ARRHYTHMIA DETECTION TESTS
Diagnostics
Electrocardiogram (ECG)
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Over 100 years old test and still an indispensable tool for the cardiologist
What is an Electrocardiogram (ECG) test and how does it work?
An electrocardiogram, more commonly known as an ECG, is a quick and simple test which looks at the electrical activity of the heart.
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Why would you need an electrocardiogram (ECG) test?
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An ECG is used as a baseline test to look for evidence of cardiac damage, cardiac enlargement and/or a rhythm disturbance.
During the procedure
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For an ECG, you will be asked to remove the clothing from the upper half of your body to allow the cardiac physiologist access to your chest. Access to the ankles is also required to produce an accurate ECG trace, and therefore it will be necessary to remove boots and socks/tights. You will be offered a gown to wear.
The test is performed with you lying on a couch with your upper body positioned slightly upwards. Four small sticky sensors called electrodes are placed on your ankles and wrists and six more are placed in very specific places on your chest. Leads are attached to the ten electrodes which produces twelve ECG signals representing different surfaces of the heart.
You will be asked to keep still and breathe normally and, once the signal has produced a clear trace, the physiologist will record a 10-second snapshot of your heart’s activity. On some occasions, a longer recording called a rhythm strip may be taken which is useful in patients with irregular heart rhythms or if a longer recording is required for measurements.
After the recording has finished, the leads are disconnected, the electrodes are removed, and any gel residue is wiped clean.
There is no special preparation for an ECG, however the use of body moisturizers does prevent the electrodes from sticking and therefore please avoid using moisturizers on the day of your appointment.
Aftercare
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None needed
Diagnostics
24H-Holter ECG (Electrocardiogram; up to 7 days)
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ECG recording for at least 24hours to detect changes of the heart rhythm and rate which only occur at times and do not persist.
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What is a Holter ECG and how does it work?
The Holter ECG is a small electric device capable of recording your ECG continuously via thin cables connected to ECG leads attached to the skin of your chest.
It can be programmed for 24hours -7 days recordings, the longer the recording period, the more likely it is to detect an arrhythmia.
The small device is being placed in a little pouch and can be carried around in your pocket.
Why would you need a Holter ECG ?
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Some arrhythmias, changes of rhythm and heart rate, may occur only at times and unfortunately they may not be present at exactly the time your doctor checks your ECG. Especially when patients are symptomatic with fainting and dizziness, arrhythmias which are coming and going are a highly suspected cause.
Further it may be used to evaluate the effect of cardiac medications and your heart rate during the day or at night.
The Holter ECG is a simple, non-invasive test to record your heartbeat continuously and to evaluate for possible problems, even when you are at home or at work.
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During the Holter ECG
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It is best to continue business as usual. No changes of your daily activities are required, to the contrary, it is expected of you to continue the same level of exercise and stress as usual.
However, since the electrical equipment is not be waterproof, you cannot shower, go swimming or to the sauna.
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Aftercare
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None necessary
Diagnostics
Electrophysiology (EP) Study
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Minimally invasive maneuvers to stimulate the heart’s electrical system performed to analyze the electrical activity of your heart and suspected errors causing arrhythmias.
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What is an Electrophysiology Study and how does it work?
An electrophysiology (EP) study is undertaken to analyze your heart's electrical activity and is used to diagnose abnormal heart beats and what may be causing them.
It is performed by inserting wire catheters and electrodes to the heart via a vein in the groin.
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Why do I need an Electrophysiology (EP) Study?
These studies may be used to make a primary diagnosis, to evaluate the efficacy of antiarrhythmic drugs, or to map arrhythmia foci before catheter ablation.
They are often performed when the normal ECG does not provide enough information to determine the exact cause of the arrhythmia or the exact location where it arises inside the heart.
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During the Electrophysiology Study
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The EP-study is being performed in a hemodynamic interventional suite equipped with additional devices capable to perform these specific investigations.
You will be lying down on the interventional table and draped sterile. You may receive sedation, depending on the intervention performed. In most cases only local anesthesia under the skin will be necessary prior to the needle puncture in your groin vein through which recording and stimulating electrodes are inserted into the heart chambers.
The test measures the heart's electrical signals to assess the electrical function. The heart will be stimulated with the electrodes and also with medication that is designed to speed up the heart rate to provoke certain abnormal rhythms in the controlled environment of the cardiac EP lab. While this inducement of abnormal rhythms will feel uncomfortable, it is necessary to evaluate any heart conditions present.
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Aftercare
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Once the test has finished, the usual recovery time is 4-6 hours, after which time many patients are allowed to go home. Occasionally an overnight stay will be needed.
Implantable Loop Recorder (ILR) / Subcutaneous, Continuous ECG Monitor
Diagnostics
An implantable loop recorder (ILR) monitors the heart rhythm continuously for up to three years.
What is an implantable loop recorder (ILR) and how does it work?
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An implantable loop recorder (ILR) monitors the heart rhythm continuously for up to three years.
The ILR is a very small device, no larger than a standard pencil tip , which is inserted under the skin of the chest in a procedure carried out under local anesthetic. Patients will return home the same day.
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Why would you need an implantable loop recorder (ILR)?
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It is predominantly used for patients who suffer random fainting spells or infrequent palpitations and as other monitoring devices, such as an electrocardiogram (ECG) or ECG Holter, do not last long enough to capture the necessary data for diagnosis.
They are also used for patients who have had a stroke of unclear cause to determine if this is due to occasionally occurring (=paroxysmal) atrial fibrillation and to help prescribe the correct medication.
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During the procedure
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You will be awake; no anesthesia or sedation are necessary. Local anesthetic will be injected into the skin to numb the area. The small skin insertion is max. 1 cm large. The small device is being inserted through the incision under the skin. 1-2 skin stitches may be necessary to close the skin insertion after the device implantation.
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After a maximum of three years, or once the necessary data has been obtained, the ILR is being removed under local anesthetic.
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Aftercare
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Keep sterile dressing for 4-5 days; removal of stitches after maximum 10 days. Occasionally bruising and discomfort in the area of the ILR may occur but this often settles after a short period.
Pacemaker and Defibrillator (ICD) Interrogation And Programming
Diagnostics
At least once a year checks are mandatory
What is a pacemaker /defibrillator interrogation and how is it done?
Patients who have a pacemaker or implantable defibrillator (ICD) fitted will need to have them checked on a regular basis. Depending on the device and individual circumstances, checks should occur in three, six or twelve monthly intervals.
In some cases, especially after the device has been initially fitted, it may be necessary to undergo checks earlier.
Based on the performance and personal needs of the patients, programming changes may need to be made after the initial implantation.
Interrogation of the device recording of arrhythmia events are also important for further medical care.
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Why would you need a pacemaker /ICD interrogation?
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Every patient with an implant device needs a routine check of device function and arrhythmia events in predetermined intervals to check the correct functioning and look for abnormal events.
Reasons to undergo additional, out of the routine schedule device checks:
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any abnormal heart beats,
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unusual heart rate changes
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dizziness and fainting
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firing of an electroshock
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During the check
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The check will normally last 15-30 minutes, depending on the type of device being checked and whether any adjustments are required. ECG electrodes will be placed on the wrists and ankles and a magnet will be placed over the device, which is linked to a computer. The doctor will monitor the device and then make any necessary adjustments to optimize its function using the programmer.
Normally batteries last 8-10 years and the doctor will be able to advise on the remaining battery life and then schedule when a replacement procedure should take place.
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Aftercare
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None needed