Atrial Septal Defect

Overview

An atrial septal defect (ASD) is a hole in the heart that occurs between the upper chambers (atria). This congenital heart defect increases the amount of blood flowing through the lungs. Small ASDs may not cause any concerns and may close on their own during infancy or early childhood. However, a large, long-term ASD can damage the heart and lungs, requiring surgical intervention to repair the defect and prevent complications. There are two types of ASDs: secundum and primum. Secundum is the most common type, occurring in the middle of the atrial septum, while primum involves the lower part of the atrial septum and may occur with other heart defects.

Understanding the disease

Symptoms

Symptoms of atrial septal defect (ASD) may include shortness of breath, especially during exercise, fatigue, swelling of legs, feet, or belly, irregular heartbeats (arrhythmias), a sensation of a rapid, pounding heartbeat (palpitations) or skipped beats, and a whooshing sound that can be heard through a stethoscope (heart murmur).

Risk Factors

The risk factors for developing atrial septal defect include genetics, certain medical conditions such as German measles (rubella) infection during pregnancy, diabetes, lupus, alcohol or tobacco use, and illegal drug use. Use of certain medications, including some anti-seizure medications and drugs to treat mood disorders, can also increase the risk. Some types of congenital heart defects occur in families (inherited), and screening by a genetic counselor can help determine the risk of certain heart defects in future children.

Development

The various atrial septal defects (ASDs) develop differently. Here's a brief overview of each type:

1. Secundum: This is the most common type of ASD, occurring in the middle of the wall between the upper heart chambers (atrial septum). It is present at birth and can be small, causing no symptoms or concerns. Small ASDs may close on their own during infancy or early childhood. A large, long-term ASD can damage the heart and lungs, requiring surgery for repair and to prevent complications.
2. Primum: This type of ASD affects the lower part of the atrial septum and might occur with other congenital heart defects. It is less common than secundum ASD and can lead to more severe symptoms due to the location of the defect.
3. Sinus venosus: This rare type of ASD usually occurs in the upper part of the wall separating the heart chambers. It is also associated with other heart structure changes present at birth.
4. Coronary sinus: In this rare type of ASD, part of the wall between the coronary sinus (which is part of the vein system of the heart) and the left upper heart chamber (left atrium) is missing. ASDs are congenital heart defects, meaning they develop during pregnancy. The specific cause of ASDs is often unknown, but genetics, certain medical conditions, use of certain medications, and environmental or lifestyle factors, such as smoking or alcohol misuse, may play a role in their development.

Assessment and Diagnosis

Triage

You should see a doctor if you or your child experiences the following symptoms, as they may indicate atrial septal defect: shortness of breath, easy tiring, especially after activity, swelling of legs, feet, or belly (abdomen), sensations of a rapid, pounding heartbeat (palpitations) or skipped beats, a whooshing sound that can be heard through a stethoscope (heart murmur).

Diagnosis

To diagnose an atrial septal defect (ASD), healthcare providers typically use the following tests:

1. Echocardiogram: This test is the most common diagnostic tool for ASD. Sound waves are used to create images of the heart, revealing how blood flows through the heart and heart valves.
2. Chest X-ray: This test can show the condition of the heart and lungs, providing information about the overall structure and size of the heart.
3. Electrocardiogram (ECG or EKG): This painless test records the electrical activity of the heart, helping to identify irregular heartbeats (arrhythmias) or other abnormalities.

Management and Treatment

Complications

Potential complications of atrial septal defect include right-sided heart failure, irregular heartbeats (arrhythmias), stroke, early death, and high blood pressure in the lung arteries (pulmonary hypertension). Pulmonary hypertension can cause permanent lung damage, leading to Eisenmenger syndrome. Treatment can prevent or manage these complications.

Treatment

Treatment for atrial septal defect (ASD) depends on the size and severity of the defect, as well as any associated symptoms or complications. Here are some common treatment options for ASD:

1. Monitoring: For small atrial septal defects that don't cause significant symptoms or complications, your doctor may recommend monitoring the condition regularly. Your child's doctor will monitor the size of the defect and any changes in symptoms.
2. Medications: Some medications may be prescribed to help manage symptoms or complications associated with ASD. These may include diuretics to help manage fluid buildup, or medications to control irregular heartbeats or high blood pressure.
3. Surgery: Surgery is typically recommended for larger atrial septal defects or those that cause significant symptoms or complications. The most common surgical procedure to repair an ASD is called a catheterization procedure. During this procedure, a small tube (catheter) is inserted into a blood vessel in the leg and guided to the heart, where a device is used to close the hole in the atrial septum. It's important to consult with a pediatric cardiologist or healthcare provider experienced in treating heart defects for personalized advice and recommendations based on your specific situation.

Preparing for medical consultation

To prepare for an appointment for an atrial septal defect, you should:

1. Note any symptoms: Write down any symptoms you or your child are experiencing, even if they seem unrelated to heart problems. Be specific about when they began.
2. Gather personal information: Collect information about your family history of congenital heart disease or other heart or lung diseases, any lifestyle choices during pregnancy, and any illnesses during pregnancy.
3. Create a list of questions: Prepare a list of questions to ask the healthcare provider, such as what tests are needed, what treatments are available, and whether there are any restrictions to follow.
4. Bring a family member or friend: Consider bringing a loved one to the appointment for support and to help remember the information provided.
5. Be aware of pre-appointment restrictions: Inquire about any pre-appointment requirements, such as filling out forms or modifying your diet before certain tests.
6. Document medications: Make a list of all medications, vitamins, or supplements you or your child are taking, including dosages. Remember to be proactive in sharing your concerns and asking questions during the appointment. This will help you and your healthcare provider make the most of your time together.