St. Jude Medical first learned of potential problems with its Riata pacemaker lead in 2005, 6 years ahead of its recall of the medical devices, the Wall Street Journal reports.
The Riata leads, which deliver rhythm-restoring shocks to heart muscles, are prone to so-called "inside-out" abrasion, in which the wires wear through their insulation and can extrude into the blood vessel that carries them. That creates a risk of malfunction or unintended shocks; some 80,000 patients are estimated to have the Riata leads, from about 120,000 sold before they were pulled from the shelves.
But St. Jude first received reports of inside-out abrasion with Riata leads in October 2005, according to the Journal, with an internal probe concluding in 2008 that the medical devices had "potentially serious insulation problems including inside-out abrasion," the newspaper reported. More than 13,000 patients have been implanted with Riata leads since July 2008.