FRIDAY, Feb. 1 (HealthDay News) -- Portable music players such as the iPod don't cause electronic interference in implanted cardiac pacemakers, a new study claims.

Government researchers reported in the current issue of BioMedical Engineering OnLine that they measured the magnetic fields produced by four different iPod models -- a fourth-generation iPod; iPod with video; iPod shuffle; and iPod nano -- and measured the voltages delivered inside a pacemaker by the magnetic fields from the iPods.

They determined the music devices would have no impact on people with cardiac pacemakers.

"Based on the observations of our in-vitro study, we conclude that no interference can occur in pacemakers exposed to the iPods we tested," wrote U.S. Food and Drug Administration researcher Howard Bassen and his colleagues.

Over the past year, there have been a number of media reports about iPod interference with cardiac pacemakers. But those stories were based on a single incident where a person with a pacemaker experienced dizziness while using an iPod. During an examination, doctors conducted a test with an iPod and found it interfered with the patient's pacemaker.

The case was published in the journal Heart Rhythm and prompted discussions about the use of warning labels for portable music and video players, according to background information in a news release about this new study.

More information

The U.S. Food and Drug Administration has more about implanted cardiac pacemakers.