Heart conditions in children are more common than many parents realize. They range from defects present at birth to infections and rhythm problems that develop over time. The good news is that advances in medicine mean most children with heart conditions can live full, active lives. This guide explains the main types, what symptoms to watch for, and when to talk to your family doctor.

What Are Heart Conditions in Children?

Heart conditions in children cover a wide range of problems. Some affect the structure of the heart. Others affect how it beats or how well it fights off infection.

In some cases, symptoms appear right after birth. In others, a problem may go unnoticed until a child is older and more active. Either way, early diagnosis makes a big difference.

Doctors use several tools to diagnose these conditions, including:

  • Echocardiogram — an ultrasound of the heart

  • Electrocardiogram (ECG) — measures the heart’s electrical activity

  • Chest X-ray

  • Pulse oximetry — checks oxygen levels in the blood

  • Cardiac catheterization — a more detailed procedure using a thin tube

  • MRI (magnetic resonance imaging)

Your child’s doctor will choose the right test based on their symptoms and age. Many of these tests are available through your provincial health plan.

Congenital Heart Defects

Congenital heart defects are structural problems with the heart that are present at birth. They are the most common type of heart condition in children, affecting about 1 in 100 babies born in Canada. According to Health Canada, congenital heart defects are among the most frequently occurring birth defects.

Some defects are mild and close on their own. Others are more serious and require surgery, sometimes over several years. In the most severe cases, a child may need a heart transplant and lifelong follow-up care.

Common Types of Congenital Heart Defects

There are many types of congenital defects. Some of the most well-known include:

  • Atrial septal defect (ASD) — a hole between the upper chambers of the heart

  • Ventricular septal defect (VSD) — a hole between the lower chambers

  • Coarctation of the aorta — a narrowing of the main artery leaving the heart

  • Pulmonary valve stenosis — a narrowing of the valve that controls blood flow to the lungs

  • Patent ductus arteriosus (PDA) — a blood vessel that fails to close after birth

  • Tetralogy of Fallot — a combination of four heart defects

  • Transposition of the great arteries — the two main arteries are switched

  • Ebstein’s anomaly — a problem with the heart’s tricuspid valve

Symptoms of Congenital Heart Defects

Serious defects often show symptoms shortly after birth. Parents may notice:

  • Blue or grey tinge to the lips or skin (cyanosis)

  • Rapid breathing

  • Sweating during feeding

  • Swelling in the legs, belly, or around the eyes

  • Difficulty breathing or pauses in breathing while feeding

Milder defects may not cause symptoms until later in childhood. In those cases, a child might get short of breath during exercise, feel unusually tired, or faint.

Risk Factors and Causes

The exact causes of most congenital heart defects are not fully known. However, certain factors during pregnancy can raise the risk. These include:

  • Rubella (German measles) infection during pregnancy

  • Diabetes in the mother (not gestational diabetes)

  • Taking certain medications during pregnancy, such as statins, thalidomide, or ACE inhibitors

  • Smoking or drinking alcohol during pregnancy

If you are pregnant and have concerns, speak with your obstetrician or midwife as soon as possible.

Treatment Options

Treatment depends on the type and severity of the defect. Milder cases may only need monitoring. More serious cases may need medication, catheter-based procedures, or open-heart surgery. Your child’s care team will guide your family through the best options.

Heart Arrhythmias in Children

An arrhythmia is an abnormal heart rhythm. The heart may beat too fast, too slow, or unevenly. As a result, it may not pump blood as well as it should.

Arrhythmias are another important category of heart conditions in children. Some are harmless. Others need medical attention. The Mayo Clinic offers helpful detail on the different types of arrhythmias and how they are managed.

Common Types of Arrhythmias in Kids

  • Supraventricular tachycardia (SVT) — a fast heart rate starting above the lower chambers

  • Bradycardia — a heart rate that is too slow

  • Long QT syndrome — an electrical problem that can cause sudden fainting or cardiac arrest

  • Wolff-Parkinson-White syndrome — an extra electrical pathway in the heart that causes rapid beats

Symptoms to Watch For

Symptoms of an arrhythmia in a child can include:

  • Weakness or unusual fatigue

  • Dizziness

  • Fainting or near-fainting

  • Difficulty feeding (in infants) or unexplained weight loss

  • A pounding or fluttering feeling in the chest

Treatment depends on the type of arrhythmia and how much it affects the child’s health and daily life. Options range from medication to minor procedures.

Atherosclerosis: Not Just an Adult Problem

Atherosclerosis is the build-up of fatty plaques inside the arteries. Over time, the arteries become stiff and narrow. This raises the risk of blood clots.

Most people think of this as an adult condition, and it usually is. However, children with obesity, type 2 diabetes, high blood pressure, or a strong family history of heart disease may be at risk earlier than expected.

Doctors recommend checking children’s cholesterol and blood pressure regularly, especially if there is a family history of heart disease or diabetes. Early lifestyle changes can make a real difference.

