Both bradycardia or tachycardia can produce significant symptoms.
What Is the AV Node?
It is on the right side of the atrial septum at the junction of the atria and the ventricles.
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What Does the AV Node Do?
The AV node controls the passage of the hearts electrical signal from the atria to the ventricles.
A delay in conduction through the AV node is seen on theECGas an increased PR interval.
(The PR interval measures the time between atrial contraction and ventricular contraction.)
A prolonged PR interval, produced by a delay in AV nodal conduction is called first-degree AV block.
This does not usually cause any symptoms or require specific treatment.
With second degree AV block, some impulses from the atria are blocked from reaching the ventricles.
With third-degree AV block, all of the impulses are blocked.
Occasionally AV nodal block is significant enough to produce severebradycardiaand insertion of apacemakermay be required.
So AV nodal block due to a heart attack is most commonly seen with right coronary artery heart attacks.
A Word From Verywell
The AV node is a very important part of the hearts electrical system.
Disorders of the AV node can produce either tachycardia or bradycardia.
Saremi F, Hassani C, Sanchez-quintana D.Septal atrioventricular junction region: Comprehensive imaging in adults.Radiographics.
2016;36(7):1966-1986.
2019;74(7):e51-e156.
