Congenital heart defects and critical CHDs

What are congenital heart defects?

Congenital means present at birth. Congenital heart defects (also called CHDs) are heart conditions that a baby is born with. These conditions can affect the heart’s shape or how it works or both. CHDs can be mild or serious.

CHDs are the most common types of birth defects. Birth defects are structural changes present at birth that can affect almost any part of the body. They may affect how the body looks, works or both. Birth defects can cause problems in overall health, how the body develops or how the body works.

Critical congenital heart defects (also called critical CHDs or critical congenital heart disease) are the most serious congenital heart defects. Babies with critical CHDs need surgery or other treatment within the first year of life. Without treatment, critical CHDs can cause serious health problems and death.

Nearly 1 in 100 babies (about 1 percent or 40,000 babies) is born with a heart defect in the United States each year. About 1 in 4 babies born with a heart defect (about 25 percent) has a critical CHD. Some heart defects don’t need treatment or can be treated easily. But others, like some critical CHDs, may need surgeries over several years.

How can heart defects affect your baby?

Heart defects can affect different parts of your baby’s heart, including:

• Heart chambers. The heart has four chambers. The two upper chambers (also called atria) receive blood. The two lower chambers (also called ventricles) pump blood out of the heart to other parts of the body.
• Septum. This is a wall that separates the right and left sides of the heart. There is a wall between the two atria, and a wall between the two ventricles.
• Heart valves. These valves open and close to control blood flow through the heart. They help blood move in the right direction as it’s pumped to other parts of the body.
• Arteries and veins near the heart. Arteries are blood vessels that carry blood away from the heart to the body. The aorta is the main artery that carries blood away from the heart to the rest of the body. Veins are blood vessels that carry blood from the body to the heart.

Heart defects can affect blood flow, causing your baby’s blood to:

• Slow down
• Go in the wrong direction or to the wrong place
• Be blocked
• Not have enough oxygen to carry throughout the body

Some of these blood flow problems can cause fluid buildup in the lungs (also called lung congestion or pulmonary edema). Fluid in the lungs can make it harder for your baby to breathe. Babies with serious heart defects may develop heart failure (also called congestive heart failure). This is when the heart can’t pump blood as well as it should.

What are examples of critical CHDs?

Critical CHDs include:               

Coarctation of the aorta (also called COA). In this condition, part of the aorta is too narrow. This can reduce or block the flow of blood to the body. The heart muscles need to work harder to get blood out of the heart. This extra stress on the heart can weaken the heart muscle and cause other heart problems. Babies with COA are treated with surgery or a procedure called balloon angioplasty. In this procedure, a provider uses a catheter (a thin, flexible tube) with a tiny balloon that he expands to stretch open the aorta. He may put in a stent, which is a small mesh-covered tube used to keep the blood vessel open. Many children with COA need to take medicine to lower their blood pressure. Blood pressure is the force of blood against the walls of the arteries.

Dextro-Transposition of the Great Arteries (also called d-TGA). Babies with this condition have the positions of two important arteries switched. This means the blood that’s pumped to the body may not have enough oxygen. Babies with d-TGA need heart surgery soon after birth to help get oxygen-rich blood from the heart to the rest of the body. They may need medicines to make their heart pump better, lower their blood pressure, help the body get rid of extra fluid or slow down the heart if it’s beating too fast. If the heart is beating too slowly, they may need a pacemaker. A pacemaker is a small device placed under the skin in the chest to help control the heartbeat.

Interrupted aortic arch (also called IAA). In this condition, a part of the aorta is missing. This means that the heart can’t send blood through the aorta to the rest of the body. Babies with IAA need surgery soon after birth to repair the aorta.

Pulmonary atresia (also called PA). In this condition, the heart’s pulmonary valve doesn’t form properly or at all. The pulmonary valve controls blood flow from the right ventricle of the heart to the lungs. If a baby has PA, blood can’t flow from the heart to the lungs to pick up oxygen for the body. Babies with PA usually need medicine to improve blood flow until they can be treated with cardiac catheterization or surgery. During cardiac catheterization, your baby’s provider moves a catheter into a blood vessel and guides it to his heart. Then he can use a tiny balloon to expand the valve. Or he may put in a stent to keep a blood vessel open. But most babies with PA need surgery soon after birth to widen or replace the pulmonary valve.  

