Changing PR interval

changing PR interval is different for each beat. Most often it progressively gets longer and longer, then there is a dropped beat before it starts again. This is usually caused by a second degree conduction block (or delay) at the AV node, called Wenckebach. If the PR interval is constantly changing without evidence of progressively lengthening, there may be a complete AV block.

See also: PR interval & segment

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In the ECGquest archives, this ECG has been tagged with: - Chest pain 12-Lead Changing PR interval Grouped Inferior ST elevation Normal Axis Reciprocal ST depression Second degree AV block type 1 - Wenckebach Acute Inferior MI ECG Interpretation CC-BY-NC-SA
ECG Blog #154 (STEMI – Inferior – Posterior – LVH – Mobitz – AV Block)