Saturday, May 12, 2012

Patient Harm: Riata ICD leads unreliable




Agonizing Choices for Heart Patients
Michael W. Minton has a device in his chest that could save his life by helping his heart beat properly. Or not.
A retired factory worker from Joelton, Tenn., Mr. Minton is one of 79,000 U.S. patients implanted with the troubled Riata defibrillator lead from St. Jude Medical Inc. STJ -0.64% The lead, a set of insulated wires, is threaded into the heart and connected to a defibrillator that zaps the heart into normal rhythm. But in a number of cases, the devices' wires are breaking through their insulation.
Doctors say the protruding wires could be a sign of dangerous electrical problems that could cause the lead to malfunction, shocking or even killing the patient.
Mr. Minton is one of those cases, though his device is still working properly, and now he's faced with a decision: Should he have the failure-prone heart device cut out, even though the procedure carries significant risk, or wait and hope that the Riata holds up.
After seeing an X-ray image of his lead that he said looked like an appliance wire stripped of its insulation, Mr. Minton, 58 years old, decided, "I want that thing out."
A small but growing number of patients are starting to agree. At a handful of institutions, including Vanderbilt University Medical Center, Brigham and Women's Hospital and the Minneapolis Heart Institute, doctors are starting to remove even some functioning Riata leads when the devices show signs of wear. So far, Vanderbilt doctors have used X-rays to identify 29 leads with significant insulation problems, and removed one-third of them, beginning with those that are also malfunctioning.
The full scope of the problem is unknown, though by some counts, involving small groups of patients, as many as one-third of Riata's leads have protruding wires. That lack of clear information creates "much uncertainty for physicians, patients and patients' families," wrote a group of U.S. senators in a May 7 letter seeking details of St. Jude's handling of the Riata situation. St. Jude said it is responding to the letter.
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St. Jude's share price plunged 10% after public attention focused on the Riata leads a month ago. The stock fell 25 cents to $38.88 in 4 p.m. trading Friday on the New York Stock Exchange. Heart-rhythm devices, including defibrillators and leads, made up more than 50% of St. Jude's $5.6 billion in 2011 sales.
The procedure to remove leads, which can tear heart tissue or leave broken pieces of the wire inside veins, is controversial. Guidance from St. Jude, which stopped selling Riata-series leads in 2010, recommends against removing the devices before they malfunction, because the risk of complications is considered high. One study of a favored lead-removal technique, in 2010, found a 1.5% chance of major complications, which can include death.
St. Jude said in a statement that its guidelines were devised with help from an independent physician advisory panel. Physician opinions may differ, and clinical decisions in general should be made on a patient-by-patient basis, it said.
The company will release a 700-patient study in June that could offer doctors more information about the risks of leaving leads with insulation flaws in place. Each patient will be X-rayed to look for the protruding wires, a St. Jude spokeswoman said.
The Heart Rhythm Society, a medical group, hasn't advised doctors whether to remove the leads, and is awaiting further data. Its president, the Cleveland Clinic's Bruce L. Wilkoff said he has removed some leads that didn't have electrical problems.
Defibrillator leads are often bound to the walls of veins and the heart by scar tissue, an obstacle that worsens with time. To remove them, doctors slide sheaths over the wires and scrape the scar tissue away, freeing the lead. The tip of the wires can become anchored in the heart wall, and removing them can tear a hole.
At Vanderbilt, Mr. Minton's doctor, Christopher R. Ellis, said his group decided to recommend to patients the removal of all leads with frayed wires visible on X-rays, even if they work.
Dr. Ellis acknowledged that the Vanderbilt approach is aggressive, but he said the group's rate of complications appears lower than the risk of Riata problems. "I don't see anything good that can happen from leaving all these leads in," he said.
Riata was recalled in December after St. Jude's medical advisers noted a higher-than-normal rate of an insulation failure, called externalization. The leads are also prone to other types of failures, and in March a study linked the devices to 20 deaths caused by short circuits. Not all externalized leads also short circuit, but new data suggests it is a sign of the problem.
In research presented Thursday at a Heart Rhythm Society meeting in Boston, 110 patients at seven hospitals who were checked with X-rays showed a 25% rate of externalized leads. Nearly one-third of those leads also had electrical problems, said Raed Abdelhadi, a Minneapolis Heart Institue doctor who presented the finding. Vanderbilt contributed to the study.
If future studies confirm those problem rates, Dr. Abdelhadi said, "If I were a patient, I'd know what I'd want."
Doctors should await additional data, said Raymond H.M. Schaerf, a Burbank, Calif., surgeon who removes leads, but who has counseled his patients against extractions when leads are functioning properly.
"When doctors get over aggressive, patients suffer more from the extraction than the actual lead," Dr. Schaerf said.
In previous recalls, such as the 2007 recall of Medtronic Inc.'s MDT -1.02% Sprint Fidelis lead, more patients were harmed by overzealous doctors than faulty leads, he said. It is not yet clear how Riata will compare with Fidelis, he said.
Laurence Epstein, chief of cardiac arrhythmia at Brigham and Women's Hospital in Boston, said that because the true risks of Riata are unclear, he leaves the choice up to his patients. After seeing loose wires in their hearts in X-ray images, some choose the extraction, Dr. Epstein said. "People don't like that time-bomb thing," he said.
"If it is externalized, in my mind, the lead has failed," said Dr. Epstein, who like others called for more data to gauge the risk.By nature, Mr. Minton, Dr. Ellis's patient, said he was inclined to deal with his Riata problem upfront, even if the procedure brings its own risks. "I'm not the type to stand in the closet for a couple of hours because there is a tornado warning," he said.
Write to Christopher Weaver at christopher.weaver@wsj.com
A version of this article appeared May 12, 2012, on page B1 in some U.S. editions of The Wall Street Journal, with the headline: Agonizing Choices for Heart Patients.
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