A team of researchers has found that St. Jude Medical’s defective Riata and Riata ST leads have directly caused 22 deaths or 31 percent of all deaths involving the lead family.
Most surprisingly, the deaths were caused by electrical malfunction at high voltages — and not because of lead wires coming out of their insulation. The so-called externalized conductors were the main reason that the U.S. Food and Drug Administration slapped St. Jude (NYSE: STJ) with a Class I recall in December.
The findings of the study, whose manuscript was accepted for publication in the Heart Rhythmjournal, are bound to create a vexing issue for St. Jude, which has attempted to deflect the fear that externalized conductors might be a problem for its newer Durata family of leads. Specifically, the company’s CEO Daniel Starks has argued that Durata leads have a coatingthat is much more resistant to insulation abrasion. Others have argued that aside from the coating, the Durata is similar in design to the older generation of leads.
The study “Deaths Caused By the Failure of Riata and Riata ST Implantable Cardioverter Defibrillator, found that out of a total of 133 deaths reported in an FDA database, 71 involved Riata and Riata ST leads, with 22 of them caused by lead failure.
That’s 31 percent lead failure rate leading to death, compared with 8 percent (5 of 62 deaths) caused by Medtronic’s Sprint Quattro Secure leads. The fatalities involving Riata and Riata ST lead failure were caused most commonly by short circuits between high voltage components. When that kind of electrical malfunction occurred, the ICD failed to defibrillate.
None of the deaths was due to externalized conductors, one outcome of lead abrasion, although some of the Riata family of leads showed this problem.
Of the 141,000 Riata and Riata U.S. implants, approximately,79,000 remain active, the study noted. St. Jude voluntarily pulled the devices from the market in December 2010.
“Doctors need to place these patients on very close monitoring,” said Robert Hauser, one of the authors of the study and a senior consulting cardiologist at the Minneapolis Heart Institute. “We need to figure out what the predictors of the failure is.”
He noted that the short-circuit issue is still relatively rare, but added that compared to another high-profile lead recall involving Medtronic’s Sprint Fidelis family of leads, the Riata lead failure is more troubling.
“Sprint Fidelis was rarely associated with death; it was a low voltage issue,” Hauser noted. “This is a high voltage problem, which is more serious.”
In fact, the study is urging St. Jude to “conduct studies focused on the behavior of measurable electrical parameters prior to lead failure. Algorithms are needed that can detect electrical abnormalities before short-circuits occur.”
A St. Jude Medical spokeswoman said that “abrasion of silicone leads is acknowledged within the clinical community as a well-known clinical risk” and that led the company to develop the Optim technology which insulates leads making them several times more resistant to insulation abrasion than older, silicone-only defibrillation leads.
“We have three large ongoing prospective registries monitoring the performance of our Durata leads, which continue to demonstrate an abrasion free rate of 99.9%,” said Amy Jo Meyer, the spokeswoman in an e-mail. “The data from those studies is also being validated by PHRI, an independent research institute.”
By Arundhati Parmar
Arundhati Parmar is the Medical Devices Reporter at MedCity News. She has covered medical technology since 2008 and specialized in business journalism since 2001. Parmar has three degrees from three continents - a Bachelor of Arts in English from Jadavpur University, Kolkata, India; a Masters in English Literature from the University of Sydney, Australia and a Masters in Journalism from Northwestern University in Chicago. She has sworn never to enter a classroom again.More posts by Author
I have leads outside the insulation but there does not seem to be a path forward to resolve the issue. The leads have separated quite a distance from the sheath. I know if I was dealing with anything else I would replace the leads but the real issue is with the barb that attached the lead to the heart.
My son has this lead for the past 6 years. He is 24 years old, tall and very active. It appears that he may need to have this lead removed and replaced. Can you tell me what Dr and medical center in the nation has removed the most riata leads?
6 DURATA paltient deaths in MAUDE From MAUDE database, searching Durata. 2054911 - pt death, no HV therapy 2069033 - pt death, no episodes? 2176257 - pt death following inappropriate shocks 2088952 - pt death, no shock and two possible "externalized conductors": 2157205 and 2156832 and even though the new designs are "perf-less" there were two deaths that may or may not have been attributed to perf: 2015172 and 2084488 the .
There is a big potential here for biased authors on the study. Medtronic is based out of Minneapolis too. The Durata lead family is the most researched HV lead in history with 6 years of data and 278000 implants. There have not been any major issues with Durata or even Riata with optim coating. Most of the issues reported are for a very small area of leads which is the uncommon single coil riata silicone. There is clearly an increased risk with this one type of hv lead. FDA did not recommend extraction like they did with Medtronic Fidelis which had issues with welds and connections within lead. It is a recall and the advice is to closely monitor these patients without exposing them to more risks by doing xrays, or worse surgery to extract.