Implantable Defibrillator Problems Devolve Into a Blame Game
For some people with heart rhythm abnormalities, an implantable cardiac defibrillator (ICD) can be a lifesaver. The small, electronic device is surgically implanted inside the chest to prevent cardiac arrest from hearts that beat abnormally fast (“tachycardia”). An ICD monitors the heart rhythm, and if it senses tachycardia, it delivers an electrical shock to restore the rhythm to normal.
The devices, which are a couple of inches in size, include cable-enclosed wires, or leads, that connect to the heart. As we recently reported, such defibrillators represented nearly 1 in 3 recalled medical products from 2005 through 2009, and a 2006 study linked defibrillator failure to more than 300 deaths over a 10-year period.
A story in The New York Times earlier this month focused on one manufacturer of ICDs with an unacceptable number of adverse events. The Riata wires in devices made by St. Jude Medical have a tendency to work their way out of the cable coating, causing the device to fire wildly. That’s life threatening to anyone who hosts such a device.
“St. Jude officials have acknowledged that reports show that at least 20 patients have died in such episodes,” The Times reported, “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.”
As The Times noted, last year researchers reported that among patients tested, wires protruded out of 15 in 100 St. Jude leads. As doctors and the medical device industry grapple with the scope of the problem, worry only intensifies because the wires are dangerous to remove, and potentially dangerous to leave implanted.
Three highly visible lead episodes in the last seven years, according to The Times, have raised questions about the FDA’s scrutiny of heart devices. St. Jude’s primary competitors-Guidant/Boston Scientific and Medtronic-have also experienced patient injury or death with their flawed products.
Despite pronouncements by St. Jude executives that it has warned doctors about problems with its leads, medical experts say the company was slow to inform doctors of the 128,000 patients with its device. Giving credence to that claim is the fact that the adverse events associated with St. Jude’s leads were not discovered by its own monitoring system, but by outside researchers
St. Jude took both the Riata and the Riata ST models off the market in late 2010. It continues to sell the Durata, which features extra insulation to keep the wires confined.
The medical journal Heart Rhythm published the article by Dr. Robert Hauser of the Minneapolis Heart Institute Foundation about deaths associated with the Riata lead. St. Jude objected, claiming that it contained several errors, and has called for a retraction.
Company executives said Medtronic was just as culpable, if not more, than St. Jude because it also produced flawed products and intimated that Durata also carried risks of failure. They said Riata looked worse than competitors only because St. Jude had been more complete in filing reports to the FDA than Medtronic.
As Global Data, a research and analysis concern, described it, “The gloves are off and the fight has begun. St. Jude … must defend its honor against a report … [that] compared 71 deaths associated with St. Jude’s Riata and 62 associated with Medtronic’s Quattro Secure, a competing product. Of the Riata deaths, 22 out of 71 were identified as resulting from lead failure as compared to 5 out 62 Quattro Secure deaths. The study suggests that unlike the Medtronic leads, the St. Jude Riata lead deaths were caused by electrical malfunction at high voltages. This differs from the previous conclusion that externalized cables (lead wires coming out of their insulation) were the culprit.”
Merrell Goozner, writing on GoozNews, offered additional perspective on the subject last week. When St. Jude Medical accused Hauser of undercounting the deaths associated with rival devices, he wondered why the phrase “falling out among thieves” came to mind.
“St. Jude and Medtronic are not thieves, of course,” he wrote. “They merely take advantage of a flawed Food and Drug Administration process for approving new devices, where updated devices can enter the market without extensive clinical trial testing because they are only minor variations from earlier technology. When the ‘minor’ variation turns out to be flawed electronic leads that cause the device to repeatedly misfire, leading to the equivalent of a mule kicking the nonpatient in the chest, … then perhaps we have a problem with our regulatory system.”
Goozner, who noted that Hauser also has written about the regulatory mess in the New England Journal of Medicine, examined who supports the Minneapolis Heart Institute. Medtronic, he wrote, has given more than $1 million to the organization and St. Jude/ Boston Scientific have given as much as $999,999. The trial lawyers who sued Medtronic also gave more than $1 million.
“So here I think we have finally found the solution to the vexing conflict-of-interest problem,” Goozner concluded. “Rather than banning people with conflicts of interest from writing editorials and commentaries in leading medical journals (which, if properly reported, might have caused NEJM editors to pause before letting Dr. Hauser write his piece), editors should simply insist that they take money from everyone. It clearly hasn’t dissuaded Dr. Hauser from doing yeomanlike work on behalf of the public health and safety, for which he is to be congratulated.”
This corporate spitting match ignores the overarching concern: What if you’re an ICD patient?
St. Jude says it’s conducting a study of patients with the Riata lead, and will advise doctors how to manage such patients. That’s nice, but it’s not enough.
A story late last week in the Wall Street Journal said that the FDA, pushed by doctors to strengthen safety reporting requirements for medical devices, is planning to introduce a safety-monitoring program whose purpose is to remove faulty devices from the market quickly. Supposedly, the plan assigns each medical device a unique number to enable tracking its malfunctions.
Let’s hope that happens. In the meantime, if you have an ICD, find out if its among the ones detailed above; if so, your cardiologist should be able to address your concerns. If you’re not satisfied, seek a second opinion. Keep the FDA MedWatch program apprised of any problems you have. If you wish to research voluntary reports made to the Manufacturer and User Facility Device Experience (MAUDE) database consulted by the Heart Rhythm researchers, link here.