Sprint Fidelis Lead Failure Could Be Due To Generator Replacement: Study

According to a study published earlier this year, there appears to be a connection between the exchange of implantable cardioverter-defibrillator generators and a subsequent failure of recalled Medtronic Sprint Fidelis leads, which were removed from the market in 2007, but remain in use among thousands of people throughout the United States.

The Medtronic Sprint Fidelis is a small lead wire, which is used to connect the implantable defibrillator to the heart and carry a potentially life-saving electrical jolt if needed to restore normal heart rhythm.

A Medtronic Sprint Fidelis recall was issued on October 15, 2007, after it was confirmed that the small wires were prone to fracture or break. This exposed patients to a risk of unnecessary shocks or failure of the device to deliver the necessary electrical charge when needed.

Approximately 268,000 of the leads were implanted prior to the recall, and more than 100,000 patients still have a Sprint Fidelis lead. While patients with the recalled leads have been more closely monitored since the recall, they were left with few options following the recall, since it is especially risky to attempt to remove and replace the small wires, which are fed through veins that lead to the heart.

Although the implantable defibrillators are designed to be replaced every 5 to 10 years, the lead wires are often kept in place and used with the new device. However, this new research raises questions about whether individuals with one of the recalled Medtronic leads may be better off having their lead replaced at the time of the generator exchange.

In a study published online in June by the medical journal Heart Rhythm, researchers determined that there is a higher than expected rate of lead failure associated with exchange of the generator, often occurring within three months.

Researchers examined data on 1,366 patients who received a Medtronic Sprint Fidelis lead prior to the recall, of which 479 were still being actively followed. As part of the study, 72 of the patients with a functioning lead had their generator exchanged without replacing the leads, and 15 of the leads subsequently failed, suggesting that generator exchange increased the rate of lead failure substantially when compared with matched controls.

Approximately 60% of those that experienced problems after generator replacement had the lead fail within 3 months.

“The replacement procedure itself seems to be the cause, since most of the failures occur within three months of the procedure,” according to the group, led by Dr. Joshua D. Lovelock of the Emory University School of Medicine, located in Atlanta. “There are no clinical parameters that predict lead failure after ICD exchange, suggesting that all Fidelis patients should be considered at risk after a generator replacement.”

The study may provide relevant information for individuals who received certain St. Jude Riata defibrillator leads, which were recalled last year amid reports of failure and problems. In that case, the small wires have been found to poke through the insulation. Individuals who received one of the recalled St. Jude lead wires have been left with similar uncertainty to those who had a Medtronic Sprint Fidelis lead, since they face the same risks associated with attempting to remove and replace the leads.