ECG (Electrocardiogram) - Picture, Image and Reading Interpretation of Electrocardiogram

The ECG is a test that measures the electrical activity in different areas of the heart. Small electrodes are attached to the skin to transmit the electrical activity of the heart to an ECG machine. Signals from the electrodes produce a trace, which is recorded on a strip of paper.The trace can be used to detect any abnormalities in the rate or rhythm of the heartbeat.

In addition, the ECG can demonstrate areas of damage to the heart muscle, such that might occur during a heart attack. Disease caused by narrowing of the blood vessels that supply the heart muscle (coronary heart disease) can also be identified. Most ECGs are performed with the patient lying down and inactive; a resting ECG.

Even in severe heart disease, the resting ECG can be normal, and if this is the case, the patient is asked to undergo an exercise ECG, or exercise stress test. This usually entails walking on a treadmill untill symptoms such as chest pain occur, or the pattern on the ECG changes to indicate that the blood supply to the heart muscle is inadequate during exertion.

If the patient is being investigated for palpitations, it is rare for the condition, unless very frequent, to be picked up on a resting ECG. Therefore, the patient is connected to a small machine that will monitor the ECG over a full day. This is known as a 24-hour tape, and the patient can record when symptoms are felt. Results can be compared to the corresponding part of ECG recording.