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hole in the heart








Contents
  • Types of holes in the heart
  • Causes
  • Symptoms
  • Diagnosis and staging
  • Treatment
  • Living with
  • A hole in the heart is a type of simple congenital heart defect – a problem with the heart's structure that is present at birth. Congenital heart defects change the normal flow of blood through the heart.

    The heart has two sides, separated by an inner wall called the septum. With each heartbeat, the right side of the heart receives oxygen-poor blood from the body and pumps it to the lungs. The left side of the heart receives oxygen-rich blood from the lungs and pumps it to the body. The septum prevents mixing of blood between the two sides of the heart.

    Some babies are born with a hole in the upper or lower septum. A hole in the septum between the heart's upper two chambers (the atria) is called an atrial septal defect (ASD). A hole in the septum between the heart's lower two chambers (the ventricles) is called a ventricular septal defect (VSD).

    A hole in the septum can allow blood to pass from the left side of the heart to the right side. This means that oxygen-rich blood can mix with oxygen-poor blood, causing the oxygen-rich blood to be pumped to the lungs a second time.

    Over the past few decades, the diagnosis and treatment of ASDs and VSDs have greatly improved. As a result, a child with a simple heart defect can grow to adulthood and live a normal, active, and productive life because his or her heart defect closes on its own or has been repaired.


    Types of holes in the heart

    Atrial septal defect

    An atrial septal defect (ASD) is a hole in the part of the septum that separates the atria (upper chambers of the heart). This heart defect allows oxygen-rich blood from the left atrium to flow across the atrial septum into the right atrium instead of flowing down to the left ventricle as it should. This is inefficient because oxygen-rich blood gets pumped back to the lungs, where it has just been, instead of going to the body.

    normal heart and heart with atrial septal defect (ASD)
    Figure A shows the normal anatomy and blood flow of the interior of the heart. Figure B shows a heart with an atrial septal defect, which allows oxygen-rich blood from the left atrium to mix with oxygen-poor blood from the right atrium.

    An ASD can be small or large. Small ASDs allow only a little blood to flow from one atrium to the other. Small ASDs don't affect the way the heart works and therefore don't need any special treatment. Many small ASDs close on their own as the heart grows during childhood.

    Medium to large ASDs allow more blood to leak from one atrium to the other, and they are less likely to close on their own. Most children with ASDs have no symptoms, even if they have large ASDs.

    There are three major types of ASD:
    • Secundum. This defect is in the middle of the atrial septum. It's the most common form of ASD. About 8 out of every 10 babies born with ASD have secundum defects. At least half of all secundum ASDs close on their own. This is less likely if the defect is large.

    • Primum. This defect is in the lower part of the atrial septum. It often occurs along with abnormalities in the heart valves that connect the upper and lower heart chambers. Primum defects aren't very common. This type of defect doesn't close on its own.

    • Sinus venosus. This defect is in the upper part of the atrial septum, near where a large vein (the superior vena cava) brings oxygen-poor blood from the upper body to the right atrium. Sinus venosus is a rare defect. Sinus venosus defects don't close on their own.

    Long-term effects of atrial septal defects that aren't repaired

    Over time, the extra blood flow to the right side of the heart and the lungs may cause problems for a heart that has an ASD. Usually, most of these problems don't show up until adulthood, often around age 30 or later. They are rare in infants and children. These possible problems include:
    • Right heart failure. The right side of the heart has to work harder to pump extra blood to the lungs. Over time, the heart may become tired from this extra work and not pump efficiently.

    • Arrhythmias (irregular heartbeats). Extra blood flowing into the right atrium through an ASD can cause the atrium to stretch and enlarge. Over time, this can lead to problems with the heart's rhythm. When this occurs, an arrhythmia can develop, with signs or symptoms such as palpitations (a feeling that your heart has skipped a beat or is beating too hard) or a rapid heartbeat.

    • Stroke. Usually, the lungs filter out small clots that can form on the right side of the heart. Sometimes a blood clot formed on the right side of the heart can pass through an ASD to the left side and be pumped out to the body. A clot like this can travel to an artery in the brain, blocking blood flow through it and causing a stroke. This doesn't occur in childhood.

