ECG stands for electrocardiogram, and it is a test used to check the heart's electrical signals. Stickers are stuck to your chest, arms, and legs, and these detect electrical signals produced by the heart with each beat. The stickers transmit information to a device that produces a graph of the signals.
You can have an ECG in different situations. There is a resting ECG that is performed as you are relaxed and sitting or lying down. An ambulatory ECG is done over a period of one to three days and examines your heart's electrical signals over an extended period. The device for an ambulatory ECG is small and means you can go about your daily life without it being too cumbersome. The final type of ECG is a stress or exercise ECG. This is where the hearts electrical signals are monitored whilst you are performing increasing amounts of exercise on a device such as a treadmill. This examines your heart's electrical signals as it has to work harder under duress.
Because an ECG examines electrical signals, it gives your doctor lots of information about whether your heart's electrical output is synchronised and working as it should. Specifically, it examines your heart rate, heart rhythm, the efficiency of electrical signals through your heart muscle, and whether there is any damage to the heart. It can also point to where any damage in the heart is. ECGs are very helpful, for example, if you have chest pain; it indicates whether you are having or have recently had a heart attack, and the location in the heart that damage has occurred. Those suffering palpitations may be sent for an ECG, which can indicate a problem with the rhythm of your heart and whether it is beating irregularly. Sometimes an ECG will be used simply as a screening test to ensure there are normal electrical signals in your heart.
The graph an ECG produces can be read and interpreted straight away. If you are in hospital with a medical problem it is likely that a doctor will look at your graph soon after it is done. If your doctor has sent you for an ECG routinely it may get reviewed at a later date, as they are not expecting to find anything concerning. You should discuss the results with your doctor, depending on the specific situation you are in.
There is nothing to worry about with an ECG, it shouldn't cause any pain other than the stickers sometimes getting stuck in your skin or hair. No electricity is put through the body, it simply reads the electrical signals your heart is naturally generating.