A ventricular septal defect (VSD) is a congenital heart defect. This means that your baby is born with it. A VSD is a hole in the wall (septum) that separates the two lower chambers of the heart (right and left ventricles). VSDs are the most common type of congenital heart defect.

The heart has four chambers: two upper (atria) and two lower (ventricles). Blood that is high in oxygen flows from the left atrium to the left ventricle and out to the body, where the vital organs use the oxygen. Blood with less oxygen flows from the right atrium to the right ventricle and out to the lungs. In the lungs it picks up more oxygen.

Normally. the septal wall prevents the mixing of blood between the two ventricles of the heart. A VSD allows oxygen-rich (red) blood to pass abnormally from the left ventricle through the opening in the septum. Then it mixes with oxygen-poor (blue) blood in the right ventricle.

A large VSD can cause high pressure in the blood vessels in the lungs. The higher pressure can lead to lower oxygen levels in the body. If your child has a larger VSD, they may need some type of repair. Babies and children with larger VSDs often have symptoms, such as breathing faster and harder than normal. Very small holes in the ventricular septum may not let much blood pass between the ventricles. In these cases, the heart and lungs don't have to work harder. Sometimes these small holes will close up on their own.

There are different types of VSD. The type your child has depends on which part of the wall between the ventricles is involved. The size of the opening or hole also varies.

VSD may occur more often in some families. This is because of gene problems. Most of the time, doctors don't know the cause of VSD.

Your child may have symptoms from birth. Or your child may not have symptoms until they are a little older. The size of the opening or hole affects how severe your child's symptoms are. So does the age at which your child first has symptoms. If the hole is small, the only sign may be a heart murmur that your doctor hears with a stethoscope. With a larger opening, the heart and lungs have to work harder.

This can cause symptoms, such as :

• Tiredness
• Fast breathing
• Trouble breathing
• Pale skin
• Rapid heart rate
• Enlarged liver
• Poor feeding or tiring while feeding
• Poor weight gain

Symptoms can occur a bit differently in each child. The symptoms of VSD may also be similar to symptoms of other conditions. Make sure your child sees the doctor for a correct diagnosis.

Your child's doctor may suspect a problem when they hear an abnormal sound (heart murmur) when listening to your child's heart with a stethoscope. If this happens, the doctor may refer your child to a heart doctor for children (pediatric cardiologist).

The heart doctor will check your child. They will listen to your child's heart and lungs. The details about the murmur will also help the heart doctor make the diagnosis.

The heart doctor may do tests to confirm the diagnosis. The tests your child has depends on their age and condition, and the doctor's preferences.

A chest X-ray shows the heart and lungs. With a VSD, a chest X-ray may show an enlarged heart. This is because the left ventricle gets more blood than normal. There may also be changes in the lungs because of extra blood flow.

This test records the electrical activity of the heart. It also shows abnormal rhythms (arrhythmias) and spots heart muscle stress.

An echo uses sound waves to make a moving picture of the heart and heart valves. This test can show the pattern and amount of blood flow through the septal opening. An echo is used to diagnose VSD.

Treatment will depend on your child's symptoms, age, and general health. It will also depend on how severe the condition is.

A small VSD may close on its own as your child grows. Some small defects don't close on their own, but they still don't need treatment. A larger VSD often needs to be fixed with surgery or through cardiac catheterization. Once a child is diagnosed with a VSD, their heart doctor will check the defect regularly to see if it's closing on its own.

Some children may need to take medicine to help the heart work better. Children without symptoms may not need medicine.

Babies with a larger VSD may get tired when feeding. They may not be able to eat enough to gain weight. They may need:

• High-calorie formula or breast milk. Your child may need nutritional supplements added to their formula or pumped breast milk. This increases the number of calories in each ounce.
• Supplemental tube feedings. Your child may need to be fed through a small, flexible tube. This tube passes through the nose, down the esophagus, and into the stomach. Your child may have tube feedings along with or in place of bottle feedings. Babies who can drink part of their bottles may be fed the rest through a feeding tube. Infants who are too tired to bottle-feed may get all of their nutrition through the feeding tube.

The goal of surgery is to close the septal opening before the lungs are damaged. Surgery will also help babies who have trouble feeding gain a normal amount of weight. Your child's heart doctor will decide when your child should have surgery. This may be based on echocardiogram and cardiac catheterization results. In surgery, your child's doctor will close the VSD with stitches or a special patch. Ask your child's heart doctor for more information.

VSD may be fixed by a cardiac catheterization. In this test, a tool called a septal occluder is used with a catheter. The doctor guides the catheter through the blood vessels to the heart. Once the catheter is in the heart, the doctor closes the defect with the septal occluder. Only certain types of VSDs may be closed with this method. This procedure should be done in centers that have staff with experience in doing transcatheter VSD repair.

Complications of an untreated VSD include:

• Lung problems
• Heart failure
• Irregular heart rhythms (arrhythmias)
• Heart valve problems
• Poor growth and development

Babies with small VSDs may have no symptoms. These children may not need medicine. They'll still be checked often by their heart doctors. If a defect is going to close, it usually happens by age 2 . But some defects don't close until age 4. These children usually grow and develop normally. They also have no activity restrictions, and live normal, healthy lives.

If the VSD is moderate to severe, your child's heart doctor will closely monitor them. The doctor will decide when and how your child's VSD will be fixed. Before surgery, your child may need medicine and special feedings. Your child's health care team will give you information and support so you can care for your child at home. Children who need surgery will be admitted to the hospital for surgery.

Babies who have trouble eating before surgery often have more energy right after surgery. They start to eat better and gain weight faster.

After surgery, older children can often be active without getting too tired. Within a few weeks, your child should be fully recovered. They should be able to do normal activities. Your child's health care team may give you instructions on how to care for your child.

Most children who have surgery for VSD will live normal, healthy lives. Their activity levels, appetite, and growth often return to normal. Your child's heart doctor may give them antibiotics to prevent infections after leaving the hospital.

Ask your child's doctor about your child's outlook. When this condition is diagnosed early, the outcome is often excellent. The outlook may be poor when a VSD is diagnosed later in life, if complications occur after surgery, or if the VSD isn't fixed. There is a risk for complications from a VSD. Children at risk for these problems should have follow-up care at a center that specializes in congenital heart disease.

Contact the doctor if your child has:

• Trouble breathing
• Trouble eating
• Any new symptoms

• A VSD is an opening in the dividing wall between the two lower chambers of the heart.
• The size of the opening affects how severe your child's symptoms are.
• Small VSDs may close on their own as your child grows. If your child has a larger VSD, they will likely need surgery or a cardiac catheterization to fix it.
• Most children whose defects close on their own or who have VSD repairs will live normal, healthy lives.

Tips to help you get the most from a visit to your child's doctor:

• Know the reason for the visit and what you want to happen.
• Before your visit, write down questions you want answered.
• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you for your child.
• Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.
• Ask if your child's condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if your child does not take the medicine or have the test or procedure.
• If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your child's doctor after office hours and on weekends and holidays. This is important if your child becomes ill and you have questions or need advice.