A battery longevity issue prompted Medtronic this month warn doctors about some 96,787 of its InSync III pacemakers, an action the FDA labeled a Class II recall, although Medtronic said only about 22,000 of the devices are still active.
The Fridley, Minn.-based medical device titan sent a letter to physicians dated November 2015, warning that a high battery impedance issue “can result in the battery’s inability to supply sufficient electrical current.” Through Oct. 27, 30 devices of 0.03% were confirmed to have experienced the issue, Medtronic said, noting that it’s impossible to predict which of the InSync II devices, which are no longer distributed, might be affected by the battery problem.
“Twelve (12) of the 30 devices had reports of unexpected loss of pacing capture. The other 18 devices experienced some form of erratic behavior, including early elective replacement indication (ERI), significant fluctuations in remaining longevity estimates, and inaccurate lead impedances. Through 27 October 2015, events associated with this issue have occurred in devices with implant durations of 53 months or more. Medtronic has received 1 report of a patient death, where it is possible, but unconfirmed, that this issue was a contributing factor,” the company said in the letter.
“Our modeling predicts an estimated failure rate between 0.16% and 0.6% for the remaining active devices,” Medtronic said.
The company recommended no action be taken for InSync III patients who are not dependent on their pacemakers.
“For pacemaker-dependent patients, physicians should carefully weigh the risks and benefits of device replacement to mitigate this issue on an individual patient basis,” Medtronic said. “The estimated per patient mortality risk of this issue (0.007% to 0.02%) is comparable to the estimated per patient mortality risk of complications associated with an incremental, early device replacement (0.005%).”
A Class II recall denotes the risk of “temporary or medically reversible adverse health consequences or where the probability of serious adverse health consequences is remote.”