What is congenital heart disease? What causes congenital heart defects? What are the symptoms of congenital defects? How are congenital defects diagnosed? How are congenital heart defects treated? What are the types of congenital defects? ***** Obstructive   Septal   Cyanotic   Hypoplastic left heart Other Sites

A congenital heart defect occurs when the heart or blood vessels near the heart don't develop normally before birth.Terms used to describe this condtions include congenital heart defect, congenital heart disease and congenital cardiovascular disease. The word "defect" is more accurate than "disease."

Aquired defects develop after birth and may be caused by injury, infection or aging. Links to pages discussing aquired heart disease can be found on the:

"Heart Information Center"

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Congenital cardiovascular defects are present in about one percent of births and are the most common congenital malformations in newborns. The cause is not known in most cases. Certain viral infections may cause serious problems. German measles (also called rubella) and other viral diseases also may produce congenital defects by interfering with the development of the baby's heart during pregnancy.

Heredity is involved in some cases ofcongenital cardiovascular disease. It is uncommon for more than one child in a family to have a congenital cardiovascular defect. Certain conditions, such as Down's syndrome, can involve the heart along with other organs. Certain prescription drugs and over-the-counter medicines, as well as alcohol and "street" drugs, can increase the risk of having a baby with a heart defect.

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Symptoms of congenital heart disease depend on the type of defect as well as the severity of the defect. For example, severe aortic stenosis may present with severe symptoms in early infancy while mild stenosis may have few or no symptoms until later in life. The more blood flow and oxygen delivery to vital organs is impaired the earlier symptoms will appear.

In infants symptoms may include failure to grow and gain weight. These infants usually tire easily when feeding and are not as active as healthy infants. Symptoms in children and adults may include chest pain, easy fatigabiltiy, dizziness with fainting episoides- especially with physical exertion. Symptoms will be discussed for each specific condition.

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Persons with severe symptoms of congenital heart disease often seek medical help. Some defects cause heart murmers (abnormal heart sounds) that can be heard when a doctor listens to the heart with a stethoscope. In patients with mild or no symptoms a heart murmer may be "accidently" discovered by a doctor during a routine exam. Not all heart defects cause murmers and not all murmers are caused by congenital defects. If a murmer is heard and there are symptoms present additional tests may be ordered.

Such tests include:

• Echocardiogram in which high frequency sound waves are bounced off the heart to produce a "picture" of the internal structures of the heart.
• Heart catheterization in which dye is injected into blood vessels near the heart and a series of pictures is rapidly taken to produce a picture of the heart in motion.
• a thin plastic catheter may be threaded into the heart to measure the pressures in the different chambers of the heart with either of the above studies.

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There is no single method to treat congenital heart defects. Some defects may not require treatment, some may be managed with medication while others may require surgical repair. This is a very specialized area of medical treatment. A general overview will be discussed for each specific condition.

Most patients with congenital heart disease will require a brief treatment with antibiotics before most dental or surgical procedures to reduce the risk of bacteria getting into their blood stream and causing infection of the heart valves. Infection of a heart valve(s) with bacteria or fungi is called endocarditis.

The heart valves of persons with congenital heart defects are much more susceptible to endocarditis than those of people without congenital heart disease. [see Valvular Heart Disease for more information about endocarditis]

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Most heart defects either 1) block blood flow in the heart or vessels near it or 2) cause blood to flow through the heart in an abnormal pattern. Rarely defects occur in which only one ventricle (single ventricle) is present, or both the pulmonary artery and aorta arise from the same ventricle (double outlet ventricle). A third rare defect occurs when the right or left side of the heart is incompletely formed — hypoplastic heart.

see animated tutorial
"How the Heart Pumps Blood"

An obstruction is a narrowing that partly or completely blocks the flow of blood. Obstructions are called stenoses and can occur in heart valves, arteries or veins.

Obstruction defects include:

1. Pulmonary stenosis
2. Aortic stenosis
3. Coarctation of the aorta
4. Bicuspid aortic valve
5. Subaortic stenosis
6. Ebstein's anomaly

The three most common forms of obstructed blood flow are pulmonary stenosis, aortic stenosis and coarctation of the aorta. Related but less common forms include bicuspid aortic valve, subaortic stenosis and Ebstein's anomaly.

