Sick sinus syndrome (SSS) is the name that doctors use to refer to heart rhythm problems. These occur when the sinus node, the heart’s natural pacemaker, does not keep a regular heartbeat.

People with SSS may have bradycardia, a slow heart rate of less than 60 beats per minute, or tachycardia, when the heart produces more than 100 beats per minute. Some may also have a combination of both.

There are other terms that a person may use to refer to SSS, including:

  • bradycardia-tachycardia syndrome
  • tachy-brady syndrome
  • sinus-node dysfunction

This heart condition can develop at any age, but it tends to affect older adults. The mean average age of people with SSS is 68 years.

This article explores the symptoms that may appear with SSS, the causes, and the risk factors. It also discusses possible complications, diagnostic tests, and what type of treatment doctors can recommend.

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SSS can cause various symptoms, these include:

At first, people with SSS may not experience any symptoms. However, when symptoms start developing, doctors associate them with hypoperfusion — a reduced amount of blood flow — and organs no longer receive enough oxygen.

People with tachycardia, referring to fast heartbeat episodes, may also experience palpitations, worsening symptoms of angina, and congestive heart failure.

As people age, their sinus node tissue can thicken or scar, disrupting its electrical impulses. This is the most common cause of SSS.

However, other factors can cause or contribute to SSS, such as receiving damage to the sinus node.

Health conditions that can damage the sinus node include:

Furthermore, the sinus node can sustain damage during heart surgery. Medications, such as beta-blockers, calcium-channel blockers, and digoxin, can also affect the sinus node.

Age is the primary risk factor for SSS. A 2021 study also suggests that atrial fibrillation contributes to SSS.

Atrial fibrillation episodes may be common in people with sinus node dysfunction.

It is important to note that some health conditions can increase the likelihood of developing sinus node dysfunction:

People with sinus node problems may have to get a permanent pacemaker implant. There is no cure for SSS, and without a pacemaker, a person may experience hypotension and fainting.

Pacemaker implantation comes with risks, including:

Medical professionals may use the following to make a diagnosis if they suspect SSS:

  • Electrocardiogram (ECG): An ECG checks the heart’s rhythm and electrical activity.
  • Remote cardiac monitoring: A device monitors the heart’s activity for 24 hours. These devices, such as a Holter monitor or event monitor, can tell if a person has an irregular heartbeat. They can also help doctors check if there are any problems in those who have a pacemaker.
  • Electrophysiologic study: Specialized cardiologists will insert tiny electrodes through veins into the heart using a catheter to diagnose specific arrhythmias.
  • Heart ultrasound: A cardiac ultrasound or echocardiogram can help assess the heart’s function and structures.

Identifying the factors causing or worsening sinus node dysfunction can help doctors determine the best treatment option.

For example, if a person is taking calcium-channel blockers or beta-blockers, a healthcare professional may recommend stopping them if possible, as they can affect the sinus node.

Doctors may also recommend a pacemaker, especially if they have bradycardia symptoms. Pacemakers can take over the role of the sinus node to prevent bradycardia. Cardiologists implant it under the skin on the chest.

Most SSS cases occur as a result of the aging sinus node. So, people do not have a lot of control over preventing the condition from occurring.

There are some tips that a person may follow to help reduce their risk of developing heart problems, including:

  • quitting smoking, if applicable
  • exercising
  • learning how to manage stress
  • following a healthy diet
  • managing blood pressure and cholesterol levels

The Centers for Disease Control and Prevention (CDC) claims that those who do not control high blood pressure may have a higher risk of developing a stroke, kidney disease, and pregnancy complications.

The CDC also recommends eating fruits and vegetables, reducing alcohol consumption, and following a doctor’s directions when taking medications.

Everyone can benefit from a discussion on preventing heart disease with their doctor. Additionally, people with the following risk factors should discuss them with their doctor:

  • smoking
  • low levels of physical activity
  • high blood pressure and diabetes
  • family history of heart disease

Additionally, the AHA advises seeking emergency medical care if a person has symptoms of a heart attack, stroke, or cardiac arrest, such as:

  • chest discomfort
  • shortness of breath
  • arm weakness
  • slurred speech
  • lightheadedness
  • unresponsiveness
  • facial drooping

SSS can progress over the years, and it may not always produce symptoms.

Complications can arise, and people may experience hypotension or fainting.

The outlook for SSS is good, and pacemaker implantation can help control symptoms.

SSS, or sinus node dysfunction, is a condition that causes the heart to beat slower or faster than usual.

The condition develops due to the degeneration of the heart’s conduction system due to aging, atrial fibrillation, and heart failure.

A pacemaker can reduce symptoms in persons with SSS, as without treatment, complications may be possible.

People should call a doctor or the emergency department if symptoms of stroke, cardiac arrest, or heart disease appear, including slurred speech, chest pain, or shortness of breath.