Battery Issues Prompt Recall of St. Jude Eon and Eon Mini Pain Implants
Friday, August 31, 2012
St. Jude Medical has recalled its Eon and Eon Mini Pain Management implants because of issues with their
batteries. According to a report from Mass Device, at least three patients suffered 1st or 2nd degree burns when batteries overheated while recharging. Apparently, hundreds of people have had the St. Jude Eon and Eon Pain Management devices removed for either recharging problems, or because the batteries failed early.
According to Mass Device, the problems have already spawned a personal injury lawsuit filed by a patient alleging that the battery in her Eon Mini model 3788 was defective. In that case, the implant was surgically removed when the battery failed after just six months.
St. Jude said it had received 214 reports as of June 30 that its Eon Mini model 3788 “lost the ability to communicate or recharge” because of cracked welds in the batteries, “resulting in loss of pain relief and subsequent explant.” In a letter issued July 26, St. Jude said an earlier analysis of the problem indicated moisture was the cause of weld cracking. However, with the occurrence of additional weld cracks, the company stated its “investigation has determined that the current weld cracks are not attributed to moisture within the battery.” Further analysis has revealed “a need to more frequently maintain and replace certain tools during the internal battery welding process by a St. Jude Medical supplier in order to assure complete alignment between the welding apparatus and the battery.” St. Jude said in the letter that it’s taken steps to correct the problem with its battery supplier, according to Mass Device.
Doctors have been advised to check the serial numbers of any Eon Mini implants in their inventory or that have already been implanted. Any un-implanted devices on the list should be returned to the company for a free replacement. Affected devices that have already been implanted in patients should not be automatically explanted but closely monitored for the duration between battery rechargings and for sudden power loss. St. Jude will provide a free replacement for any Eon Minis that require replacement due to weld failures within the inner battery.
The company also received 325 reports that the Eon Mini and Eon implants overheated during re-charging. Of those, 72 patients required surgical removal, and 3 suffered 1st- or 2nd-degree skin surface burns. “Heat generation during charging is a result of energy dissipation that occurs when an electromagnetic field is used to inductively transfer energy between 2 objects,” St. Jude said in a second letter dated July 26. “During a charging session, patients may feel an increase in temperature at the IPG implant site, but should not feel discomfort or pain.”
Patients who feel discomfort or pain should stop charging until the discomfort subsides, then adjust the position of the charging antenna. More frequent recharging for shorter durations, and avoiding inserting the antenna between the body and a chair or sofa that might trap heat could also alleviate the problem. If the problems persist despite these remedies, St. Jude said a company represented should be contacted for an evaluation.
