ECG (Heart Tracing)
ECG (called EKG in USA) stands for ElectroCardioGram. This test looks at the electrical activity in the heart.
How Is It Done?
The first step is to attach adhesive electrodes to the chest and limbs. It may be necessary to shave the chest to get good skin contact. In women, the elctrodes are places under/around the left breast. The machine will then be attached to the electrodes. At this point the patient will be asked to lie very still while the machine takes a recording for about 10 seconds. The test is not painful or uncomfortable.
Why Is It Done
The usual reasons for an ECG are chest pain, palpitations, fast/slow/irregular pulse, shortness of breath or unconsciousness. Many doctors also request an ECG as a baseline investigation. It does not necessarily mean something is wrong with your heart.
What Does It Show
The heart is a muscular organ with its own "wiring". For each heartbeat, an electrical impulse travels through the wiring in a specific way, causing the muscle to then contract in a coordinated and efficient way. The ECG shows how the current is moving through the wiring and muscles. Many conditions can cause the current to travel in an abnormal way.
There may be abnormalities in the rate, rhythm or shape of the deflections in the ECG. Some are specific to certain conditions. Others are more general. The ECG is always interpreted in light of the patients history and examination. Comparison with previous ECGs is also helpful. The ECG is not an end in itself.