FDA recommends image guidance for implanted heart defibrillators

FDA recommends image guidance for implanted heart defibrillators with St. Jude Medical Riata leads

The U.S. Food and Drug Administration recommended today that patients who have implantable heart defibrillators with Riata and Riata ST leads, manufactured by St. Jude Medical, should have X-rays or other imaging alternatives to check for abnormalities in the insulation surrounding the lead, which is a wire attached to the device that is inserted into the heart.

The manufacturer of the leads, St. Jude Medical, recalled them in November 2011 after reports of premature erosion of the insulation around the electrical conductor wires, also called insulation failure. St. Jude Medical, located in St. Paul, Minn., had stopped selling the leads in late 2010. According to the company, as of 2011, about 79,000 Riata leads remained implanted in patients in the United States.

Riata and Riata ST leads are used to connect an implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) to the heart in order to monitor its rhythms. ICDs and CRT-Ds can detect life-threatening abnormal heart rhythms and deliver an electrical shock to the heart to restore normal heart rhythms. ICD and CRT-D leads typically have layers of insulation surrounding them that protect electrical conductor wires inside the lead.

Insulation failure may cause some of the electrical conductors inside Riata leads to move within or move entirely outside the outer lead insulation. The lead may malfunction and lead to inappropriate or no shock therapy and potentially life-threatening abnormal heart rhythms.

The FDA’s recommendation is supported by several studies that have demonstrated that routine imaging of the leads may detect previously unrecognized abnormalities with the insulation. X-rays or other imaging techniques will help health care providers develop individualized patient treatment plans. The FDA is also cautioning against routine removal of leads without careful evaluation of benefits and risks to the individual patient.

The FDA is also requiring St. Jude Medical to conduct three-year postmarket surveillance studies (or section 522 studies), to collect clinical data related to the potential for premature insulation failure in Riata and Riata ST leads.