Congenital Heart Defects
A congenital heart defect is a problem with the structure of the heart. It is present at birth. Congenital heart defects are the most common type of birth defect. The defects can involve the walls of the heart, the valves of the heart, and the arteries and veins near the heart. They can disrupt the normal flow of blood through the heart. The blood flow can slow down, can go in the wrong direction or to the wrong place, or can be blocked completely. Doctors use a physical exam and special heart tests to diagnose congenital heart defects. They often find severe defects during pregnancy or soon after birth. Signs and symptoms of severe defects in newborns include: - Rapid breathing. - Cyanosis - a bluish tint to the skin, lips and fingernails. - Fatigue. - Poor blood circulation. Many congenital heart defects cause few or no signs and symptoms. They are often not diagnosed until children are older. Many children with congenital heart defects do not need treatment, but others do. Treatment can include medicines, catheter procedures, surgery and heart transplants. The treatment depends on the type of the defect, how severe it is, and the child's age, size and general health.
INTRODUCTION
A congenital heart defect is a problem with the structure of the heart. It is present at birth. Congenital heart defects are the most common type of birth defect. Severe defects are often found during pregnancy or soon after birth. Many congenital heart defects are not diagnosed until children are older. Treatment can include medicines, medical procedures and surgery. This health information explains congenital heart defects. It covers symptoms and causes of congenital heart defects. It also talks about the diagnosis and treatment of these types of defects.
THE HEART
The main function of the heart is to pump blood to the lungs and the rest of the body. Two main compartments form the heart. These compartments are called the right heart and the left heart. Each compartment has two chambers: a smaller chamber called an atrium and a bigger chamber called a ventricle. The ventricles are the main pumps of the heart. The septum is the wall that separates the chambers on the left and right sides of the heart. Blood comes from the body to the heart through two big veins. This blood enters the right atrium. It is then pumped into the right ventricle through a valve known as the tricuspid valve. The blood is then pumped into the lungs through the pulmonary valve. In the lungs, the blood is loaded with oxygen. It then returns to the left side of the heart, to the left atrium. Next, the blood is pumped into the left ventricle through the mitral valve. The left ventricle pumps the blood to the rest of the body through the aortic valve.
TYPES OF CONGENITAL HEART DEFECTS
Congenital heart defects change the normal flow of blood through the heart. They can affect the:
• Arteries and veins that carry blood to the heart or the body.
• Interior walls of the heart.
• Valves inside the heart.
There are many types of congenital heart defects. Some are simple defects with no symptoms. Others are complex defects with life threatening symptoms. Some simple congenital heart defects are:
• Holes between different chambers in the heart.
• Patent ductus arteriosus, or PDA.
• Narrowed valves.
Some babies are born with holes in the septum, which is the wall that separates the chambers on the left and right sides of the heart. Blood mixes between the two sides of the heart through the holes. Holes in the heart may be small, medium or large. Large holes allow more blood to leak through and may cause more severe symptoms. Large holes may even lead to heart failure. In patent ductus arteriosus, or PDA, abnormal blood flow happens between the aorta and the pulmonary artery. Before birth, the aorta and pulmonary artery are connected by a blood vessel called the ductus arteriosus. Within minutes or up to a few days after birth, the ductus arteriosus closes. In some babies, though, the ductus arteriosus remains open. The opening allows blood from the aorta to mix with blood from the pulmonary artery. This can strain the heart. Simple congenital heart defects also can involve the heart's valves. Normally, these valves control blood flow through your heart and prevent blood from flowing backward. Heart valves can have three basic kinds of problems:
• Regurgitation.
• Stenosis.
• Atresia.
Complex congenital heart defects can cause more severe symptoms. These types of defects can be life threatening. One example of a complex congenital heart defect is tetralogy of Fallot. It is the most common complex heart defect. In tetralogy of Fallot, not enough blood is able to reach the lungs to get oxygen. This means that oxygen-poor blood flows to the body.