• Pulmonary stenosis (P.S.) The pulmonary or pulmonic valve is between the right ventricle and the pulmonary artery. It opens to allow blood to flow from the right ventricle to the lungs. A defective pulmonary valve that does not open properly is called stenotic. That means the right ventricle must pump harder than normal to overcome the obstruction.

  If the stenosis is severe, especially in babies, cyanosis (blueness) may occur. Older children usually have no symptoms. Treatment is needed when the pressure in the right ventricle is higher than normal. In most children the obstruction can be relieved by a procedure called balloon valvuloplasty. In other patients, open heart surgery may be needed. During surgery, the valve can usually be opened satisfactorily. The outlook after balloon valvuloplasty or surgery is favorable, but follow-up is required to determine if heart function returns to normal

• Aortic stenosis (A.S.) - The aortic valve, between the left ventricle and the aorta , is narrowed. This makes it hard for the heart to pump blood to the body. Aortic stenosis occurs when the aortic valve didn't form properly. A normal valve has three leaflets or cusps, but a stenotic valve may have only one cusp (unicuspid) or two cusps (bicuspid), which are thick and stiff. (See bicuspid aortic valve below.)

  Sometimes stenosis is severe and symptoms occur in infancy. Otherwise, most children with aortic stenosis have no symptoms. In some children, chest pain, unusual tiring, dizziness or fainting may occur. The need for surgery depends on how bad the stenosis is. In children, a surgeon may be able to enlarge the valve opening. Although surgery may improve the stenosis, the valve remains deformed. Eventually, the valve may need to be replaced with an artificial one.

  A procedure called balloon valvuloplasty has been used in some children with aortic stenosis. The long-term results of this procedure are still being studied. Children with aortic stenosis need lifelong medical follow-up. Even mild stenosis may worsen over time, and surgical relief of a blockage is sometimes incomplete. Check with your pediatric cardiologist about limiting some kinds of exercise.

• Coarctation of the aorta - The aorta is pinched or constricted. This decreases blood flow to the lower part of the body and increases blood pressure above the constriction. Usually there are no symptoms at birth, but they can develop as early as the first week after birth. A baby may develop congestive heart failure or high blood pressure that requires early surgery. Otherwise, surgery usually can be delayed. A child with a severe coarctation should have surgery in early childhood. This prevents problems such as developing high blood pressure as an adult.

  The outlook after surgery is favorable, but long-term follow-up is required. Rarely, coarctation of the aorta may recur. Some of these cases can be treated by balloon angioplasty . The long-term results of this procedure are still being studied. Also, blood pressure may stay high even when the aorta's narrowing has been repaired.

• Bicuspid aortic valve - The normal aortic valve has three flaps, or cusps, that open and close. A bicuspid valve has only two flaps, rather than three. There may be no symptoms in childhood, but by adulthood (often middle age or older) the valve can become stenotic (narrowed), making it harder for blood to pass through it, or regurgitant (allowing blood to leak backward through it). Treatment depends on how well the valve functions.
  
  
• Subaortic stenosis - Stenosis means constriction or narrowing. Subaortic means below the aorta . Subaortic stenosis refers to a narrowing of the left ventricle just below the aortic valve, which blood passes through to go into the aorta. This stenosis limits the flow of blood out of the left ventricle. This condition may be congenital or may be due to a particular form of cardiomyopathy known as "idiopathic hypertrophic subaortic stenosis" (I.H.S.S.). Treatment depends on the cause and the severity of the narrowing. It can include drugs or surgery.
  
  
• Ebstein's anomaly is a congenital downward displacement of the tricuspid valve (located between the upper and lower chambers on the right side of the heart) into the right bottom chamber of the heart (or right ventricle). It is usually associated with an atrial septal defect (see below).

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Some congenital cardiovascular defects allow blood to flow between the right and left chambers of the heart. This happens when a baby is born with an opening between the wall (septum) that separates the right and left sides of the heart. This defect is sometimes called "a hole in the heart."

Septal defects include:

1. Atrial septal defect (ASD)
2. Ventricular septal defect (VSD)
3. Eisenmenger's complex
4. Atrioventricular (A-V) canal defect (also called endocardial cushion defect )

The two most common types of this defect are atrial septal defect and ventricular septal defect. Two variations are Eisenmenger's complex and atrioventricular canal defect.

