If you are experiencing a medical emergency please dial 911 immediately
It is possible that the main title of the report Atrioventricular Septal Defect is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.
Atrioventricular septal defect (ASVD) is a general term for a group of rare heart defects that are present at birth (congenital). Infants with ASVDs have improperly developed atrial and ventricular septa and adjoining valves.
The normal heart has four chambers. The two upper chambers, known as atria, are separated from each other by a fibrous partition called the atrial septum. The two lower chambers, known as ventricles, are separated from each other by the ventricular septum. Valves (e.g., mitral and tricuspid) connect the atria (left and right) to their respective ventricles. The valves allow for blood to be pumped through the chambers. Blood travels from the right ventricle through the pulmonary artery to the lungs where it receives oxygen. The blood returns to the heart through pulmonary veins and enters the left ventricle. The left ventricle sends the now oxygen-filled blood into the main artery of the body (aorta). The aorta sends the blood throughout the body.
The parts of the heart described above are formed from an embryonic structure called the endocardial cushions. In individuals with ASVD there is some combination of malformation of these parts of the heart. They may include a hole in the atrial septum, a hole in the ventricular septum, and/or abnormalities of the mitral and triscupid valves. ASVD may be classified as one of three forms: an incomplete (or partial) ASVD (atrial septal defect primum); a transitional form (atrial septal defect and small ventricular septal defect); or a more severe or complete form (large atrial and ventricular defects).
The symptoms of ASVD vary greatly and depend on the severity of the malformations (e.g., valve leakage between ventricles and ventricular size). About half the cases of ASVD occur in children with Down syndrome.
American Heart Association
7272 Greenville Avenue
Dallas, TX 75231
American Lung Association
1301 Pennsylvania Ave NW
Washington, DC 20004
NIH/National Heart, Lung and Blood Institute
P.O. Box 30105
Bethesda, MD 20892-0105
Kids With Heart ~ National Association for Children's Heart Disorders, Inc.
1578 Careful Dr.
Green Bay, WI 54304
Little Hearts, Inc.
P.O. Box 171
110 Court Street, Suite 3A
Cromwell, CT 06416
Congenital Heart Information Network (C.H.I.N.)
P.O. Box 3397
Margate City, NJ 08402-0397
Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to www.rarediseases.org and click on Rare Disease Database under "Rare Disease Information".
The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.
It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report
This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.
For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site www.rarediseases.org or email email@example.com
Last Updated: 2/11/2008
Copyright 1986, 1994, 2005 National Organization for Rare Disorders, Inc.
Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.