For children with very small ASDs, the ASD closes on its own about 90% of the time. However, most other ASDs must be closed. Fortunately, medical technology has progressed so that most ASDs that must be treated can be closed in a cardiac catheterization lab without open-heart surgery. Some ASDs must still be closed with open-heart surgery.
What Causes an ASD?
ASDs occur during fetal development. During the first weeks after conception, the heart develops from a large tube, dividing into sections that will eventually become the walls and chambers. If a problem occurs during this process, a hole in the atrial septum may result.
In some cases, the tendency to develop ASD may have a genetic basis, occurring either because of a defect in a gene or an abnormality in a chromosome, but these causes are extremely rare. Others may be related to certain maternal illnesses during pregnancy. For the vast majority of children with a defect, however, there's no clear reason as to why ASD develops.
Signs and Symptoms
The size of an ASD and its location in the heart will determine the extent to which a child will experience symptoms of the ASD. Most children who have ASDs are asymptomatic, which means that they seem healthy and appear to have no symptoms. Generally, kids with an ASD feel well and grow and gain weight normally. Infants and children with larger, more severe ASDs, however, may possibly show some of the following signs or symptoms:
- poor appetite
- poor growth
- fatigue
- shortness of breath
- lung problems and infections, such as pneumonia
If an ASD is left untreated, long-term side effects may develop later in life. These include an abnormal heart rhythm (known as an atrial arrhythmia) and problems in heart function (how well the heart pumps blood) with possible heart failure. As kids with ASDs get older, they may also be at an increased risk for stroke.
Pulmonary hypertension (high blood pressure in the lungs) may also be a concern in people with larger untreated ASDs, but it's rare. Larger defects allow more blood to pass through the hole in the septum. Left untreated, this increased blood flow can result in changes in the blood vessels that will raise the pressure in the arteries of the lungs over time. In the long term, this can lead to a condition known as Eisenmenger syndrome, a rare but very severe form of pulmonary artery hypertension that causes fatigue, difficulty breathing, a bluish tinge to the skin, and ultimately, death. Fortunately, modern treatment methods mean that this irreversible, disabling condition has become a rare complication of ASD.
People with some types of heart defects, including certain rarer forms of ASD, are at greater risk of developing bacterial endocarditis, an infection of the inner surface of the heart. Most children with ASDs don't need to worry about bacterial endocarditis. However, in a very few cases, a child with an ASD may need to take preventive antibiotics before having dental work or other surgical procedures. (During these procedures, bacteria can make their way into the bloodstream, increasing the risk of infection.) Your child's doctor will tell you if your child has this type of ASD and the precautions you'll need to take.
Fortunately, most kids with ASD are treated long before the heart defect causes physical symptoms. Because of the complications that ASDs can cause later in life, pediatric cardiologists often recommend closing ASDs early in childhood to prevent damage to the heart, lungs, and other body organs.
Diagnosis and Treatment
Generally, a child's doctor hears the heart murmur caused by ASD during a routine checkup or physical examination. ASDs are not always diagnosed as early in life as other types of heart murmurs, such as ventricular septal defect (a hole in the wall between the two ventricles). The murmur caused by an ASD is not as loud and may be more difficult to hear than other types of heart murmurs, so it may be diagnosed any time between infancy and adolescence. Sometimes it can even be discovered in adulthood.
If a child's doctor hears a murmur and suspects a heart defect, the child may then be referred to a pediatric cardiologist, a doctor who specializes in diagnosing and treating childhood heart disease.
The doctor will ask a child's parent about the child's medical and family history before examining the child and listening to the heart. If the cardiologist thinks a child might have an ASD, he or she may order one or more of the following tests:
- chest X-ray, which produces an image of the heart and surrounding organs
- electrocardiogram (EKG), which records the electrical activity of the heart and can indicate volume overload of the right side of the heart
- echocardiogram (echo), which uses sound waves to produce a picture of the heart and to visualize blood flow (this is often the primary tool used to diagnose ASD)
Once a child is diagnosed with an ASD, treatment will depend on the child's age and the size, location, and severity of the defect.
A child with a small defect that causes no symptoms may simply need to visit a pediatric cardiologist regularly to ensure that there are no problems; often, small defects will close spontaneously without any treatment during the first years of life. In general, a child with a small ASD won't require restrictions on his or her physical activity.
In most children with ASD, though, doctors must close the defect if it has not closed on its own by the time a child begins attending school.
