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Arrhythmia Diagnosis & Treatment for Children

Heart Arrhythmia in Children: Symptoms, Causes, Diagnosis & Treatments

An arrhythmia is an unusual heartbeat – too fast, too slow or irregular – that varies from the heart’s usual steady rhythm. Arrhythmias make it harder for the heart to pump enough blood to the rest of the body. An abnormal heartbeat in a child can cause symptoms such as heart palpitations, shortness of breath and dizziness.

At Pediatric Heart Specialists, our cardiologists have advanced training and years of experience in arrhythmia care for children. We’re experts at detecting the signs and symptoms of arrhythmias for an accurate diagnosis to plan personalized care for your child.

What is arrhythmia?

The heart’s electrical system controls heart rate and rhythm by sending electrical signals through the heart muscle. These signals tell the heart to squeeze and relax to pump blood, creating a heart rhythm. An arrhythmia is an unusually fast, slow, or irregular heart rhythm.

If the signals don’t travel through the heart as they should, the heart can’t work properly. With a fast arrhythmia, the heart’s chambers can’t relax enough to fill with blood. A slow or irregular heart rate prevents the chambers from contracting enough to pump blood from the heart to the body. With arrhythmias, the brain and other organs can’t work well and may become damaged.

What is a normal heart rate for a child?

Heart rates in children vary based on their age, size, fitness and other factors. Our pediatric cardiologists can determine whether your child’s heart rate is too fast or too slow during our evaluation for diagnosis.

What types of arrhythmia occur in children?

Premature heartbeats (contractions)

Premature contractions occur when a heart chamber squeezes (contracts) earlier than it should. It may feel like an extra or a skipped heartbeat, causing a feeling of fluttering or pounding.

Premature heartbeats are common in children and teens, and they’re usually harmless. The two types are:

  • Premature atrial contractions (PACs), which are extra heartbeats that come from an upper chamber (atrium)
  • Premature ventricular contractions (PVCs) in the lower chambers (ventricles)

Fast heart rhythms (tachycardia)

Heart rates that are too fast are called tachycardias:

  • Supraventricular tachycardia (SVT): The most common arrhythmia in children, an SVT begins in the upper chambers. It’s a sudden, fast heart rhythm that may last from a few seconds to several hours.
  • Ventricular tachycardia (VT): VT is a fast heart rate that starts in the lower chambers and can become dangerous.
  • Ventricular fibrillation (VFib): VFib occurs when the lower chambers beat extremely fast and erratically, causing them to quiver rather than squeeze. With VFib, the heart cannot pump blood to the body, causing a life-threatening emergency that requires immediate medical care.

Slow heart rhythms (bradycardia)

Bradycardias are heart rhythms that are too slow. This type of arrhythmia is very rare in children and includes:

  • Sick sinus syndrome: The heart’s natural pacemaker, the sinus node, controls the electric signals that trigger heartbeats. If the sinus node doesn't work as it should, it can cause both slow and fast heart rates.
  • Complete heart block: This slow heartbeat results from a delay or total blockage in electrical signals from the upper to lower chambers.
  • Respiratory sinus arrhythmia:In some children, their heart rhythm speeds up when they breathe in and slows when they breathe out.

Sinus arrhythmias

Sinus arrhythmias, which begin in the sinus node, are not harmful and usually don’t require treatment. You or your child may notice a faster or slower heartbeat, but there’s no need to worry about it. Sinus arrhythmias occur more often in children, and they usually go away on their own as your child gets older. The types of sinus arrhythmia include:

  • Sinus tachycardia: This heart rhythm is a bit faster, usually in response to fear, activity, pain, caffeine, medicine or other causes.
  • Sinus bradycardia: This slower heart rate usually occurs in children during sleep or children who are active on a regular basis.
  • Respiratory sinus arrhythmia: In some children, their heart rhythm speeds up when they breathe in and slows when they breathe out.

Arrhythmia symptoms and signs in children

The signs and symptoms of arrhythmia can vary depending on your child’s age. You may notice unusual tiredness, shortness of breath, poor feeding, sweating with feeding or other signs in your infant or toddler. An older child may be complaining of chest pain, fast heartbeat and other symptoms.

