August 17, 2012 — In a new Safety Communication published by the U.S. Food and Drug Administration (FDA), the agency is recommending that people who have the St. Jude Riata defibrillator lead should have an X-ray to check for problems with the lead. Furthermore, the FDA is also requiring a three-year post-marketing surveillance study for the Riata ST Optim, QuickFlex, QuickSite, and Durata ICD leads.
In the new studies, the FDA is asking St. Jude to find out how many patients have leads with insulation failure, whether a chest X-ray detected the failure, how quickly the insulation fails, how quickly malfunctions occur, and the adverse events that occur during treatment for defective leads.
St. Jude has already recalled four types of defibrillator leads. The Riata and Riata ST were recalled in November 2011. In April 2012, St. Jude recalled the QuickFlex and QuickSite leads. The Durata has not been recalled and St. Jude has defended the safety of this device.
The problem with the leads is that the insulation around the electrical wire can erode, which allows the wire to protrude outside the insulation. There is a small risk that the wire may deliver an unnecessary shock, or fail to deliver a shock in an emergency. Externalized wires do not always malfunction, because they have their own insulation. It can be difficult to determine whether the externalized wire is defective until an adverse event occurs.
Although defibrillator leads are supposed to last for at least ten years, the FDA is aware of an increase in Riata lead failures after only four years.
This is why the FDA is recommending imaging tests for people who have the Riata defibrillator leads — approximately 80,000 people in the United States, and 130,000 worldwide. The agency is recommending either a chest X-ray or fluoroscopy, and physicians should work closely with radiologists because defects can be hard to see.
The FDA is not recommending routine removal of the Riata defibrillator leads. Extraction surgery comes with a significant risk of injury or death, especially for people who have had the lead for many years. Therefore, physicians should only consider removing the Riata lead if visual abnormalities are identified, and voltage tests are also abnormal.
For people who have insulation failure, the FDA is recommending routine X-rays to monitor the progression of the problem.
The Safety Communication comes one month after St. Jude released phase-one results of the Riata Lead Evaluation Study. They found that insulation failure occurred in 24% of people with large-diameter Riata leads, and in 9.3% of small-diameter Riata leads. This means that it is possible that there are thousands of people who have insulation failure and are at risk of serious injury.