The TGA is warning cardiologists to stop implants of a cardiac pacemaker because of a battery malfunction that could causes loss of telemetry and pacing.

The affected device is the Nanostim leadless cardiac pacemaker manufactured by St. Jude Medical.

In a hazard alert issued late yesterday, the TGA told cardiologists to stop implanting the device into new patients after the device manufacturer said it had received reports of lost telemetry and pacing output in seven patients more than two years after receiving the implantable device.

The company clarified that there have been no reports of patient injuries associated with the malfunction.

According to the TGA, the pacemakers have been implanted into 22 Australian patients as part of the Nanostim Leadless II IDE/CAP Study – which has now been halted following the discovery of the battery malfunction last month.

In a letter sent to doctors in October, St Jude Medical recommended that cardiologists replace the device in pacemaker dependent patients adding that priority should be given to patients who have had the device implanted the longest.

More intensive follow up and monitoring is recommended for non-pacemaker dependent patients who have had the devices implanted for two or more years.

Meanwhile, patients who have not previously been documented as pacemaker dependent should be reassessed for pacemaker dependence, the company said.

The hazard alert marks the second for St Jude Medical heart devices in as many months.

The company issued a recall of some of its other implanted heart devices in October due to risk of premature battery depletion, which was linked to two deaths in Europe.

The TGA has said that any cardiologists participating in the Nanostim Leadless II IDE/CAP Study should contact affected patients to discuss this issue.