What is Sick Sinus Syndrome (SSS)?
Sick Sinus Syndrome (SSS) is not a single disease but a group of heart rhythm abnormalities caused by improper functioning of the sinus node—the heart’s natural pacemaker located in the right atrium. In SSS, the sinus node produces irregular electrical signals, leading to heart rates that may be too slow (bradycardia), too fast (tachycardia), or alternating between the two, often in combination with atrial fibrillation or atrial flutter. This disrupts the heart’s normal ability to adjust its rate in response to activity and rest. Treatment commonly involves implantation of a pacemaker, sometimes along with medication to manage associated rhythm disturbances.