Atrioventricular Septal Defect
(Atrioventricular Canal Defect; Endocardial Cushion Defect)
Definition
The heart is divided into four chambers that help circulate blood through the body. The top two chambers are called atria. The bottom two chambers are called ventricles. Two valves are between the upper and lower chambers. Tissue called the septum divides the chambers. The tissue grows as the fetus develops.
An atrioventricular septal defect is present at birth. It occurs when any of the tissues that divide the septum do not grow completely. This leaves one or more "holes." It may also leave one leaky valve instead of two separate valves.
The heart may have to work harder to circulate blood correctly. Open-heart surgery is often needed to correct the defect in babies.
Causes
The septal tissue fails to grow correctly as the fetus develops in the womb. This results in atrioventricular septal defect.
Risk Factors
Risk factors that increase the chance that a baby will be born with a ventricular septal defect include:
- A family history of heart defects
-
Down syndrome
—Nearly one in five babies with Down syndrome will have this heart defect
-
Alcohol consumption
or
drug abuse
by the mother during pregnancy
-
A
mother
with
diabetes
-
Rubella infection
during the first three months of pregnancy
- Exposure to thalidomide, anticonvulsant medications, or lithium salts while in the womb
- Exposure to certain industrial chemicals during pregnancy
Symptoms
Symptoms include:
- Difficulty feeding, such as sweating or shortness of breath while eating
- Failing to gain weight
- Lung congestion
- A bluish tint to lips and fingernails, called cyanosis
Diagnosis
Your doctor will ask about your baby's symptoms and medical history. A physical exam will be done.
- Your doctor may need pictures of your baby's heart. This can be done with a Chest x-ray.
- Your doctor may need information about how your baby's heart functions. This can be done with:
Treatment
A doctor may recommend any of the following treatments for your baby:
- Medicines to strengthen the heart, keep the heartbeat regular, or decrease the amount of fluid in circulation
- A
pacemaker
to regulate the heart
- A high calorie diet and/or breastfeeding to manage poor weight gain
- Ongoing observation of the symptoms and the defect
- Limited physical activity depending on the severity of the defect
- Counseling to help you adjust to your baby's diagnosis and treatment
- Surgery in early childhood to close the hole (recommended when the defect is severe)
- Diuretics and digoxin to treat heart failure
- Antibiotics before and after surgery to reduce the risk of bacterial infections
Prevention
It may not be possible to prevent the condition because the exact cause is unknown. A septal defect can be identified, watched, and treated early in pregnancy and childhood:
- If you are pregnant or planning to become pregnant, seek early and regular prenatal care, get exercise, and eat a well-balanced diet.
- Control your blood sugar levels if you have diabetes.
- Avoid drugs, cigarettes, and alcohol.
- A prenatal ultrasound when the fetus is 10-14 weeks old will identify many babies with
heart defects.
- If you have a child with this defect, consult a genetics counselor to find out if your future children are also at risk.
RESOURCES
American Association of Family Physicians
http://familydoctor.org
American Heart Association
http://www.heart.org
CANADIAN RESOURCES
Canadian Adult Congenital Heart Network
http://www.cachnet.org
Canadian Heart and Stroke Foundation
http://www.heartandstroke.com/
References
Atrial septal defect. EBSCO DynaMed website. Available at:
http://www.ebscohost.com/dynamed.
Updated June 6, 2012. Accessed November 10, 2012.
Atrioventricular septal defect, complete. Cove Point Foundation website. Available at: http://www.pted.org/?id=atrioventricularcomplete1. Updated May 16, 2011. Accessed November 10, 2012.
Saenz R, Beebe D, Triplett L. Caring for infants with congenital heart disease and their families.
Am Fam Physician
. 1999;59. Available at:
http://www.aafp.org/afp/990401ap/1857.html
. Accessed
November 10, 2012.
Ventricular septal defect. EBSCO DynaMed website. Available at:
http://www.ebscohost.com/dynamed.
Updated June 14, 2012. Accessed November 10, 2012.