The U.S. Food and Drug Administration recommends that patients with Riata or Riata ST heart defibrillator implants have X-rays or other scans to check for abnormalities in the lead insulation. The manufacturer, St. Jude Medical of Minnesota, recalled the leads in November 2011 due to premature erosion of the insulation around the electrical conductor wires. The company says about 79,000 Riata leads remain in patients nationwide.
An insulation failure might cause the Riata leads to shift, which could lead to inappropriate or no shock therapy and potentially fatal abnormal heart rhythms, according to the FDA. Some studies have shown that routine imaging of the leads could detect insulation abnormalities. The FDA said removing the leads might not be necessary and has ordered St. Jude Medical to conduct follow-up research.
“The majority of Riata and Riata ST leads, including those that show signs of electrical conductor migration or externalization, continue to function normally and provide life-saving support for patients,” said Dr. Jeffrey Shuren, director of FDA's Center for Devices and Radiological Health. “However, the agency does not have enough information to determine the frequency and timing of insulation failure in these leads; therefore, the postmarket surveillance studies will ensure that health care professionals and patients get the data they need to better guide clinical management decisions.”