If palpitations or blackouts are infrequent, it is common not to be able to catch an episode on an ambulatory ECG (see the section on investigations) in this situation, it is possible to use an implantable loop recorder to capture an episode. Indeed NICE recommends the implantation of an ECG loop recorder for infrequent blackouts.
An implantable loop recorder is a small device that are implanted under the skin in a 5 minute procedure with sedation and local anaesthetic.
An implantable loop recorder will monitor the heart rhythm for up to 3 years and so is very likely to record the heart rhythm during an event. A Medtronic LINQ recorder downloads the days recordings each night to a centralised computer over the internet. A report is then sent to the cardiology technicians so that they can alert the consultant if necessary.