Sinoatrial

Node The sinoatrial node (SAN) is an important pacemaker of the heart. It is an area of specialized tissue located in the upper wall of the right atrium. The SAN initiates electrical impulses that cause the atria of the heart to contract and pump blood to the ventricles. The SAN is the heart's primary pacemaker and sets the normal rate of 60-100 beats per minute. In addition to controlling heart rate, the SAN also controls the duration and pattern of the electrical activity of the heart muscle. Abnormalities in the SAN can lead to arrhythmias, which can be disruptive or even life-threatening. Treatments of arrhythmias may include lifestyle modifications, medications, or procedures such as catheter ablation or cardiac pacemaker implantation.