Why do congenital heart defects occur

Some congenital heart defects in children are simple and don't need treatment. Other congenital heart defects in children are more complex and may require several surgeries performed over a period of several years. Learning about your child's congenital heart defect can help you understand the condition and know what you can expect in the coming months and years. Serious congenital heart defects usually are noticed soon after birth or during the first few months of life.

Signs and symptoms could include:. Less-serious congenital heart defects may not be diagnosed until later in childhood. Signs and symptoms of congenital heart defects in older children may include:. Serious congenital heart defects are often diagnosed before or soon after your child is born. If you notice that your baby has any of the signs or symptoms above, call your child's doctor. If your child has any of the signs or symptoms of less-serious heart defects as he or she grows, call your child's doctor.

Your child's doctor can let you know if your child's symptoms are due to a heart defect or another medical condition. A typical heart has two upper and two lower chambers. The upper chambers — the right and left atria — receive incoming blood. The lower chambers — the right and left ventricles — pump blood out of your heart. The heart valves, which keep blood flowing in the right direction, are gates at the chamber openings for the tricuspid and mitral valves and exits for the pulmonary and aortic valves.

To understand the causes of congenital heart defects, it may be helpful to know how the heart works. The heart is divided into four hollow chambers, two on the right and two on the left. To pump blood throughout the body, the heart uses its left and right sides for different tasks. The right side of the heart moves blood to the lungs through the lung pulmonary arteries. In the lungs, blood picks up oxygen then returns to the heart's left side through the pulmonary veins.

The left side of the heart then pumps the blood through the body's main artery aorta and out to the rest of the body. During the first six weeks of pregnancy, the heart begins to form and starts beating. The major blood vessels that run to and from the heart also begin to develop during this critical time.

It's at this point in your baby's development that heart defects may begin to develop. Researchers aren't sure exactly what causes most of these defects, but they think genetics, certain medical conditions, some medications, and environmental or lifestyle factors, such as smoking, may play a role.

There are many different types of congenital heart defects. They fall into the general categories described below. Abnormal connections allow blood to flow where it normally wouldn't. Holes in the walls between heart chambers are an example of congenital heart defects that involve an abnormal connection.

An abnormal connection can cause oxygen-poor blood to mix with oxygen-rich blood. This lowers the amount of oxygen sent through your child's body. Some illnesses a mother may have or medicines for these illnesses can affect the heart's growth. Other illnesses or medicines seem to have no effect on the baby's heart.

Always talk to your healthcare provider for more information. Counseling is important for women with chronic illnesses before becoming pregnant. Always talk to your healthcare provider before taking any medicines while you are pregnant. Rubella is known to cause birth defects.

Rubella is a virus that most people in the U. A woman who has never had rubella or the vaccine should talk with her healthcare provider before becoming pregnant. A mother who has rubella during her pregnancy has a very high chance of having a baby with birth defects, including CHD. Some heart defects have autosomal-dominant inheritance. Males and females are equally affected. Women with congenital heart defect should talk with a genetic counselor or genetic specialist before becoming pregnant.

In families with CHD in the parents or other children, talk with your healthcare provider about fetal echocardiography. This test can be done in the second trimester, as early as 16 weeks of pregnancy. It looks for major heart defects in the baby. Chromosomes are the structures in your cells that contain your genes. Genes contain the code for your traits such as eye color and blood type. Usually, there are 46 chromosomes in each cell of the body. Having too many or too few chromosomes leads to health problems and birth defects.

This condition is marked by these 4 defects:. A ventricular septal defect. This lets blood pass from the right ventricle to the left ventricle without going through the lungs. A narrowing stenosis at, or just under, the pulmonary valve. This partly blocks blood flow from the right ventricle to the lungs. Thickening or enlargement of the right ventricle. The aorta lies right over the ventricular septal defect called an overriding aorta.

Tetralogy of Fallot can cause a blue color of the skin and mucous membranes due to lack of oxygen cyanosis. Double outlet right ventricle DORV. Normally, the aorta connects to the left ventricle. With this complex condition, both the aorta and the pulmonary artery are connected to the right ventricle.

This causes oxygen-poor blood to circulate in the body. Truncus arteriosus. During a baby's normal development, the aorta and pulmonary artery start as 1 blood vessel.

Then the vessel divides into 2 separate arteries. Truncus arteriosus occurs when the single large vessel doesn't fully separate. This leaves a large connection between the aorta and the pulmonary artery. Some of the problems that cause too little blood to travel to the body include:. Coarctation of the aorta CoA.

In this condition, the aorta is narrowed or constricted. This blocks blood flow to the lower part of the body. And it increases blood pressure above the constriction. Often there are no symptoms at birth. But symptoms can occur as early as the first week of life. If there are severe symptoms of high blood pressure and congestive heart failure, surgery will be needed. Aortic stenosis AS. In AS, the aortic valve between the left ventricle and the aorta did not form correctly and is narrowed.

This makes it hard for the heart to pump blood to the body. A normal aortic valve has 3 leaflets cusps. But a stenotic valve may have only 1 cusp unicuspid or 2 cusps bicuspid. Aortic stenosis may not cause symptoms. But it may get worse over time. Surgery or a catheterization procedure may be needed to fix the blockage. Or the valve may need to be replaced with a manmade one. A complex combination of heart defects known as hypoplastic left heart syndrome can also occur. Hypoplastic left heart syndrome HLHS.

A combination of several abnormalities of the heart and the great blood vessels. In HLHS, most of the structures on the left side of the heart including the left ventricle, mitral valve, aorta, and aortic valve are small and underdeveloped. How underdeveloped they are will be different for each child. The left ventricle may not be able to pump enough blood to the body. HLHS is fatal without treatment. Babies with congenital heart problems are cared for by specialists called pediatric cardiologists.

These healthcare providers diagnose heart defects. And they help manage a child's health before and after surgery to fix the heart problem. Specialists who fix heart problems in the operating room are pediatric cardiovascular or cardiothoracic surgeons.

Today, people with congenital heart disease CHD are living longer. This improved survival rate is due to major advances in tests, treatments, and surgical methods. Children with CHD who reach adulthood must move transition from pediatric care to adult cardiac care.

This is vital if they are to reach and maintain the highest level of wellness. The type of care needed is based on the type of CHD a person has. Those with simple CHD can often be cared for by a community adult cardiologist. Adults with CHD have different needs and concerns than children. This is part of the successful move from pediatric care to adult care. This transition starts in your child's early teen years.

During this first phase, both you and your child's specialist should talk about your teen one day being responsible for their own care. This will depend on several factors, such as your child's ability to care for themselves. It's best to start talking about this when your child is fairly healthy. Your child will need to be able to: Talk in some detail about their condition List their medicines and when they take them Tell if their condition is changing or getting worse.

As a parent, you must help your young teen get ready to transition to adult cardiac care.