What rhythm is initiated by the SA node?

sinus rhythm
In a healthy heart, the SA node continuously produces action potentials, setting the rhythm of the heart (sinus rhythm), and so is known as the heart’s natural pacemaker.

What is the relationship between the SA node and AV node?

The SA (sinoatrial) node generates an electrical signal that causes the upper heart chambers (atria) to contract. The signal then passes through the AV (atrioventricular) node to the lower heart chambers (ventricles), causing them to contract, or pump. The SA node is considered the pacemaker of the heart.

How do the SA and AV node work together?

The SA node (called the pacemaker of the heart) sends out an electrical impulse. The upper heart chambers (atria) contract. The AV node sends an impulse into the ventricles. The SA node sends another signal to the atria to contract, which starts the cycle over again.

What controls the SA node?

The autonomic nervous system, the same part of the nervous system as controls the blood pressure, controls the firing of the SA node to trigger the start of the cardiac cycle.

What does the AV node regulate?

The AV node controls the passage of the heart’s electrical signal from the atria to the ventricles. After an electrical impulse is generated by the sinus node (located at the top of the right atrium), it spreads across both atria, causing these chambers to beat.

How SA node is different from AV node One major difference?

The main difference between SA node and AV node is that the SA node generates cardiac impulses whereas the AV node relays and intensifies cardiac impulses. SA node and AV node are two elements of the cardiac conduction system that controls the heart rate.

What is intrinsic rate of SA node?

At rest, the SA nodal myocytes depolarize at an intrinsic rate between 60 and 100 beats per minute, which is generally considered a normal heart rate. The autonomic nervous system tightly controls input into the sinus node.

Why the SA node acts as heart’s pacemaker?

The sinoatrial (SA) node or sinus node is the heart’s natural pacemaker. It’s a small mass of specialized cells in the top of the right atrium (upper chamber of the heart). It produces the electrical impulses that cause your heart to beat. It allows the pacemaker to fire when the heartbeat is too slow.

What are the SA and AV nodes made of?

The sinoatrial (SA) and atrioventricular (AV) nodes are specialized centers of the heart conduction system and are composed of muscle cells with distinctive morphological and electrophysiological properties.

Where are the AV and SA nodes located?

The SA node is also called the sinus node. The electrical signal generated by the SA node moves from cell to cell down through the heart until it reaches the atrioventricular node (AV node), a cluster of cells situated in the center of the heart between the atria and ventricles.