Its defibrillators are faulty, company says

MINNEAPOLIS - Recalls had already tarnished the reputation of implantable defibrillators when Medtronic warned doctors yesterday that the wires connecting a patient's heart to its device can break too often.

The company told doctors to stop using the Sprint Fidelis wires after linking five deaths to breaks in them. The company said the wires failed slightly more often than thicker wires they were meant to replace. Medtronic pacemakers are not affected.

The Fidelis wire, or lead, is used on about 60 percent of Medtronic defibrillator implants, said RBC Capital Markets analyst Philip Nalbone.

Defibrillators are "a critical product, and it's their flagship lead," Nalbone said of Medtronic Inc., whose shares dropped 11 percent.

A defibrillator monitors a patient's heartbeat; if it senses an abnormal rhythm, it delivers a shock to reset the heart to a normal beat. A defibrillation system consists of a device implanted near the shoulder with one or more leads connecting the device to the heart.

A series of industry recalls since 2005 has led some patients to avoid getting a defibrillator and some doctors to treat their symptoms with drugs instead of a device implant.

Before the recalls, the number of implantable defibrillators sold grew at double-digit rates, but Piper Jaffray analyst Timothy Nelson estimated that they declined 3 percent to 168,000 in 2006 and will be nearly flat this year.

The Sprint Fidelis was introduced in 2004 with thinner leads and was intended to replace the Sprint Quattro leads in use since 2001. But Medtronic said it noticed that after 21/2 years in patients, 99.1 percent of the Quattros were still viable vs. 97.7 percent of the Fidelis. Medtronic said the difference was not statistically significant but would have become significant as more were implanted.

A fractured lead "can cause the defibrillator to deliver unnecessary shocks or not operate at all," said Daniel Schultz, director of the Food and Drug Administration's Center for Devices and Radiological Health.

Medtronic did not call its response a "recall," but the FDA did. Neither one recommended removing the devices if no other problems have been detected. Medtronic said patients would be more likely to get complications from removing the leads. It said it could reprogram the device to beep if a lead has broken.

More than 268,000 of the leads have been implanted. Medtronic and the FDA estimated that breaks have occurred in less than 1 percent.

The Sprint Fidelis models affected are 6930, 6931, 6948 and 6949. Patients with those leads were advised to contact their doctors. Patients who are unsure what they have can call 1-800-551-5544 or go to www.medtronic.com/fidelis.