakers, too. For the vast majority of people with pacemakers or ICDs, the risk of any environmental interference is minimal, he notes.