Experts say that the Sprint Fidelis leads are more than twice as likely to fracture as other Medtronic lead wires. When this occurs, it can cause the defibrillator to stop working, or can cause the device to deliver repeated, painful shocks to the patient. The Food and Drug Administration has received at least 599 reports of malfunctioning Sprint Fidelis wires. Of this group, at least 204 patients suffered excessive shocks due to defibrillator wire problems.

Medtronic announced that it will no longer sell the Sprint Fidelis wires and says that any of the leads which are still on shelves should be returned to the company. Although the FDA says that the 235,000 patients who have already received one of the recalled leads should not have them removed, it has asked doctors to adjust lead wires at these patients’ next visits in order to prevent fractures from occurring.

Medtronic is already facing more that 1,000 defibrillator lawsuits over faulty defibrillators that were recalled in 2005 due to battery problems. Financial analysts say that the company could face even more lawsuits over the defibrillator wire problems with the Sprint Fidelis leads.