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The Heart's Electrical System

Home > Medical Group Services > Cardiology > About the Heart > The Heart's Electrical System

In order for the heart to do its work of pumping oxygen-rich blood to the body, it needs an electrical impulse to generate a heartbeat.

This electrical impulse originates from the sinus (SA) node, located in the right atrium. The SA node functions as the heart’s natural pacemaker, setting the pace for the heartbeat.

From the SA node, the electrical impulse travels through the atria causing them to contract. The electrical impulse then proceeds to the atrioventricular (AV) node, located between the atria and the ventricles.

The AV node takes the signal from the atria and passes it across the Bundle of His to the ventricles. This causes the ventricles to contract and pump blood. The contraction on the ventricle is what you feel when your heart beats.