All 25,000 Americans who have a potentially faulty pacemaker wire in their chests should undergo special X-rays to see if their wires are among the 12 percent that may break, the government said Tuesday.
Not every wire that breaks will be dangerous, but at least 1.6 percent of patients are at risk of death or serious injury if the wire pops out of its plastic coating and punctures the heart wall, the Food and Drug Administration said.
This is the first advice to patients since problems with the electrical cable, which delivers impulses to keep the heart beating regularly, were made public two weeks ago.
But neither the FDA nor manufacturer Telectronics Pacing Systems Inc. could tell exactly who should undergo the sometimes-risky operation to replace the wire.
“The frequency of fractures is a lot higher than we had understood,” said the FDA’s Dr. Bruce Burlington.
Telectronics’ wire was implanted in some 40,500 patients worldwide between 1987 and last fall, when unused wires were recalled from hospitals.
The J-shaped end attaches to the heart like a fishhook. Inside a plastic coating is a coiled electrical wire, plus a small flat wire that helps the lead keep its shape. When the flat wire moves back and forth, as may happen when people move, it can break. Then the jagged end may pop out.
In at least 110 patients, this protrusion has occurred without consequences. But in the worst cases, the jagged wire cut the heart’s main blood vessel, the aorta, causing two women to bleed to death rapidly.
It also can cut the atrium, the chamber that houses pacemaker wires. In those cases, bleeding can be slow enough for people to seek emergency help; symptoms include fainting, shock and limbs turning blue from lack of circulation.
xxxx Dangerous device At issue is the Accufix atrial “J” pacemaker lead, models 330-801 and 329-701, made by Telectronics of Englewood, Colo.