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Basic principles of electrocardiographic interpretation

Ary L Goldberger, MD
Section Editor
David M Mirvis, MD
Deputy Editor
Gordon M Saperia, MD, FACC


The electrocardiogram (ECG) is a graphical record of electric potentials generated by the heart muscle during each cardiac cycle. These potentials are detected on the surface of the body using electrodes attached to the extremities and chest wall, and are then amplified by the electrocardiograph machine and displayed on special graph paper.

This topic will review the basic aspects of ECG interpretation, including:

The cardiac electrical cycle

ECG waveforms and intervals

ECG leads


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Literature review current through: Aug 2017. | This topic last updated: Sep 08, 2015.
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