St. Jude Medical Inc. is warning patients that the batteries on thousands of its implantable defibrillators can quickly and unexpectedly deplete, in rare cases leaving them vulnerable should they need a shock from the device to restart their faltering hearts.
The premature battery depletion has been seen in fewer than 1 percent of the devices, the company said in letters sent to doctors and patients on Tuesday. Two people died after their devices failed to work correctly because of the drained battery, while 47 others reported dizziness or fainting. The warning applies to devices made before May 2015, which are in use in about 350,000 people worldwide. St. Jude’s shares declined on the news.