• Atrial septal defect (A.S.D.) - An opening exists between the two upper chambers of the heart. This allows some blood from the left atrium (blood that's already been to the lungs) to return via the hole to the right atrium instead of flowing through the left ventricle , out the aorta and to the body. Many children with ASD have few, if any, symptoms. Closing the atrial defect by open heart surgery in childhood can prevent serious problems later in life.
  
  
• Ventricular septal defect (V.S.D.) - An opening exists between the two lower chambers of the heart. Some blood that has returned from the lungs and has been pumped into the left ventricle flows to the right ventricle through the hole instead of being pumped into the aorta. The heart, which has to pump extra blood, is over-worked and may enlarge.

  If the opening is small, it doesn't strain the heart. In that case, the only abnormal finding is a loud murmur. But if the opening is large, open heart surgery is recommended to close the hole and prevent serious problems. Some babies with a large ventricular septal defect don't grow normally and may become undernourished. Babies with VSD may develop severe symptoms or high blood pressure in their lungs. Repairing a ventricular septal defect with surgery usually restores the blood circulation to normal. The long-term outlook is good, but long-term follow-up is required.

• Eisenmenger's complex is a ventricular septal defect coupled with pulmonary high blood pressure, the passage of blood from the right side of the heart to the left (right to left shunt), an enlarged right ventricle and a latent or clearly visible bluish discoloration of the skin called cyanosis . It may also include a malpositioned aorta that receives ejected blood from both the right and left ventricles (an overriding aorta

• Atrioventricular (A-V) canal defect (also called endocardial cushion defect or atrioventricular septal defect) - A large hole in the center of the heart exists where the wall between the upper chambers joins the wall between the lower chambers. Also, the tricuspid and mitral valves that normally separate the heart's upper and lower chambers aren't formed as individual valves. Instead, a single large valve forms that crosses the defect.

  The large opening in the center of the heart lets oxygen-rich (red) blood from the heart's left side - blood that's just gone through the lungs - pass into the heart's right side. There, the oxygen-rich blood, along with venous (bluish) blood from the body, is sent back to the lungs. The heart must pump an extra amount of blood and may enlarge. Most babies with an atrioventricular canal don't grow normally and may become undernourished. Because of the large amount of blood flowing to the lungs, high blood pressure may occur there and damage the blood vessels.

  In some babies the common valve between the upper and lower chambers doesn't close properly. This lets blood leak backward from the heart's lower chambers to the upper ones. This leak, called regurgitation or insufficiency, can occur on the right side, left side, or both sides of the heart. With a valve leak, the heart pumps an extra amount of blood, becomes overworked and enlarges.

  In babies with severe symptoms or high blood pressure in the lungs, surgery must usually be done in infancy. The surgeon closes the large hole with one or two patches and divides the single valve between the heart's upper and lower chambers to make two separate valves. Surgical repair of an atrioventricular canal usually restores the blood circulation to normal. However, the reconstructed valve may not work normally.

  Rarely, the defect may be too complex to repair in infancy. In this case, the surgeon may do a procedure called pulmonary artery banding to reduce the blood flow and high pressure in the lungs. When a child is older, the band is removed and corrective surgery is done. More medical or surgical treatment is sometimes needed.

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Another classification of heart defects is congenital cyanotic heart defects. In these defects, blood pumped to the body contains less-than-normal amounts of oxygen. This results in a condition called cyanosis , a blue discoloration of the skin. The term "blue babies" is often applied to infants with cyanosis.

Examples of cyanotic defects are:

1. Patent ductus arteriosus
2. Tetralogy of Fallot,
3. Transposition of the great arteries,
4. Tricuspid atresia,
5. Pulmonary atresia,
6. Truncus arteriosus
7. Total anomalous pulmonary venous connection.

• Patent ductus arteriosus (P.D.A.)

  This defect allows blood to mix between the pulmonary artery and the aorta . Before birth there's an open passageway (the ductus arteriosus) between these two blood vessels. Normally this closes within a few hours of birth. When this doesn't happen, however, some blood that should flow through the aorta and on to nourish the body returns to the lungs. A ductus that doesn't close is quite common in premature infants but rather rare in full-term babies.

  If the ductus arteriosus is large, a child may tire quickly, grow slowly, catch pneumonia easily and breathe rapidly. In some children symptoms may not occur until after the first weeks or months of life. If the ductus arteriosus is small, the child seems well. If surgery is needed, the surgeon can close the ductus arteriosus by tying it, without opening the heart. If there's no other defect, this restores the circulation to normal.

