Congenital Heart Defects

Heart defects are among the most common birth defects (Read about "Birth Defects") in the United States, according to the March of Dimes (MOD), affecting nearly one in every hundred births. Congenital (meaning present at birth) heart defects can affect any part of the heart. They can range from problems that pose no health risks to problems that are life threatening. Sometimes congenital heart defects produce early symptoms, such as gray or bluish skin tone. Sometimes symptoms are delayed for years. And sometimes congenital heart defects produce no symptoms at all.

One thing congenital heart defects have in common is that in most cases, we don't exactly know why they develop. Potential risk factors include genetics (Read about "Genetics"), medications taken during pregnancy, and viruses affecting the mother during pregnancy. (Read about "Healthy Pregnancy") Women with chronic conditions such as diabetes are also at higher risk, and need to monitor their condition closely during pregnancy. (Read about "Diabetes") Children with other issues, such as Down syndrome, are also at increased risk. (Read about "Down Syndrome")

Some of the more common congenital birth defects, according to MOD and the American Heart Association (AHA) include:

• Patent ductus arteriosus - The ductus arteriosus is a fetal passageway that lets blood flow bypass the lungs prior to birth. It is supposed to close soon after birth, so blood can flow normally. When it does not, the condition is called patent (or "open") ductus arteriosus. This problem happens more with premature babies. (Read about "Preterm Labor") MOD says treatment can involve medication and/or surgery.
• Patent foramen ovale - The foramen ovale is another way the blood bypasses the lungs before we are born. The flap-like opening between the two upper chambers of our heart is supposed to close when we are born and seal tight in the first few days and weeks of life. When it doesn't close correctly, it is called a patent (or "open") foramen ovale. Most people never know they have it. It has been implicated as a possible risk factor for stroke. (Read about "Patent Foramen Ovale" "Stroke") It should not be confused with an atrial septal defect, which is much more serious.
• Atrial septal defect - The atrial septum is the wall that divides the left and right atria (the upper chambers of the heart). A hole or opening in this septum means blood can't flow through the heart, as it should. Smaller holes may close on their own and not require surgery. Surgery may be needed for larger holes. Large atrial septal defects can damage the heart and lungs over time. An adult who has had an undetected atrial septal defect for decades may develop other heart issues.
• Ventricular septal defect - The ventricular septum is the wall that divides the left and right ventricles (the lower chambers of the heart). A hole in this septum means blood can't flow, as it should. Smaller holes may close on their own and not require surgery. Surgery may be needed for larger holes.
• Coarctation of the aorta - The aorta is the artery through which blood flows out from the heart to the rest of the body. A coarctation is a narrowing of the aorta, which means blood can't flow normally. This defect may not be diagnosed until later in life. It can be treated with surgery or dilation.
• Tetralogy of Fallot - This is actually a combination of four defects. It results in cyanosis or blueness, which may appear soon after birth, in infancy or later in childhood, as well as other symptoms such as rapid breathing, and even loss of consciousness, which can come on suddenly, because not enough blood is flowing to the lungs. Surgery is often required to repair the defects. (Read about "Respiratory System")
• Transposition of the great arteries - In this condition, the two major arteries leaving the heart (the pulmonary artery and the aorta) are switched. When this happens, the body can't get the oxygenated blood it needs to survive, and corrective surgery is essential.
• Valve disorders - When a valve is narrowed or blocked (stenosis), blood can't flow smoothly. If the valve doesn't close correctly, it leaks (regurgitation). Defective valves can be repaired or replaced. (Read about "The Heart and Its Valves") Examples of congenital valve disorders include:
  • Aortic stenosis - The aortic valve is between the left ventricle and the aorta. When there is a narrowing or stenosis, the heart can't pump blood properly. AHA says most children with aortic stenosis have no symptoms. When symptoms are present, they can include chest pain and dizziness. Treatment options include surgery or a procedure called balloon valvuloplasty.
  • Pulmonary stenosis - The pulmonary valve is between the right ventricle and the pulmonary artery. A narrowing that interferes with the flow of blood is called stenosis. In severe cases, the skin may turn slightly bluish, according to AHA. Treatment options include surgery or a procedure called balloon valvuloplasty.

Other, less common, types of congenital heart defects include:

• Hypoplastic left heart syndrome - in which the left side of the heart is underdeveloped
• Tricuspid atresia - in which there's no tricuspid valve so blood can't flow as it should from the right atrium to the right ventricle
• Pulmonary atresia - in which there's no pulmonary valve, so blood can't flow as it should from the right ventricle and on to the lungs
• Atrioventricular canal defect - in which a large hole exists in the center of the heart
• Subaortic stenosis - in which there is constriction just below the aortic valve
• Ebstein's anomaly - which is a displacement of the tricuspid valve

Not all congenital heart defects require treatment. But some are serious and do need to be treated. The specific treatment depends on the type of defect. Potential options include:

• Medications - some congenital heart defects can be successfully treated with medications to make the heart work better.
• Catheterization - this involves the insertion of a thin tube into a vein, which is then threaded to the heart, where repairs can be made using small tools, which are themselves threaded through the catheter.
• Surgery - some defects, which are very serious, can't be repaired with catheterization and require open heart surgery.
• Heart transplant - severe defects that cannot be corrected with surgery may require a heart transplant. (Read about "Transplants")

MOD says that half the children who require surgical repair of a heart defect commonly undergo surgery before the age of two. MOD says early surgery can help the baby avoid additional complications and get back to normal sooner. Some conditions, however, require a temporary repair, with more major surgical correction delayed until the child is older. For some patients, minimally-invasive robotic-assisted surgery is an option. (Read about "Robotic Surgery")

It's important for parents to be aware of the fact that treatment for certain congenital heart defects puts the child at greater risk for getting an infection of the valves called endocarditis. (Read about endocarditis in "The Heart and Its Valves") Parents should discuss with their doctor whether their child needs to take antibiotics (Read about "Antibiotics") before certain dental and surgical procedures.

Some congenital heart defects can be identified before birth by ultrasound. (Read about "Ultrasound Imaging") Since the exact cause of such birth defects is unknown, there is no known way to prevent them. MOD says, however, that a woman can reduce the risk by:

• being tested for rubella
• avoiding alcohol and drug abuse during pregnancy (Read about "Alcoholism" "Addiction")
• discussing monitoring chronic conditions with her doctor

Research continues to learn more about congenital heart defects and how to treat them. Meanwhile, the International Society for Adult Congenital Cardiac Disease (ISACCD) says those diagnosed with a congenital heart defect need to be aware of their continuing risks as they age. Depending on their specific defect, they may be at greater risk for additional disorders including arrhythmia, congestive heart failure, pulmonary hypertension or endocarditis. (Read about "Arrhythmia" "Congestive Heart Failure" "Pulmonary Hypertension" and find endocarditis in "The Heart and Its Valves") They may need additional surgery later on. Women will need to discuss the risks of pregnancy with their doctors. ISACCD also says parents with congenital heart defects are more likely to have affected children than are parents with normal hearts. Again, you should discuss all concerns with your doctor.

Related Information:

    The Heart & Cardiovascular System

    Heart Terms Glossary