Atrioventricular Block ECG tracing

Atrioventricular block
From Wikipedia, the free encyclopedia

An atrioventricular block (or AV block) is a type of heart block involving impairment of the conduction between the atria and ventricles of the heart. It usually involves the atrioventricular node, but it can involve other structures.
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There are three types:
First degree AV block
Second degree AV block
Third degree AV block

Source of Image

http://www.emedicine.com/med/TOPIC189.HTM