    • Pulmonary arterial hypertension (PAH). PAH is high blood pressure in the arteries in the lungs. Over time, high blood pressure in the lungs can damage the arteries and the small blood vessels in the lungs. They thicken and become stiff, making it harder for blood to flow through them.
    These problems develop over many years and don't occur in children. They also are rare in adults because most ASDs either close on their own or are repaired in early childhood.


    Ventricular septal defect

    A ventricular septal defect (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 across the heart into the right ventricle instead of flowing up into the aorta and out to the body as it should.

    ventricular septal defect
    Figure A shows the normal anatomy and blood flow of the interior of the heart. Figure B shows two common locations of ventricular septal defects. The defect allows oxygen-rich blood from the left ventricle to mix with oxygen-poor blood in the right ventricle.

    An infant born with a VSD may have a single hole or more than one hole in the wall that separates the two ventricles. The defect also may occur by itself or with other congenital heart defects. Doctors classify VSDs based on the:
    • Size of the defect.
    • Location of the defect.
    • Number of defects.
    • Presence or absence of a ventricular septal aneurysm – a thin flap of tissue on the septum. This tissue is harmless and can help a VSD close on its own.
    VSDs can be small or large. A small VSD doesn't cause problems and may often close on its own. Because small VSDs allow only a small amount of blood to flow between the ventricles, they're sometimes called restrictive VSDs. Small VSDs don't cause any symptoms.

    Medium VSDs are less likely than small defects to close on their own. They may require surgery to close and may cause symptoms during infancy and childhood.

    Large VSDs allow a large amount of blood to flow from the left ventricle to the right ventricle and are sometimes called nonrestrictive VSDs. A large VSD is less likely to close completely on its own, but it may get smaller over time. Large VSDs often cause symptoms in infants and children, and surgery is usually needed to close them.

    VSDs are found in different parts of the septum.
    • Membranous VSDs are located near the heart valves. They can close at any time.
    • Muscular VSDs are found in the lower part of the septum. They are surrounded by muscle, and most close on their own during early childhood.
    • Inlet VSDs are located close to where blood enters the ventricles. They are less common than membranous and muscular VSDs.
    • Outlet VSDs are found in the part of the ventricle where the blood leaves the heart. This is the rarest type of VSD.

    Long-term effects of large ventricular septal defects that aren't repaired

    A moderate to large VSD can cause:
    • Heart failure. Infants with large VSDs may develop heart failure because the left side of the heart pumps blood into the right ventricle in addition to its normal work of pumping blood to the body. The increased workload on the heart also increases the heart rate and the body's demand for energy.

    • Growth failure, especially in infancy. A baby may not be able to eat enough to keep up with his or her body's increased energy demands. As a result, the baby may lose weight or fail to grow and develop normally.

    • Arrhythmias (irregular heartbeats). The extra blood flowing through the heart can cause areas of the heart to stretch and enlarge. This can disturb the normal electrical activity of the heart, leading to fast and irregular heart rhythms.

    • Pulmonary arterial hypertension (PAH). The high pressure and high volume of extra blood pumped through a large VSD into the lungs can cause scarring of the delicate arteries in the lungs. Today, PAH rarely develops because most large VSDs are repaired in infancy.

    What causes holes in the heart?

    Mothers of children born with an atrial septal defect (ASD), a ventricular septal defect (VSD), or another type of heart defect often think that they did something wrong during the pregnancy to cause the problem. However, most of the time, doctors don't know why these congenital heart defects develop.

    Heredity may play a role in some heart defects. For example, a parent who has a congenital heart defect is slightly more likely than other people to have a child with the problem. In very rare cases, more than one child in a family is born with a heart defect. Children with genetic defects often have congenital heart defects. An example of this is Down's syndrome – half of all babies with Down syndrome have congenital heart defects.

    Scientists continue to search for the causes of congenital heart defects.


    What are the signs and symptoms of holes in the heart?


    Atrial septal defect

    A heart murmur (an extra flow sound associated with the heartbeat) is the most common sign of an atrial septal defect (ASD). Often, it's the only sign. However, not all murmurs are a sign of a congenital heart defect. Many healthy children have heart murmurs, which are innocent, normal sounds of blood flow through the heart. A doctor can tell by listening whether a murmur is a normal flow sound or a sign of a heart problem. Many babies born with ASDs have no signs or symptoms.

