​​How does E.C.G. Machine work ?

E.C.G stands for Electrocardiogram. An Electrocardiogram is a simple, painless test that measures your heart’s electrical activity. It’s also known as an ECG or EKG. Every heartbeat is triggered by an electrical signal that starts at the top of your heart and travels to the bottom. Heart problems often affect the electrical activity of your heart.
Small metal disks called Electrodes are placed on your skin. The electrodes are used to pick up the electrical impulses of the heart. The impulses are recorded, giving doctors a record of your heart’s electrical activity. The electrodes have wires called leads, which hook up to the electrocardiogram machine (E.C.G.).