On December 11, 2007, a 48-year-old man underwent surgery to have his Medtronic defibrillator and lead wires replaced after the Sprint Fidelis lead was linked to five deaths.

A defibrillator is meant to deliver electric shocks to the heart to restore normal rhythms if a patient’s heart starts beating erratically. During implantation of the device, lead wires are also implanted that connect the defibrillator to the patient’s heart. One of the most widely-used leads, the Sprint Fidelis lead, was recently pulled from the market when its’ manufacturer, Medtronic, announced that the Sprint Fidelis lead carries a higher risk of failure (fracture) within the first 30 months of use than its predecessor product, the Sprint Quattro lead.

If a lead fractures it could prevent the defibrillator from firing when needed. Fractured leads may also suffer from disruptions in their sensing mechanism, causing them to deliver unnecessary and perhaps repeated shocks.

In some instances a defibrillator is implanted to serve a dual purpose, also acting as a pacemaker for the patient’s heart. In these situations the failure of a lead like the Sprint Fidelis lead could have devastating consequences for the patient.

The December 11 surgery came two months after Medtronic warned doctors and patients that the lead might break. The warning has left many patients wondering if they should have the faulty lead removed, or leave it in place and hope it does not fracture.

The risks involved during removal surgery, besides infection, include perforation of the heart and veins in the chest. Some patients also face a risk of damage to the heart valve through which the Sprint Fidelis lead lead was threaded.

Each lead replacement procedure can cost $12,500 or more. Medtronic has offered only to contribute a replacement lead and $800 towards the procedure, and insurers are debating whether to cover the surgery on a case-by-case basis.

While most Sprint Fidelis lead users will not need the operation, all have been advised to check with their doctors. The number of patients potentially affected by the faulty leads – nearly a quarter of a million – makes this the most widespread heart device problem in the country’s history. It is the latest example of errors in a medical device industry that has been plagued by design defects, lax quality control, and product recalls such as the Guidant defibrillators in 2005 that were linked to seven deaths.

“It seems like a good time to figure out where we are in regulating leads and what we can do better,” said Daniel G. Schultz, director of the FDA’s center for devices and radiological health.

A Detroit woman said her husband had his Sprint Fidelis lead reprogrammed to safer settings by a Medtronic representative, but still planned to seek a second opinion at the Cleveland Clinic.

“Maybe nothing will happen,” she said, “but if it does I want him to be a patient of someone known to be a high-volume expert.”

In October 2007, Medtronic said the Sprint Fidelis lead fractures at a higher rate than the Sprint Quattro, which Fidelis has been displacing since 2004. Data from Medtronic suggests 2.3 percent of Fidelis implants fracture within 30 months. While experts believe data from the lead’s manufacturer is likely conservative, even at these estimates some 4000-5000 patients in the United States are at risk of fracture.

Dr. Raymond H.M. Schaerf, a surgeon at Providence St. Joseph Medical Hospital in California, has removed six Fidelis leads from patients since the October 2007 warning. Dr. Schaerf also said he has turned 10 patients away, though, indicating replacement procedures are too risky in those particular patients’ situations.

Robert G. Hauser, a Minneapolis cardiologist, said he is organizing a registry to track performance of the Sprint Fidelis lead and other leads, in order to get a better grasp on the specific risks involved.

Source: Barnaby J. Feder, “Patients wonder whether to replace a wire that might fail,” New York Times, December 13, 2007.