    If a large ASD isn't repaired, the extra blood flow to the right side of the heart can eventually damage the heart and lungs, causing heart failure. This doesn't occur until adulthood. Signs and symptoms of heart failure can include:
    • Fatigue or tiring easily during exercise or activity
    • Shortness of breath
    • A buildup of blood and fluid in the lungs
    • A buildup of fluid in the feet, ankles, and legs

    Ventricular septal defect

    A heart murmur is usually present in ventricular septal defect (VSD) and may be the first and only sign of this defect. The heart murmur is often present right after birth in many infants, but it may not be heard until the baby is 6 to 8 weeks old.

    Most newborns who have VSDs don't have heart-related symptoms. However, a baby with a medium or large VSD can develop heart failure. Signs and symptoms of heart failure usually appear during the baby's first 2 months of life. The signs and symptoms of heart failure from VSD are similar to those listed above for ASD, but they occur in infancy.

    The major sign of heart failure is difficulty feeding and poor growth. VSD symptoms are rare after infancy because the defect either decreases in size on its own or is repaired.


    How are holes in the heart diagnosed?

    Holes in the heart are usually diagnosed based on results from a physical exam and special tests. The exam findings for an atrial septal defect (ASD) often aren't obvious, so the diagnosis is sometimes not made until later childhood or even adulthood. A ventricular septal defect (VSD) has a very distinct heart murmur, so this diagnosis is usually made in infancy.


    Specialists involved

    Doctors who specialize in heart problems are called cardiologists. Pediatric cardiologists take care of babies and children who have heart problems. Other specialists who treat heart defects include cardiac surgeons (doctors who repair heart defects using surgery).


    Physical exam

    During a physical exam, the doctor:
    • Listens to the child's heart and lungs with a stethoscope
    • Looks for signs of a heart defect, such as a heart murmur or signs of heart failure

    Diagnostic tests and procedures

    The doctor will order several tests to diagnose an ASD or VSD. These tests also will help the doctor determine the location and size of the defect.


    Echocardiography

    This test, which is harmless and painless, uses sound waves to create a moving picture of the heart. During echocardiography, ultrasound waves bounce off the structures of the heart, and then a computer converts them into pictures on a video screen. The test allows the doctor to clearly see any problem with the way the heart is formed or the way it's working.

    Echocardiography is an important test for diagnosing a hole in the heart and for following the problem over time. This test shows problems with the heart's structure and how the heart is reacting to these problems. Echocardiography helps the cardiologist decide whether and when treatment is needed.


    EKG

    An EKG (electrocardiogram) detects and records the electrical activity of the heart. This simple and painless test is used to assess the heart rhythm. An EKG shows how fast the heart is beating and whether the heart's rhythm is steady or irregular. It also can detect enlargement of one of the heart's chambers, which can help to diagnose a heart defect.


    Chest X-ray

    A chest X-ray takes a picture of the heart and lungs. It can show whether the heart is enlarged or whether the lungs have extra blood flow or extra fluid, which can be a sign of heart failure.


    Pulse oximetry

    Pulse oximetry shows how much oxygen is in the blood. A sensor is placed on the fingertip or toe (like an adhesive bandage). The sensor is attached to a small computer unit, which displays a number that indicates how much oxygen is in the blood.


    Cardiac catheterization

    During cardiac catheterization, a thin, flexible tube called a catheter is put into a vein in the arm, groin (upper thigh), or neck and threaded to the heart. A dye that can be seen on an X-ray is injected through the catheter into a blood vessel or a chamber of the heart. This allows the doctor to see the flow of blood through the heart and blood vessels on the X-ray image.

    Cardiac catheterization also can be used to measure the pressure inside the heart chambers and blood vessels and can determine whether blood is mixing between the two sides of the heart. It's also used to repair some heart defects.


    How are holes in the heart treated?

    Although many holes in the heart don't need treatment, some do. These days, most holes in the heart that need treatment are repaired in infancy or early childhood. Sometimes, adults are treated for holes in the heart if problems develop.

    The treatment your child receives depends on the type, location, and size of the hole. Other factors include your child's age, size, and general health.


