electrocardiography: Quick Facts

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Last updated

Oct. 9, 2026

Facts

Also Known As	EKG • electrocardiogram • ECG

Photos and Videos

Diagram of the human heart showing the electrical conduction system, with labeled pathways from the sinoatrial node to the atrioventricular node, bundle of His, and bundle branches, along with heart chambers and major vessels.

Side-by-side diagram showing a normal electrocardiogram (ECG) waveform with labeled P, Q, R, S, and T deflections on the left, and a labeled anatomical illustration of the heart's impulse-conducting system on the right, highlighting nodes, bundle branches, and heart chambers.

intensive care unit

automated external defibrillator

What does an electrocardiogram show?

How the pacemaker transmits electrical impulses through the heart

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Topics

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human cardiovascular system: Electrocardiogram

Key People

Einthoven

Willem Einthoven

Dutch physiologist

vintage Leica photo camera at KPI Museum, July 24, 2015, in Kiev, Ukraine

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