Tasers are often touted as a non-lethal alternative to guns, but in some cases a shock from a stun gun can be just as deadly as a bullet wound. In an effort to curb accidental deaths, researchers have devised a new Taser feature that tracks heart rate, Vocativ reports.

When a victim is tased, a low-amp, high-voltage shock is sent through their central nervous system. The painful muscle contractions that ensue are usually limited to muscles associated with mobility, but in rare cases they move to the heart. This results in cardiac defibrillation which can sometimes be fatal. A study conducted by Amnesty International found that Tasers were involved in at least 500 deaths in the U.S. between 2001 and 2012.

Researchers at the Wake Forest University School of Medicine set out to make a better Taser by designing it to take electrocardiographs (ECGs). As the Taser-owner administers a shock, the ECG, in theory, relays the victim’s heartbeat and heart rate information to the person with the Taser, giving them a chance to stop before it’s too late.

According to their report published in the Journal of Forensic and Legal Medicine, none of the participants the device was tested on experienced any heart-related distress when tased. It may be too early to say how effective the feature would be in a life-or-death situation, but with Tasers gaining popularity in police departments across the country, it's a crucial first step.

[h/t Vocativ]

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