Electrocardiograms

Electrocardiography is the process of using an electrocardiograph to produce an electrocardiogram 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). Changes in the normal ECG pattern occur in numerous cardiac abnormalities, including:Cardiac rhythm disturbances, such as atrial fibrillation and ventricular tachycardia Inadequate coronary artery blood flow, such as myocardial ischemia and myocardial infarction electrolyte disturbances, such as hypokalemia

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