BOSTON -- One in five automated external defibrillators (AEDs) in the past 10 years have been recalled because of malfunction concerns, found a report presented in mid May at the Heart Rhythm Society's 27th Annual Scientific Sessions. However, the researchers, who were led by William H. Maisel, MD, MPH, director of Pacemaker Device Service at Beth Israel Deaconess Medical Center in Boston, said that the number of recalls is small compared to the number of lives saved through use of the devices.

The Food and Drug Administration issued 52 advisories for AEDs or their accessories between 1996 and 2005, mostly for electrical and software problems. The recalls affected 385,922 devices.

Since 1996, the number of AEDS distributed annually has increased from 20,000 to 200,000. Some states require that health clubs keep a working AED on premises.