TAMPA — In 2005, Kevin Fountain had surgery intended to ease fears that his damaged heart might beat irregularly.
Surgeons implanted in his chest a cellphone-sized device to deliver a shock and correct the problem. But late last year that defibrillator — specifically, the lead that connects it to his heart — became a source of anxiety, not reassurance.
The 53-year-old Tampa man is among patients told they might have a defective lead in their chests. The news left them with more questions than answers.
"It looked kind of funny," Fountain recalled of seeing his defibrillator on an imaging scan. "I could see the wires sticking out."
His wife reacted more strongly.
"My thought was, 'Oh my God,' " said Carol Johnson, 44. "You put it in to save people's lives and then it's coming apart."
Fountain's lead was made by St. Jude Medical, and is known as the Riata. According to the company, the Riata was placed in 128,000 heart patients, children and adults, worldwide between 2001 and 2010. In 2010, the company voluntarily stopped making it after numerous reports of externalization — when the lead's outer covering breaks down, exposing interior wires and giving the frayed appearance Fountain saw.
St. Jude estimates that 24 percent of its larger Riata leads and 9 percent of its smaller leads developed the problem.
In 2011, the U.S. Food and Drug Administration recommended that all patients with a Riata be screened, though St. Jude advised against it because it wasn't clear that externalization was dangerous and might lead people to unnecessarily undergo removal surgery. Removal can be difficult and carries its own dangers.
The problem is being studied by the company and independent researchers. A large group of physicians met in January at a summit organized by the Mayo Clinic and the Minneapolis Heart Institute to share information. But in the meantime there's no clear protocol to follow.
Sanders Chae is a USF Health cardiac electrophysiologist, a physician who specializes in implanted electrical devices for the heart. Fountain is among his patients facing this decision.
"With the Riata, there's no clear data to show the exposed wires are harmful, so it's unclear what the effect can be," said Chae. "It's unclear what to do."
Patients face questions their specialists can't answer fully. Do they get screened to see if the lead is damaged? Do they have it removed whether or not damage is seen? Do they leave it in place and hope that careful monitoring by their doctor will catch a problem before it kills them?
Adding to the worry: In some patients, the Riata replaced another lead, made by the Medtronic Corp., that failed, in some cases misfiring and shocking patients.
In a letter to patients posted on the company website, St. Jude says even if the outer layer is frayed, the lead will still do its job. It analyzed faulty leads removed from patients and found 87 percent had no electrical problems. The rest had electrical abnormalities but only 2 percent were caused by externalization.
"The (exposed wires or) conductors have another layer of insulation on them, it's not bare wire. They are still insulated and perform normally in the majority of cases," said Dr. Mark Carlson, a cardiac electrophysiologist with St. Jude Medical.
The company says no one has died as a result of lead failure or malfunction but there were two deaths and one serious injury associated with removal of externalized leads.
But published studies suggest Riata leads may be more dangerous than the company says.
"Whether Riata leads with externalized conductors truly perform normally is not known,'' said Vanderbilt University electrophysiologist Christopher R. Ellis, who was among the experts at the Minneapolis summit. He pointed to a study published just last month in the journal Heart Rhythm that "sheds doubt on long term Riata performance.''
Chae says most of his patients who have the Riata want it removed.
Dr. James Irwin, a cardiac electrophysiologist at St Joseph's Hospital in Tampa, has one patient with a Riata she received elsewhere that shows signs of externalization, but she has another illness that makes surgery even more dangerous.
Otherwise, he said, "I would recommend removal,'' said Irwin, who has never used the Riata. "We look at what leads last longer and, if they fail, how difficult it is to remove. The Riata is more difficult to remove. So, I never used it for that reason."
Chae and his USF colleagues have seen an increase in patients seeking removal or guidance on what to do. The longer a lead is in place, the more scar tissue forms, and the tougher it can be to remove.
With his battery due for replacement soon, Fountain elected to have his defibrillator and faulty lead changed in December. His wife insisted.
"He thought I was over-reacting but, it was scary for me," said Johnson, "If it would have stopped working and something happened with his heart, then what?
Irene Maher can be reached at firstname.lastname@example.org.