In sinus bradycardia, what is the normal range for the PR interval?

The normal range for the PR interval in a healthy adult is 0.12 to 0.20 seconds. This interval represents the time it takes for electrical impulses to travel from the atria to the ventricles, reflecting normal conduction through the atrioventricular (AV) node. In the context of sinus bradycardia, which is characterized by a slower than normal heart rate while maintaining a usual rhythm generated from the sinoatrial node, the PR interval should still fall within this normal range. Maintaining a PR interval within this range signifies that the conduction through the AV node is functioning properly, even though the heart rate is lower.

Intervals that fall outside this normal range, whether shorter or longer, can indicate various pathological conditions or conduction delays, which would not apply to a case of simple sinus bradycardia. Understanding this is crucial for accurately interpreting ECG readings and assessing cardiac health.