What are common congenital heart defects?

Although the term "heart defect" can refer to many different heart problems, it's often used to talk about defects in the wall (septum) that divides the two upper or two lower chambers of the heart. Three of the more common defects are:

• Atrial septal defect (ASD). This congenital defect (birth defect) is fairly common. With ASD, there is a hole in the wall between the left atrium and right atrium, the two upper chambers of the heart. The hole allows oxygen-rich and oxygen-poor blood to mix and overfills the right atrium with blood. As a result, too much blood flows into the right ventricle and lungs. Your heart has to work harder, and your lungs can be damaged.
• Patent foramen ovale (PFO). Fetuses have a normal opening (called a foramen ovale) between the left and right atria of the heart. But if this opening fails to close naturally soon after birth, the result is an open (patent) foramen ovale, or PFO. Most of the time, this defect doesn't cause significant health problems and doesn't require treatment. When a PFO is serious enough to cause problems, healthcare providers may recommend a procedure to close the hole.
• Ventricular septal defect (VSD). This problem -- which may be a birth defect or a result of damage to the heart -- is a hole in the wall between the two lower chambers of the heart (the ventricles). With a VSD, oxygen-rich blood from the heart's left ventricle is forced through the hole into the right ventricle. The blood is then pumped back to the lungs -- even though it's already been refreshed with oxygen. This is inefficient and makes your heart work harder.