Troubling Flaws in a Heart Device Shake Implant
SAUSALITO, CA (ASRN.ORG) -- Last October, a high school football coach named Greg Jessee was standing on the sidelines watching his son play when he felt a jolt to his chest. The heart defibrillator implanted in him five years earlier was firing wildly. The next jolt made him double up. The one after that knocked him unconscious.
In the hospital, doctors discovered that the cable, or lead, connecting the defibrillator to his heart had failed and that the electrical wires inside it had worked their way out through the lead’s coating. Mr. Jessee, 50, said his doctor quickly notified the device’s producer, St. Jude Medical, about the incident.
It was not the first report to the company about problems with defibrillator leads. Last summer, researchers in Northern Ireland reported that tests of patients who received the St. Jude lead showed that wires were protruding out of their casing in 15 percent of them.
Doctors and the company are now trying to understand the scope of the problem, but experts say it is extremely distressing because the wires are particularly dangerous to remove and also may pose dangers if they are left in.
For the heart device industry, the problem with the St. Jude leads is the third highly visible safety episode in the last seven years. As such, it is raising questions about whether the industry is adequately scrutinizing the safety of heart devices or whether the Food and Drug Administration needs to take a more aggressive role. A defibrillator is a device that sends out an electrical jolt to interrupt a potentially fatal heart rhythm and restore the heart to normal beating.
Since 2005, St. Jude’s two major competitors — Guidant, which sold its heart unit in 2006 to Boston Scientific, and Medtronic — have both faced instances in which patients were killed or injured by flawed products. Device producers have since adopted safeguards to alert them to problems before too many patients are injured.
Officials at St. Jude Medical, one of the nation’s biggest producers of heart devices, insist they acted appropriately in warning doctors about the problem.
Daniel J. Starks, St. Jude’s chief executive, said in a telephone interview that the company had hidden nothing. “We’ve been more transparent than others,” he said.
But several experts say they believe the company was slow to warn of the problem with the lead, which is estimated to be implanted in 128,000 patients worldwide.
One of the first investigators to examine the problem, Dr. Ernest W. Lau of Belfast, Northern Ireland, said that he took his concerns about the issue to St. Jude in 2010 and did not think that company officials responded appropriately.
“There should have been more warning,” said Dr. Lau, who is a heart device expert at Royal Victoria Hospital.
Several heart device experts said that the St. Jude incident represented a troubling repeat performance. As with Guidant and Medtronic, the crucial data highlighting the problems with St. Jude’s leads did not come from its own monitoring systems, but from outside researchers. Several experts also said St. Jude appeared to play down the issue’s seriousness.
“They have at multiple steps underplayed the gravity of the situation,” said Dr. Kenneth Ellenbogen, a device expert in Richmond who has consulted for St. Jude and its competitors.
The St. Jude leads at issue involve two models, the Riata and the Riata ST. The company stopped selling both models in late 2010. For the last several years it has been selling a defibrillator lead called the Durata, which it says has an extra coating of insulation that prevents the types of problems affecting the Riata models.
On Friday, St. Jude responded aggressively to its critics. The company contended that a researcher, Dr. Robert G. Hauser of Minneapolis, made several errors that made it appear that the Riata had produced more deaths than another widely used lead made by a competitor, Medtronic.
Mr. Starks and other St. Jude executives have also accused Medtronic of carrying out a whispering campaign suggesting that St. Jude’s new Durata lead is prone to the same types of failures as the Riata.
St. Jude officials also maintained that their reports about product-related problems to a publicly available database run by the F.D.A made their devices look more troubled because St. Jude’s reports were more detailed and complete than those filed by Medtronic.
The company’s stock has fallen sharply over the last week. On Thursday, it fell 1.7 percent to close at $40.97 a share. This week, the company also said it would stop selling two other models of older heart device wires with similar insulation problems.
A spokesman for Medtronic, Christopher Garland, said that St. Jude claims were “false” and that the company filings were extremely thorough. Dr. Hauser, the researcher, said that he was not surprised that St. Jude was disputing his report.
“They have been very contentious” about this, he said.
According to St. Jude officials and experts outside the company, the issues surrounding the Riata involve two separate problems.
Dr. Hauser’s report involved cases where the silicone coating of the defibrillator lead wore away, setting up the potential for a short circuit when the device fires a life-saving jolt.
St. Jude officials have acknowledged that reports show that at least 20 patients have died in such episodes, but say that such incidents are not unique to the Riata and that the rate of the fatal episodes is comparable to that of other devices.
The problem specific to the Riata involves those cases in which the internal wires work their way out of their casing. No deaths have been attributed to that problem and in most cases, those wires continue to function.
But when the wires fail to work they can lead to a variety of electrical malfunctions.
In late 2010, St. Jude sent a letter to doctors alerting them about data showing that the silicone coating of the Riata lead could wear away. However, the letter estimated that the overall rate of abrasion was tiny, just 0.47 percent, and that the exposed wire issue represented just a small fraction of that figure.
But the issue took off nearly a year later with the report of Dr. Lau’s group in Belfast. Rather than simply looking at reports of failures, he and his colleagues began to run diagnostic imaging tests on patients and saw the protruding wires.
Since that report appeared, other researchers have done additional tests and found incidences of wire protrusions running as high as 30 percent. The insulation-related problem appears to develop only after several years of implant and so its scope may accelerate as the devices age.
It is the wide difference between the data reported by outside researchers and the early reports put out by St. Jude that has led some experts, like Dr. Ellenbogen in Richmond, to question why St. Jude did not root out the problem’s scope.
St. Jude officials said they released information about the Riata as it became available and they followed the advice of their outside consultants. The company added that it was now conducting a study of patients with the Riata wire and would provide added guidance to doctors about how to best manage patients.
One of those advisers, Dr. Roger Freedman, said the company had been open and frank with the board and that he had faith in the Durata, St. Jude’s newer lead.
Mr. Starks emphasized Friday that he saw the question raised about the company’s performance as a commercial attack meant to undercut sales of the Durata.
“This has become a topic of competitive marketing,” Mr. Starks said. “We have competitors going to physicians and informing them, either incompletely or mistakenly, of a competitively hostile view of the facts.”
Some doctors say that the Durata’s improved coating may solve the problem and so far, data shows the device is performing.
But Dr. Lau, for one, has already made his decision. “I have stopped implanting Durata,” he said.
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