An atrioventricular canal defect (AVCD) is a birth defect of the heart.
The heart normally has 2 upper chambers (atria) and 2 lower chambers (ventricles). The wall of tissue that separates the right and left sides of the heart is called the septum. A normal heart has 2 heart valves that separate the upper and lower chambers. The valves and septum together are called the atrioventricular canal. Normally the left side of the heart pumps blood to the body, and the right side pumps blood to the lungs.
In AVCD, there are holes in the walls between the chambers of the heart, and the valves that control blood flow may not work well. With AVCD, blood flows where it should not and more blood gets pumped into the lungs. The heart has to work harder and it gets bigger.
AVCD is also called atrioventricular septal defect or endocardial cushion defect.
The cause of this birth defect is not known. It is most common in babies with Down syndrome.
The symptoms may start at any time from birth to several months after birth. Symptoms may include:
Many defects cause a whooshing sound, called a murmur, as blood moves through the heart. Healthcare providers can hear the murmur with a stethoscope.
AVCD can be diagnosed before birth, using screening tests to check for birth defects. If the defect is large enough, tests that may show the problem include:
After birth, your child’s healthcare provider will ask about your child's symptoms and medical history and examine your child. In addition to an echocardiogram done after birth, other tests may include:
Sometimes heart catheterization may be needed. A catheter is a very thin tube that is passed through a blood vessel into the heart. The pressure in the chambers of the heart is measured and blood samples can be taken. This helps to tell how big the defect is.
Your child will need surgery to repair the AVCD. Your baby may need to take medicines until he is strong enough to have surgery.
If your baby is very sick, or the defect can’t be fixed all at once, your baby may have a procedure to reduce blood flow to the lungs. Your child’s healthcare provider can put a band around the lung artery to make it narrower. Then the heart will not have to work as hard, and the lungs will be protected from high blood pressure. When your child is older, the band can be removed and open heart surgery done.
Your child may need to have regular follow-up visits with a specialist in congenital heart disease.
Follow your child’s healthcare provider's instructions. Ask your provider:
Make sure you know when your child should come back for a checkup. Keep all appointments for provider visits or tests.