If you were injured by a defective St. Jude Riata defibrillator lead, you are not alone. A recent study has found that 24% of large-diameter Riata leads can erode into the silicon insulation. In some cases, the wires can protrude outside the lead. This increases the risk of device malfunction — it could deliver an unnecessary shock, or fail to deliver a shock in an emergency. It may also be very difficult to determine whether the defective St. Jude Riata lead is malfunctioning until the patient has an adverse event.
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 ST Defibrillator Lead is a part of a defibrillator, which is a device that is implanted into the heart to treat deadly cardiac arrhythmia. The leads are long, thin wires that connect the defibrillator device to heart tissue. They are responsible for monitoring and regulating a patient’s heart rhythm. When the heart has a serious abnormal rhythm, the device delivers a high-voltage to restore normal heart rhythm.
An estimated 79,000 people have been implanted with these devices in the U.S. alone, with about 128,000 Riata leads implanted worldwide.
What is the problem?
According to the manufacturer, the St. Jude Riata defibrillator leads can fail when the conductor cables wear through the silicone insulation. This can cause the cables to protrude outside the lead. Because the conductors themselves are coated with a Teflon-like insulator, they may remain functional despite being outside the insulation. However, it may be very difficult to tell whether the lead is functional until the patient has an adverse event.
St. Jude Medical first notified physicians of the problem in a letter sent on December 15, 2010. However, the company and the FDA did not issue a recall for another year, nor did they order any clinical studies to answer critical questions about the safety of the device.
The first manifestation of failure of Riata/Riata ST leads may be patient death. This is because it is very difficult to detect high-voltage lead dysfunction. Even with frequent check-ups and monitoring, the dysfunctional lead may only be diagnosed when its failure causes patient death.
Recall of the St. Jude Riata Defibrillator
December 21, 2011: The U.S. Food and Drug Administration (FDA) issued a Class I recall of the Riata ST silicone endocardial defibrillation leads, due to the risk that the silicone insulation around the defibrillation leads could prematurely erode. When erosion occurs, the metal conductor wires inside the lead can pop out.
Leads with externalized conductors may malfunction. They could potentially deliver an electrical shock when there is no emergency, or fail to deliver a shock during an emergency. This could cause severe injury, disability, or death.
The FDA’s Class I recall is the most serious type of recall. Class I recalls are reserved for devices with life-threatening defects.
St. Jude Riata Linked to 20 Deaths
- This study, published in March 2012 in the Heart Rhythm Journal, found that there were 20 deaths linked to the Riata ST lead failure. All of the deaths appear to be caused by insulation defects that caused short-circuiting between high-voltage components.
- This study, also published in March 2012 in the Heart Rhythm Journal, found that 33% of patients had external leads. Furthermore, leads that had been implanted for at least five years had a high rate of externalized cables.
St. Jude has sought the retraction of these studies, saying they are inaccurate and biased.
Studies of St. Jude Riata Defibrillator Leads
On July 17, 2012, St. Jude Medical announced the conclusion of its own study of the Riata defibrillator leads. They found that 24% of the large-diameter leads have inside-out erosion. This is compared with 9.3% of the small-diameter Riata defibrillator leads. St. Jude is currently conducting long-term safety studies that will go on for the next two years.
St. Jude Riata Defibrillator Side Effects
- Short circuiting
- Failure of the device to activate in an emergency
- Delivery of painful, unnecessary shock
- Patient must undergo high-voltage tests to check lead function
- Heart damage
- Perforation of heart tissue