(SAN FRANCISCO) -- A new study reveals that headphones for MP3 players are safe for patients with implantable cardiac devices, as long as they are kept two centimeters away from the device.
Study author Kok-Swang Tan, a research scientist at Canada's health department, examined the magnetic interference of direct surface contact with 21 different headphone models at varied distances.
Tan observed no magnetic interference with any of the headphones when positioned at a distance of two centimeters or more, or just over a half inch.
However, interference can occur when headphones are positioned less than 2 centimeters away from the heart device, regardless of headphone connectivity, Tan says.
"It doesn't matter whether the music player is on or off, or whether or not the headphones are connected to the player," Tan said. "The static magnetic field in the headphones can still cause interference."
Tan presented his findings at the Heart Rhythm Society's annual meeting in San Francisco.
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