About congenital heart defects
What is congenital heart defects?
What are congenital heart defects?
Congenital (kon-JEN-ih-tal) heart defects are problems with the heart's structure that are present at birth. These defects can involve:
- The interior walls of the heart
- The valves inside the heart
- The arteries and veins that carry blood to the heart or the body
Congenital heart defects change the normal flow of blood through the heart.
There are many types of congenital heart defects. They range from simple defects with no symptoms to complex defects with severe, life-threatening symptoms.
Congenital heart defects are the most common type of birth defect. They affect 8 out of every 1,000 newborns. Each year, more than 35,000 babies in the United States are born with congenital heart defects.
Many of these defects are simple conditions. They need no treatment or are easily fixed. Some babies are born with complex congenital heart defects. These defects require special medical care soon after birth.
The diagnosis and treatment of complex heart defects has greatly improved over the past few decades. As a result, almost all children who have complex heart defects survive to adulthood and can live active, productive lives.
Most people who have complex heart defects continue to need special heart care throughout their lives. They may need to pay special attention to how their condition affects issues such as health insurance, employment, birth control and pregnancy, and other health issues.
In the United States, more than 1 million adults are living with congenital heart defects.
How the heart works
To understand congenital heart defects, it's helpful to know how a healthy heart works. Your child's heart is a muscle about the size of his or her fist. The heart works like a pump and beats 100,000 times a day.
The heart has two sides, separated by an inner wall called the septum. The right side of the heart pumps blood to the lungs to pick up oxygen. The left side of the heart receives the oxygen-rich blood from the lungs and pumps it to the body.
The heart has four chambers and four valves and is connected to various blood vessels. Veins are blood vessels that carry blood from the body to the heart. Arteries are blood vessels that carry blood away from the heart to the body.
Picture of a healthy heart cross-section.
The illustration shows a cross-section of a healthy heart and its inside structures. The blue arrow shows the direction in which oxygen-poor blood flows from the body to the lungs. The red arrow shows the direction in which oxygen-rich blood flows from the lungs to the rest of the body.
The heart has four chambers or "rooms."
- The atria (AY-tree-uh) are the two upper chambers that collect blood as it flows into the heart.
- The ventricles (VEN-trih-kuhls) are the two lower chambers that pump blood out of the heart to the lungs or other parts of the body.
Four valves control the flow of blood from the atria to the ventricles and from the ventricles into the two large arteries connected to the heart.
- The tricuspid (tri-CUSS-pid) valve is in the right side of the heart, between the right atrium and the right ventricle.
- The pulmonary (PULL-mun-ary) valve is in the right side of the heart, between the right ventricle and the entrance to the pulmonary artery. This artery carries blood from the heart to the lungs.
- The mitral (MI-trul) valve is in the left side of the heart, between the left atrium and the left ventricle.
- The aortic (ay-OR-tik) valve is in the left side of the heart, between the left ventricle and the entrance to the aorta. This artery carries blood from the heart to the body.
Valves are like doors that open and close. They open to allow blood to flow through to the next chamber or to one of the arteries. Then they shut to keep blood from flowing backward.
When the heart's valves open and close, they make a "lub-DUB" sound that a doctor can hear using a stethoscope.
- The first sound -- the "lub" -- is made by the mitral and tricuspid valves closing at the beginning of systole (SIS-toe-lee). Systole is when the ventricles contract, or squeeze, and pump blood out of the heart.
- The second sound -- the "DUB" -- is made by the aortic and pulmonary valves closing at the beginning of diastole (di-AS-toe-lee). Diastole is when the ventricles relax and fill with blood pumped into them by the atria.
The arteries are major blood vessels connected to your heart.
- The pulmonary artery carries blood from the right side of the heart to the lungs to pick up a fresh supply of oxygen.
- The aorta is the main artery that carries oxygen-rich blood from the left side of the heart to the body.
- The coronary arteries are the other important arteries attached to the heart. They carry oxygen-rich blood from the aorta to the heart muscle, which must have its own blood supply to function.
The veins also are major blood vessels connected to your heart.
- The pulmonary veins carry oxygen-rich blood from the lungs to the left side of the heart so it can be pumped to the body.
- The superior and inferior vena cavae are large veins that carry oxygen-poor blood from the body back to the heart.
What are the types of congenital heart defects?
