Overview: A new study is raising concerns once again over heart defibrillator components manufactured by St. Jude Medical. According to a report in the New York Times, a Medtronic-funded study shows that the insulating material used to coat the wires, or leads, in implantable cardiac defibrillator degrades. The issue can cause the defibrillator to malfunction, failing to function when a life-saving shock is needed.
- A Medtronic study shows that the insulating material used in its Durata lead, Optim, lost substantial strength when exposed to series of tests
- The degradation of the insulating material leads to exposed wires (leads), which can lead to an electrical failure and short circuits
- St. Jude recalled the Riata last year because of the risk of exposed wires
Manufacturer: St. Jude Medical
Side Effects & Complications
- Electrical short-circuit
- Software problems
- Increased pacing rate
Study Analyzes Failure of Optim, Durata Insulator
The study was published in the November issue of Macromolecules, a scientific journal published by the American Chemical Society. Researchers compared Optim, the insulating material used in Durata leads, to another material known as Pursil 35. Optim and Pursil 35 were exposed to a series of tests intended to speed their aging. Dr. Frank S. Bates, a University of Minnesota professor who was involved in the study, said that both insulating materials lost significant strength following the tests, although Pursil 35 changed faster than Optim. Medtronic cancelled the development of a device that would have used Pursil 35, a Medtronic spokesperson said.
St. Jude has continued to defend the safety of Durata, despite growing evidence that the lead may have issues similar to its recalled Riata and insists that the lead is safe.
St. Jude Criticized over Defibrillator Leads
Earlier this year, St. Jude took issue with Dr. Robert G. Hauser, a heart specialist who published a study attributing a number of deaths to the defects of the Riata. St. Jude executive Daniel J. Starks attempted to have the study retracted from Heart Rhythm journal, but they refused. The most recent study fuels fears that the Durata has the same defect as its predecessor. Lawrence Biegelsen of Wells Fargo Securities wrote in a note to investors that “It’s becoming increasingly difficult to defend Durata” as he downgraded St. Jude’s stock status from buy to hold.
Last week, the U.S. Food and Drug Administration (FDA) released a report that found issues with the way the company tested Durata for safety. The report caused St. Jude’s stock to fall 12 percent, to a three-year low of $31.37 a share.