The Electrocardiogram (ECG)
If you are suspected of having a heart disease, you will probably have a heart trace, known as an electrocardiogram (ECG, also known as EKG). This test will record any abnormality in the electrical pathways of the heart. ECGs are also done as part of routine health screenings.
The heart is a muscular pump made up of four chambers: two upper chambers (the atria), and two lower chambers (the ventricles). Every heart beat is coordinated by a naturally occurring electrical system that sends electrical impulses through the heart. The ECG translates this electrical activity into line tracings on paper.
When Is It Done?
An electrocardiogram is done to:
• Investigate the cause of chest pain eg. angina, heart attack, pericarditis etc.
• Investigate the cause of other symptoms of heart disease eg. shortness of breath, dizziness, palpitations etc.
• Find out if the walls of the heart chambers are too thick (hypertrophied), seen sometimes in poorly controlled hypertension.
• Check on the health of the heart when other diseases are present eg. hypertension, diabetes, hypercholesterolaemia.
• Check how well medicines are working and whether they are causing side effects that affect the heart.
• Check how well mechanical devices (such as pacemakers) are working to control the heart rate.
How Is It Done?
The ECG is a completely safe test with no risks involved.
You will be asked to lie on a bed with your chest exposed. Several electrodes are attached to the skin at several points on the body. These electrodes are covered in a sticky gel to ensure a good contact, and are usually placed on your ankles, wrists and across the chest. Nowadays, disposable electrodes are used which do not require the use of gel.
The electrodes are hooked to a machine that traces your heart's electrical activity onto paper. The tracing records the heart rate and rhythm, and whether the muscle is conducting electricity normally.
You will be asked to lie very still and breathe normally during the test. Sometimes you may also be asked to hold your breath. You should not talk during the test.
The entire procedure should not take more than 15 minutes.
Further Reading
The article above is meant to provide general information and does not replace a doctor's consultation.
Please see your doctor for professional advice.