With congenital heart defects, some part of the heart doesn't form properly before birth. This changes the normal flow of blood through the heart.
There are many types of congenital heart defects. Some are simple, such as a hole in the septum. The hole allows blood from the left and right sides of the heart to mix. Another example of a simple defect is a narrowed valve that blocks blood flow to the lungs or other parts of the body.
Other heart defects are more complex. They include combinations of simple defects, problems with the location of blood vessels leading to and from the heart, and more serious problems with how the heart develops.
Examples of Simple Congenital Heart Defects Holes in the Heart (Septal Defects)
The septum is the wall that separates the chambers on left and right sides of the heart. The wall prevents blood from mixing between the two sides of the heart. Some babies are born with holes in the septum. These holes allow blood to mix between the two sides of the heart.
Atrial septal defect (ASD). An ASD is a hole in the part of the septum that separates the atria—the upper chambers of the heart. The hole allows oxygen-rich blood from the left atrium to flow into the right atrium, instead of flowing into the left ventricle as it should. Many children who have ASDs have few, if any, symptoms.
ASDs can be small, medium, or large. Small ASDs allow only a little blood to leak from one atrium to the other. They don't affect how the heart works and don't need any special treatment. Many small ASDs close on their own as the heart grows during childhood.
Medium and large ASDs allow more blood to leak from one atrium to the other. They're less likely to close on their own.
About half of all ASDs close on their own over time. Medium and large ASDs that need treatment can be repaired using a catheter procedure or open-heart surgery.
Ventricular septal defect (VSD). A VSD is a hole in the part of the septum that separates the ventricles—the lower chambers of the heart. The hole allows oxygen-rich blood to flow from the left ventricle into the right ventricle, instead of flowing into the aorta and out to the body as it should.
What are the symptoms for congenital heart defects?
Serious congenital heart defects usually become evident soon after birth or during the first few months of life. Signs and symptoms could include:
- Pale gray or blue skin color (cyanosis)
- Rapid breathing
- Swelling in the legs, abdomen or areas around the eyes
- Shortness of breath during feedings, leading to poor Weight gain
Less serious congenital heart defects may not be diagnosed until later in childhood, because your child may not have any noticeable signs of a problem. If signs and symptoms are evident in older children, they may include:
- Easily becoming short of breath during exercise or activity
- Easily tiring during exercise or activity
- Fainting during exercise or activity
- Swelling in the hands, ankles or feet
When to see a doctor
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.
What are the causes for congenital heart defects?
If your child has a congenital heart defect, you may think you did something wrong during your pregnancy to cause the problem. However, doctors often don't know why congenital heart defects occur.
Heredity may play a role in some heart defects. For example, a parent who has a congenital heart defect may be more likely than other people to have a child with the defect. Rarely, more than one child in a family is born with a heart defect.
Children who have genetic disorders, such as Down syndrome, often have congenital heart defects. In fact, 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 septal defects.
Researchers continue to search for the causes of congenital heart defects.
What are the signs and symptoms and signs of congenital heart defects?
Many congenital heart defects cause few or no signs and symptoms. A doctor may not even detect signs of a heart defect during a physical exam.
Some heart defects do cause signs and symptoms. They depend on the number, type, and severity of the defects. Severe defects can cause signs and symptoms, usually in newborns. These signs and symptoms may include:
- Rapid breathing
- Cyanosis (a bluish tint to the skin, lips, and fingernails)
- Fatigue (tiredness)
- Poor blood circulation
Congenital heart defects don't cause chest pain or other painful symptoms.
Heart defects can cause heart murmurs (extra or unusual sounds heard during a heartbeat). Doctors can hear heart murmurs using a stethoscope. However, not all murmurs are signs of congenital heart defects. Many healthy children have heart murmurs.
Normal growth and development depend on a normal workload for the heart and normal flow of oxygen-rich blood to all parts of the body. Babies who have congenital heart defects may have cyanosis and 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 short of breath during physical activity.
Many types of congenital heart defects cause the heart to work harder than it should. With severe defects, this can lead to heart failure. Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Symptoms of heart failure include:
- Shortness of breath or trouble breathing
- Fatigue with physical activity
- A buildup of blood and fluid in the lungs
- Swelling in the ankles, feet, legs, abdomen, and veins in the neck
What are the treatments for congenital heart defects?
