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What You Should Know About Sick Sinus Syndrome

What is sick sinus syndrome?

Sick sinus syndrome is the name for several conditions in which the sinus node does not work the right way. The sinus node is a natural pacemaker in your heart that helps your heart beat steadily. An electric current starts in one of the upper chambers (called the atria) of the heart and goes through the heart to the bottom chambers (called the ventricles). The sinus node can increase your heart rate during times of high demand, such as during exercise. If you have sick sinus syndrome, your heart rate may be too slow or too fast to meet the needs of your body.

About one in 600 people with heart problems have sick sinus syndrome. It usually affects people who are at least 60 years old. Women are affected about as often as men.

How does my doctor know that I have sick sinus syndrome?

Some people with sick sinus syndrome do not even feel ill or only have mild feelings of illness. Other people have symptoms that come and go. Here are some possible symptoms of sick sinus syndrome:

• Feeling like you are going to pass out
• Feeling like your heart is skipping beats or beating too fast or too slow
• Dizziness
• Chest pain
• Shortness of breath
• Difficulty thinking or remembering things
• Feeling tired

Your doctor may be able to find sick sinus syndrome by doing some tests. One of these tests is electrocardiography, also called ECG. During this test, your doctor will have you lie down so your heart can be monitored. The ECG machine makes a picture, or tracing, that shows your heart's electrical signals. In addition, your doctor may have you wear a special monitor, called a Holter monitor, for a few days to keep track of your heart's electrical signals.

Other medical problems can cause the same symptoms as sick sinus syndrome, so it's important to find out what is causing your symptoms.

How is sick sinus syndrome treated?

Most people with sick sinus syndrome will need to have an artificial pacemaker inserted in their body. A pacemaker is a small electronic device that is put under the skin on your chest. It helps your heart keep a regular beat, especially when your heart beats too slowly.

Your doctor may prescribe medicines if you have a pacemaker and your heart rate is too fast. In addition, your doctor may want to change some of your other medicines, because some medicines can make sick sinus syndrome worse.

Some people with sick sinus syndrome who also have other medical problems may be at greater risk of having a stroke. Doctors might give these people a blood-thinning medicine, such as warfarin (brand name: Coumadin).