Diseases & Conditions


Atrioventricular Septal Defect

Synonyms of Atrioventricular Septal Defect
  • Atrioventricular Canal Defects
  • AVSD
  • Common Atrioventricular Canal (CAVC) Defect
  • Endocardial Cushion Defects

Disorder Subdivisions

  • Complete Atrioventricular Septal Defect
  • Incomplete Atrioventricular Septal Defect
  • Partial Atrioventricular Septal Defect
  • Transitional Atrioventricular Septal Defect

General Discussion
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.

Organizations related to Atrioventricular Septal Defect
  • American Heart Association
    National Center
    Dallas TX 75231-4596
    Phone #: 214-373-6300
    800 #: 800-242-8721
    e-mail: [email protected]
    Home page: http://www.americanheart.org
  • American Lung Association
    61 Broadway, 6th Floor
    New York NY 10006
    Phone #: 212-315-8700
    800 #: 800-586-4872
    e-mail: N/A
    Home page: http://www.lungusa.org
  • Congenital Heart Anomalies, Support, Education, & Resources
    2112 North Wilkins Road
    Swanton OH 43558
    Phone #: 419-825-5575
    800 #: --
    e-mail: [email protected]
    Home page: http://www.csun.edu/~hcmth011/chaser/chaser-news.html
  • Congenital Heart Information Network
    1561 Clark Dr
    Yardley PA 19067
    Phone #: 215-493-3068
    800 #: --
    e-mail: [email protected]
    Home page: http://www.tchin.org
  • Kids With Heart National Association for Children's Heart Disorders, Inc.
    1578 Careful Dr
    Green Bay WI 54304-2941
    Phone #: 920-498-0058
    800 #: 800-538-5390
    e-mail: [email protected]
    Home page: http://www.kidswithheart.org
  • Little Hearts, Inc.
    P.O. Box 171
    Cromwell CT 06416
    Phone #: 860-635-0006
    800 #: 866-435-4673
    e-mail: [email protected]
    Home page: http://www.littlehearts.org
  • MUMS (Mothers United for Moral Support, Inc) National Parent-to-Parent Network
    150 Custer Court
    Green Bay WI 54301-1243
    Phone #: 920-336-5333
    800 #: 877-336-5333
    e-mail: [email protected]
    Home page: http://www.netnet.net/mums/
  • NIH/National Heart, Lung and Blood Institute Information Center
    P.O. Box 30105
    Bethesda MD 20824-0105
    Phone #: 301-592-8573
    800 #: --
    e-mail: [email protected]
    Home page: N/A

For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders, Inc. ? (NORD). A copy of the complete report can be obtained for a small fee by visiting the NORD website. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational treatments (if available), and references from medical literature. For a full-text version of this topic, see http://www.rarediseases.org/search/rdblist.html