Implantable loop recorder insertion: what happens and what to expect

Rhythm problems often do not happen on cue. The Worcestershire leaflet explains that when symptoms such as blackouts or palpitations are infrequent, it is not possible to wear a conventional monitor for long enough, so a device is implanted to make the recordings. The Cambridge leaflet says external monitors can be worn for a relatively short time and are less effective at detecting infrequent abnormalities.

It is not the first test for everyone. The Northern Care Alliance leaflet says it is used when short-term monitoring or other tests have not explained the cause, or no diagnosis has been reached. If your symptoms are frequent, a shorter-term monitor may be enough, and your cardiologist will explain which fits your situation.

Other monitors exist, but the Cambridge leaflet says external heart monitors can only be worn for a relatively short period, so they are less effective at picking up infrequent rhythm abnormalities. A loop recorder's advantage is time: the same leaflet says it is designed to stay in for up to three years if necessary.

Instructions differ between units, which is a useful reminder to follow your own letter. The Cambridge leaflet asks you to have nothing by mouth for two hours before your appointment time, while the Worcestershire leaflet says you can eat and drink normally. The Worcestershire leaflet also asks to continue usual medicines including blood thinners, and to have an INR the day before if you take warfarin.

Men may be asked to shave the chest if there is hair, to reduce infection risk and help the dressing stick. You will be asked to wear a gown, and the Cambridge leaflet says your vital signs and a checklist will be completed.

• Download any app your unit asks for in advance, if your phone is compatible.

• Bring a list of your medicines.

The procedure usually takes place in a small theatre or cath lab. Local anaesthetic numbs the skin, and the Cambridge leaflet notes you may feel pushing or pressure but it should not be painful. A small cut, 5 mm wide in that leaflet, is made to the left of the breastbone, the device is injected under the skin, and the wound is closed with surgical glue. The Worcestershire leaflet says the skin is closed either with glue or sticky strips, and rarely a stitch that your GP would remove after 7 days.

The Northern Care Alliance leaflet says you are not sedated. Before you go home you are shown how to record a symptom, with an app, a handheld activator or a home monitor, and you are given an ID card for the device.

The leaflets agree it is a very safe procedure. They list a small risk of bleeding, bruising or infection at the site, and the Northern Care Alliance leaflet adds a possible reaction to the local anaesthetic. The Worcestershire leaflet says bleeding usually stops by itself or with pressure, bruising can be more extensive but fades over weeks, and an infected device may need to be removed along with antibiotic treatment.

None of the leaflets gave a percentage that is reliable enough to quote here. Ask your team what their figure is.

Wound care is simple: the Worcestershire leaflet advises keeping the area dry for five days and not letting a shower hit the site until the dressing is removed. Follow-up is mostly remote. The Northern Care Alliance leaflet describes a telephone check four to six weeks after, then home-monitor transmissions about every three months and clinic visits every 6 to 12 months. Results go to your doctor, and you may not be seen by a cardiologist unless one referred you.

Contact the unit if the wound becomes red, swollen, hot, painful, leaks fluid or bleeds, or if you develop a fever. The Worcestershire leaflet says that if infection is suspected at any time you should return to hospital urgently. If you faint, have chest pain or severe breathlessness, call 999; the recorder is a diagnostic tool and will not provide any therapy during symptoms, as the Northern Care Alliance leaflet says.

Ask what you are being tested for, how long the device will stay in, how recordings are reviewed, what happens if nothing is found, how it is removed and what the wound will look like. Ask about driving, because the underlying symptom may carry a restriction.

Loop recorders are offered in NHS cardiology and in private cardiology, usually after other tests. Whichever route you use, ask who monitors the transmissions and how quickly you would hear about any finding.