Updated
April 9, 2012, 8:09 p.m. ET
FDA in Hot Seat on Safety
Doctors Want Agency to Better Gauge
Risks of Heart Devices
Doctors are pushing the FDA to
strengthen safety-reporting requirements for medical devices after a spate of
faulty heart-defibrillator wires has caused injuries and deaths in patients.
Tom Burton has details on The News Hub. Photo: Reuters
Doctors are pushing the Food and Drug Administration to strengthen
safety reporting requirements for medical devices after a spate of faulty
heart-defibrillator wires has caused injuries and deaths in patients.
The FDA this month plans to unveil a more rigorous safety-monitoring
program that could more quickly remove faulty devices from the market. Among
the agency's ideas is to assign each medical device a unique number that will
make it easier to track device malfunctions. The pressure from physicians comes
after new evidence released last month showed a defibrillator wire made by St. Jude Medical Inc. was linked to 20 deaths.
Faulty Wires
Recent failures of wires, or leads, used in heart devices:
Oct.
2007 Medtronic's Sprint Fidelis lead pulled from market because of
fractures
Dec.
2010 St. Jude stops selling Riata, Riata ST, describing rare 'lead
abrasions'
Dec.
2011 FDA announces recall on Riata, Riata ST leads
March
2012 Medical journal report links Riata, Riata ST to 20 deaths
Sources: St. Jude Medical, Medtronic;
WSJ reporting
Doctors say the FDA's current system has failed to gauge the risks of
faulty heart-defibrillator wires, and they want the FDA to ensure that
hospitals report when such devices malfunction. Under the current system,
federal requirements call for hospitals to report when these devices fail, but
they don't uniformly do so, doctors say. Instead, the agency relies extensively
on voluntary reports from a few hundred hospitals.
"We don't know the numerator of device failures at all," said
Edward J. Schloss, medical director of cardiac electrophysiology at Christ
Hospital in Cincinnati. "There are times a lead fails, and no one knows it
failed."
Robert G. Hauser, a prominent cardiologist at the Minneapolis Heart
Institute, said, the story of the St. Jude wires "is another example of
our flawed regulatory system." He has been highly critical of what he
regards as passive FDA surveillance of medical devices.
"We would concur that the current efforts are not constructed to
identify underperforming products in the marketplace," said William
Maisel, deputy director for science with the FDA's center for medical devices.
"We need a robust data-collection methodology."
Implantable defibrillators, invented over 30 years ago, are used to
correct faulty heartbeats that can be lethal. They are surgically placed under
the skin in the shoulder area and connected by a wire called a "lead"
to the heart. The apparatus is designed to dispatch a powerful jolt to the
heart—similar to sticking a knife in a light socket—that corrects the heartbeat.
If the device doesn't do that when needed, or sends the jolt to the heart when
not needed, the result can be death.
The leads are susceptible to damage because the heart's regular pounding
can stress a lead over time and, in rare instances, cause it to fail. In 2007, Medtronic Inc. pulled from the market a brand of
wire that sometimes fractured and has been linked to at least 13 deaths out of
more than 200,000 implanted.
The problem got fresh attention last month when the cardiac-medical
journal Heart Rhythm reported that St. Jude Medical's Riata and Riata ST heart
wires, which are still implanted in 79,000 U.S. patients, had been linked to 20
deaths.
To track safety problems with medical devices, the FDA relies in large
part on a safety program in which about 300 hospitals voluntarily report when
devices malfunction. Since that system isn't mandatory, it is difficult for the
FDA to get an early handle on how frequently a device is failing and how
urgently to warn patients and doctors, heart specialists say.
The FDA's Dr. Maisel said the agency queried hospitals in the voluntary
program in 2008 about defibrillator leads, including St. Jude's Riata, but that
"there was not a specific signal" that Riata had safety problems.
The FDA also has a database of "adverse-event" reports about
devices, deaths and serious injuries. That is where the number of deaths
related to Riata malfunctions appears. Because hospitals don't consistently
report these events, the database doesn't accurately reflect which wires are
tied to more safety problems than others.
FDA officials say that assigning each device a number could enable the
agency to link to billing and medical records to better track faulty devices.
"The ability of the unique device identifier number to strengthen our
post-market surveillance is enormous," says Peper Long, associate director
for external relations at the FDA's medical-device center.
In the case of St. Jude Medical's Riata wires, various doctors say 15%
of the devices have experienced mechanical failures. One such report came from
Royal Victoria Hospital in Belfast, Northern Ireland. In that study 165
patients were screened and 25 were found to have the malfunction.
St. Jude Medical said it is evaluating these reports. These failure
percentages measure the rates at which some Riata leads push through their
silicone outer coating and become exposed inside the body. In most cases, this
malfunction doesn't injure or kill patients, partly because the leads have a
second coating that often remains intact.
Mark Carlson, St. Jude's medical director, said that in the cases of
wires pushing through insulation, "there have been no reports of failure
to pace or unwarranted shock." He said the company began a clinical trial
in December 2011 to study the extent of the malfunction. St. Jude has created
registries involving more than 10,000 patients for the defibrillator leads it
currently markets, and the company says that these should provide better and
earlier insights on leads' performance.
The company says it believes Riata and Riata ST's performance is
comparable to that of other defibrillator leads that were on the market in the
past decade, and recommends against having patients get their leads surgically
removed.
St. Jude began selling the Riata in 2002 and the Riata ST in 2005. By
2010, the company took the devices off the market, and a year later issued an
advisory about instances of wires pushing through their cables.
Write to Thomas M. Burton at tom.burton@wsj.com
A version of this article appeared April 10, 2012, on
page B1 in some U.S. editions of The Wall Street Journal, with the headline:
FDA in Hot Seat on Safety.
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