Read on for details about breathing and the different parts of your child's respiratory system.

Epiglottitis is a medical emergency. It's an infection of the epiglottis, the small flap of tissue that covers the windpipe (trachea). This condition causes swelling that may close off the airway and make it hard to breathe. If not treated quickly, it can be fatal.

Whooping cough (pertussis) is a bacterial infection of the respiratory tract. It is highly contagious and spreads easily from person to person through droplets when an infected person coughs, sneezes, or talks.

Tetralogy of Fallot is a congenital heart defect involving 4 different heart defects. Surgery can help treat this condition.

Learn how the heart works.

Your child just had surgery to treat a heart problem. The surgeon made an incision down the chest or breastbone or between the ribs. Here are general guidelines to care for your child at home.

Your child needs surgery to treat a heart problem. This sheet will help you and your child get ready for the surgery.

The heart makes sounds as the heart valves open and close to allow blood to flow through the heart. When blood does not flow smoothly through the heart or heart valves, it causes the noise. This is called turbulence. Heart murmurs can be harmless (innocent) or caused by a heart problem (pathologic).

Catheter ablation is a way to treat a tachycardia. This is an abnormal heart rhythm (arrhythmia) in which the heart beats too fast.

An arrhythmia can cause your child's heart to pump blood less efficiently. Many arrhythmias are harmless and don't need to be treated. But if it causes symptoms, it may need treatment.