• Tetralogy of Fallot has four components. The two major ones are: 1) a large hole, or ventricular septal defect, that allows blood to pass from the right ventricle to the left ventricle without going through the lungs, and 2) a narrowing (stenosis) at or just beneath the pulmonary valve. This narrowing partially blocks the flow of blood from the right side of the heart to the lungs. The other two components are: 3) the right ventricle is more muscular than normal, and 4) the aorta lies directly over the ventricular septal defect.

  This results in cyanosis (blueness), which may appear soon after birth, in infancy or later in childhood. These "blue babies" may have sudden episodes of severe cyanosis with rapid breathing. They may even become unconscious. During exercise, older children may become short of breath and faint. These symptoms occur because not enough blood flows to the lungs to supply the child's body with oxygen.

  Some infants with severe tetralogy of Fallot may need an operation to give temporary relief by increasing blood flow to the lungs with a shunt. This is done by making a connection between the aorta and the pulmonary artery. Then some blood from the aorta flows into the lungs to get more oxygen. This reduces the cyanosis and allows the child to grow and develop until the problem can be fixed when the child is older.

  Most children with tetralogy of Fallot have open-heart surgery before school age. The operation involves closing the ventricular septal defect and removing the obstructing muscle. After surgery the long-term outlook varies, depending largely on how severe the defects were before surgery. Lifelong medical follow-up is needed.

• Transposition of the great arteries - The positions of the pulmonary artery and the aorta are reversed. The aorta is connected to the right ventricle , so most of the blood returning to the heart from the body is pumped back out without first going to the lungs. The pulmonary artery is connected to the left ventricle, so that most of the blood returning from the lungs goes back to the lungs again.

  Infants born with transposition survive only if they have one or more connections that let oxygen-rich blood reach the body. One such connection may be a hole between the two atria , called atrial septal defect, or between the two ventricles , called ventricular septal defect. Another may be a vessel connecting the pulmonary artery with the aorta, called patent ductus arteriosus . Most babies with transposition of the great arteries are extremely blue (cyanotic) soon after birth because these connections are inadequate.

  To improve the body's oxygen supply, a special procedure called balloon atrial septostomy is used. Two general types of surgery may be used to help fix the transposition. One is a venous switch or intra-atrial baffle procedure that creates a tunnel inside the atria. Another is an arterial switch. After surgery, the long-term outlook is varies quite a bit. It depends largely on how severe the defects were before surgery. Lifelong follow-up is needed

• Tricuspid atresia - In this condition, there's no tricuspid valve. That means no blood can flow from the right atrium to the right ventricle . As a result, the right ventricle is small and not fully developed. The child's survival depends on there being an opening in the wall between the atria called an atrial septal defect and usually an opening in the wall between the two ventricles called a ventricular septal defect. Because the circulation is abnormal, the blood cannot get enough oxygen, and the child looks blue (cyanotic) .

  Often in these cases a surgical shunting procedure is needed to increase blood flow to the lungs. This reduces the cyanosis. Some children with tricuspid atresia have too much blood flowing to the lungs. They may need a procedure (pulmonary artery banding) to reduce blood flow to the lungs. Other children with tricuspid atresia may have a more functional repair (Fontan procedure). Children with tricuspid atresia require lifelong follow-up by a pediatric cardiologist.

• Pulmonary atresia - No pulmonary valve exists, so blood can't flow from the right ventricle into the pulmonary artery and on to the lungs. The right ventricle acts as a blind pouch that may stay small and not well developed. The tricuspid valve is often poorly developed, too.

  An opening in the atrial septum lets blood exit the right atrium , so venous (bluish) blood mixes with the oxygen-rich (red) blood in the left atrium. The left ventricle pumps this mixture of oxygen-poor blood into the aorta and out to the body. The baby appears blue (cyanotic) because there's less oxygen in the blood circulating through the arteries. The only source of lung blood flow is the patent ductus arteriosus (PDA), an open passageway between the pulmonary artery and the aorta. If the PDA narrows or closes, the lung blood flow is reduced to critically low levels. This can cause very severe cyanosis.

