Sinoatrial node

The sinoatrial (SA) node, also known as the pacemaker of the heart, is a small group of specialized cells located in the wall of the right atrium of the heart. The SA node has the ability to spontaneously generate electrical impulses, which spread through the heart and stimulate the contraction of the heart muscle. This process helps to regulate the heart rate and ensure that the heart pumps blood effectively to the rest of the body. The SA node is responsible for initiating each heartbeat, and it typically has a faster firing rate than other parts of the heart. Dysfunction of the SA node can lead to various heart rhythm disorders, such as sinus bradycardia (slow heart rate) or supraventricular tachycardia (rapid heart rate).