Sick Sinus Syndrome

Sick sinus syndrome (sinus node dysfunction) is a heart rhythm condition that happens because your sinoatrial node (SA node) isn’t working right. When this pacemaker-like node can’t keep a steady beat, your heartbeat may be too slow (bradycardia). It can also switch between too fast and too slow (tachy-brady syndrome).

You may also have a sinus pause or arrest. This means your SA node isn’t sending any impulses for at least three seconds. Another part of your heart steps in to send a signal when this happens. But when it doesn’t, you can feel faint or lose consciousness.

Sick sinus syndrome isn’t common. American providers diagnosed 78,000 new cases in 2012 but expect to see 172,000 new cases in 2060.

Symptoms of sick sinus syndrome

Often, especially at the start of the disease, people with sick sinus syndrome have no symptoms. If they do have symptoms from a slow or fast heart rate, they include:

• Fainting
• Chest pain
• Lightheadedness or dizziness
• Heart palpitations
• Fatigue, especially during physical activity
• Shortness of breath, especially when you’re active
• Low urine output (less pee than usual)
• Belly pain

Sick sinus syndrome causes

SA node dysfunction has several causes. Sometimes, healthcare providers don’t know the cause.

Known causes of sick sinus syndrome include:

• Breakdown of your heart’s electrical route or SA node due to aging (most common)
• Injury to your SA node after heart surgery
• Some medicines for high blood pressure, abnormal heart rhythms (arrhythmias) or bipolar disorder
• Congenital disorders (present at birth)
• Metabolic problems, like high or low potassium
• Heart issues like heart failure, heart attack, cardiomyopathy or arrhythmias
• Conditions that infiltrate (invade) your heart, like sarcoidosis, amyloidosis or cancer that has spread

Risk factors

You’re more likely to get sick sinus syndrome if you:

• Are age 70 or older
• Had heart surgery
• Take medicines like beta-blockers, calcium channel blockers or certain antiarrhythmic medicines
• Had other inflammatory diseases like rheumatic fever or sarcoidosis
• Have certain genetic variants
• Have diabetes or high blood pressure

How to lower your risk

Although you can’t control risk factors like your genetics or your age, there are some things you can do to reduce your risk of sinus node dysfunction. You can take care of your heart to prevent heart disease. You can also keep your follow-up appointments for other health conditions that could put you at risk. When you talk with your healthcare provider, ask them if the medicines you take put you at risk.

Complications of this condition

Other problems that can happen if you have sick sinus syndrome include:

• Heart failure
• Fainting (and possibly getting hurt while fainting)
• Less of an ability to exercise
• Blood clots

How doctors diagnose this condition

To make a sick sinus syndrome diagnosis, your healthcare provider will do a physical exam and ask about your medical history. They’ll want to make sure you don’t:

• Have a lack of essential minerals (electrolytes)
• Have sleep apnea
• Take certain heart medicines that can cause problems with your SA node
• Have a problem with how your body handles its chemical reactions

Your provider will need to see a definite link between your symptoms and a slow heart rate (bradycardia) to diagnose SA node dysfunction.

Before making a diagnosis, your provider may order one or more of these:

• Blood tests
• Electrocardiogram (EKG)
• Heart rhythm monitors you wear at home
• Electrophysiology study (EP study)
• Stress test

How is it treated?

If you don’t have symptoms, you might not need any sick sinus syndrome treatment. If a medication caused the SSS heart problem, your treatment may include a prescription change. Or you may need treatment for an issue a healthcare provider can reverse, like a metabolic condition. Depending on your symptoms, you may need medicine or a pacemaker.

Treatments may include one or more of these:

• Permanent pacemaker for a slow heart rate that causes symptoms like dizziness, fatigue or fainting
• Medicine for arrhythmias, since certain ones (especially atrial fibrillation or AFib) can lead to tachy-brady syndrome

Recovery time

It may take several days to a week to recover from pacemaker surgery. You should recover completely in about a month.

When should I see my healthcare provider?

Contact your provider if you have sick sinus syndrome symptoms or if you have a problem with your pacemaker. Get emergency care if you have fainting spells. You should have follow-up visits with your provider for the long term if you have a pacemaker.

You may want to ask your healthcare provider:

• Do you know the cause of my case of sick sinus syndrome?
• Will I need a pacemaker?
• How often will I need checkups if I get a pacemaker?

What can I expect if I have this condition?

Sick sinus syndrome usually keeps getting worse over many years. But some people never end up with other health issues connected to this condition. A pacemaker can help relieve your symptoms and give you a better quality of life, but it may not extend your life expectancy.

Can I exercise with sick sinus syndrome?

You can be physically active with this condition, but it may be difficult. Once you get a pacemaker, physical activity should be easier.

How long does sick sinus syndrome last?

Sick sinus syndrome is a long-term problem that slowly gets worse.

What is the outlook for sick sinus syndrome?

Getting a pacemaker gives you a great outlook. There’s only a low risk of sudden cardiac death with sick sinus syndrome. Having other heart issues along with sinus node dysfunction can give you a worse prognosis.

Is there anything I can do to feel better?

To feel your best, you can:

• Avoid certain medicines if your provider tells you to do so.
• Keep your follow-up appointments with your provider.
• Keep taking prescribed medicines as instructed.
• Follow your provider’s instructions for maintaining your pacemaker.