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Sick Sinus Syndrome

Sick Sinus Syndrome

What is sick sinus syndrome?

Sick sinus syndrome is a type of abnormal heartbeat, or arrhythmia. If you have sick sinus, you may have episodes when your heart beats very slowly, stops beating for a short while, or beats very rapidly. Sick sinus syndrome is not just one disease, but a collection of arrhythmias.

Normally, a structure in your heart called the sinoatrial (SA) node regulates your heartbeat. Your SA node should keep your heart beating at the right pace. If you have sick sinus syndrome, your SA node no longer controls your heart's rate and rhythm.


What causes sick sinus syndrome?

Possible causes of sick sinus syndrome are many. The most common cause is a gradual loss of SA node function that comes with age. Other possible causes include drug side effects, growths inside your heart, infections that affect your heart, and heart surgery that damages your SA node.

What are the risk factors for sick sinus syndrome?

Sick sinus syndrome affects men and women equally. It can occur at any age, but most often begins at about age 68. Health care providers see it in about 1 out of every 600 people who have heart disease and are older than age 65. You may have an increased risk for sick sinus syndrome if:

  • You have another type of heart disease
  • You take drugs for heart conditions or high blood pressure
  • You have a history of heart surgery
  • You were born with heart disease and needed open heart surgery
  • Sick sinus syndrome has been passed down through your family

What are the symptoms of sick sinus syndrome?

You may have sick sinus syndrome with few or no symptoms. If you do have symptoms, they may include:

  • Dizziness
  • Fainting
  • Shortness of breath, especially with exertion
  • Heart palpitations
  • Chest pain

How is sick sinus syndrome diagnosed?

Your health care provider may suspect sick sinus syndrome based on your symptoms, but they are common in many other diseases. To diagnose your condition, your health care provider will perform an electrocardiogram (ECG), a machine that records your heart's rate and rhythm. If you do not have symptoms at the time of your ECG, it may look normal.

Other possible tests include:

  • An ECG while you walk on a treadmill
  • A Holter monitor, a recorder you wear for over 24 hours that takes an ECG


  • An event recorder, a recorder you wear over several days that samples your heart rate
  • Electrophysiologic testing, a hospital procedure that involves threading catheters into your heart through a vein in your thigh
  • Echocardiogram or ultrasound of your heart, which checks for structural heart problems

How is sick sinus syndrome treated?

You may have sick sinus syndrome without symptoms and not need treatment. However, if you do have symptoms and need treatment, there are options, such as:

  • Medication change. Your health care provider may change your medications if you are taking any drugs known to cause sick sinus syndrome.
  • Blood thinners. Because there is an increased risk for blood clots forming in your heart and causing a stroke, you may need to take a blood thinner as a preventive step.
  • Pacemaker. The most common treatment for people with symptoms is a pacemaker implant. This is a small, battery-powered device that takes the place of your SA node and regulates your heartbeat. A doctor places a pacemaker under the skin of your chest during an outpatient surgical procedure.


What are the complications of sick sinus syndrome?

Sick sinus syndrome tends to start slowly, but gradually worsens over time. When your heart beats too slowly or too quickly, it can lead to complications:

  • You may be injured if you pass out during an arrhythmia.
  • A clot may form in the upper chambers of your heart, break loose, and travel to your brain, causing a stroke.
  • Your heart may get too weak to move blood efficiently through your body, resulting in heart failure.
  • If you need to have a pacemaker, you may have complications from the procedure, such as infection, bleeding, or a collapsed lung. 

Living with sick sinus syndrome

The aging of your SA node causes most cases of sick sinus syndrome, and there’s no way to prevent that. But you can help prevent complications by learning as much as you can about the disease and working closely with your cardiologist to find the best treatment.

You can also make healthy lifestyle changes:

  • Don't smoke.
  • Work with your health care provider to keep conditions like high cholesterol and high blood pressure under control.
  • Eat a heart-healthy diet.
  • Maintain a healthy weight.
  • Get regular exercise.
  • Tell your health care provider if you experience any symptoms.

Key points

  • Sick sinus syndrome is a type of abnormal heartbeat, or arrhythmia.
  • The most common cause is a gradual loss of SA node function that comes with age.
  • You may have no symptoms or you may experience dizziness, fainting, shortness of breath, heart palpitations or chest pain.
  • Sick sinus syndrome may be treated by changing your medications, prescribing a blood thinner, and/or inserting a pacemaker.
  • Not smoking, keeping your cholesterol and blood pressure under control, eating a healthy diet, maintaining a healthy weight, and getting regular exercise can help you control your sick sinus syndrome.


Next steps

Tips to help you get the most from a visit to your health care provider:

  • Before your visit, write down questions you want answered.
  • Bring someone with you to help you ask questions and remember what your provider tells you.
  • At the visit, write down the names of new medicines, treatments, or tests, and any new instructions your provider gives you.
  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your provider if you have questions.
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