St Jude implantable devices when used with the Merlin@home transmitter

Related information

Hazard alert - potential for unintended implanted device software reset

24 December 2014

Consumers and health professionals are advised that St Jude Medical, in consultation with the TGA, has issued a hazard alert for some of its implanted devices that have radio frequency (RF) capability.

It has been identified that, in rare cases, some of these devices may enter back-up mode as a result of an unintended software reset if the patient is being actively monitored by a Merlin@home RF remote monitoring transmitter (model EX1150).

Potentially affected devices include all models of St Jude Medical's Ellipse, Fortify Assura, Unify Assura and Quadra Assura implantable cardioverter defibrillators/ cardiac resynchronisation therapy defibrillators (ICDs/CRT-Ds) and Assurity and Allure pacemakers.

ICDs/CRT-Ds and pacemakers are implantable medical devices that deliver electrical impulses to treat abnormal heart rhythms.

If the above issue occurs, an alert will be sent to the clinic where the patient is normally treated. Additionally, the ICDs/CRT-Ds will deliver a vibratory alert and the pacemakers will sound an audible alert.

In some cases, only involving ICDs/CRT-Ds, the patient may experience inappropriate defibrillation therapy. This would be minor, with the primary symptom being pain.

In the vast majority of cases, normal operation can be restored non-invasively. However, in some cases device replacement may be necessary.

To address this issue, St Jude will update the software of the Merlin@home remote monitoring transmitter. The update will commence in late January 2015 and will be performed automatically over the telephone, broadband or mobile connection normally used by the device. No action is required by the patient.

Information for consumers

St Jude Medical has written to health professionals who manage patients with the potential affected device providing further information about this issue.

If you, or someone you care for, have one of the potentially affected devices and use a Merlin@home remote monitoring transmitter, be alert for vibratory alerts (for ICDs/CRT-Ds) or audible alerts (pacemakers).

Please note that this issue is rare and can usually be corrected non-invasively.

If it does occur, there will be no loss of pacing and defibrillation therapy.

If you have any questions or concerns regarding this issue, talk to your managing cardiologist.

Information for all health professionals

St Jude Medical has written to health professionals who manage patients with the potential affected device providing further information about this issue.

If you are treating a patient who has a potentially affected device and uses a Merlin@home remote monitoring transmitter, advise them of this issue but reassure them that it rare and can usually be corrected non-invasively. Also reassure those patients that, if it did occur, there would be no loss of defibrillation therapy.

If your patients continue to have questions or concerns regarding this issue, refer them to their managing cardiologist.

Information for cardiologists

If you are treating a patient who has a potentially affected device and uses a Merlin@home remote monitoring transmitter, advise them of this issue but reassure them that it rare and can usually be corrected non-invasively. Also reassure those patients that, if it did occur, there would be no loss of defibrillation therapy.

Advise patients to be alert for vibratory alerts (for ICDs/CRT-Ds) or audible alerts (pacemakers). If one is received, they should follow the normal procedures or contact you if they have any concerns.

No changes to patient management, including the patient's remote or in-clinic follow-up schedule, are required.

In the event that a St Jude ICD/CRT-D enters back-up mode, the nominal operational settings will be VVI pacing mode, 67 ppm, 5.0 V/0.6 ms with bipolar pacing output and defibrillation settings of a VF detection rate of 146 bpm and 36 J high voltage therapy.

In the event that a St Jude pacemaker enters back-up mode, it will have output settings of VVI pacing mode, 67 ppm, 5.0 V/0.6 ms with unipolar pacing.

If you have any questions or concerns about this issue, contact St Jude Medical on 02 9936 1215.

Reporting problems

onsumers and health professionals are encouraged to report problems with medical devices. Your report will contribute to the TGA's monitoring of these products. For more information see the TGA Incident Reporting and Investigation Scheme (IRIS).

The TGA cannot give 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.