Heart Rhythm Monitoring
Approaching 100,000 people in the UK die each year as a result of a treatable but undetected heart rhythm disorder. This highlights the vital importance of effective diagnosis. Even routine manual pulse checks can detect many arrhythmias for diagnostic testing.
Monitoring of the heart’s rhythm is the cornerstone of the diagnosis of cardiac arrhythmias. This is achieved in various ways, and also under different conditions where a clinician will attempt to replicate symptoms, reveal a hidden arrhythmia and correlate arrhythmias with specific events. In heart rhythm testing, the electrical activity of your heart is recorded to identify problems. Common heart monitoring techniques include:
- Electrocardiogram (ECG or EKG)
- Holter monitor (24h monitoring for days at a time)
- Implantable loop recorders (months of continuous monitoring)
In recent years, new technologies have also been developed to support patients who wish to monitor their heart rhythm and share results with their doctor. You can learn more about these devices by visiting our Lifesaving and heart rhythm devices page here.
Over the years, the ECG has been developed to become one of the most important tests in the investigation of heart-related problems. It can help a doctor understand the possible role of the heart in a person’s symptoms or problem.
If you are suffering with unexplained blackouts or a related condition, then your specialist or doctor may ask for this test. Every patient presenting with blackouts should undergo an ECG. A resting ECG is an important test as it may help to rule out many underlying heart conditions.
The test is painless and harmless, recording electrical impulses that come from your heart. At no point does this put electricity into your body, or cause any side effects.
An ECG test takes about five minutes. Electrodes (small sticky pads) are attached to your arms, legs and chest and the wires lead to the ECG machine. The machine can then read what is happening to your heart and record the information onto paper.
Through the different electrodes, the ECG gives 12 different electrical pictures of the heart. For this reason it is often also called a ‘12 lead ECG’. The ECG will tell the specialist whether your heart rate is too fast, too slow or irregular.
It is common to have more than one ECG recorded while being investigated for blackouts. This gives individual clinicians a chance to review a fresh test to give their own opinion on the heart trace. This can also help if the trace changes over time.
If your symptoms ‘come and go’ your doctor might suggest a Holter Monitor test, which is a continuous ECG recoding over approximately 24 hours.
Again, electrodes will be placed on your body, and this time they will be taped down. During a Holter Monitor test the wires will be attached to a smaller, portable device which can be strapped to the chest. After the specified time period the monitor can be returned to your doctor to see whether any arrhythmias have been indicated.
Implantable Loop Recorder (ILR)
What is an implantable loop recorder?
Some arrhythmias such as syncope (blackouts or fainting) are intermittent, making it difficult to detect them with ECG or 24-hour monitoring. In these cases, a clinician might consider an implantable loop recorder (ILR).
An ILR is used to monitor heart rhythms for months at a time if the symptomatic episodes are less frequent than every 30 days. The device can remain in place for up to three years.
An ILR is a thin device that is inserted just beneath the skin in the chest area. Once implanted, an ILR can determine whether fainting is related to a heart rhythm problem.
Fitting an ILR
If you need an ILR, the fitting is carried out in a day clinic and takes between 15 – 20 minutes. A local anaesthetic is used to numb a small area of your skin. Once the device has been positioned under the skin the incision is stitched.
A small dressing will be applied and you will be advised when to remove it. You might be given antibiotics to minimise infection. The wound should be kept clean and dry until it is healed, although it is safe to bathe and shower.
A clinician will program the ILR to the required settings, this only takes a few minutes. Programming and data retrieval is done wirelessly, and this procedure is painless. Before you return home the physiologist will explain how and when to use your activator.
Using an ILR
An ILR can capture your heart’s activities during a blackout. This will allow the doctor to diagnose or rule out an abnormal heart rhythm.
To capture and record an episode, you are required to place a hand held activator over the ILR. When in place, press the button in order for the device to save the information. This should be done whilst experiencing symptoms or as near to the event as possible.
It is important to carry the activator with you so that any episode can be recorded.
You will then be asked to return to the ECG department of the hospital for the results to be downloaded.
You may have received a loop recorder with remote capabilities. This will mean you can send any stored information to your doctor via a phone line from your own home without having to go to hospital.
In some instances, these results may produce a diagnosis. If so, the ILR may be removed and appropriate treatment will be given.
Removing your ILR
Once your heart’s activity has been recorded during your symptoms and the doctor is satisfied that any heart-related causes are identified or ruled out, the device will be removed.
The removal of the ILR is similar to when you had it implanted and can be carried out in a day clinic.