CAUSES
With congenital heart defects, some part of the heart does not form properly before birth. This changes the normal flow of blood through the heart. The blood flow can slow down, go in the wrong direction or to the wrong place or be blocked completely. The causes of congenital heart defects are often unknown. More research needs to be done to understand why congenital heart defects happen. Heredity may play a role in some heart defects. This means that a parent who has a congenital heart defect may be more likely to have a child with the defect. Children who have genetic disorders often have congenital heart defects. One example of a genetic disorder is Down syndrome. Half of all babies who have Down syndrome have congenital heart defects. Smoking during pregnancy also has been linked to several congenital heart defects, including holes in the septum.
SYMPTOMS
Some congenital heart defects may not cause any symptoms. If symptoms are present, they may include:
• Extreme tiredness.
• Poor blood circulation.
• Rapid breathing.
Another possible symptom is cyanosis. Cyanosis is a bluish tint to the skin, lips and fingernails. It happens because the oxygen level in the blood leaving the heart and going to the rest of the body is below normal. Heart defects can also cause heart murmurs. Heart murmurs are unusual sounds heard during a heartbeat. Not all heart murmurs are a sign of a heart defect. Healthy children may have heart murmurs. Babies who have congenital heart defects may tire easily while feeding. As a result, they may not gain weight or grow as they should. Older children who have congenital heart defects may get tired easily or get short of breath during physical activity. Severe defects can lead to heart failure. Symptoms of heart failure include:
• A buildup of blood and fluid in the lungs.
• Shortness of breath or trouble breathing.
• Swelling in the ankles, feet, legs, abdomen and veins in the neck.
DIAGNOSIS
Severe congenital heart defects are often diagnosed during pregnancy or soon after birth using an ultrasound. Less severe defects may not be diagnosed until children are older. Your child’s health care provider will ask you about your child’s medical history and symptoms. A physical exam will be performed. During a physical exam, the health care provider will:
• Listen to your child's heart and lungs.
• Look for signs of a heart defect, such as shortness of breath or a bluish tint to the skin.
Tests may be done to help diagnose a congenital heart defect. These may include:
• Echocardiography, or echo.
• Electrocardiogram, or EKG.
• Chest x-ray.
• Pulse oximetry.
• Cardiac catheterization.
TREATMENT
Some children with congenital heart defects do not require treatment. If treatment is needed, it may include:
• Medicines.
• Catheter procedures.
• Surgery.
Medicines may be used to:
• Prevent problems.
• Relieve symptoms.
• Treat complications.
Medicines are often given to children until a heart defect can be fixed. Sometimes medicines are needed after a defect is repaired. Certain defects may require taking medicines for a long time. Catheter procedures involve a needle puncture in the skin where the catheter is inserted into a vein or an artery. A catheter is a thin, flexible tube. The type of catheter procedure done depends on the defect being repaired. If the defect is a hole in the septum, an umbrella-like device is pushed out of the catheter. The device is placed so that it plugs the hole. Within 6 months, normal tissue grows in and over the device. To treat stenosis, a tiny balloon at the end of the catheter is quickly inflated to push open and stretch the narrowed valve. Then, the balloon is deflated and the catheter and balloon are withdrawn. Open-heart surgery may be needed if a defect cannot be fixed with a catheter procedure. Sometimes one surgery can repair the defect completely. In other cases, multiple surgeries may be needed over months or years. Rarely, a heart defect may be too complex to fix. In these cases, a heart transplant may be needed. In this procedure, the child's heart is replaced with a healthy heart from a deceased child.
SUMMARY
A congenital heart defect is a problem with the structure of the heart. It is present at birth. Congenital heart defects are the most common type of birth defect. The cause of congenital heart defects is often unknown. There are many types of congenital heart defects. Some are simple defects with no symptoms. Others are complex defects with life threatening symptoms. Some simple congenital heart defects are:
• Holes in the heart.
• Patent ductus arteriosus, or PDA.
• Narrowed valves.
An example of a complex congenital heart defect is tetralogy of Fallot. Some congenital heart defects may not cause any symptoms. If symptoms are present, they may include:
• Extreme tiredness.
• Poor blood circulation.
• Rapid breathing.
Severe defects are often found during pregnancy or soon after birth. Many congenital heart defects are not diagnosed until children are older. Treatment can include medicines, medical procedures and surgery.
