Definition
The SA node, short for sinoatrial node, is the heart's natural pacemaker. It's a cluster of cells in the right atrium that generates electrical signals. These signals trigger each heartbeat, setting the rhythm for the heart. The SA node controls how fast your heart beats, speeding up when you exercise and slowing down when you rest. It's like the metronome for your heart, keeping everything in time. Proper function of the SA node ensures a regular and coordinated heartbeat, essential for circulating blood throughout the body.