Guidant Defibrillator Woes Worsen

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Guidant Corp. said Friday it was telling doctors to stop using five models of its implantable cardiac defibrillators because a faulty switch could cause it to malfunction.

The announcement was the Indianapolis-based company's second safety advisory in a week for its defibrillators and covered two devices that last week it said could be repaired with reprogramming in a doctor's office.

The five devices included in the latest announcement are the Contak Renewal 3 and 4, Renewal 3 and 4 AVT, and Renewal RF. About 46,000 of the devices are in use, the company said.

Guidant said doctors "should discontinue implants of these devices pending further notice."

The company said it had informed federal regulators of its action and that the U.S. Food and Drug Administration may classify it as a recall. Officials with the government agency were not immediately available for comment.

The devices listed Friday have had at least four malfunctions. A fifth suspected case has not been confirmed, but no patients have been injured, Guidant said.