Normal pacemaker of the heart

The normal pacemaker of the heart is a specialized tissue located at the entrance of the superior vena cava in the right atrium, known as the sinoatrial (SA) node. The SA node has automaticity, meaning it can spontaneously generate electrical impulses. These impulses travel through the heart in a regular rhythm and frequency, triggering the contraction and relaxation of cardiac muscle cells, thereby maintaining normal heartbeats. As the heart's primary "command center," the SA node ensures the rhythm and stability of cardiac activity.

When the SA node functions properly, it automatically adjusts the heart rate according to the body's physiological needs, ensuring adequate blood supply under different activity levels. If you experience any cardiac discomfort, you should seek medical attention promptly.