Although many children who have congenital heart defects don't need treatment, some do. Doctors repair congenital heart defects with catheter procedures or surgery.
Sometimes doctors combine catheter and surgical procedures to repair complex heart defects, which may involve several kinds of defects.
The treatment your child receives depends on the type and severity of his or her heart defect. Other factors include your child's age, size, and general health.
Some children who have complex congenital heart defects may need several catheter or surgical procedures over a period of years, or they may need to take medicines for years.
Catheter procedures are much easier on patients than surgery. They involve only a needle puncture in the skin where the catheter (thin, flexible tube) is inserted into a vein or an artery.
Doctors don't have to surgically open the chest or operate directly on the heart to repair the defect(s). This means that recovery may be easier and quicker.
The use of catheter procedures has increased a lot in the past 20 years. They have become the preferred way to repair many simple heart defects, such as atrial septal defect (ASD) and pulmonary valve stenosis.
For ASD repair, the doctor inserts a catheter into a vein in the groin (upper thigh). He or she threads the tube to the heart's septum. A device made up of two small disks or an umbrella-like device is attached to the catheter.
When the catheter reaches the septum, the device is pushed out of the catheter. The device is placed so that it plugs the hole between the atria. It's secured in place and the catheter is withdrawn from the body.
Within 6 months, normal tissue grows in and over the device. The closure device does not need to be replaced as the child grows.
For pulmonary valve stenosis, the doctor inserts a catheter into a vein and threads it to the heart's pulmonary valve. A tiny balloon at the end of the catheter is quickly inflated to push apart the leaflets, or "doors," of the valve.
Then, the balloon is deflated and the catheter and ballon are withdrawn. This procedure can be used to repair any narrowed valve in the heart.
To help guide the catheter, doctors often use echocardiography (echo), transesophageal (tranz-ih-sof-uh-JEE-ul) echo (TEE), and coronary angiography (an-jee-OG-rah-fee).
TEE is a special type of echo that takes pictures of the heart through the esophagus. The esophagus is the passage leading from the mouth to the stomach. Doctors also use TEE to examine complex heart defects.
A child may need open-heart surgery if his or her heart defect can't be fixed using a catheter procedure. Sometimes one surgery can repair the defect completely. If that's not possible, the child may need more surgeries over months or years to fix the problem.
Cardiac surgeons may use open-heart surgery to:
- Close holes in the heart with stitches or a patch
- Repair or replace heart valves
- Widen arteries or openings to heart valves
- Repair complex defects, such as problems with the location of blood vessels near the heart or how they are formed
Rarely, babies are born with multiple defects that are too complex to repair. These babies may need heart transplants. In this procedure, the child's heart is replaced with a healthy heart from a deceased child. The heart has been donated by the deceased child's family.
What are the risk factors for congenital heart defects?
Most congenital heart defects result from problems early in your child's heart development, the cause of which is unknown. However, certain environmental and genetic risk factors may play a role. They include:
- Rubella (German measles). Having rubella during pregnancy can cause problems in your baby's heart development. Your doctor can test you for immunity to this viral disease before pregnancy and vaccinate you against it if you aren't immune.
- Diabetes. You can reduce the risk of congenital heart defects by carefully controlling your diabetes before attempting to conceive and during pregnancy. Gestational diabetes generally doesn't increase your baby's risk of developing a heart defect.
Medications. Certain medications taken during pregnancy may cause birth defects, including congenital heart defects. Give your doctor a complete list of medications you take before attempting to become pregnant.
Medications known to increase the risk of congenital heart defects include thalidomide (Thalomid), angiotensin-converting enzyme (ACE) inhibitors, statins, the acne medication isotretinoin (Absorica, Amnesteem, Claravis) and lithium.
- Drinking alcohol during pregnancy. Avoid alcohol during pregnancy because it increases the risk of congenital heart defects.
- Smoking. Smoking during pregnancy increases the likelihood of a congenital heart defect in the baby.
Heredity. Congenital heart defects sometimes run in families and may be associated with a genetic syndrome. Many children with Down syndrome — which is caused by an extra 21st chromosome (trisomy 21) — have heart defects. A missing piece (deletion) of genetic material on chromosome 22 also causes heart defects.
Genetic testing can detect such disorders during fetal development. If you already have a child with a congenital heart defect, a genetic counselor can estimate the odds that your next child will have one.