Which interval on the electrocardiogram mainly reflects the conduction delay in the atrioventricular node?
Answer and explanation
Correct answer: C. The PR interval
- Step 1: The PR interval runs from the start of atrial depolarization to the start of ventricular depolarization. Step 2. Most of it is the slow conduction through the AV node. Answer: the PR interval. Why not the others: the QRS is ventricular depolarization, the QT interval is ventricular depolarization plus repolarization, and the ST segment is the plateau.
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