Boston, MA - During a recent decade in which the number of automated external defibrillators (AEDs) sold grew 10 times, just over 20% of them were the subject of critical safety-alert or recall advisories, according to estimates reported here at the Heart Rhythm Society 2006 Scientific Sessions [1].

"One in five recalls is a high number for any product, let alone a life-saving product," coauthor Dr William H Maisel (Beth Israel Deaconess Medical Center, Boston, MA) told heartwire. "These advisories occur frequently, they affect a lot of AEDs, and the mechanisms in place to notify AED users are poor. . . . Potentially, there are a lot of recalled AEDs that have not been replaced or repaired."

As presented here by Dr Jignesh S Shah (Beth Israel Deaconess Medical Center), during the years 1996 to 2005 there was a steady and steep increase in the number of AEDs sold, from about 20 000 to almost 200 000, for a total of 775 387 units overall. During the same period, advisories were issued for 21.2% of all marketed units, including 37 advisories that applied to 164 102 AED units and 15 advisories involving 221 820 accessories, such as cables and electrodes.

To obtain their data, Shah and Maisel scoured the weekly US Food and Drug Administration (FDA) enforcement reports for AED-device and AED-accessory safety-alert and recall advisories defined as class I and class II, focusing only on those dealing with critical function issues and omitting less urgent class III advisories.

Examples of problems with the AED units themselves included a potential for shutdown before delivering therapy, incorrect electrocardiogram interpretation preventing appropriate therapy, and failure due to a faulty component. Among the included accessory problems was a potential for electrode failure due to excessive corrosion of the pads.

They also searched the FDA's Manufacturer and User Facility Device Experience (MAUDE) database for adverse events related to AED malfunctions observed during the decade, discarding any that were not confirmed by the manufacturer or by a healthcare provider on the scene and those that did not occur during a ventricular arrhythmia.

Of the database's 801 documented adverse events, 370 (46%) were confirmed as device malfunctions by the study's criteria. According to Maisel, there was no way to determine how many malfunctions occurred in devices that had been targeted in advisories.

The registration process for patients who receive implantable defibrillators generally allows both manufacturers and physicians to track them down when safety issues arise, Maisel observed. "But with an AED, you have no idea who will take it off the shelf and try to use it," he noted. "You can go to Amazon.com or a pharmacy and buy one. There's a registration card that you're asked to send in, but most people won't. . . . There needs to be some change to the mechanisms by which these devices are monitored.

"Individual healthcare providers should be responsible for monitoring their own AEDs and being aware of any advisories," Maisel said. "The FDA needs to do a better job of notifying the public and publicizing its advisories, and manufacturers need to do a better job of reducing their rate of recall and providing information to people about the reliability of their devices.

"If you go to O'Hare airport, there are potentially dozens of AEDs, and there is some person or some facility operator responsible for those devices. But I have great concern that those people aren't in the loop with regard to the issuing of these advisories and the notification that comes from the FDA, which is published on its website but may not get a great deal of notice or be circulated to the people who need to see it."