    Treating atrial septal defect

    Periodic checkups are done to see whether the defect closes on its own. About half of all ASDs close on their own over time, and about 20 percent close within the first year of life. Your child's doctor will recommend how often your child should be checked. For an ASD, frequent checkups aren't needed. When treatment of an ASD is required, it involves catheter or surgical procedures to close the hole.


    Catheter or surgical procedures to repair ASD

    Doctors often decide to close an ASD in children who still have medium to large holes by the time they are 2 to 5 years old.

    Catheter procedure. Until the early 1990s, surgery was the usual method for closing all ASDs. Now, thanks to medical advances, catheter procedures can be used to close secundum ASDs, which are the most common type of ASD. This procedure is done under general anesthesia, so the child sleeps throughout and doesn't feel any pain.

    During the procedure, the doctor inserts a catheter (a thin, flexible tube) into a vein in the groin (upper thigh) and threads it to the heart's septum. The catheter has a tiny umbrella-like device folded up inside it. When the catheter reaches the septum, the device is pushed out of the catheter and positioned so that it plugs the hole between the atria. The device is secured in place and the catheter is withdrawn from the body. Within 6 months, normal tissue grows in and over the device. There is no need to replace the closure device as the child grows.

    Doctors often use echocardiography or a transesophageal echocardiography (TEE) as well as angiography to guide them in threading the catheter to the heart and closing the defect. A TEE is a special type of echocardiography that takes pictures of the heart through the esophagus (the tube leading from the mouth to the stomach).

    Catheter procedures are much easier than surgery on patients because they involve only a needle puncture in the skin where the catheter is inserted. This means that recovery is faster and easier. The outlook for children having this procedure is excellent. Closures are successful in more than 9 out of 10 patients, with no significant leakage. Rarely, a defect is too large for catheter closure, so surgery is needed.

    Surgery. Open-heart surgery is generally done to repair primum or sinus venosus ASDs. General anesthesia is used so the child will sleep through the operation and not feel any pain.

    During this procedure, the surgeon makes an incision in the chest to reach the ASD and repairs the defect with a special patch that covers the hole. The child is placed on a heart-lung bypass machine so that the heart can be opened to perform the operation.

    The outlook for children after ASD surgery is excellent. On average, children spend 3 to 4 days in the hospital before going home. Complications, such as bleeding and infection, from ASD surgery are very rare. Some children may develop inflammation of the outer lining of the heart, causing fluid to collect around the heart in the weeks after surgery. This is a reaction to the heart operation and usually resolves with medicine.

    While in the hospital, the child is given medicines as needed to reduce pain or anxiety. The doctors and nurses at the hospital teach parents how to care for the child at home. They will talk about preventing blows to the chest as the incision heals, limiting activity while the child recovers, bathing, scheduling followup appointments with the doctor, and determining when the child can resume regular activities.


    Treating ventricular septal defect

    The doctor may choose to monitor and observe a child with VSD who doesn't have symptoms of heart failure. This means regular checkups and tests to see whether the defect closes on it own or gets smaller. More than half of VSDs eventually close, usually by the time a child is in preschool. Your child's doctor will recommend how often your child should be checked, ranging from monthly checkups to checkups every 1 or 2 years.

    When treatment for VSD is required, options include extra nutrition and surgery to close the VSD.

    Surgical treatment is needed if a child's VSD:
    • Is large
    • Is causing your child to have symptoms
    • Is medium-sized and is causing enlargement of the heart chambers
    • Affects the aortic valve

    Extra nutrition

    Some infants with VSDs don't grow and develop or gain weight as they should. These infants usually:
    • Have large VSDs
    • Are born prematurely
    • Tire easily during feeding
    Doctors usually recommend extra nutrition or special feedings for these infants. These feedings are high-calorie formulas or breast milk supplements that give the baby extra nourishment.

    In some cases, tube feeding is needed. Food is given through a small tube that is placed through the nose into the stomach. Tube feeding can add to or take the place of bottle feeding. This treatment is usually temporary, because a VSD that causes symptoms will likely need surgery.


    Surgery to repair VSDs

    Today, most doctors recommend surgery to close a large VSD that's causing symptoms or hasn't closed by 1 year of age. Surgery may be required earlier if:
    • The child fails to gain weight
    • Medicines are required to control the symptoms of heart failure
    Rarely, a medium-sized VSD that's causing enlargement of the heart chambers is treated with surgery after infancy. However, most VSDs that need surgery are repaired in the first year of life.


