Boston Scientific recently revealed that a medical device defect in its implantable cardiac defibrillators has killed at least one person. The defect is present in the company's Cognis and Teligen defibrillators which have already been implanted in over 233,000 patients worldwide.
"Engineering analysis indicates that the probability of malfunction decreases as implant time increases," Boston Scientific said in a press release posted on its website. "Boston Scientific will further analyze the failure mechanism and continuously monitor field performance of Cognis and Teligen devices."
The device malfunctions typically occur in the device transformer, which is used to multiply the low voltage of the defibrillator battery to the high voltage of a shock. The error occurs during a high voltage charging cycle and at least 26 patients have reported at a sudden heating sensation at the site of the implant, which was likely caused by rapid depletion of the battery.
Boston Scientific stated that it does not plan to update the safety labeling on its device and does not recommend any physician changes. The Boston Scientific update also notes that the malfunction occurs at a relatively low rate of 1 out of every 8,900 devices.
"Use of the Latitude remote monitoring system will provide notification of missing data between office visits, which may significantly reduce the time to detect a transformer malfunction, should it occur," the company said.
Source: Mass High Tech Business News, "Boston Scientific: Defibrillator glitch killed patient," Julie M. Donnelly, April 23, 2012