  Early treatment often includes using a drug to keep the PDA from closing. A surgeon can create a shunt between the aorta and the pulmonary artery to help increase blood flow to the lungs. A more complete repair depends on the size of the pulmonary artery and right ventricle. If the pulmonary artery and right ventricle are very small, it may not be possible to correct the defect with surgery. In cases where the pulmonary artery and right ventricle are more normal size, open-heart surgery may produce a good improvement in how the heart works.

  If the right ventricle stays too small to be a good pumping chamber, then the surgeon can connect the right atrium directly to the pulmonary artery. The atrial defect also can be closed to relieve the cyanosis. This is called a Fontan procedure. Children with tricuspid atresia require lifelong follow-up by a pediatric cardiologist.

• Truncus arteriosus - This is a complex malformation where only one artery arises from the heart and forms the aorta and pulmonary artery . Surgery for this condition usually is required early in life. It includes closing a large ventricular septal defect within the heart, detaching the pulmonary arteries from the large common artery, and connecting the pulmonary arteries to the right ventricle with a tube graft. Children with truncus arteriosus need lifelong follow-up to see how well the heart is working.

• Total anomalous pulmonary venous (P-V) connection - The pulmonary veins that bring oxygen-rich (red) blood from the lungs back to the heart aren't connected to the left atrium . Instead, the pulmonary veins drain through abnormal connections to the right atrium.

  In the right atrium, oxygen-rich (red) blood from the pulmonary veins mixes with venous (bluish) blood from the body. Part of this mixture passes through the atrial septum (atrial septal defect) into the left atrium. From there it goes into the left ventricle , to the aorta and out to the body. The rest of the poorly oxygenated mixture flows through the right ventricle, into the pulmonary artery and on to the lungs. The blood passing through the aorta to the body doesn't have enough oxygen, which causes the child to look blue (cyanotic) .

  This defect must be surgically repaired in early infancy. The pulmonary veins are reconnected to the left atrium and the atrial septal defect is closed. When surgical repair is done in early infancy, the long-term outlook is very good. Still, lifelong follow-up is needed to make certain that any remaining problems, such as an obstruction in the pulmonary veins or irregularities in heart rhythm, are treated properly. Lifelong follow-up is important to make certain that a blockage doesn't develop in the pulmonary veins or where they're attached to the left atrium. Heart rhythm irregularities (arrhythmias) also may occur at any time after surgery.

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In hypoplastic left heart syndrome, the left side of the heart - including the aorta , aortic valve, left ventricle and mitral valve - is underdeveloped. Blood returning from the lungs must flow through an opening in the wall between the atria , called an atrial septal defect. The right ventricle pumps the blood into the pulmonary artery , and blood reaches the aorta through a patent ductus arteriosus (see above).

The baby often seems normal at birth, but will come to medical attention within a few days of birth as the ductus closes. Babies with this syndrome become ashen, have rapid and difficult breathing and have difficulty feeding. This heart defect is usually fatal within the first days or months of life without treatment.

Although this defect is not correctable, some babies can be treated with a series of operations, or with a heart transplant. Until an operation is performed, the ductus is kept open by intravenous (IV) medication. Because these operations are complex and different for each patient, you need to discuss all the medical and surgical options with your child's doctor. Your doctor will help you decide which is best for your baby.

If you and your child's doctor elect to undergo surgery, the surgery will be performed in several stages. The first stage, called the Norwood procedure, allows the right ventricle to pump blood to both the lungs and the body. It must be performed soon after birth. The final stage(s) has many names including bi-directional Glenn, Fontan operation and lateral tunnel. These operations create a connection between the veins returning blue blood to the heart and the pulmonary artery. The overall goal of the operation is to allow the right ventricle to pump only oxygenated blood to the body and to prevent or reduce mixing of the red and blue blood. Some infants require several intermediate operations to achieve the final goal.

Some doctors will recommend a heart transplant to treat this problem. Although it does provide the infant with a heart that has normal structure, the infant will require lifelong medications to prevent rejection. Many other problems related to transplants can develop, and you should discuss these with your doctor.

Children with hypoplastic left heart syndrome require lifelong follow-up by a pediatric cardiologist for repeated checks of how their heart is working. Virtually all the children will require heart medicines.

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• Valvular heart disorders
• American Heart Association website on congenital cardiovascular disease
• The AHA Web site also has information on congenital heart defects in Spanish.
• Congenital Cardiovascular Disease

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