Electrocardiography

Examination of the heart's electrical activity

Electrocardiography is the process of using an electrocardiograph (a device) to produce an electrocardiogram (a recording, often called an ECG or EKG) that shows a line graph of the heart's electrical activity through repeated cardiac cycles. It is an electrogram of the heart which is a graph of voltage versus time of the electrical activity of the heart using electrodes placed on the skin. These electrodes detect the small electrical changes that are a consequence of cardiac muscle depolarization followed by repolarization during each cardiac cycle (heartbeat).

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