Medtronic is withdrawing electronic heart defibrillator wires from the market, after reports of malfunctions and at least five patient deaths.
About 235,000 patients worldwide have defibrillators that use the "Sprint Fidelis" wires implanted in their chests.
The tiny wires -- called "leads" -- connect the patients' hearts to the stopwatch-size defibrillators. Medtronic said the leads could fracture inside the patients' blood vessels, possibly causing the defibrillator to erroneously send a massive electrical jolt to the heart.
The defibrillators are designed to detect an irregular heartbeat and deliver one or more shocks to restore a normal rhythm.
If the device discharges erroneously, it could cause serious problems in at least some patients, medical authorities said.
Medtronic, the world's largest maker of electronic heart devices, said it is not recommending that all patients have the leads surgically removed, as the risk associated with the surgery could be higher than the risk of leaving the leads implanted.
Instead, the company said patients should consult their physician, who can reprogram the defibrillator to better detect problems with the leads.
The company provided few details about the five patient deaths that helped bring the problem to its attention.
Medtronic already faces more than 900 lawsuits alleging that its devices malfunctioned or failed to function. The wire problem could create a wave of litigation and bad publicity similar to the 2005 recall of defibrillators and pacemakers made by Guidant Corp.
The company said it made its decision to withdraw the wires and go public with the problem after consulting wit the U.S. Food and Drug Administration and with outside medical experts, including the president of the Heart Rhythm Society, which represents heart specialists.
The company said it has written to 13,000 doctors to alert them to the problem, which it said was first reported in March.
Published reports said the company has found the fracture rate on the Sprint Fidelis wires is 2.3 percent at 30 months, compared with 1 percent on average for other Medtronic leads.