    Living with holes in the heart

    The outlook for children with atrial septal defects (ASDs) and ventricular septal defects (VSDs) is excellent. Advances in treatment mean that most children with these heart defects have normal, active, and productive lives with no decrease in lifespan.

    Many children with these defects need no special care or only occasional checkups with a cardiologist (a doctor who specializes in heart problems) as they go through childhood and adult life.


    Living with an atrial septal defect

    Small ASDs often close on their own, and children with these heart defects don't have any problems or need treatment. Children and adults with small ASDs that don't close and don't cause symptoms are healthy and don't need treatment.

    Many others with ASDs that don't close undergo procedures to close the hole and prevent possible long-term complications. Children recover well from these procedures and lead normal, healthy lives. Adults also do well after closure procedures.


    Medical needs

    Arrhythmias. The risk of arrhythmias (irregular heartbeats) increases before and after surgery. Adults with ASDs who are older than 40 years are especially likely to have arrhythmias. People who had arrhythmias before surgery are more likely to have them after surgery.

    Followup care. Regular followup care into adult life is advised for those who have had:
    • An ASD repaired as an adult
    • Arrhythmias before and after surgery
    • An ASD repaired with a catheter procedure
    • High blood pressure in the pulmonary artery at the time of surgery
    Antibiotics. Some heart defects and their repairs can increase the risk of bacterial endocarditis, a serious infection of the heart valves or lining of the heart. Talk with your doctor and dentist about whether antibiotics are necessary before medical procedures, such as surgery or dental procedures/cleaning, that could allow bacteria to enter the bloodstream and cause endocarditis. ASDs aren't associated with the risk of endocarditis, except in the 6 months after repair (for both catheter procedures and surgery).


    Special considerations for children and teens

    Activity. Children with a repaired or closed ASD have no restrictions on their activity.

    Growth and development. Children with ASDs don't have growth or development problems.

    Regular health care. Your child should see his or her regular doctor for routine health care.

    Additional surgery or procedures. When a child has an ASD, but no other heart defect, additional surgery isn't needed.


    Special considerations for adults

    Recovery from surgical repair of an ASD. When an ASD is repaired in adult life, the cardiologist or surgeon will explain what to expect during the recovery period and when to return to driving, working, exercising, and other activities.


    Living with a ventricular septal defect

    Children with small VSDs have no symptoms and need only rare followup with a cardiologist. To protect these children from endocarditis, they need antibiotics before dental work or any other procedure where bacteria enter the bloodstream. Children and adults who have had successful repair of a VSD and have no other congenital heart defects can expect to lead normal, healthy, and active lives.


    Medical needs

    Sometimes problems and risks remain after surgical closure. They include:
    • Arrhythmias (irregular heartbeats). Serious and frequent arrhythmias require regular medical followup. The risk of arrhythmia is greater if surgery is done later in life.

    • Residual or remaining VSD. This is usually due to a leak at the edge of the patch used to close the hole. These VSDs tend to be very small and don't cause problems. They very rarely require another operation.
    Antibiotics. People with VSDs are at increased risk of bacterial endocarditis. Antibiotic treatment to prevent bacterial endocarditis is recommended for 6 months after VSD surgery. Residual VSDs or small VSDs that don't need surgery require lifelong treatment with antibiotics before dental work or any procedure in which bacteria usually enter the bloodstream. Your cardiologist can advise you about antibiotics.


    Special considerations for children and teens

    Activity. There should be no activity restrictions on a child with a small VSD that doesn't need surgery, or after recovery from VSD repair. Be sure to check with your child's doctor about whether your child can take part in sports.

    Growth and development. Your pediatrician or family doctor checks your child for growth and development at each routine checkup. Babies with large VSDs may not grow as quickly as other infants. These babies usually catch up after the VSD is closed.

    Regular health care. Your child should see his or her regular doctor for routine health care.

    Additional surgery or procedures. Teens and young adults rarely need additional surgery once a VSD closes or is repaired.


    Related categories

       • HEART TOPICS
       • HEALTH AND DISEASE