Depending on the position of the ASD in the atrial septum, many children with ASD can have it corrected with a procedure known as cardiac catheterization. In this procedure that takes place in a cardiac catheterization lab, a thin, flexible tube called a catheter is inserted into a blood vessel in the leg that leads to the heart. A cardiologist guides the tube into the heart and inserts a special device, commonly shaped like a dumbbell, into the hole in the septum. The device is designed to flatten against the septum to close and permanently seal the ASD. In the beginning, the natural pressure in the heart holds the device in place. Over time, the normal tissue of the heart grows over the device and covers it entirely.
Because there is a small risk of blood clots forming on the closure device while new tissue heals over it, children who undergo cardiac catheterization may need to be on aspirin or other medications for several months after the procedure to prevent clots from forming.
If surgical repair for ASD is necessary, a child will typically undergo open-heart surgery. After general anesthesia is administered, a surgeon makes a cut in the chest and either closes the atrial septal defect with stitches alone or sews a patch of natural or synthetic surgical material (such as Gore-Tex) over the defect. Eventually, the tissue of the heart heals over the patch or stitches, and by 6 months after the surgery, the hole will be completely covered with tissue.
For 6 months following catheterization or surgical closure of an ASD, preventive antibiotics are recommended before routine dental work or surgical procedures to prevent bacterial endocarditis. Once the tissue of the heart has healed over the closed ASD (about 6 months to a year after surgery), most people who have had their ASDs corrected no longer need to worry about bacterial endocarditis.
Your doctor will discuss other possible risks and complications with you prior to the procedure. But after repair and adequate time for healing, children with ASD rarely experience further symptoms or disease. Children who undergo cardiac catheterization to close an ASD will have a small needle prick in their groin area and will usually spend the night in the hospital after the procedure, but can return home shortly afterward. Children who have had a catheterization procedure should also be kept out of gym class or sports practice for a week; after a week, they can usually return to their normal physical activities, with their doctor's OK.
Children who undergo surgery for their ASDs usually go home after a few days in the hospital, if there are no complications. After surgical ASD repair, the main medical concern is the healing of the chest incision. The child's incision will be tender and sore, so a pain reliever like acetaminophen (such as Tylenol) or ibuprofen (such as Advil or Motrin) may be recommended to relieve pain around the surgery site. In general, the younger patients are when they have their surgical repairs, the less pain they will have during recovery. It takes about 6 weeks for chest incision to heal. Because infants and children who undergo surgery for ASDs are developing and growing rapidly, the biggest problem that many parents face is keeping their active children from reopening the incision site.
To minimize an infant's or child's risk of injury, it may be necessary for a parent or other caregiver to provide one-on-one care for at least 6 weeks after surgery, and you or your child's caregiver should ensure that your child plays quietly with supervision. Blows to the chest that may injure the incision should be avoided. Six weeks after surgery, your child should be recovered and able to return to normal activities.
Open-heart surgery does leave a permanent scar on the chest. Your child may feel numbness, itchiness, tightness, and burning around the incision, but these feelings shouldn't be severe. If you notice that your child seems self-conscious about the scar, talk to him or her about it. Most children, especially adolescents, don't like feeling different from their friends and may need some reassurance at first. If the scar really seems to be affecting your child's self-esteem, you might also ask the doctor about over-the-counter concealers or other ways to minimize the scar once it has healed.
In the weeks following surgery or cardiac catheterization, your child's doctor will check on your child's progress. Your child may undergo another echocardiogram to make sure that the heart defect has closed completely. Children who have undergone ASD repair will also generally have a checkup 1 year after the procedure. If the ASD has properly closed and healed at 1 year, then the child is considered completely cured.
Most children who undergo treatment for ASDs recover quickly - you may even notice that within a few weeks of treatment, your child is eating more and is more active than before surgery. However, some signs and symptoms may indicate a problem. If your child is having trouble breathing, call your child's doctor or take your child to the emergency department immediately. Other symptoms that may indicate a problem include:
- a bluish tinge or color (cyanosis) to the skin around the mouth or on the lips and tongue
- poor appetite or difficulty feeding
- failure to gain weight or weight loss
- listlessness or decreased activity level
- prolonged or unexplained fever
- increasing pain, tenderness, or pus oozing from your child's incision
Call your child's doctor if you notice any of these signs in your child after closure of the ASD.
Any time a child is diagnosed with a heart condition, it can be scary. But the good news is that most children who've had an ASD corrected have a normal life expectancy and go on to live otherwise healthy lives. Your child will be back to doing the things he or she loves in no time at all, and the ASD will be a thing of the past.
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