Treatment focuses on healthier habits. This means more physical activity and a balanced diet with less fast food, chips, and sugary foods. In some cases, medication may also be needed.

Pericarditis and Viral Heart Infections

Pericarditis

Pericarditis is inflammation or infection of the pericardium — the thin sac surrounding the heart. When fluid builds up in this sac, it can affect the heart’s ability to pump blood properly.

In children, pericarditis can happen after heart surgery, after a bacterial infection, following chest trauma, or as a complication of conditions like lupus. Treatment depends on the cause, the child’s age, and their overall health.

Viral Infections and the Heart

Viruses can do more than cause colds and flu. They can also infect the heart muscle itself — a condition called myocarditis. Myocarditis reduces the heart’s ability to pump blood effectively.

This condition is rare, but it is worth knowing about. Symptoms can look like the flu and may include fatigue, shortness of breath, and chest discomfort. Treatment focuses on relieving symptoms and supporting the heart while it heals.

Rheumatic Heart Disease

Rheumatic heart disease is a serious complication of untreated strep throat or scarlet fever. When a streptococcal infection is not treated with antibiotics, the body’s immune response can damage the heart valves and muscle. This damage can be permanent.

Rheumatic fever most often affects children between the ages of 5 and 15. In some cases, the disease causes no obvious symptoms at first, which makes early treatment of strep infections especially important.

If your child has a sore throat that lasts more than a few days, or is accompanied by fever, see a doctor promptly. A simple throat swab can detect strep. The World Health Organization notes that rheumatic heart disease remains a leading cause of preventable heart disease in children worldwide.

When to See a Doctor

Trust your instincts as a parent. If something feels off, it is always worth getting it checked.

Contact your family doctor or visit a walk-in clinic if your child shows any of the following:

  • Bluish or greyish colouring around the lips or fingernails

  • Unusual shortness of breath during normal activity or feeding

  • Fainting or dizziness

  • Chest pain or a racing heartbeat

  • Extreme fatigue that seems out of proportion to their activity level

  • Poor weight gain or feeding difficulties in infants

If your child collapses, loses consciousness, or has severe trouble breathing, call 9-1-1 immediately. These symptoms require emergency care, not a walk-in clinic visit.

For ongoing concerns, your family doctor can refer your child to a pediatric cardiologist — a heart specialist for children. Many provinces cover this through their public health insurance plans.

Frequently Asked Questions

What are the most common heart conditions in children?

The most common heart conditions in children are congenital heart defects, which are structural problems present at birth. Arrhythmias, or abnormal heart rhythms, are also fairly common in kids. Less frequently, children can develop conditions like myocarditis, pericarditis, or rheumatic heart disease.

Can children outgrow heart defects?

Some mild heart defects, such as small ventricular septal defects, do close on their own as a child grows. However, many heart conditions in children require ongoing monitoring or treatment. Your child’s cardiologist will track the defect over time and recommend the right course of action.

What does a heart murmur in a child mean?

A heart murmur is an extra sound the doctor hears when listening to the heart. Many children have what are called “innocent” murmurs, which are harmless and require no treatment. However, some murmurs can signal an underlying heart condition in a child, so a doctor should always evaluate them properly.

How is a congenital heart defect diagnosed in Canada?

In Canada, many congenital heart defects are first detected through routine prenatal ultrasounds or newborn screenings in hospital. If a problem is suspected, a pediatric cardiologist will use tests like an echocardiogram or ECG to confirm the diagnosis. Most of these diagnostic tests are covered under provincial health insurance plans.

Can stress or exercise trigger heart problems in children?

For most healthy children, exercise is safe and beneficial. However, in children with certain heart conditions — such as Long QT syndrome or hypertrophic cardiomyopathy — intense physical activity can sometimes trigger dangerous arrhythmias. Always let your child’s doctor know about any symptoms like fainting or chest pain that occur during exercise.

Is rheumatic heart disease preventable?

Yes — rheumatic heart disease is largely preventable. It develops when strep throat or scarlet fever goes untreated, so getting a prompt diagnosis and completing a full course of antibiotics is key. If your child has a persistent sore throat and fever, visit your family doctor or a walk-in clinic for a throat swab.

Key Takeaways

  • Heart conditions in children include congenital defects, arrhythmias, infections, and inflammatory conditions.

  • Some conditions are present at birth; others develop over time or as complications of other illnesses.

  • Symptoms like bluish skin, fainting, unusual fatigue, or breathing difficulty in a child always deserve medical attention.

  • Many heart conditions are treatable, and children can go on to live healthy, active lives with the right care.

  • Rheumatic heart disease is preventable — treat strep infections early and completely.

  • Your family doctor is your first point of contact. They can refer your child to a pediatric cardiologist if needed, with costs covered under most provincial health plans.

  • Always consult a qualified healthcare provider for any concerns about your child’s heart health. This article is for general information only and is not a substitute for professional medical advice.