A top cardiologist is of the opionion that a Durata lead failure report is, in fact, credible. We recently wrote that the U.S. Food & Drug Administration (FDA) received a report of a St. Jude Durata cardiac defibrillator lead wire breaking free of its insulation, a potentially dangerous and life-threatening defect that has led to the demise of another St. Jude defibrillator lead model.
St. Jude’s public disclosure of the report was followed by a six-percent share drop this week. Apparently, the lead conductor became externalized, which enabled the defibrillator’s electricity-carrying wire to become exposed through its insulation, said Reuters. The Durata is designed to connect an implanted cardiac defibrillator to the heart and delivers life-saving jolts that either keep a heart beating or regulate heart rhythm. St. Jude shares remain down eight-percent from prior trading levels.
St. Jude lead safety has been the focus of controversy ever since a respected medical journal published an article by Dr. Robert Hauser that reviewed St. Jude’s Riata lead, said Reuters. The study’s results linked its Riata leads to more patient deaths than St. Jude first thought and found that it tried to present in-house data on the Riata’s safety, said Reuters. Dr. Hauser, an electrophysiologist at the Minneapolis Heart Institute Foundation, told Reuters that he believes the FDA report is genuine, that industry may have made too much of it, but that, “The impact is probably going to be greater than what this case actually represents.”
As we’ve written, St. Jude introduced the Durata lead after its previous device, the Riata, was failing. The Riata was removed from the market in 2010 following numerous defect reports and links to high failure rates. Specifically, reports of the Riata’s conductive ends breaking free and either not delivering shocks at the right time or failing to deliver shocks were received. The exposed ends have also been linked to internal injuries, including lacerations. An inferior housing on the Riata leads was eventually blamed for the large number of reported defects and it was changed to a silicone material known as Optim and released as the Durata lead.
Media reports indicate that a physician anonymously reported the defect to the FDA and not St. Jude Medical Inc. on April 17. Although the means by which this defect was reported is being questioned by some. If confirmed as fact, the report would be the first known event in which a conductive end on a Durata lead wire had broken free of its silicone housing, exposing the wire it contains.
St. Jude was not notified of the adverse event report until it appeared on FDA’s Maude database, according to a prior Bloomberg report. Experts interviewed by the source say it is rare for an adverse event report with as many specific details as contained in this one to be submitted in this means; the FDA and St. Jude are both investigating. The physician’s report to the database reportedly did not include details such as the device serial number or physician and hospital names. An analyst told Bloomberg that although this was an isolated incident, more Durata failure reports could indicate deficiencies with thinner cardiac defibrillator leads, versus older models not linked with similar adverse event complaints.
Hauser said that a number of studies are in the works, but none are expected to be completed before year-end, wrote Reuters. “When questions are raised, you need to do more work and gather more data,” he said.