Arrhythmia is an irregular heart rhythm. The condition is usually not serious, but when it is, treatment is generally effective.

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It’s common for children to have changes in their heart rhythm. Their heart may speed up when they are actively playing or crying, or slow down when they are resting.

Sometimes a child’s heart rhythm becomes abnormal. It may be too fast, too slow, or has an atypical pattern. When this happens, it’s called arrhythmia.

Arrhythmias in children can be scary for parents, but they are treatable. Treatment helps children avoid any serious complications.

Here’s a look at arrhythmias in children, including different types, symptoms, causes, diagnosis, and treatment.

Arrhythmia happens when the heart beats in an abnormal way. This may include a heart rate that is sped up, slower than average, or irregular.

Several types of arrhythmias can occur in children. The most common types of arrhythmia in children include:

Respiratory sinus arrhythmia

This common arrhythmia in kids is usually nothing to worry about. It’s characterized by an irregular heart rate caused by a change in blood flow to the heart during breathing.

Premature heartbeats

Often described as the sensations of the heart “skipping a beat,” these are common and seen in about 75% of children. Premature heartbeats may occur in the top or bottom chambers of the heart.

Supraventricular tachycardia

Supraventricular tachycardia is the most common heart rhythm abnormality in children. About 50% of children receive a diagnosis as an infant and often outgrow it.

However, children who receive a diagnosis of supraventricular tachycardia when they are older are less likely to outgrow it. About 1 in 250 kids have this condition. Problems with the electrical signals in the heart causes it.

Wolff-Parkinson-White (WPW) syndrome

In this syndrome, a child has an additional electrical pathway in the heart, which causes the heart to beat faster than normal.

Atrial flutters and atrial fibrillation

These conditions are characterized by fluttering sensations in the heart and a fast, irregular heartbeat. They can increase a child’s risk of blood clots.

Ventricular tachycardia

This is when the heartbeat starts in the lower chambers of the heart rather than the top chambers, causing an abnormally fast heart rate. Ventricular tachycardia is rare but serious. It can increase the risk of heart attacks.


Bradycardia is an unusually slow heart rate. While there are several types of bradycardia, two types are more frequently seen in children:

  • Sinus bradycardia: Sinus bradycardia is more common in premature babies.
  • Heart block: Heart block happens when electrical signals can’t move from the heart’s upper chambers to the lower chambers.

Symptoms of arrhythmia in children vary depending on a child’s age and which particular condition is causing the irregular heart rhythm. Sometimes a child will not have any obvious symptoms.

Some possible symptoms of arrhythmia in children include:

  • fussiness, especially in babies
  • irritability
  • feeding problems
  • pale skin
  • decreased energy
  • dizziness
  • prone to fainting
  • experiencing heart palpitations or a fluttering heartbeat
  • shallow breathing
  • chest pain or pressure

There are several possible causes of arrhythmia in children.

Sometimes, variations in heart rate occur from stress and physical exertion. Other times, being sick, experiencing dehydration, or having a condition like anemia can contribute.

At times, medications your child is taking cause an arrhythmia to develop. Genetic conditions are also a common cause of arrhythmia in kids.

Genetics is a common risk factor for arrhythmia in children. Several kinds of arrhythmias result from inherited conditions that cause congenital heart defects. These defects can contribute to irregular heart functioning.

Most arrhythmias in children don’t cause complications. But some can be more serious, especially if left untreated. Complications vary based on the type of arrhythmia.

More common arrhythmia complications include:

  • Ventricular tachycardia: Ventricular tachycardia can increase the risk of heart attacks.
  • Atrial flutter and atrial fibrillation: Atrial flutter and atrial fibrillation may increase the likelihood of a blood clot.
  • WPW syndrome and Long OT Syndrome (LQTS). WPW syndrome and long QT syndrome (LQTS) may increase the risk of sudden cardiac-related death.

There are many effective treatments for children who have arrhythmia. Treatment depends on what’s causing your child’s arrhythmia.

Common treatments include:

  • Medications: A doctor may prescribe cardiac medication, such as beta-blockers, to help regulate your child’s heart rate.
  • Surgery: In some cases, surgery may be needed. A doctor can implant a cardioverter defibrillator (ICD), which is a device that keeps track of heart rate and delivers electric shocks to the heart if irregularities are detected.
  • Catheter ablation: During catheter ablation, radiofrequency energy is used to kill heart tissue that’s causing a fast or irregular heart rate.
  • Cardioversion: In cardioversion, delivering an electrical shock to your child’s heart can help return the heartbeat to a more typical rhythm.

Most arrhythmias in children are not harmful, and many kids outgrow them.

When children have serious heart conditions, a physician needs to address them. They can prescribe medication or recommend surgeries or other procedures. These treatments are effective and protect the child from severe outcomes.

If your child has signs or symptoms of arrhythmia or your pediatrician suspects it, they may run a series of tests to diagnose the conditions.

Typical tests used to diagnose arrhythmia are:

Do children have faster heartbeats than adults?

It’s typical for children, especially babies, to have faster heart rates than grownups.

According to the American Academy of Pediatrics, infants have a waking heart rate of 100–180 beats per minute. For a child who’s 6–7 years old, 75–118 beats per minute is typical.

What can parents do if their kids have arrhythmias?

The American Heart Association recommends parents learn:

  • how to check their child’s heart rate
  • techniques for slowing a fast heart rate
  • CPR

It’s also important for children to get regular checkups with their care team.

Which arrhythmias in kids are caused by genetics?

Types of arrhythmia caused by congenital heart defects include Wolff-Parkinson-White syndrome and long QT syndrome, a kind of ventricular tachycardia.

Learning that your child has an irregular heart rhythm can be scary. But arrhythmias in children are more common than you might think.

Most of the time, arrhythmias are not serious. Some even resolve as your child gets older. For arrhythmias that are more severe, treatment can ensure your child stays healthy.

If you have any questions or concerns about your child’s arrhythmia, don’t hesitate to contact their healthcare professional.