A recent study found that the St. Jude Durata defibrillator lead is associated with dozens of adverse events and one death. The research found that the Durata can abrade and erode — similar to the defect that caused St. Jude to recall the Riata defibrillator lead in 2011. The U.S. Food and Drug Administration (FDA) has recently asked St. Jude to conduct a new study of the Durata to better understand its risks and safety.
What is the St. Jude Durata Defibrillator Lead?
The St. Jude Durata lead is a defibrillator component manufactured by St. Jude Medical. The Durata was introduced after St. Jude was forced to recall Riata defibrillator leads in November 2011 due to defects with the lead insulation. St. Jude developed the Optim coating, which the company claimed was safer and more durable than the coating on the Riata leads. The U.S. Food and Drug Administration (FDA) approved Durata coated with Optim insulation in 2007.
A defibrillator is a medical device that monitors a patient’s heart rhythm and delivers a high-voltage shock if an arrhythmia occurs. The defibrillator is located outside the heart, and it is connected to the heart tissue with a long, thin wire called a lead. The lead transmits data from the heart to the defibrillator. The lead also carries a high-voltage shock during an emergency.
Problems with the St. Jude Durata
Unfortunately, new research suggests that the St. Jude Durata could be defective, though more studies are needed to understand this link. St. Jude recalled the Riata in 2011 due to inside-out erosion (caused by the inner conductor wire pushing against the outer insulation until it eventually externalized). There are only a few reported instances of this occurring with the Durata defibrillator lead. More commonly, the Durata fails because of outside-in abrasion (when the lead abrades against other devices in the body).
The problem with a damaged defibrillator lead is that it can malfunction — it may deliver unnecessary shocks, or fail to deliver a shock during an emergency. Treatment for a damaged defibrillator lead is very complex. Not all damaged leads are defective. Determining whether the lead is defective can be very difficult, unless a serious adverse event occurs. Surgery to remove the damaged lead has a high risk of injury or death.
Study Links St. Jude Durata to Injuries, Death
A recent study has linked the St. Jude Durata to dozens of adverse events and one death. The study, published by Dr. Robert G. Hauser in Heart Rhythm Journal in August 2012, linked the Durata to 37 adverse events reported to the FDA’s public database. Because these are voluntary reports, the actual number of incidents may be higher.
Dr. Hauser found the following results:
- 32% failed due to can abrasion, which occurs when the lead abrades against the pulse generator
- 6% failed to due friction abrasions, usually by rubbing against another device in the body
- 72% of the damaged leads had electrical abnormalities
- In 3 cases, the malfunction could have been caused by friction, but the cause was not listed in the report
- In another 3 cases, “inside-out” erosion was identified. This is significant, because this is the type of defect that sparked the Riata defibrillator lead recall.
Dr. Hauser concluded,
The results of this study suggest that Optim … does not prevent critical insulation failures in Riata ST Optim and Durata leads that are caused by friction with the can or another device. Of equal concern is the fact that these failures occurred in leads that had only been implanted for ~4 years or less.
He recommended that cardiologists should wait until more long-term studies are conducted before implanting more of these devices, because the adverse events are an early warning sign that there could be problems with the Durata defibrillator lead. The FDA has recently asked St. Jude to conduct a three-year safety study of the Durata defibrillator leads.