• Posted April 9, 2025

Tasers Can Interfere With Heart Implants, Study Says

People with heart implants could be in trouble if they’re hit with a powerful handheld taser, a new study says.

A heavy electrical charge delivered by a taser could cause a pacemaker or implanted defibrillator to malfunction, researchers report in the journal Heart Rhythm.

As a result, the implant might stop working or deliver its own shock because it has inappropriately detected an abnormal heart rhythm, researchers said.

“Commercially available handheld electro-shockers pose a relevant risk of interaction when applied in proximity to cardiac implantable electronic devices (CIEDs),” senior researcher Dr. Lars Eckardt, a cardiologist at University Hospital Muenster in Germany, said in a news release.

More than 1,000 deaths have been reported in association with police use of tasers in the United States, researchers said in background notes.

For the new study, researchers tested six pacemakers and 10 implantable cardioverter-defibrillators from different manufacturers.

The devices were all implanted beneath the muscle in the chests of butchered pigs. The team then delivered shocks to the pigs’ skin using three different taser devices, to see how the implants would respond to the charge.

Researchers used handheld tasers that directly contact a person’s skin, rather than taser pistols used by police that send current through wired darts. Police may also use the handheld tasers.

The PowerMax taser carried the largest shock, at 500,000 volts, and it had a high potential of interaction with all the tested heart implants, results show.

In all 16 devices tested, the PowerMax caused them to stop delivering electrical stimulation. Further, six of the 10 IEDs tested interpreted the shock as a high heart-rate episode, results show.

Less powerful tasers carrying charges of 250,000 volts and 50,000 volts had a significantly reduced risk of interfering with heart implants, researchers said.

Nevertheless, the 250,000-volt taser caused 10 of 16 devices to stop delivering stimulation, results show.

Researchers said they were surprised to find that implanting the devices beneath the muscle did not significantly reduce the risk that a taser charge would interfere with their function.

Results also showed that a powerful taser shock could interfere with a heart implant even if the charge entered the body away from the chest.

“We expected the distance between the electro-shocker application and the CIED implantation site to have a greater impact on the risk of interaction than it did in the present study,” lead researcher Dr. Felix Wegner, a cardiologist at University Hospital Muenster, said in a news release.

“These unexpected findings indicate that electro-shocker applications to a large part of a patient with a CIED’s body may pose a relevant risk of interaction with the respective CIED,” Wegner added.

None of the devices was directly damaged by the shock, researchers noted.

More information

The American Heart Association has more on implantable heart devices.

SOURCE: Elsevier, news release, April 9, 2025