Atrioventricular septal defects (AVSD) are a group of heart defects present at birth (congenital). Normally the four heart chambers are separated by walls (septum) to keep oxygen rich and oxygen poor blood separate. The blood flow between the chambers is controlled by valves. AVSDs are caused by a hole being present in the upper chambers (atrium) which allows a mixing of blood. AVSDs may also include defects in the AV valves. These birth defects cause the heart to send too much blood to the lungs. The overworked heart enlarges and causes the blood pressure in the lungs to become too high. Ultimately, an AVSD can lead to heart failure.
Common symptoms include difficulty breathing, abnormal heartbeats (arrhythmia), and poor blood circulation, which can cause bluish lips and skin and swelling in the legs (edema). Children with an AVSD may also have poor appetite and become tired easily. Sometimes symptoms may not appear for weeks or months after birth. The causes of AVSDs are believed to be a combination of genetics and environment. Babies with Down syndrome are at an increased risk for developing the condition. Other risk factors include the mother drinking alcohol during pregnancy or poorly controlled maternal diabetes.
Doctors may hear a swishing sound in the heartbeat (a murmur) when listening with a stethoscope. Tests used to confirm a VSD may include a chest X-ray, electrocardiogram (EKG) (tests the electrical impulses), echocardiogram (used sound waves to create a picture), or cardiac MRI.
Smaller defects may close on their own, but the most common treatment is surgical repair. If your baby or child has been diagnosed with an AVSD, talk to their pediatric cardiologist (a heart doctor for children) about the most current treatment options. Support organizations and genetic counselors are also a good source of information and can help connect you with others affected by AVSDs.