What are the other Names for this Condition? (Also known as/Synonyms)

• ASD (Atrial Septal Defect)

What is Atrial Septal Defect? (Definition/Background Information)

• Congenital heart defects are relatively common birth defects involving the heart, and these may be of several types. Atrial Septal Defect (ASD) is a congenital heart abnormality characterized by the presence of a “hole” in the septum (wall) between the two upper chambers of the heart (i.e., the right atrium and left atrium)
• Due to this abnormality, there is mixing of oxygen-rich blood and oxygen-poor blood in the heart. The presence of Atrial Septal Defect also increases the amount of blood flow to the lungs, which can result in long-term damage of the heart and lung blood vessels resulting in abnormal heartbeats and pulmonary hypertension
• The severity of the condition depends on the size of the septal defect (hole), and the presence of other heart abnormalities. In some babies, the hole closes on its own over time; while in others, a surgical correction of Atrial Septal Defect may be necessary. In many cases, the prognosis of the condition is good

Who gets Atrial Septal Defect? (Age and Sex Distribution)

• Atrial Septal Defect affects the newborn child. It may be present at birth, but is sometimes not recognized until the child gets older (since some are mild and typically asymptomatic)
• The incidence of the condition is estimated to be around 1 in 1,900 babies
• Both male and female genders are affected
• No racial or ethnic predilection is generally observed

What are the Risk Factors for Atrial Septal Defect? (Predisposing Factors)

Currently, no risk factors for Atrial Septal Defect are definitively known. The following may increase one’s risk for the same:

• A family history of heart structural abnormalities
• Exposure of the pregnant woman to environmental toxins and certain medications

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Atrial Septal Defect? (Etiology)

The exact cause of development of Atrial Septal Defect (ASD) is not well-understood. It may develop from a combination of factors that may be genetic and environmental. It is also believed that what the expectant mother consumes, such as food, drink, or even some medications, may be contributive.

• Generally, in the fetal developmental stage, there is an opening on the wall separating the right and left atrium that avoids blood flow to the fetal lungs
• During pregnancy or following the birth of the child, the hole decreases in size and closes within weeks and months. In some children, the hole may be large and does not close normally, resulting in an Atrial Septal Defect
• The severity of the condition is based on the size of the hole that can vary from one child to another. The associated signs and symptoms are mainly based on the magnitude of the defect (hole) and the presence of other underlying heart anomalies, if any seen

What are the Signs and Symptoms of Atrial Septal Defect?

Mild cases of Atrial Septal Defect, where the hole is small in size, may be present without any signs and symptoms for a long period, sometimes even into adulthood. The signs and symptoms observed in other cases may include:

• Heart murmur (a whooshing sound may be heard via a stethoscope)
• Heart palpitations; abnormal heartbeat
• Shortness of breath, usually after exercise or physical activity (this may be even observed in infants who are generally active)
• Fatigue
• Swelling in the legs (feet) or abdomen
• Infants feel tired upon feeding

How is Atrial Septal Defect Diagnosed?

The diagnostic tests and exams for Atrial Septal Defect may include:

• Physical exam with evaluation of medical history. This includes listening to the heart using a stethoscope, to detect any unusual ‘whooshing’ sound
• Assessment of the presenting signs and symptoms, particularly breathing difficulties, tiredness, and frequent infections
• Newborn pulse oximetry screening may help the healthcare suspect the condition prior to symptom presentation
• Electrocardiogram (EKG), to measure electrical activity of the heart
• Fetal echocardiogram may be commonly used to confirm the diagnosis
• Chest X-ray, CT and MRI scan studies of the chest and abdomen, as needed
• Cardiac catheterization

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Atrial Septal Defect?

Complications due to Atrial Septal Defect are mostly due to a delay in detection and treatment of the condition and/or due to the presence of other accompanying heart defects. These include:

• Frequent lung infections
• High blood pressure in the lungs (pulmonary hypertension)
• Heart failure
• Stroke - there is an increased risk for a brain stroke
• Post-surgical complications

How is Atrial Septal Defect Treated?

The treatment of Atrial Septal Defect is based on the severity of the presenting signs and symptoms, the magnitude of the defect (wall), the overall health condition, and other associated medical conditions (if any). Management of the condition involves correcting the defect(s) and providing symptomatic treatment that includes:

• Medications to address the symptoms
• Surgery to correct the defect (closure of the hole):
  • It may be undertaken during the cardiac catheterization
  • Open heart surgery may be performed to rectify the defect
• Medications to help the child heal post-surgery
• Regular health check-ups are essential

Taking steps to maintain a healthy heart after the surgery is important. This may be accomplished by:  

• Avoidance of smoking
• Avoiding high-fat diets (to prevent obesity)
• Limiting alcohol consumption
• Exercising regularly (per advise of the physician)
• Having a healthy diet
• Managing stress

How can Atrial Septal Defect be Prevented?

Presently, there are no available guidelines to prevent Atrial Septal Defect.

• Detecting early signs and symptoms combined with a timely diagnosis, holds the key to managing the disorder
• Identifying other accompanying heart ailments and preventing further complications is important
• Avoid non-prescriptive medications during pregnancy that may harm the fetus
• Folic acid intake: Tests and researches have proved that sufficient intake of folic acid decreases the risk for birth defects

Regular medical screening at periodic intervals with tests, scans, and physical examinations are mandatory for those who have already undergone surgical correction of the defect. Often, several years of active vigilance may be necessary.

What is the Prognosis of Atrial Septal Defect? (Outcomes/Resolutions)

The prognosis of Atrial Septal Defect (ASD) is generally good with adequate treatment.

• In some cases, the defect resolves spontaneously, and no surgical interventions may be necessary
• In individuals with severe ASD, a surgery may be necessary to correct the defect. In most cases, the outcomes of surgery to repair the defect is good
• A late recognition of the condition and lack of appropriate treatment may lead to complications and adverse outcomes

Additional and Relevant Useful Information for Atrial Septal Defect:

The following DoveMed website link is a useful resource for additional information:

https://www.dovemed.com/healthy-living/heart-center/