4,200
edits
Line 9: | Line 9: | ||
{{clr}} | {{clr}} | ||
==The PQ interval== | ==The PQ interval== | ||
[[Image:PR_interval_buildup.svg|300px|thumb|right|The PR duration depends on the conduction velocity in the atria, AV node, His bundle, bundle branches and Purkinje fibers.]] | |||
'''The PQ interval starts at the beginning of the atrial contraction and ends at the beginning of the ventricular contraction.''' | '''The PQ interval starts at the beginning of the atrial contraction and ends at the beginning of the ventricular contraction.''' | ||
The PQ interval (sometimes referred to as the PR interval as a Q wave is not always present) indicates how fast the action potential is transmitted through the AV node (atrioventricular) from the atria to the ventricles. Measurement should start at the beginning of the P wave to the beginning of the QRS segment. | The PQ interval (sometimes referred to as the PR interval as a Q wave is not always present) indicates how fast the action potential is transmitted through the AV node (atrioventricular) from the atria to the ventricles. Measurement should start at the beginning of the P wave to the beginning of the QRS segment. |