What is the normal length of the PR interval in seconds?

The normal length of the PR interval ranges from 0.12 to 0.20 seconds, which signifies the time it takes for electrical impulses to travel from the atria to the ventricles through the AV node. A PR interval within this range indicates healthy conduction between these cardiac structures, reflecting that the heart's electrical system is functioning properly.

Intervals shorter than 0.12 seconds may suggest conditions such as a bypass tract or pre-excitation syndromes, while intervals longer than 0.20 seconds may indicate AV block or delayed conduction. Knowing the standard range is crucial for accurately interpreting electrocardiograms (ECGs) and recognizing potential cardiac issues.