The “pacemaker” of the heart starts an electrical impulse in the right atrium to cause the atria to contract. What is the “pacemaker” of the heart?

The sinoatrial (SA) node, located in the right atrium, normally starts the heart’s electrical impulse and sets the pace for each heartbeat. The impulse then travels to the AV node and onward through the bundle of His and Purkinje fibers. Therefore, the pacemaker is the SA node.

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