Single ventricle defects. In this group of conditions, a baby’s heart has one ventricle that works well enough to pump blood instead of two ventricles. Single ventricle defects include:

• Ebstein anomaly. In this condition, the heart’s tricuspid valve (the valve between the two right chambers of the heart) doesn’t work properly. This means blood can leak back into the wrong part of the heart. Babies with this condition may need surgery to repair or replace the tricuspid valve. They also may need medicines to control their heart rate, improve blood flow or treat any signs of heart failure. 
• Hypoplastic left heart syndrome (also called HLHS). In this condition, the left side of the heart doesn’t form correctly, and the heart can’t pump blood to the body properly. A baby with HLHS needs several different types of surgery starting soon after birth to help increase blood flow to her body. Some babies also need medicines to make their heart muscle stronger, lower their blood pressure or help the body get rid of extra fluid. If the condition is very severe or if surgeries weaken the heart, the baby may need a heart transplant. A heart transplant is surgery in which a damaged heart is removed and replaced with a healthy heart from another person.
• Tricuspid atresia. In this condition, the heart’s tricuspid valve (the valve between the two right chambers of the heart) isn’t formed. This means that blood can’t flow correctly through the heart or to the rest of the body. Babies with tricuspid atresia may need one or more surgeries starting soon after birth to increase blood flow to the lungs and bypass (go around) the part of the heart that’s not working properly. Some babies need medicines to make the heart muscle stronger, lower their blood pressure, or help the body get rid of extra fluid.
• Double-outlet right ventricle (also called DORV). In this condition, the aorta connects to the heart’s right ventricle instead of the left ventricle. There’s also a hole between the two ventricles. This means that the blood being pumped to the body may not have enough oxygen. Babies with DORV need surgery to repair the heart.

Tetralogy of Fallot (also called TOF). Babies with this condition have a combination of four heart defects that limits oxygen in blood that’s pumped to the body. Babies with TOF need heart surgery soon after birth to improve blood flow to the lungs and the rest of the body.

Total anomalous pulmonary venous return (also called TAPVR). In this condition, the veins that take blood from the lungs to the heart don’t connect to the heart the right way, so the body doesn’t get enough oxygen. Babies with this condition need surgery so that blood can flow better through the heart.

Truncus arteriosus (also called common truncus). Babies with this condition have only one artery that leaves the heart instead of two arteries. They also have only one valve that controls the blood that leaves the heart instead of two valves. This means that blood with oxygen mixes with blood that doesn’t have oxygen. So too much blood goes to the lungs, and the heart has to work harder to pump blood to the rest of the body. Babies with this condition need surgery to repair the heart and blood vessels. Some babies may need medicines to make the heart muscle stronger, lower their blood pressure or help the body get rid of extra fluid.

As they grow older, most babies with critical CHDs need regular checkups with a pediatric cardiologist to check the heart and look for any other health problems.

What are common congenital heart defects and how are they treated?

Common CHDs include:

Patent ductus arteriosus (also called PDA). This condition happens in the connection (called the ductus arteriosus) between two major blood vessels leading from the heart: the pulmonary artery and the aorta. The ductus arteriosus is open when a baby is in the womb. If it doesn’t close properly after birth, blood that doesn’t have enough oxygen can flow in the wrong direction. This can weaken the heart muscle and lead to heart failure. Sometimes a PDA may close on its own. But some babies need medicine, procedures with catheters or heart surgery.

Septal defects. These conditions leave a hole in the septum. This can cause blood to go in the wrong direction or to the wrong place, or it can cause extra blood to be pumped to the lungs. Types of septal defects include:

• Atrial septal defect (also called ASD). This is when the hole is in the wall that separates the right and left atria.
• Ventricular septal defect (also called VSD). This is when the hole is in the wall that separates the right and left ventricles. VSDs are the most common type of heart defect.
• Atrioventricular septal defect (AVSD). This is when there are holes between the chambers of the right and left side of the heart, and the valves between these chambers may not form correctly.

