Feb 4, 2021 · The normal PR interval is between 120 – 200 ms (0.12-0.20s) in duration (three to five small squares). If the PR interval is > 200 ms, first degree heart block is said to be present.

In this article, I am going to show you a simple way on how to measure the PR interval. At the end of the article, you can test your knowledge on how to measure PR intervals.

Oct 30, 2025 · The PR interval is measured using an electrocardiogram, also called ECG or EKG. This is a painless test performed on cardiac patients in order to measure the electrical …

Mar 17, 2025 · The PR interval is measured from the beginning of the P wave to the beginning of the QRS complex. It comprises the P wave and the PR segment. The interval should be …

This video explains how to measure the PR interval on an EKG strip. In order to do this you must know how the normal measurement of a PR interval and how to count the small blocks...

Aug 16, 2025 · Learn how to interpret the PR interval on ECG — including normal physiology, how to measure it, causes of short and prolonged PR intervals, PR depression in pericarditis …

Aug 4, 2025 · To measure the PR interval, locate the beginning of the P wave, the first positive deflection on the ECG strip. From this point, measure horizontally to the start of the QRS …

Nov 8, 2021 · Measurement of the PR interval reflects the amount of time from the beginning of atrial depolarization to the beginning of ventricular depolarization. Plainly stated, this …

Remember that the PR interval starts at the start of the P wave and ends at the start of the QRS: There are 2 questions you must ask when you measure the PR interval:

Jul 9, 2020 · There are three ways to calculate a heart rate using an EKG. If the rhythm is regular, the small box method and big block method can be used. If the rhythm is irregular, the six …