atrial septal defect (hole in the heart)
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.
Atrial septal defect (ASD) is a hole in the wall (septum) that separates the two upper chambers (atria) of the heart. ASD, or "hole in the heart," allows blood to flow from one atrium to the other, usually from the left side to the right side. This causes extra blood flow in the right atrium, in the right ventricle, and to the lungs.
In a normal heart, oxygen-poor (blue) blood returns from the body to the right atrium. From the right atrium, the blue blood flows to the right ventricle – one of the two lower chambers of the heart – and is pumped to the lungs to pick up oxygen. After traveling through the lungs, the blood is now oxygen-rich and red. The red blood returns from the lungs to the left atrium and goes to the left ventricle, where it is pumped to the body. The right and left sides of the heart are normally completely separated by the septum. The septum keeps the blue blood from mixing with the red blood. ASD is the second most common congenital heart defect.
Effects of atrial septal defect
Over time, the extra blood flow to the right side of the heart and the lungs can cause:
Usually, most of these effects don't show up until adulthood, often around age 30 or later. They are rare in infants and children.
An ASD is classified by its size and location.
The size of an ASD can range from small to large.
Three major types of ASD exist, based on the location of the defect on the septum:
Half of all ASDs close without treatment. When treatment is necessary, it is usually successful. Once the defect has closed or has been repaired, most children:
What causes atrial septal defect?
There is no single, known cause of atrial septal defect (ASD).
Heredity (genetics) may play a role in ASD. In some cases, it may be due to a difference in one or more genes.
What are the signs and symptoms of atrial septal defect?
The major signs and symptoms of atrial septal defect (ASD) are:
Most children with ASD don't have symptoms, even with a large ASD. However, some children and adults with ASD may develop symptoms which include:
In most people with ASD who develop symptoms, the symptoms don't develop until adulthood.
How is atrial septal defect diagnosed?
Atrial septal defect (ASD) is diagnosed using a medical history, a physical exam, and tests. ASD is usually found in infants or children during a routine physical exam. However, some people with ASD are not diagnosed until adulthood.
Medical and family history
Your child's doctor will ask you about:
The doctor will listen to your child's heart with a stethoscope for a heart murmur. The doctor will also check for signs of increased blood flow to the lungs.
Your child's doctor may order one or more tests to diagnose ASD. These tests also help the doctor decide the type and size of the defect:
How is atrial septal defect treated?
The goals of treating atrial septal defect (ASD) include:
Types of treatment include:
Your child's doctor will discuss treatment options with you and will consider your family's preferences when making treatment decisions.
Monitoring and observation
Periodic checkups are done to see if the defect closes on its own. About half of all ASDs close on their own, and many close within the first year of life. Your child's doctor will recommend how often your child should be checked, ranging from weekly checkups to checkups every 1 or 2 years.
Children with no symptoms usually don't need any medicines. Children who develop symptoms usually are referred for closure of the defect. They may need medicines to control the symptoms until the defect can be closed. Medicines include:
Antibiotics may be given to prevent bacterial endocarditis, an infection of the inner lining and valves of the heart. The antibiotic is given in a single dose 1 hour before a dental visit or surgical procedure. This treatment is usually needed for only 6 months after ASD surgery or a catheter procedure. The antibiotics are used only to prevent infection and not to treat the ASD.
Closure of the atrial septal defect
Closure may be recommended for infants and children who develop symptoms such as fast breathing or slow growth. Closure is also commonly performed for children with moderate to large ASDs that remain at 3 to 5 years of age. Sometimes, doctors recommend closure of smaller defects found in older children and adults.
Until recently, surgery was the usual method for closing an ASD. General anesthesia is used so the child will sleep through the procedure and not feel any discomfort.
Complications, such as bleeding and infection, from ASD surgery are rare and short term. Some people may develop swelling of the outer lining of the heart, causing fluid to collect around the heart. This usually resolves with medicine.
Your child may need to take medicine temporarily to help with discomfort.
After ASD surgery, your child will spend a few days in the intensive care unit or in a regular hospital room. Most children go home within 4 days after the surgery.
While in the hospital, your child will be given medicines to reduce pain or anxiety as needed. The doctors and nurses at the hospital will teach you how to care for your child at home. They will talk to you about:
The outlook for children after surgery is usually excellent. Your child will most likely have little pain or discomfort from the incision. After recovering, your child should be able to take part in normal activities.
Procedures using catheters
A procedure that uses a catheter to close the ASD with a special closure device (septal occluder) is a recent but increasingly used option. Catheters are thin, flexible tubes used in cardiac catheterization.
The advantages of such procedures are that they:
Closure with a catheter can't be done for every type of ASD. A catheter can be used with secundum defects (that is, those located near the middle of the septum). It can't be used with defects so large that there is not enough surrounding tissue to anchor the device.
The catheter procedure is done under general anesthesia, so your child will sleep through the procedure and not feel any discomfort. During the procedure, the doctor:
Within 6 to 8 weeks, normal tissue grows in and over the device. There is no need to replace the closure device as the child grows.
The outlook for children having this procedure is excellent. Closures are successful in more than 9 out of 10 patients, with no significant leakage. Because the device is relatively new, what is not known is whether there are any long-term problems with the device compared to surgery.
Living with atrial septal defect
Smaller atrial septal defects (ASDs) often close on their own, and children don't have any problems or need treatment. Children and adults with small ASDs that cause no symptoms may be healthy and feel well with no treatment. However, many others undergo closure procedures to prevent potential long-term complications. Most children recover well from closure procedures and live normal, healthy lives. Adults also usually do well after closure procedures.
Arrhythmias. The risk of arrhythmias (irregular heartbeats) increases before and after surgery. Adults older than 40 years are especially likely to have arrhythmias. People who had arrhythmias before surgery are more likely to have them after surgery.
Regular follow-up care is advised for those who had:
Special needs for children
Activity. Children with a repaired or closed ASD have no restrictions on their activity. Children who are being monitored and treated with medicines may have some restrictions. Consult your child's doctor for activity guidelines.
Growth and development
Children with ASD have very few growth and development problems. If your child has slow growth, he or she will catch up after the ASD has closed or been repaired.
Antibiotics before dental care
Children with just ASD don't need antibiotics for dental care. The doctor may recommend antibiotics for dental care for the first 6 months after a closure procedure. The antibiotic is given in a single dose 1 hour before the dental visit. The antibiotic is given to prevent bacteria from entering the bloodstream and causing an infection called endocarditis.
Regular health care
Your child should see his or her regular doctor for routine health care.
Special needs for adults
Some adults have their ASDs closed to prevent or minimize symptoms and complications. After ASD closure, full recovery takes longer for adults than for children. You may benefit from a cardiac rehabilitation program as you recover from your ASD closure. Talk with your doctor about when it is all right for you to drive, return to work, resume exercising, and do other activities.