Some small septal defects close on their own. Heart surgery or procedures with catheters can fix larger septal defects. Babies with AVSD usually need heart surgery.

What causes congenital heart defects?

Heart defects can begin to develop in the first 6 weeks of pregnancy when the heart is forming, often before you know you’re pregnant. We’re not sure what causes most congenital heart defects, but these things may play a role:

Changes in genes or chromosomes

Some babies have heart defects because of changes in their chromosomes or genes. Chromosomes are the structures that hold genes. Genes are part of your body’s cells that store instructions for the way your body grows and works. Genes are passed from parents to children. Certain gene changes (also called mutations) are linked to heart defects. At least 15 in 100 (15 percent) of CHDs are linked to genetic or chromosomal conditions. For example, about half of babies with Down syndrome have heart defects.

If you, your partner or one of your other children has a congenital heart defect, your next baby may be more likely to have one, too. So you may want to meet with a genetic counselor. This is a person who is trained to help you understand genes, birth defects and other medical conditions that run in families, and how they can affect your health and your baby’s health.

Health conditions in mom

Having one of these conditions may increase your risk of having a baby with a CHD:

• Lupus (also called systemic lupus erythematosus or SLE). Lupus is an autoimmune disease. This is a health condition that happen when antibodies (cells in the body that fight off infections) attack healthy tissue by mistake. Lupus can damage the joints, skin, kidneys, heart, lungs and other body parts.
• Maternal phenylketonuria (also called PKU). PKU is a condition in which your body can’t break down an amino acid called phenylalanine. Amnio acids help build protein in your body. Without treatment, phenylalanine builds up in the blood and causes health problems. Most pregnant women with PKU can have healthy babies if they follow a special mean plan that’s low in phenylalanine.
• Obesity (being very overweight). If you’re obese, you have an excess amount of body fat, and your body mass index (BMI) is 30 or higher. To find out your BMI, go to www.cdc.gov/bmi.
• Preexisting diabetes (also called type 1 or type 2 diabetes). This is a medical condition in which your body has too much sugar (called glucose) in your blood. Preexisting means you had diabetes before you got pregnant. Diabetes can damage organs in your body, including blood vessels, nerves, eyes and kidneys.
• Rubella (also called German measles). This is an infection that causes mild flu-like symptoms and rash on the skin. Having rubella during pregnancy may increase your baby’s risk for a CHD.

Medicines you take

Taking certain medicines may increase your baby’s risk of having a CHD. Tell your provider about any medicine you take before you try to get pregnant. This includes prescription medicines, over-the counter medicine, herbal products and supplements.

If the medicine you take may be harmful to your baby, you may be able to change to one that’s safer. But some medicines may be critical to your own health, even if they may affect your baby. You and your provider can weigh the benefits and risks of medicine you take to give you the healthiest possible pregnancy. Don’t start or stop taking any prescription medicine before, during or after pregnancy without talking to your health care provider first. Starting, stopping or changing medicines may cause serious health problems for you or your baby.

These are examples of medicines that may increase your baby’s risk of having a CHD:

• ACE inhibitors. These medicines are used to treat high blood pressure and other conditions. High blood pressure is when the force of blood against the walls of the blood vessels is too high. It can stress your heart and cause problems during pregnancy.
• Isotretinoin. This medicine is used to treat acne.
• Lithium. This medicine is used to treat depression. Depression (also called depressive disorder, major depression and clinical depression) is a medical condition that causes feelings of sadness and a loss of interest in things you like to do. It can affect how you feel, think and act and can interfere with your daily life. It needs treatment to get better.
• Statins. These medicines are used to treat high cholesterol. Cholesterol is a substance in your blood. Too much cholesterol can increase your risk of heart disease.
• Thalidomide. This medicine is used to treat certain skin conditions, infections, certain types of cancer and complications from HIV (stands for human immunodeficiency virus). HIV attacks the body’s immune system and is the virus that causes AIDS. In a healthy person, the immune system protects the body from infections, cancers and some diseases.

