New Research Suggests Sprint Fidelis Guidance Should Be Reviewed


Findings from research published in January’s “Circulation” publication and reported by Massdevice, suggest Medtronic’s Sprint Fidelis Implantable Cardiac Defibrillator problems may be greater than had been thought. According to the paper, looking at numbers for nearly half of all Sprint Fidelis implants in Canada, the rate of failure appears to be climbing, prompting some doctors to recommend that the devices be replaced before they show signs of failure.


Around 268,000 Fidelis leads were implanted in patients worldwide before Medtronic suspended shipments in October 2007. This new research pertains to data from Canada, specifically all 23 Canadian centers licensed to perform implantable cardioverter-defibrillator procedures, who reported their data to the Canadian Heart Rhythm Society Device Committee. The researchers looked at more than 3,000 Sprint Fidelis implants performed at 11 of the centers in Canada, Cardiovascular Business reported. Failure rates for the implants grew from 0.2% at 1 year, to 2.1% at 2 years, 5.3% at 3 years, 10.6% at 4 years and 16.8% at 5 years for the total population, data showed.

Researcher comments

“The rate of Fidelis failure continues to increase over time, with failures approaching 17% at 5 years,” the researchers wrote in the January issue of Circulation. “Our data suggests that Fidelis replacement should be strongly considered, at the time of generator replacement.”

“The failure rate in this study and other reports is higher than Medtronic has reported from their own data,” according to the researchers. “This is possibly explained, at least in part, by variable center failure rates and perhaps bias toward reporting data from centers with higher rates. In the current study we controlled for this by selecting centers from high and low strata of failure rate.”

“The defective leads are implicated in more than 100 deaths, although Medtronic has said, and indeed we have reported, that only 13 fatalities had the leads as a “possible or likely contributing factor.”

Guidance change?

Medtronic’s physician guidelines, last updated in April 2011, recommend that surgeons take no action on functioning leads in normal circumstances. In the event of a device change-out or upgrade procedure, however, the company recommends that surgeons consider patient factors and device model failure rates in determining whether to leave the functioning leads intact or replace them. This new research appears to demand a modification or at least review of that guidance.

Medtronic comments 

“Medtronic’s Independent Physician Quality panel routinely reviews external publications related to Fidelis, as well as our own information to ensure that their patient management recommendations remain up to date,” company spokesman Chris Garland told MassDevice in an email. “At this time, there are no changes to our patient management recommendations.”

Earlier this year the subject of Implantable Defibrillator failure due to externalised leads among St Jude’s Riata range (also recalled) was discussed by an eminent expert group who reiterated that they would not prophylactically remove at risk leads, but would monitor their condition.

Source: Massdevice, Circulation,