It has been confirmed that 745,000 pacemakers have cyber security issues, allowing them to be hacked.

In an advisory note about fixing the issue, The Food and Drug Administration revealed that 465,000 pacemakers in the US were affected.

Abbott, the pacemaker’s manufacturer, told the BBC there was a further 280,000 devices and the flaws could be the cause to devices pacing too quickly or running down their batteries.

According to the BBC, Abbott said some patients might opt to continue with the old firmware as a consequence. “In some cases, doctors and patients will decide that the risks that could be associated with performing the new pacemaker firmware update for some patients may outweigh the benefits,” it said in a note to pacemaker users.

“If you do not receive the update, your pacemaker will continue to function as intended, and you can receive the update at any future time,” it added.

The affected pacemakers are branded as having been made by St Jude Medical, which was acquired by Abbott earlier this year.

Written by Leah Alger