At least 20 deaths have been linked to problems with the St. Jude Riata ST defibrillator lead, and a recent study found that 24% of large-diameter leads show signs of erosion. The wires that connect the defibrillator to the heart can poke through the silicon insulation, leading to malfunction. A damaged defibrillator lead may fail to shock in an emergency or delivery unnecessary shocks. This can cause severe injury, disability, or death.
October 11, 2012 — Documents collected by the FDA reveal that St. Jude knew about the Riata “inside-out abrasion” issue as early as October 2005, but waited six more years to issue a recall. Click here to read more.
August 17, 2012 — The FDA has published a Safety Communication with two recommendations: Patients with the St. Jude Riata defibrillator lead should undergo chest X-rays to check for signs of externalized wires. Furthermore, St. Jude must conduct a three-year safety study to better understand the rate of failure and other risks associated with the defibrillator lead.
What is the St. Jude Riata Defibrillator Lead?
The St. Jude Riata Defibrillator Lead is a medical device that is used to help people with life-threatening irregular heart rhythm. The device consists of a high-voltage defibrillator, which is connected to the heart by a long wire called a lead. The Riata is designed with silicone insulation around the lead.
During an emergency, the defibrillator can sense major changes in the heart rhythm. It sends a high-voltage shock through the lead and into the heart. An estimated 79,000 Americans have the St. Jude Riata defibrillator leads. The devices are implanted in around 128,000 people worldwide.
What is the problem?
St. Jude warns that small wires in the lead may poke through the silicon insulation. This is a problem, because the exposed wires could become damaged. They may malfunction and fail to deliver a life-saving shock in an emergency.
Unfortunately, it can be very difficult to tell whether the exposed defibrillator leads are still functional, even with regular check-ups. Sometimes, patient death is the only sign that the defibrillator lead has failed. Patients may need to undergo painful high-voltage tests to check the functionality of the lead.
Recall of the St. Jude Riata Defibrillator
On December 21, 2011, the U.S. Food and Drug Administration (FDA) ordered a Class 1 recall of the St. Jude Riata ST defibrillator leads. The recall was due to reports that the silicone insulation around the defibrillator lead could erode away prematurely, and the wires could be exposed. The FDA was concerned that this might lead to deadly device malfunctions.
If the defibrillator were to malfunction, it could deliver an unnecessary electrical shock, or fail to deliver a shock in an emergency.
A Class 1 recall is the FDA’s most serious, urgent type of recall. It is reserved for scenarios when people are at immediate risk of death due to a defective medical device or drug.
St. Jude Riata Linked to 20 Deaths
On March 26, 2012, Heart Rhythm Journal published two studies that were critical of the Riata defibrillator leads. The first study reviewed voluntarily-submitted adverse events, and found 20 deaths attributed to the Riata ST lead failure. The researchers noted that all of the deaths were apparently due to insulation defects, which caused high-voltage short-circuiting.
The second study found that a high percentage of exposed leads had electrical failure. Exposed leads were very common in patients who had the Riata leads for at least five years.
St. Jude has asked the journal to retract these studies, calling them inaccurate and biased, but the journal has refused to oblige.
Studies of St. Jude Riata Defibrillator Leads
Since St. Jude Medical issued a recall in 2011, they have been conducting a safety study to determine how often the Riata defibrillator leads are defective. Preliminary results from the study discovered that 24% of large-diameter leads had inside-out erosion, and 9.4% of small-diameter leads had erosion. When the wires erode into the silicon insulation, they may become less effective or malfunction. The researchers are continuing the study and will have long-term data in two years.
The results of this study are important for the tens of thousands of people who still have a Riata defibrillator lead. Furthermore, St. Jude Medical manufactures other defibrillator leads with a similar design.
Side effects of a defective St. Jude Riata defibrillator lead may include:
- The device may fail to activate in an emergency
- The device may accidentally activate when there is no emergency
- Patient may need to undergo painful high-voltage tests to make sure the device is still working
- Heart damage
- Perforation of the heart tissue