$Unique_ID{BRK00454} $Pretitle{} $Title{Sinus of the Heart} $Subject{sinuses heart beat pacemaker Circulatory sinus node nerve impulse impulses rhythm sequence muscle contractions sick syndrome SSS pacemakers infections rheumatic infection} $Volume{G-3} $Log{} Copyright (c) 1991-92,1993 Tribune Media Services, Inc. Sinus of the Heart ------------------------------------------------------------------------------ QUESTION: I am told I am suffering from a sick sinus in my heart. It may mean that I must have a pacemaker put in to keep my heart beating, and I need to know all I can about this. I thought sinuses were in your nose; can you tell me about this sinus in my heart? ------------------------------------------------------------------------------ ANSWER: Though the words are they same, the anatomical structures are quite different. Sinuses in the head are open spaces in the bones of the head. The sinus in the heart is called the "sinus node", and is made up of cells that are responsible for kicking off the nerve impulses that control the beat of your heart. These impulses travel along a conduction system within the heart and assure that the rhythm and sequence of the heart muscle contractions will propel the blood through the heart and thus through the entire body. The "sick sinus syndrome" (SSS) is the condition in which the system of impulse formation and conduction fails to operate properly, slowing the heart beat or reducing its effectiveness. It is most common in patients over the age of 60 and is the reason for the placing of about half of the permanent pacemakers in use in the United States. There are a number of diseases that can cause SSS, including situations where the blood flow to the heart is reduced, infections of the heart and rheumatic heart disease. ---------------- The material contained here is "FOR INFORMATION ONLY" and should not replace the counsel and advice of your personal physician. Promptly consulting your doctor is the best path to a quick and successful resolution of any medical problem.