Pediatric arrhythmia symptoms can resemble those of other, less serious health conditions. It’s important that your child sees an experienced pediatric cardiologist for an evaluation if they have any of these symptoms:

  • Weakness and fatigue (tiredness)
  • Heart palpitations (a feeling of the heart racing or pounding)
  • Dizziness and lightheadedness
  • Shortness of breath
  • Fainting (syncope)
  • Poor appetite (children) and difficulty feeding (infants)
  • Chest pain

Causes of arrhythmia in children

Sometimes, the causes of arrhythmia in a child are unknown. Some known causes include:

  • Congenital (present at birth) heart diseases that affect the heart’s electrical system or structure
  • Inherited heart conditions, such as hypertrophic cardiomyopathy (unusually thick heart muscle)
  • High fever or myocarditis, inflammation in the heart muscle
  • Scar tissue that can develop after heart surgery

Cardiac arrhythmia diagnosis in children

At PHS, our pediatric cardiologists begin with a thorough evaluation, asking about your child’s symptoms, their medical history and your family’s medical history. We do a physical exam and an electrocardiogram (EKG/ECG) , a painless test to measure the electrical activity in your child’s heart.

To confirm a cardiac arrhythmia diagnosis, we may recommend other tests, including:

  • Echocardiogram (echo): This imaging test, a heart ultrasound, uses sound waves to create detailed pictures of the heart. We use an echocardiogram to examine heart chambers, walls and valves to see how well the heart pumps blood.
  • Holter monitor: This tiny, portable EKG device records your child’s heart rhythm during their everyday activities. A Holter monitor is a painless test that can last for periods from 24 hours to 14 days, capturing heart rhythms that a regular EKG might miss.
  • Cardiac event monitor: Similar to a Holter monitor, this device is a small, portable EKG machine. Your child may wear a cardiac event monitor for up to 30 days to record heart rhythms that occur only a few times a month.
  • Stress test: If your child’s symptoms happen only when they’re active, we may recommend a stress test . Your child exercises while attached to an EKG to record heartbeats during an increasing activity level.

If we diagnose your child with an arrhythmia that may have a genetic factor, we may recommend genetic testing. Genetic testing can show whether specific gene mutations are causing the arrhythmia. If so, we can also screen for the mutations in other family members, who can then decide on preventive heart care or treatments.

Pediatric arrhythmia treatment

Many arrhythmias in children, such as sinus arrhythmias, are normal or harmless and don’t need treatment. Sometimes, an arrhythmia needs treatment. Often, we treat the underlying cause of the arrhythmia, and the arrhythmia goes away.

Pediatric arrhythmia treatment options vary depending on your child’s age, the type of arrhythmia and how severe the arrhythmia and its symptoms are. Our pediatric cardiologists can successfully treat the most serious arrhythmias. At PHS, we develop a personalized treatment plan, working closely with you to decide on the right care for your child.

Medications to treat arrhythmia in children

In most cases, we begin with medications to slow a fast heart rate or stabilize an irregular heart rhythm. Medications for pediatric arrhythmia treatment include beta blockers, calcium channel blockers and antiarrhythmic medications.

Our pediatric cardiologists are experienced in choosing effective medications for your child. We closely monitor your child to check for side effects and adjust the dosage as they grow.

Surgery and cardiac catheterization for pediatric arrhythmia

In the rare cases when medications haven’t been successful, we may recommend a procedure. We refer your child to pediatric heart specialists at The Heart Center at Children’s Health or another hospital near you for a procedure. We coordinate the arrangements, providing a seamless process for you and your family. Your child comes back to us afterward for follow-up visits and ongoing care.

Procedures to treat pediatric arrhythmia include:

  • Electrophysiology (EP) study: Minimally invasive cardiac catheterization uses catheters (thin, flexible tubes) to access the heart from a blood vessel. Cardiologists use EP studies to find areas where arrhythmias begin. They can do an ablation during the same procedure.
  • Catheter ablation: During an EP study, cardiologists use heat (radiofrequency ablation) or cold (cryoablation) energy to treat small areas where an arrhythmia starts. Ablation can treat most types of arrhythmia in children.
  • Pacemaker: For a slow heart rate that requires treatment, a pacemaker sends mild electrical pulses to stimulate the heart to beat faster. A pacemaker is a small device placed under the skin of your child’s chest.
  • Implantable cardioverter-defibrillator (ICD): Although very rare, some children can have a potentially life-threatening arrhythmia. In some of these cases, the child may need an ICD. An ICD is a small, implanted device that monitors your child’s heart rate. The device sends small electrical pulses to slow a fast heart rate and a larger shock when it detects a life-threatening irregular rhythm.
  • Heart surgery: Heart surgeons may treat pediatric arrhythmia during surgery for another heart condition. It’s very rare for a child to need heart surgery for an arrhythmia. It would be done only when other treatments have not been able to control arrhythmia or if a child has arrhythmia after multiple heart surgeries.