Endocardial Cushion Defect - Minnesota Department of Health

Endocardial Cushion Defect (also called atrioventricular (AV) canal or septal defects)

Condition Description

Endocardial cushion defects are congenital heart conditions that occur early in fetal life due to improperly developed heart tissue in the center of the heart (the endocardial cushion area of the heart). This results in a range of defects that are included in this category of endocardial cushion defects.

These include conditions such as atrioventricular canal (called AV canal), atrial septal defects (ASDs), ventricular septal defects (VSDs), and conditions involving the valves within the heart (the AV valves). There are 2 general categories of endocardial cushion defects: the complete form of endocardial defect (involving atria, ventricles and valves), and the partial form of endocardial defect (typically involving the atria only). These conditions have unique characteristics, and each child's heart structure is quite unique within this category of disorders. In addition to holes between the chambers of the heart, the valves may be improperly placed or the leaflets of the valves may not be completely formed for good closing function.

The symptoms will vary greatly, depending on the size and location of the defects. Partial defects may not be discovered until later in life because they cause few symptoms. The complete form of the endocardial defects can severely affect a baby's health. Because the left side of the heart is the stronger pump, blood that has received oxygen typically passes through the holes between the chambers (called left-to-right shunt), overloading the right side of the heart. The problems with valve closure can also overload the heart.

Individuals with congenital heart defects will typically require antibiotics when they have dental work because the bacteria in the mouth can circulate through the blood and cause infection in the heart structures (endocarditis). They will need to be followed long-term by cardiologists to be sure that any complications or new conditions are quickly detected and treated.

Our program has been tracking Atrioventricular septal defect (Endocardial cushion defect) among live births in select counties since 2005 and gradually expanding statewide.

  • Using data from births to Hennepin and Ramsey county residents between 2012-2016, we found that 5.6 babies were born with atrioventricular septal defect per 10,000 births.
  • Using this data, we estimate about 37 babies are born with atrioventricular septal defect every year in Minnesota.

Condition Specific Resources

  • Medscape: Endocardial Cushion Defect

Additional Information

Additional information and resources for families are available.
Updated Friday, 10-Jan-2020 16:27:18 CST