Riata and Riata ST Silicone cardiac leads

Update

Consumers and health professionals are advised that the TGA is aware that the US Food and Drug Administration has recently published information regarding Riata and Riata ST Silicone cardiac leads.

The TGA has reviewed this information and consulted with the Cardiac Society of Australia and New Zealand regarding this issue.

Information and patient management recommendations previously issued by St Jude Medical and published by the TGA below are unchanged, particularly with regard to recommendations for interventional cardiologists.

The Cardiac Society has also published advice regarding management of Riata leads at time of generator change on its website.

Update

26 November 2013

St Jude Medical has released updated data about Riata and Riata ST silicone cardiac leads. 

The November 2013 edition of the TGA's Medical Devices Safety Update includes the latest information about the ongoing evaluation of these leads. 

The findings of this evaluation have not changed the information or patient management recommendations previously issued by St Jude Medical and published by the TGA below.

Riata and Riata ST Silicone cardiac leads - increased wear

17 May 2012

The TGA advises patients and health care professionals of potential problems with the above models of Riata and Riata ST Silicone cardiac leads (manufactured by St Jude Medical) for implantable cardiac cardioverter-defibrillators (ICDs). 

This advisory does not apply to Riata ST Optim leads.

In view of the relatively low failure rate and the risks associated with surgery to replace the implanted leads, routine removal of these leads is not recommended in the absence of evidence of a fault. However, all patients with an ICD using Riata or Riata ST Silicone leads should make an appointment with their cardiologist in response to this alert.

The supply of these particular leads was discontinued in Australia in December 2010. These devices have been cancelled from the Australian Register of Therapeutic Goods (ARTG). Any Riata leads implanted after this date would be of another type and are not affected by this advisory.

TGA is continuing to investigate the reports associated with the failure of the Riata and Riata ST Silicone leads.

Potential problems

There are three potential ways that ICDs connected to these leads may operate incorrectly:

1. the ICD may deliver additional electrical charges when they are not required by the patient;
2. the ICD may not operate when required; or
3. may not provide effective therapy.

These potential problems can be caused by the leads becoming exposed by two different wear patterns:

1. Externalisation (extrusion) of the conductor outside the implanted lead; or
2. Wear (abrasion) to the insulation surrounding the lead.

Information for consumers

If you have an implanted ICD:

• Check the patient identification card provided to you by your implanting surgeon for the model number and implantation date of your ICD cardiac leads to determine whether you are affected by this safety advisory. This issue only affects St. Jude Medical's Riata and Riata ST Silicone leads (model numbers listed above) implanted until December 2010. If you have lost your information card, contact the implanting surgeon or your cardiologist to identify whether you have a Riata cardiac lead affected by this advisory.

If your ICD has Riata or Riata ST Silicone leads connected:

• Make an appointment with your cardiologist. When making the appointment, explain that you are responding to this safety notification.
• Ensure you attend regular follow-up appointments with your cardiologist.
• If you experience any untoward side effects from your ICD, contact your cardiologist immediately or go to a hospital emergency department.
• Routine removal of these leads is not recommended and further management should be discussed with your implanting cardiologist.

Patients with any ICD should carry their identification card with them at all times. If you have any concerns, regardless of the type of defibrillator leads you have, contact a health professional, preferably the cardiologist who implanted the device.

Information for interventional cardiologists

St Jude Medical (the manufacturer), has advised that:

• Patients with an affected lead should be reviewed and the device interrogated. St Jude Medical has recommended individual patient assessment.
• Ongoing regular monitoring at least every three months should continue, in accordance with product labelling. Particular attention should be directed to diagnostic information related to defibrillation lead performance, and any significant changes from the patient’s previous follow-up visits should be sought.
• If there is evidence of a lead electrical failure, manage the patient as per standard practice. This may include x-ray or fluoroscopy.
• Prophylactic replacement of the Riata and Riata ST Silicone leads is not recommended as explantation of any cardiac lead carries significant risk.
• Clinical decisions in this setting should be individualised based on specific patient conditions and circumstances.

St Jude Medical has written to implanting surgeons/cardiologists and hospitals where the implantations were undertaken. A copy of St. Jude Medical's hazard alert communication, which contains additional information, follows.

• St. Jude Medical Australia Pty Limited - Hazard Alert (pdf,125kb) 

Information for all health professionals

Patients with an ICD using Riata or Riata ST Silicone leads should be referred to a cardiologist, preferably the implanting cardiologist. Note that this advisory does not apply to Riata ST Optim leads.

Technical information

There are several factors that can contribute to lead wear and abrasion in implanted pacing and defibrillation systems, including physiological stresses placed on the lead due to patient anatomy, implant orientation, and mechanical stresses applied from concomitant devices in the body. The main causes of insulation problems are listed below:

• Lead to ICD abrasion
• Lead to lead abrasion
• Lead abrasion caused by something in the heart or vasculature that rubs against the outside of the lead resulting in exposure of the conductors
• Pressure from the clavicle (collar bone)
• "Inside-out" abrasion caused by the movement of the leads within the insulation.
• "Externalised" leads, where the lead is visible outside the lead insulation body on xray or fluoroscopy.

Reported rates of these problems

The manufacturer, St Jude Medical, indicates that a total of 3962 Riata and Riata ST leads were supplied in Australia over the last 9 years. Over 227,000 Riata and Riata ST leads have been supplied world-wide during that time.

Rates of lead failure are likely to be under estimated because not all cases are reported to either the manufacturer or to TGA. However, St Jude Medical has provided estimates of their confirmed incident rates for Australia and world-wide. St Jude Medical reports that the Australian reported incident rate up to 29 January 2012 is estimated to be 1.2% for all cause abrasion with approximately 18% of those exhibiting externalised leads. St Jude Medical has estimated that world-wide (including Australia) reported incident rate up to 30 November 2011 is 0.63% for all cause abrasion, with approximately 15% of those exhibiting externalised leads.

There is some debate in the medical literature^1,2, regarding the rate of these problems, however the Riata and Riata ST Silicone leads have been removed from the ARTG and have not been available in Australia since December 2010. Patients are advised to speak to their cardiologist regarding any concerns they may have.

Reference

1. Hauser, R (et al); Deaths caused by the failure of Riata and Riata ST implantable cardioverter-defibrillator leads; (accepted manuscript 4 March 2012; Heart Rhythm)
2. Carlson, M: ICD leads and postmarketing surveillance (letter to the editor): NEJM; 8 March 2012

Reporting problems to the TGA

Consumers and health professionals are encouraged to report problems with medical devices. 

Refer to the TGA Internet site for more information on the TGA Incident Reporting and Investigation Scheme (IRIS).

The TGA cannot give personal advice about an individual's medical condition. You are strongly encouraged to talk with a health professional if you are concerned about a possible adverse event associated with a medical device.