Sinus Arrhythmia

While it may seem odd to call an abnormal heart rhythm a sign of a healthy heart, this is actually the case with sinus arrhythmia. Your heart beats at a different rate when you breathe in than when you breathe out. And it’s normal. If your heart doesn’t have sinus arrhythmia, it’s a reason for concern.


EKG showing sinus arrhythmia.
Time between heartbeats can vary when you breathe in and out.

What is sinus arrhythmia?

Sinus arrhythmia is a kind of arrhythmia (abnormal heart rhythm). For the most common type of sinus arrhythmia, the time between heartbeats can be slightly shorter or longer depending on whether you’re breathing in or out. Your heart rate increases when you breathe in and slows down when you breathe out. This kind of arrhythmia is considered normal. It’s usually a sign that your heart is healthy.


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What is the difference between sinus arrhythmia and other conditions?

Respiratory sinus arrhythmia is usually normal and doesn’t have symptoms, but the conditions below aren’t normal and do have symptoms.

Using EKG results, your provider will make sure you don’t have:

Who does sinus arrhythmia affect?

Providers see this a lot in healthy children and young adults.


How common is sinus arrhythmia?

It’s very common in young, healthy people. It’s actually a sign of good heart health.

How does sinus arrhythmia affect my body?

Usually, there are no symptoms.


Symptoms and Causes

What are the symptoms of sinus arrhythmia?

It’s rare for people to have symptoms of sinus arrhythmia.

What causes sinus arrhythmia?

Providers separate different kinds of sinus arrhythmia based on their causes.

Respiratory sinus arrhythmia

It’s normal to have respiratory sinus arrhythmia simply because you’re breathing. When you take a breath, your heart rate goes up. When you breathe out, it slows down.

The time between each heartbeat is known as the P-P interval. In most people, there’s a slight variation of less than 0.16 seconds. In cases of respiratory sinus arrhythmia, the P-P interval will often be longer than 0.16 seconds when the person breathes out.

Nonrespiratory sinus arrhythmia

In EKG results, nonrespiratory sinus arrhythmia can look like respiratory sinus arrhythmia. But people with this type usually:

  • Had a head or neck injury.
  • Took too much digoxin (Digitek®).
  • Have heart disease.

Ventriculophasic sinus arrhythmia

Providers can identify ventriculophasic sinus arrhythmia by looking at the electrocardiogram (EKG) results. People with this kind of sinus arrhythmia usually have third-degree AV block.

Diagnosis and Tests

How is sinus arrhythmia diagnosed?

Healthcare providers often find sinus arrhythmia while doing a routine electrocardiogram (EKG).

What tests will be done to diagnose sinus arrhythmia?

An electrocardiogram (EKG) can tell your provider if you have sinus arrhythmia.

Management and Treatment

How is sinus arrhythmia treated?

Since respiratory sinus arrhythmia is normal, people without symptoms rarely need treatment.

With nonrespiratory sinus arrhythmia or ventriculophasic sinus arrhythmia, generally, you don’t need any further testing or intervention.


How can I prevent sinus arrhythmia?

You can’t prevent respiratory sinus arrhythmia. And you don’t want to, because it’s a sign of a healthy heart.

Outlook / Prognosis

What can I expect if I have sinus arrhythmia?

If you have respiratory sinus arrhythmia, your outlook is good. You have a healthy heart.

Additional Common Questions

Is sinus arrhythmia dangerous?

No. Respiratory sinus arrhythmia is actually a sign of a healthy heart.

Can sinus arrhythmia cause chest pain?

No. Respiratory sinus arrhythmia doesn’t cause chest pain.

A note from Cleveland Clinic

You might be concerned when your healthcare provider notices an abnormal heart rhythm in your routine EKG. But respiratory sinus arrhythmia is not a cause for worry. The time between heartbeats can be different depending on whether you’re breathing in or out. So this “abnormal” rhythm is actually a sign of a heart that’s working right.

Medically Reviewed

Last reviewed on 03/21/2022.

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