Conditions in your everyday life (lifestyle and environment)

Some things in your life and environment (where and how you live) may increase your chances of having a baby with a CHD. These include:

• Drinking alcohol during pregnancy. If you’re pregnant, trying to get pregnant or think you may be pregnant, don’t drink alcohol.
• Smoking before or during pregnancy. Women who smoke anytime during the month before pregnancy or during the first 3 months of pregnancy are more likely to have a baby with a CHD than women who don’t smoke.

If you smoke or drink alcohol, ask your health care provider about getting help to quit.

How do you know if your baby has a congenital heart defect?

If your health care provider doesn’t find a severe congenital heart defect in your baby during pregnancy, it’s usually diagnosed soon after birth or during the first few months of life. Less severe heart defects may not be found until children are older.

During pregnancy

Your provider may use a test called fetal echocardiogram (also called fetal echo) to check your baby’s heart. This test uses ultrasound to make a picture of your baby’s heart while still in the uterus (womb). You can have this test at about 18 to 24 weeks of pregnancy.

You may need a fetal echocardiogram if:

• Your provider finds a possible problem, like an abnormal heart rhythm in your baby, during an ultrasound.
• Your baby has a genetic or chromosomal condition, like Down syndrome, that may be linked to CHDs.
• You have a family history of heart problems. This means that you, your partner or someone in your families has heart problems.
• You have a health condition, like diabetes, that may play a role in CHDs.
• You’re taking a medicine that can increase the risk of your baby having a CHD.

After birth

Your baby is tested for critical CHDs as part of newborn screening before she leaves the hospital after birth. Newborn screening checks for serious but rare and mostly treatable conditions. It includes blood, hearing and heart screening. All states require newborn screening, and all states except California require screening for critical CHDs. California requires that providers offer screening for critical CHDs.

Babies are screened for critical CHDs with a simple test called pulse oximetry (also called pulse ox). This test checks the amount of oxygen in your baby’s blood. Low levels of oxygen can be a sign of a heart defect. Pulse oximetry uses a pulse oximeter machine with sensors that are placed on your baby’s skin. The test is painless and only takes a few minutes. Pulse oximetry can find many but not all critical CHDs. Your baby’s provider also may find a heart defect by doing a physical exam.

If tests find that your baby has a critical CHD, she can get early care and treatment to prevent more serious health problems. Your baby’s provider can refer your baby to a pediatric cardiologist for treatment. This is a doctor who treats babies and children with heart conditions.

What are signs and symptoms of congenital heart defects?

Signs of a condition are things someone else can see or know about you, like you have a rash or you’re coughing. Some CHDs have no signs, so you may not know that your baby has a CHD until he’s older.

Signs of heart defects include:

• A heart murmur. This is a blowing, whooshing or rasping sound heard during a heartbeat. It’s caused by rough blood flow through the heart valves or near the heart. Your baby’s provider may hear a murmur when she checks your baby’s heartbeat using a stethoscope.
• A pounding heart
• A weak pulse
• Gray or blue color of the skin, lips or fingernails
• Sleepiness while feeding or being very sleepy at other times
• Swollen belly or legs or puffiness around the eyes
• Trouble breathing or fast breathing. Breathing problems while feeding can lead to slow weight gain.

If your baby has any of these signs, call his provider right away. Your baby’s provider may use these tests to check for heart defects:

• Physical exam. Your baby’s provider listens to your baby’s heart and lungs with a stethoscope and looks for other signs of a heart defect.
• Echocardiogram (also called an echo or cardiac ultrasound). This is an ultrasound of the heart. Your baby’s provider can see the heart beating and check the heart’s valves and other parts.
• Electrocardiogram (also called EKG or ECG). This test records the heart’s electrical activity. It shows how fast the heart is beating and if its rhythm is steady or not. It also shows the size and position of the heart’s chambers.
• Chest X-ray. This test makes pictures of your baby’s chest and organs, like the heart and lungs. It can show if the heart is enlarged. It also can show if the lungs have extra blood or other fluid in them. An enlarged heart or extra fluid in the lungs can be signs of heart failure.
• Pulse oximetry
• Cardiac catheterization

Last reviewed: June, 2019